chore(release): bump version to 1.6.0

Anime releases often carry two subtitle tracks in one language, the
dialogue and a "Signs & Songs" track, and the second is as often as not
the one marked default or forced. mpv, picking by language, played it.

pstr_core::subtitles reads a track's name and forced flag for whether it
is the dialogue, and every client asks it once per file, after mpv has
made its own pick, whether to switch to a track in the same language
that is. A subtitle track the viewer chose by name stays, and subtitles
that are off stay off.

.github/workflows/android.yml

@@ -3,7 +3,15 @@ name: Android
 on:
   push:
     branches: [main]
-    tags: ['v*']
+  # A `v*` tag reaches this workflow through release.yml, which calls it and
+  # publishes the signed APK. Triggering on the tag here as well would build
+  # the release twice.
+  workflow_call:
+    inputs:
+      signed_release:
+        required: false
+        default: false
+        type: boolean
   pull_request:
     paths:
       - 'android/**'
@@ -31,8 +39,8 @@ env:
   CARGO_TERM_COLOR: always
   ANDROID_API: '36'
   ANDROID_BUILD_TOOLS: '37.0.0'
-  ANDROID_NDK: '29.0.14206865'
+  ANDROID_NDK: '30.0.16248370'
-  ANDROID_NDK_HOME: /usr/local/lib/android/sdk/ndk/29.0.14206865
+  ANDROID_NDK_HOME: /usr/local/lib/android/sdk/ndk/30.0.16248370
 
 jobs:
   build:
@@ -74,14 +82,23 @@ jobs:
           distribution: temurin
           java-version: '17'
 
+      # The action's default `packages` includes `tools`, which cmdline-tools
+      # 16.0 no longer offers, so sdkmanager exits 1. The SDK pieces this
+      # build needs are installed explicitly below.
       - uses: android-actions/setup-android@v3
+        with:
+          packages: platform-tools
+          log-accepted-android-sdk-licenses: false
 
       - name: Install native build prerequisites
         run: |
           sudo apt-get update
           sudo apt-get install --no-install-recommends \
-            autoconf automake build-essential cmake curl git gperf libtool \
+            autoconf automake build-essential cmake curl git gperf libdbus-1-dev \
-            meson nasm ninja-build pkg-config python3 unzip wget xz-utils yasm
+            libtool nasm ninja-build pkg-config python3 unzip wget xz-utils yasm
+          # Not apt's meson: noble ships 1.3.2, and the fontconfig that the pinned
+          # mpv-android revision builds requires >= 1.11.
+          pipx install meson==1.12.1
 
       - name: Install Android SDK and NDK
         run: >-
@@ -90,12 +107,53 @@ jobs:
           "build-tools;${ANDROID_BUILD_TOOLS}"
           "ndk;${ANDROID_NDK}"
 
-      - uses: dtolnay/rust-toolchain@stable
+      - id: toolchain
+        uses: dtolnay/rust-toolchain@stable
         with:
           toolchain: '1.96'
           targets: aarch64-linux-android,x86_64-linux-android
 
+      # The registry and the installed helpers only. rust-cache reads
+      # `target/android/<triple>` as a profile directory and deletes the
+      # `release` tree under it before saving, so with its target caching on
+      # every run rebuilt both ABIs from scratch.
       - uses: Swatinem/rust-cache@v2.9.1
+        with:
+          shared-key: android-registry
+          cache-targets: false
+          cache-on-failure: true
+
+      # The target directory as is: the host build the UniFFI bindings come
+      # from and both cargo-ndk ABIs. One entry for both jobs, since the signed
+      # build compiles the same crates for the same targets. A new lockfile
+      # starts from the last one's tree, so a version bump rebuilds only the
+      # workspace crates.
+      - id: target
+        uses: actions/cache/restore@v6
+        with:
+          path: target
+          key: rust-target-android-${{ steps.toolchain.outputs.cachekey }}-${{ hashFiles('Cargo.lock') }}
+          restore-keys: rust-target-android-${{ steps.toolchain.outputs.cachekey }}-
+
+      # libmpv and its dependency tree are the slowest part of the build, and
+      # depend only on the pinned revision and the build script, which stamps
+      # its output with both and skips the build when the stamp matches. Built
+      # and saved in steps of its own, so a later failure in Gradle does not
+      # discard it the way a post-job cache save would.
+      - id: libmpv
+        uses: actions/cache/restore@v6
+        with:
+          path: android/app/build/generated/mpv
+          key: libmpv-${{ hashFiles('scripts/build-libmpv-android.sh') }}
+
+      - name: Build libmpv
+        run: bash scripts/build-libmpv-android.sh
+
+      - if: steps.libmpv.outputs.cache-hit != 'true'
+        uses: actions/cache/save@v6
+        with:
+          path: android/app/build/generated/mpv
+          key: ${{ steps.libmpv.outputs.cache-primary-key }}
 
       - uses: gradle/actions/setup-gradle@v4
         with:
@@ -124,9 +182,15 @@ jobs:
       - name: Android checks and artifacts
         run: bash scripts/build-android.sh all
 
+      - if: steps.target.outputs.cache-hit != 'true'
+        uses: actions/cache/save@v6
+        with:
+          path: target
+          key: ${{ steps.target.outputs.cache-primary-key }}
+
   signed-release:
     name: Signed release
-    if: false
+    if: startsWith(github.ref, 'refs/tags/v') || inputs.signed_release
     needs: build
     runs-on: ubuntu-24.04
     env:
@@ -141,14 +205,23 @@ jobs:
           distribution: temurin
           java-version: '17'
 
+      # The action's default `packages` includes `tools`, which cmdline-tools
+      # 16.0 no longer offers, so sdkmanager exits 1. The SDK pieces this
+      # build needs are installed explicitly below.
       - uses: android-actions/setup-android@v3
+        with:
+          packages: platform-tools
+          log-accepted-android-sdk-licenses: false
 
       - name: Install native build prerequisites
         run: |
           sudo apt-get update
           sudo apt-get install --no-install-recommends \
-            autoconf automake build-essential cmake curl git gperf libtool \
+            autoconf automake build-essential cmake curl git gperf libdbus-1-dev \
-            meson nasm ninja-build pkg-config python3 unzip wget xz-utils yasm
+            libtool nasm ninja-build pkg-config python3 unzip wget xz-utils yasm
+          # Not apt's meson: noble ships 1.3.2, and the fontconfig that the pinned
+          # mpv-android revision builds requires >= 1.11.
+          pipx install meson==1.12.1
 
       - name: Install Android SDK and NDK
         run: >-
@@ -157,12 +230,53 @@ jobs:
           "build-tools;${ANDROID_BUILD_TOOLS}"
           "ndk;${ANDROID_NDK}"
 
-      - uses: dtolnay/rust-toolchain@stable
+      - id: toolchain
+        uses: dtolnay/rust-toolchain@stable
         with:
           toolchain: '1.96'
           targets: aarch64-linux-android,x86_64-linux-android
 
+      # The registry and the installed helpers only. rust-cache reads
+      # `target/android/<triple>` as a profile directory and deletes the
+      # `release` tree under it before saving, so with its target caching on
+      # every run rebuilt both ABIs from scratch.
       - uses: Swatinem/rust-cache@v2.9.1
+        with:
+          shared-key: android-registry
+          cache-targets: false
+          cache-on-failure: true
+
+      # The target directory as is: the host build the UniFFI bindings come
+      # from and both cargo-ndk ABIs. One entry for both jobs, since the signed
+      # build compiles the same crates for the same targets. A new lockfile
+      # starts from the last one's tree, so a version bump rebuilds only the
+      # workspace crates.
+      - id: target
+        uses: actions/cache/restore@v6
+        with:
+          path: target
+          key: rust-target-android-${{ steps.toolchain.outputs.cachekey }}-${{ hashFiles('Cargo.lock') }}
+          restore-keys: rust-target-android-${{ steps.toolchain.outputs.cachekey }}-
+
+      # libmpv and its dependency tree are the slowest part of the build, and
+      # depend only on the pinned revision and the build script, which stamps
+      # its output with both and skips the build when the stamp matches. Built
+      # and saved in steps of its own, so a later failure in Gradle does not
+      # discard it the way a post-job cache save would.
+      - id: libmpv
+        uses: actions/cache/restore@v6
+        with:
+          path: android/app/build/generated/mpv
+          key: libmpv-${{ hashFiles('scripts/build-libmpv-android.sh') }}
+
+      - name: Build libmpv
+        run: bash scripts/build-libmpv-android.sh
+
+      - if: steps.libmpv.outputs.cache-hit != 'true'
+        uses: actions/cache/save@v6
+        with:
+          path: android/app/build/generated/mpv
+          key: ${{ steps.libmpv.outputs.cache-primary-key }}
 
       - uses: gradle/actions/setup-gradle@v4
         with:
@@ -188,10 +302,30 @@ jobs:
       - name: Build signed APK and AAB
         run: bash scripts/build-android.sh signed
 
+      - if: steps.target.outputs.cache-hit != 'true'
+        uses: actions/cache/save@v6
+        with:
+          path: target
+          key: ${{ steps.target.outputs.cache-primary-key }}
+
+      # The APK bundles a GPL libmpv, so its corresponding source ships next to
+      # it. The AAB is for Play only and stays out of the GitHub release.
+      - name: Stage release files
+        run: |
+          version="$(sed -n 's/^version = "\([^"]*\)"/\1/p' Cargo.toml | head -n1)"
+          mkdir -p dist/android
+          cp android/app/build/outputs/apk/release/app-release.apk \
+            "dist/android/proton-stream-$version-android.apk"
+          cp android/app/build/generated/mpv/mpv-android-source-*.tar.gz dist/android/
+
       - uses: actions/upload-artifact@v7
         with:
-          name: android-signed
+          name: android
-          path: |
+          path: dist/android/*
-            android/app/build/outputs/apk/release/*.apk
+          if-no-files-found: error
-            android/app/build/outputs/bundle/release/*.aab
+
+      - uses: actions/upload-artifact@v7
+        with:
+          name: android-bundle
+          path: android/app/build/outputs/bundle/release/*.aab
           if-no-files-found: error

.github/workflows/ci.yml

@@ -23,11 +23,11 @@ jobs:
 
       - uses: Swatinem/rust-cache@v2.9.1
 
-      # libmpv for pstr-player.
+      # libmpv for pstr-player, WebKitGTK for the CAPTCHA window.
-      - name: Install libmpv
+      - name: Install libmpv and WebKitGTK
         run: |
           sudo apt-get update
-          sudo apt-get install -y libmpv-dev
+          sudo apt-get install -y libmpv-dev libwebkit2gtk-4.1-dev
 
       - run: cargo fmt --all -- --check
 

.github/workflows/ios.yml

@@ -0,0 +1,71 @@
+name: iOS
+
+on:
+  push:
+    branches: [main]
+  workflow_call:
+  pull_request:
+    paths:
+      - 'ios/**'
+      - 'android/app/src/main/res/font/**'
+      - 'android/app/src/main/assets/licenses/**'
+      - 'crates/pstr-android/**'
+      - 'crates/pstr-core/**'
+      - 'crates/pstr-meta/**'
+      - 'crates/pstr-stream/**'
+      - 'Cargo.toml'
+      - 'Cargo.lock'
+      - 'scripts/build-ios.sh'
+      - '.github/workflows/ios.yml'
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+env:
+  CARGO_TERM_COLOR: always
+
+jobs:
+  build:
+    name: Unit tests and unsigned .ipa
+    runs-on: macos-15
+    steps:
+      - uses: actions/checkout@v7
+
+      - id: toolchain
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: '1.96'
+          targets: aarch64-apple-ios,aarch64-apple-ios-sim
+
+      - name: Restore the Rust target tree
+        uses: actions/cache@v6
+        with:
+          path: |
+            ~/.cargo/registry
+            ~/.cargo/git
+            target
+          key: rust-target-ios-${{ steps.toolchain.outputs.cachekey }}-${{ hashFiles('Cargo.lock') }}
+          restore-keys: rust-target-ios-${{ steps.toolchain.outputs.cachekey }}-
+
+      - name: Install XcodeGen
+        run: brew install xcodegen
+
+      - name: Bindings
+        run: scripts/build-ios.sh bindings
+
+      - name: Unit tests on the simulator
+        run: scripts/build-ios.sh test
+
+      # SideStore and AltStore re-sign whatever they install with the viewer's
+      # own Apple ID, so the release artifact is unsigned.
+      - name: Unsigned .ipa
+        run: |
+          scripts/build-ios.sh rust
+          scripts/build-ios.sh ipa
+
+      - uses: actions/upload-artifact@v7
+        with:
+          name: ios
+          path: dist/*.ipa
+          if-no-files-found: error

.github/workflows/release.yml

@@ -20,9 +20,6 @@ permissions:
 
 env:
   CARGO_TERM_COLOR: always
-  # Android remains a workflow artifact only until the native libmpv adapter,
-  # corresponding-source bundle, and on-device verification are complete.
-  ANDROID_PUBLIC_RELEASE_ENABLED: 'false'
 
 jobs:
   verify:
@@ -60,11 +57,6 @@ jobs:
           ! grep -q '^\[patch\.crates-io\]' Cargo.toml ||
             { echo "::error::Cargo.toml carries [patch.crates-io]; releases build against the registry"; exit 1; }
 
-      - name: Android publication remains blocked
-        run: |
-          test "$ANDROID_PUBLIC_RELEASE_ENABLED" = false
-          echo "Android APK/AAB publication is blocked until native playback is release-ready."
-
   linux:
     name: Linux artifacts
     needs: verify
@@ -84,7 +76,7 @@ jobs:
       - name: Install build dependencies
         run: |
           sudo apt-get update
-          sudo apt-get install -y libmpv-dev rpm
+          sudo apt-get install -y libmpv-dev libwebkit2gtk-4.1-dev rpm
 
       - name: Gate
         run: |
@@ -148,25 +140,49 @@ jobs:
             dist/*.msi
           if-no-files-found: error
 
+  # The signed APK plus the corresponding source of the libmpv it bundles. The
+  # keystore and its passwords come from the ANDROID_RELEASE_* secrets.
+  android:
+    name: Android
+    needs: verify
+    uses: ./.github/workflows/android.yml
+    with:
+      signed_release: true
+    secrets: inherit
+
+  # The unsigned .ipa: SideStore and AltStore re-sign it with the viewer's own
+  # Apple ID when they install it.
+  ios:
+    name: iOS
+    needs: verify
+    uses: ./.github/workflows/ios.yml
+
   publish:
-    name: Publish desktop artifacts
+    name: Publish
     if: startsWith(github.ref, 'refs/tags/')
-    needs: [linux, windows]
+    needs: [linux, windows, android, ios]
     runs-on: ubuntu-24.04
     permissions:
       contents: write
     steps:
+      # By name: the Android workflow also uploads the AAB, which is for Play
+      # and does not belong on the release.
       - uses: actions/download-artifact@v8
         with:
+          name: linux
+          path: artifacts
+      - uses: actions/download-artifact@v8
+        with:
+          name: windows
+          path: artifacts
+      - uses: actions/download-artifact@v8
+        with:
+          name: android
+          path: artifacts
+      - uses: actions/download-artifact@v8
+        with:
+          name: ios
           path: artifacts
-          merge-multiple: true
-
-      - name: Refuse mobile artifacts while Android publishing is blocked
-        run: |
-          if find artifacts -type f \( -name '*.apk' -o -name '*.aab' \) -print -quit | grep -q .; then
-            echo "::error::Android publishing is disabled while native playback remains incomplete"
-            exit 1
-          fi
 
       - name: Checksums
         run: |

.gitignore

@@ -20,3 +20,9 @@
 /packaging/pkg/
 /packaging/src/
 /packaging/*.pkg.tar.zst
+
+# iOS generated state: XcodeGen owns the project and the Info.plist, and
+# scripts/build-ios.sh writes the bindings and DerivedData under ios/build.
+/ios/build/
+/ios/*.xcodeproj/
+/ios/ProtonStream/Info.plist

Cargo.toml

@@ -11,7 +11,7 @@ members = [
 ]
 
 [workspace.package]
-version = "0.2.0"
+version = "1.6.0"
 edition = "2024"
 license = "MIT"
 repository = "https://github.com/narrrl/proton-stream"
@@ -28,8 +28,8 @@ authors = ["Nils Pukropp <contact@narl.io>"]
 opt-level = 2
 
 [workspace.dependencies]
-proton-sdk = { version = "0.4.0" }
+proton-sdk = { version = "0.7.3" }
-proton-drive-rs = { version = "0.4.0" }
+proton-drive-rs = { version = "0.7.3" }
 
 # Internal crates.
 pstr-core = { path = "crates/pstr-core" }
@@ -51,7 +51,11 @@ anyhow = "1"
 tracing = "0.1"
 tracing-subscriber = { version = "0.3", features = ["env-filter"] }
 directories = "5"
+# Local dates for the history page. Already in the tree through the SDK.
+chrono = { version = "0.4", default-features = false, features = ["clock"] }
 sha2 = "0.10"
+# The id a watch-history file is named by. Already in the tree through the SDK.
+getrandom = "0.3"
 # `bundled` so a Windows build needs no system SQLite.
 rusqlite = { version = "0.32", features = ["bundled"] }
 # The share URL fragment and the custom password are both secrets; they go in
@@ -69,14 +73,22 @@ keyring = { version = "3" }
 clap = { version = "4", features = ["derive"] }
 # The UI. `glow` rather than `wgpu` because step two of the player hands mpv an
 # `MPV_RENDER_API_TYPE_OPENGL` context, and that has to be the same context
-# eframe is drawing into.
+# eframe is drawing into. `accesskit` hands the widget tree to the platform's
+# screen reader (AT-SPI, UI Automation, NSAccessibility).
 eframe = { version = "0.35", default-features = false, features = [
+    "accesskit",
     "default_fonts",
     "glow",
     "wayland",
     "x11",
 ] }
 egui = "0.35"
+# The icons on buttons. Glyphs like ⏭ and 🔊 come out of whichever fallback
+# font has them, at its own size and baseline; an icon font is one set.
+egui-phosphor = { version = "0.13", default-features = false, features = ["regular"] }
+# Tests only: reads the bundled fonts' character maps. The version epaint
+# already builds, so it costs no extra compile.
+skrifa = { version = "0.42", default-features = false, features = ["std"] }
 # Poster thumbnails only: Proton renders them as JPEG, and a decoder that also
 # pulls in every exotic format is weight this app has no use for.
 image = { version = "0.25", default-features = false, features = ["jpeg", "png", "webp"] }
@@ -84,9 +96,28 @@ image = { version = "0.25", default-features = false, features = ["jpeg", "png",
 # behind a poisoned lock for the rest of the session. Same reason
 # `proton-drive-linux` uses it.
 parking_lot = "0.12"
+# Media keys and the desktop's media widget: MPRIS on Linux, SMTC on Windows.
+# `dbus` rather than `zbus` because the keyring's Secret Service store already
+# links libdbus, so this adds no second D-Bus stack.
+souvlaki = { version = "0.8", default-features = false, features = ["use_dbus"] }
+# Holding the screensaver off while a film plays. mpv does that for a window of
+# its own, but the picture here is drawn into ours, and mpv has no window to
+# hold it for.
+dbus = "0.9"
+windows-sys = "0.61"
+# Toasts on Windows. Linux notifications go over the `dbus` above.
+tauri-winrt-notification = "0.8"
+# The exe's own icon resource, which is what Explorer and a taskbar pin draw.
+embed-resource = "3"
+# Proton's CAPTCHA page, which reports success by posting a message to its
+# host, so it needs a webview this app controls. Run in a child process of its
+# own (`pstr-app::verify`): tao and eframe's winit cannot share an event loop.
+# WebKitGTK on Linux, WebView2 on Windows, WKWebView on macOS.
+wry = { version = "0.57", default-features = false, features = ["os-webview"] }
+tao = { version = "0.37", default-features = false, features = ["rwh_06"] }
 rpassword = "7"
 libloading = "0.8"
-lru = "0.12"
+lru = "0.18"
 # `async fn` in traits is stable at MSRV 1.96 but is not dyn-compatible, and the
 # stream layer needs a `dyn` block source so its cache, ring and read-ahead can
 # be tested against a fake without a network or an account.

PLAN.md

@@ -0,0 +1,187 @@
+# Android plan
+
+Where the Android client stands against the desktop app, and what to change to
+make it feel like a modern streaming app rather than a settings form with a
+player attached. Written 2026-10-03 from a source review and four screenshots
+(Library, Title, Shares, Settings) taken on a phone running v0.5.0.
+
+Android last caught up with the desktop on 2026-08-10 (`4ef6225`); the desktop
+gained about twenty features on 2026-10-02 that Android does not have.
+
+## Status (2026-10-03)
+
+Done: section 0, every parity item, and every recommendation in section 2 —
+the Library, Title, Shares, Settings and Downloads redesigns, per-page app
+bars drawn edge to edge, search behind an icon, skeleton loading and
+generated placeholder art, Settings sub-pages and a language picker, a
+long-press Change match, Inter, light and tablet screenshots, the library
+and a title side by side from 840 dp, a poster-to-backdrop shared element
+transition, and predictive back on the title page.
+
+Two departures from the text below. The tablet layout is a two-pane `Row`
+rather than `ListDetailPaneScaffold`, which would have added the
+`adaptive-layout` artifact for one split. Pull to refresh shows the
+indicator while a crawl runs, but not the crawl's progress.
+
+Not yet verified on a device; the host gate (ktlint, unit and screenshot
+tests) passes, and Android lint runs in CI.
+
+A source review on 2026-10-12 found these still short of the text below:
+
+- **Title page.** The backdrop scrolls away with the back button instead of
+  collapsing to a pinned bar, and the icon row has no mark-watched action.
+- **Episode rows** show the file size where runtime was asked for.
+- **Player episode list** is a bottom sheet in landscape too, not a side
+  panel.
+- **Storage** has a usage bar for the streaming cache only; offline episodes
+  have none.
+- **Metadata language** is still a free-text field.
+- **Touch targets.** The player's icons are 40 dp, under the 48 dp floor.
+- **Screenshots** do not cover the player, and only the library is taken at
+  font scale 1.5.
+
+Share rows now say how many files the last crawl found, when it ran and why it
+failed (section 2, Shares), as of the catalog's `share_crawls` table.
+
+## 0. CI (done)
+
+Every `Android` workflow run since August failed in `:app:buildRustHost`:
+`pstr-core` pulls `keyring` → `dbus-secret-service` → `libdbus-sys`, which needs
+`libdbus-1-dev` on the host. Because no run ever succeeded, no cache was ever
+saved, so each run started from nothing.
+
+- `libdbus-1-dev` added to both jobs' apt install.
+- `Swatinem/rust-cache` shares one key between the two jobs and saves on failure.
+- `android/app/build/generated/mpv` is cached on the hash of
+  `scripts/build-libmpv-android.sh`; the script writes a `STAMP` (revision plus
+  its own hash) last and skips the whole libmpv build when the stamp matches.
+
+Later runs also needed meson 1.12.1 from PyPI (noble's 1.3.2 is too old for
+the pinned fontconfig), libmpv built and cached in its own steps so a later
+failure keeps it, and lint's `OldTargetApi` made informational. A cached run
+restores libmpv in under a minute.
+
+## 1. Desktop parity
+
+Ordered by value on a phone.
+
+1. **Open share links from outside the app.** The manifest has only the
+   launcher intent. Add an `ACTION_VIEW` filter for `drive.proton.me/urls/*` and
+   an `ACTION_SEND` (`text/plain`) filter; both open the add-share dialog with
+   the link filled in. Desktop: `4a54af3`, `53a1d0a`.
+2. **Streaming cache budget.** Android runs on the fixed 4 GiB default
+   (`DiskCacheConfig::DEFAULT_BUDGET_BYTES`), large for a phone. Expose
+   `DiskCache::set_budget` through `pstr-android`, add a 1–16 GiB choice with a
+   usage readout under Storage. Desktop: `a432a93`.
+3. **Hardware-decoding switch.** `pstr_mpv.cpp` hard-codes
+   `hwdec=auto-copy-safe`; a device with green frames has no way out. A
+   Settings toggle, applied from the next file.
+4. **Episode list in the player.** A bottom sheet (portrait) or side panel
+   (landscape) with the title's episodes, opened on the playing season and
+   scrolled to the playing episode. Desktop: `7e734db`.
+5. **Long-press menu on tiles.** Play/resume, mark watched or unwatched,
+   download, change match, remove from Continue watching, in a
+   `ModalBottomSheet`. Desktop: `c5808a5`.
+6. **Undo on snackbars** for marking a title and leaving Continue watching.
+   `AppUiState.message` is a bare string today; it needs an action. Desktop:
+   `79c3f68`.
+7. **History tab.** Needs a bridge call over the `pstr-core::library` query
+   the desktop page uses. Desktop: `e7eeaa5`.
+8. **Buffered range on the seek bar** from mpv's `demuxer-cache-time`.
+9. **Up-next card** with the next episode's still and a countdown ring instead
+   of "Up next in 7s" text.
+10. **Featured banner** at the top of the library. Desktop: `7d03736`.
+11. **Bundled Inter** in `ui/theme/Type.kt`, so both clients read the same.
+    Desktop: `558446b`.
+
+## 2. UI recommendations
+
+### Everywhere
+
+- **Colours stay the theme's.** The red is the Persona theme's accent and the
+  card tint comes from the shared palette, so the redesign changes layout and
+  button hierarchy, not colours.
+- **One button hierarchy.** At most one filled accent button per screen;
+  secondary actions tonal or outlined; destructive actions behind a menu and a
+  confirmation, never a filled red button in a list row.
+- **Edge-to-edge, per-screen titles.** The "proton-stream" app bar on every
+  page wastes a band of height. Library uses a collapsing large title; Title
+  pages draw the backdrop under the status bar; other tabs use their name.
+- **Skeletons instead of spinners** for library and title loading, and
+  generated placeholder art (gradient from the accent plus the title's
+  initials) instead of a black card with a play triangle (Akira).
+- **Pull-to-refresh** (`PullToRefreshBox`) replaces the top-bar refresh icon,
+  with crawl progress shown in the indicator area.
+- **Split `ui/ProtonStreamApp.kt`** (1665 lines) into one file per screen
+  before the work below; every item touches it.
+
+### Library
+
+- Poster grid (2:3, `posterUrl`) at three columns on a phone, title under the
+  poster with no card body. The current 210 dp cropped backdrops fit two titles
+  per screen.
+- Continue watching: 16:9 still with the progress bar laid over the bottom
+  edge of the image and "S03E11 · 12 min left" under it.
+- Search becomes an icon in the app bar that expands into an M3 `SearchBar`,
+  instead of a permanent field above everything.
+- Fix "1 episodes" (line ~507; the season header already pluralises).
+
+### Title page
+
+- Full-bleed backdrop with a gradient scrim, poster, title and meta chips
+  (year, score, genres) over it, collapsing as the page scrolls.
+- Synopsis clamped to three lines with "More".
+- One full-width primary button, "Resume S03E11" or "Play S01E01", then a row
+  of icon actions: download, mark watched, and a ⋮ menu holding Start over,
+  Change match and More on AniList. Today five buttons of three styles wrap
+  over three lines.
+- Drop the "Preferred tracks" form and its Save button from this page. The
+  player already remembers tracks by name per title (`d3c5f07`); expose any
+  override from the player's track chooser.
+- Season picker as a dropdown chip or tabs, not stacked accordions; a 40
+  episode title is one long scroll today.
+- Episode rows: 16:9 still with progress overlay, "1 · Mother and Children"
+  (provider name, else "Episode 1") rather than the raw file name
+  `[Judas] Oshi no Ko - S01E01.mkv`, runtime or air date as supporting text,
+  watched and download state as small trailing icons. The red `S01E01` label
+  above each row goes.
+
+### Shares
+
+- `ListItem` rows: name, "12 titles · crawled 2 h ago" or the failure, and a ⋮
+  menu with Refresh, Re-enter link and Remove (confirmed). The current row
+  wraps "Custom password stored securely" over three lines beside three
+  differently styled actions.
+- "Add share" as an extended FAB, which is also where the share-link intent
+  from parity item 1 lands.
+
+### Settings
+
+- Grouped `ListItem` rows (headline, one line of supporting text, trailing
+  switch), with the long explanations moved into the supporting line or an
+  info dialog. Today each toggle carries a paragraph.
+- Split into sub-pages once storage and decoding settings land: Playback,
+  Downloads & storage, Appearance, Metadata, About.
+- Language fields become a picker dialog over a language list, not free text.
+- Storage shows a usage bar (cache, offline episodes) above the budget choice.
+
+### Robustness
+
+- Screenshot tests (Roborazzi, JVM, no device) for each screen in light and
+  dark, phone and tablet, at font scale 1.0 and 1.5 — the redesign changes
+  every screen, and `docs/TESTING.md` has no visual layer today.
+- 48 dp minimum touch targets and content descriptions on the new icon-only
+  actions.
+- Tablet: `ListDetailPaneScaffold` for library + title, since
+  `NavigationSuiteScaffold` already switches to a rail there.
+- Shared-element transition from a poster to its title page, and predictive
+  back.
+
+## Suggested order
+
+1. CI green (section 0).
+2. Split `ProtonStreamApp.kt`; add screenshot tests for the current screens.
+3. Parity 1–3 (small, phone-specific fixes).
+4. Button hierarchy and Inter — every later screen inherits them.
+5. Title page, then Library, then Shares and Settings.
+6. Parity 4–10.

README.md

@@ -24,19 +24,27 @@ layer and the player are done and verified against a real share, and the app has
 a library wall, a page per title with seasons and episodes,
 resume-where-you-left-off, an overlay with a chapter-marked seek bar, a skip
 button for openings and endings, next/previous episode with an "up next"
-countdown, optional metadata, themes and share management. What is left is mostly sidecar subtitle files
+countdown, subtitle files beside the video, optional metadata, themes and share
-(`.srt`/`.ass` beside the video are invisible to the crawl today) and running the
+management. What is left is mostly running the macOS packaging on a real Mac. See
-macOS packaging on a real Mac. See `docs/DEVELOPMENT.md`.
+`docs/DEVELOPMENT.md`.
 
 A native Android 12+ client is under `android/`, sharing the Rust catalog and
 streaming implementation through UniFFI. It features a modern Material 3 interface,
 an immersive fullscreen player with auto-hiding controls, and offline downloads.
 Its toolchain, emulator, signing, and release instructions are in [`docs/ANDROID.md`](docs/ANDROID.md).
 
+An iOS 17+ client under `ios/` is a SwiftUI port of the Android one over the same
+Rust engine, built as an unsigned `.ipa` for SideStore or AltStore; see
+[`docs/IOS.md`](docs/IOS.md).
+
 ```bash
 cargo run --release -p pstr-app          # the app
+proton-stream 'https://drive.proton.me/urls/TOKEN#fragment'   # open the Add form with a link
 ```
 
+One window at a time: a second launch brings the open window forward and
+hands it any share link it was given, then exits.
+
 The `pstr` CLI does the same work headlessly, and is what tells you which layer
 is broken:
 
@@ -67,9 +75,9 @@ against the SDK's own range download.
 | Player | Embedded libmpv, drawing into the app's own GL surface: HEVC 10-bit, HDR and ASS subtitles with hardware decode. Volume, audio-track, subtitle and chapter pickers; skip-the-opening; next/previous episode and autoplay. The language picked is preferred for the next file too. |
 | Transcoding | None. mpv demuxes and decodes natively. |
 | UI | egui/eframe on glow; mpv renders into the same GL context. |
-| Themes | The shipped near-black palette plus Catppuccin Latte, Frappé, Macchiato and Mocha, each with a choice of eight accents — pink and sky among them — drawn as a gradient unless you turn that off. Picked on the Shares page, applied without a restart. |
+| Themes | The shipped near-black palette, Catppuccin Latte, Frappé, Macchiato and Mocha, and a Persona 5 one — black, white and one loud red, which is what the Red accent is there for — each with a choice of nine accents, drawn as a gradient unless you turn that off. Picked on the Settings page, applied without a restart. |
-| Metadata | Filename parsing, with optional AniList/TMDB enrichment — **off by default**, because enabling it sends your library's titles to a third party. It brings posters, synopses and per-episode titles; a title the scorer refuses to guess about can be pinned by hand, and a pinned match is never overwritten. |
+| Metadata | Filename parsing, with optional AniList/TMDB enrichment — **off by default**, because enabling it sends your library's titles to a third party. It brings posters, synopses, fanart and per-episode titles and synopses (for AniList, from ani.zip, which is sent the matched ids); a title the scorer refuses to guess about can be pinned by hand, and a pinned match is never overwritten. The library sorts by name, watch, add or air date, rating and popularity, folds a franchise into one tile, and shelves titles by director, studio and genre. See [docs/METADATA.md](docs/METADATA.md). |
-| Platforms | Linux and Windows; macOS packaging is written but has not been run on a Mac. A native Android 12+ client is available featuring a Material 3 UI and immersive fullscreen playback. |
+| Platforms | Linux and Windows; macOS packaging is written but has not been run on a Mac. A native Android 12+ client is available featuring a Material 3 UI and immersive fullscreen playback, and an iOS 17+ port of it for sideloading. |
 
 ## Building
 
@@ -79,7 +87,9 @@ Rust 2024, MSRV 1.96.
 cargo build --release
 ```
 
-`pstr-player` needs libmpv development headers (`mpv` ≥ 2.0). On Windows those
+`pstr-player` needs libmpv development headers (`mpv` ≥ 2.0), and on Linux
+`pstr-app` needs WebKitGTK 4.1's, for the window Proton's CAPTCHA is shown in.
+On Windows the libmpv ones
 come from the separate **mpv-dev** archive rather than mpv's player build, and
 `libmpv-2.dll` ships next to the executable. The Proton SDK crates come from
 crates.io; nothing here builds against a sibling checkout.
@@ -93,6 +103,9 @@ Android builds use JDK 17, Android SDK 36/NDK 28, Gradle 8.13, `cargo-ndk`, and
 UniFFI. Run `bash scripts/build-android.sh debug` after installing that toolchain;
 see [`docs/ANDROID.md`](docs/ANDROID.md) for exact setup and release signing.
 
+iOS builds need macOS with Xcode, XcodeGen and the `aarch64-apple-ios` Rust
+target: `scripts/build-ios.sh all` writes `dist/proton-stream-<version>-ios.ipa`.
+
 ## Privacy
 
 - The share URL fragment **is** the decryption password. It and any custom
@@ -103,11 +116,22 @@ see [`docs/ANDROID.md`](docs/ANDROID.md) for exact setup and release signing.
   a local HTTP server: there is no port for another process on the machine to ask
   for the plaintext, and mpv is handed an opaque token rather than a URL that
   would put a share secret in its log and window title.
-- The block cache holds decrypted content. It lives in your cache directory and
+- The block cache holds decrypted content. It lives in your cache directory,
-  can be deleted at any time the app is not running.
+  can be deleted at any time the app is not running, and can be sized or
+  emptied from Settings → Storage.
+- A share link given as a command-line argument is visible to other users of
+  the machine in the process list while that launch runs, and may land in
+  shell history. Pasting it into the window (Ctrl+V) does neither.
+- The desktop's media widget is handed the title, the episode and a `file://`
+  path to artwork already on disk — never a provider URL, so the shell never
+  contacts a metadata provider on its own.
 
 ## License
 
-The shared Rust crates and desktop application are MIT licensed. The Android
+The shared Rust crates and desktop application are MIT licensed. The Android and
-application and its combined native distribution are GPL-3.0-or-later; see
+iOS applications and their combined native distributions are GPL-3.0-or-later; see
-[`android/LICENSE.md`](android/LICENSE.md) and the bundled-component notices.
+[`android/LICENSE.md`](android/LICENSE.md), [`ios/LICENSE.md`](ios/LICENSE.md) and
+the bundled-component notices.
+The desktop application embeds the Inter typeface, under the SIL Open Font
+License 1.1 ([`crates/pstr-app/assets/fonts/Inter-OFL.txt`](crates/pstr-app/assets/fonts/Inter-OFL.txt)),
+and the Phosphor icon font, under MIT.

android/.editorconfig

@@ -0,0 +1,29 @@
+# ktlint configuration.
+#
+# The whole standard ruleset is off, and rules are enabled one at a time. That
+# is deliberate: turning it all on reports ~540 findings on the existing tree,
+# almost all of them line-wrapping preference, and a mechanical reformat of
+# every file would bury the changes that matter in review. The rules kept here
+# are the ones whose violation is a defect or a real maintenance cost rather
+# than a matter of taste — starting with the unused imports that were the
+# evidence no gate ran at all.
+#
+# Adding a rule is cheap. Do it with the reformat it implies in its own commit.
+
+[*.{kt,kts}]
+ktlint_standard = disabled
+ktlint_standard_no-unused-imports = enabled
+ktlint_standard_no-wildcard-imports = enabled
+ktlint_standard_no-semi = enabled
+ktlint_standard_no-trailing-spaces = enabled
+ktlint_standard_no-consecutive-blank-lines = enabled
+ktlint_standard_no-empty-file = enabled
+ktlint_standard_final-newline = enabled
+ktlint_standard_filename = enabled
+ktlint_standard_no-line-break-before-assignment = enabled
+ktlint_standard_no-multi-spaces = enabled
+
+# Vendored from rustls-platform-verifier. Restyling it would turn the next sync
+# with upstream into a merge conflict for no benefit.
+[**/org/rustls/**.kt]
+ktlint = disabled

android/THIRD_PARTY_NOTICES.md

@@ -7,11 +7,12 @@ distributions.
 | Component | License |
 |---|---|
 | mpv/libmpv | GPL-2.0-or-later by default; verify the pinned build configuration |
-| LLVM libc++ shared runtime (Android NDK r29) | Apache-2.0 WITH LLVM-exception |
+| LLVM libc++ shared runtime (Android NDK r30) | Apache-2.0 WITH LLVM-exception |
 | AndroidX and Jetpack Compose | Apache-2.0 |
 | Kotlin | Apache-2.0 |
 | JNA | Apache-2.0 or LGPL-2.1-or-later |
 | UniFFI | MPL-2.0 |
+| Inter typeface (bundled, `Inter-OFL.txt`) | OFL-1.1 |
 | proton-stream shared Rust crates | MIT |
 
 This summary is not a replacement for dependency license files. Before a

android/app/build.gradle.kts

@@ -5,6 +5,8 @@ plugins {
     alias(libs.plugins.android.application)
     alias(libs.plugins.kotlin.android)
     alias(libs.plugins.kotlin.compose)
+    alias(libs.plugins.ktlint)
+    alias(libs.plugins.roborazzi)
 }
 
 val repositoryRoot = rootProject.projectDir.parentFile
@@ -45,7 +47,7 @@ android {
     namespace = "io.narl.protonstream"
     compileSdk = 36
     buildToolsVersion = "37.0.0"
-    ndkVersion = "29.0.14206865"
+    ndkVersion = "30.0.16248370"
 
     defaultConfig {
         applicationId = "io.narl.protonstream"
@@ -53,6 +55,7 @@ android {
         targetSdk = 36
         versionCode = releaseVersionCode
         versionName = releaseVersionName
+        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
 
         ndk {
             abiFilters += listOf("arm64-v8a", "x86_64")
@@ -103,7 +106,54 @@ android {
             isMinifyEnabled = true
             isShrinkResources = true
             if (releaseStore != null) signingConfig = signingConfigs.getByName("release")
-            proguardFiles(getDefaultProguardFile("proguard-android-optimize.txt"), "proguard-rules.pro")
+            proguardFiles(
+                getDefaultProguardFile("proguard-android-optimize.txt"),
+                "proguard-rules.pro",
+                // Applied to the shipping APK on purpose; the file explains the
+                // trade-off and what each keep is repairing.
+                "proguard-instrumentation.pro",
+            )
+            testProguardFiles("proguard-test-rules.pro")
+        }
+    }
+
+    // The minified path is what ships, and R8 breaks reflective UniFFI/JNA
+    // surfaces in ways no debug run can see. CI sets this to `release` and runs
+    // connectedAndroidTest against it; locally the default keeps builds fast.
+    testBuildType = providers.environmentVariable("ANDROID_TEST_BUILD_TYPE").orNull ?: "debug"
+
+    lint {
+        warningsAsErrors = true
+        abortOnError = true
+        checkDependencies = true
+        // The baseline records what was already here when the gate went in, so
+        // anything *new* fails. It is not a permanent exemption: every entry in
+        // it maps to an open bug in docs/BUGS.md (the SharedPreferences
+        // `commit()` calls are B20, the PiP one is B40), and the file should get
+        // shorter as those land. Regenerate with `gradlew updateLintBaseline`
+        // after a fix, and never to make an unrelated failure go away.
+        baseline = file("lint-baseline.xml")
+        // Generated UniFFI bindings are not ours to fix.
+        disable += setOf("UnusedIds")
+        // Dependency freshness is not a defect, and as errors these break the
+        // gate whenever someone else cuts a release. Upgrades are a deliberate
+        // act with their own verification; `gradlew lintDebug -Dlint...` or a
+        // dependency bot is the right place to surface them, not CI.
+        informational += setOf(
+            "GradleDependency",
+            "NewerVersionAvailable",
+            "AndroidGradlePluginVersion",
+            // The same for the platform: raising targetSdk opts into new
+            // behaviour and needs its own pass on a device.
+            "OldTargetApi",
+        )
+        sarifReport = true
+    }
+
+    testOptions {
+        unitTests {
+            isIncludeAndroidResources = true
+            isReturnDefaultValues = true
         }
     }
 
@@ -130,20 +180,16 @@ val uniffiSourceDir = layout.buildDirectory.dir("generated/source/uniffi")
 val hostRustLibrary = repositoryRoot.resolve(
     "target/debug/${System.mapLibraryName("pstr_android")}",
 )
-val stagedMpvDir = layout.buildDirectory.dir("generated/mpv")
 
 val buildLibmpvAndroid by tasks.registering(Exec::class) {
     group = "native"
     description = "Builds the pinned GPL libmpv and stages both Android ABIs."
     workingDir(repositoryRoot)
     commandLine("bash", repositoryRoot.resolve("scripts/build-libmpv-android.sh").absolutePath)
-    inputs.file(repositoryRoot.resolve("scripts/build-libmpv-android.sh"))
+    // No declared outputs: the script's STAMP is the up-to-date check. Gradle
-    outputs.files(
+    // deletes the declared outputs of a task it has no history for, which on a
-        stagedMpvDir.map { it.file("jniLibs/arm64-v8a/libmpv.so") },
+    // fresh CI checkout threw away the tree just restored from the cache and
-        stagedMpvDir.map { it.file("jniLibs/x86_64/libmpv.so") },
+    // rebuilt libmpv from source on every run.
-        stagedMpvDir.map { it.file("include/mpv/client.h") },
-        stagedMpvDir.map { it.file("REVISION") },
-    )
 }
 
 val buildRustHost by tasks.registering(Exec::class) {
@@ -209,7 +255,6 @@ dependencies {
     implementation(libs.androidx.work.runtime)
     implementation(libs.jna) { artifact { type = "aar" } }
 
-
     implementation(platform(libs.androidx.compose.bom))
     implementation(libs.androidx.compose.ui)
     implementation(libs.androidx.compose.ui.tooling.preview)
@@ -219,5 +264,48 @@ dependencies {
     implementation(libs.androidx.compose.material3.adaptive)
     implementation(libs.androidx.compose.material3.navigation.suite)
     debugImplementation(libs.androidx.compose.ui.tooling)
+
     testImplementation(libs.junit)
+    testImplementation(libs.robolectric)
+    testImplementation(libs.androidx.test.core)
+    testImplementation(libs.androidx.work.testing)
+    testImplementation(platform(libs.androidx.compose.bom))
+    testImplementation(libs.androidx.compose.ui.test.junit4)
+    testImplementation(libs.roborazzi)
+    testImplementation(libs.roborazzi.compose)
+    testImplementation(libs.roborazzi.junit.rule)
+
+    androidTestImplementation(libs.androidx.test.junit)
+    androidTestImplementation(libs.androidx.test.core)
+    androidTestImplementation(libs.androidx.test.runner)
+    androidTestImplementation(libs.androidx.work.testing)
+    androidTestImplementation(platform(libs.androidx.compose.bom))
+    androidTestImplementation(libs.androidx.compose.ui.test.junit4)
+    debugImplementation(libs.androidx.compose.ui.test.manifest)
 }
+
+ktlint {
+    version.set("1.5.0")
+    android.set(true)
+    ignoreFailures.set(false)
+    filter {
+        // UniFFI writes these; they are regenerated on every build.
+        exclude { it.file.path.contains("${File.separator}generated${File.separator}") }
+        // Vendored from rustls-platform-verifier. Restyling it would make the
+        // next sync with upstream a merge conflict for no benefit.
+        exclude { it.file.path.contains("${File.separator}org${File.separator}rustls${File.separator}") }
+    }
+}
+
+// Screenshot baselines live beside the tests that draw them, so a change to how
+// a screen looks shows up in review as a changed image. `recordRoborazziDebug`
+// rewrites them; `verifyRoborazziDebug` fails on any difference.
+roborazzi {
+    outputDir.set(file("src/test/screenshots"))
+}
+
+// The generated UniFFI directory is a main source dir, so ktlint reads it even
+// though the filter above drops every file in it. Without this, Gradle refuses
+// the build for an undeclared dependency between the two tasks.
+tasks.matching { it.name.startsWith("runKtlintCheckOver") || it.name.startsWith("runKtlintFormatOver") }
+    .configureEach { dependsOn(generateUniFfiBindings) }

android/app/lint-baseline.xml

@@ -0,0 +1,268 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<issues format="6" by="lint 8.13.2" type="baseline" client="gradle" dependencies="true" name="AGP (8.13.2)" variant="all" version="8.13.2">
+
+    <issue
+        id="AndroidGradlePluginVersion"
+        message="A newer version of com.android.application than 8.13.2 is available: 9.3.1"
+        errorLine1="agp = &quot;8.13.2&quot;"
+        errorLine2="      ~~~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="2"
+            column="7"/>
+    </issue>
+
+    <issue
+        id="GradleDependency"
+        message="A newer version of androidx.compose:compose-bom than 2026.06.00 is available: 2026.06.01"
+        errorLine1="compose-bom = &quot;2026.06.00&quot;"
+        errorLine2="              ~~~~~~~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="4"
+            column="15"/>
+    </issue>
+
+    <issue
+        id="GradleDependency"
+        message="A newer version of androidx.activity:activity-compose than 1.11.0 is available: 1.13.0"
+        errorLine1="activity = &quot;1.11.0&quot;"
+        errorLine2="           ~~~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="5"
+            column="12"/>
+    </issue>
+
+    <issue
+        id="GradleDependency"
+        message="A newer version of androidx.lifecycle:lifecycle-runtime-ktx than 2.9.4 is available: 2.11.0"
+        errorLine1="lifecycle = &quot;2.9.4&quot;"
+        errorLine2="            ~~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="6"
+            column="13"/>
+    </issue>
+
+    <issue
+        id="GradleDependency"
+        message="A newer version of androidx.lifecycle:lifecycle-viewmodel-compose than 2.9.4 is available: 2.11.0"
+        errorLine1="lifecycle = &quot;2.9.4&quot;"
+        errorLine2="            ~~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="6"
+            column="13"/>
+    </issue>
+
+    <issue
+        id="GradleDependency"
+        message="A newer version of androidx.navigation:navigation-compose than 2.9.5 is available: 2.9.8"
+        errorLine1="navigation = &quot;2.9.5&quot;"
+        errorLine2="             ~~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="7"
+            column="14"/>
+    </issue>
+
+    <issue
+        id="GradleDependency"
+        message="A newer version of androidx.work:work-runtime-ktx than 2.10.5 is available: 2.11.2"
+        errorLine1="work = &quot;2.10.5&quot;"
+        errorLine2="       ~~~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="8"
+            column="8"/>
+    </issue>
+
+    <issue
+        id="GradleDependency"
+        message="A newer version of androidx.work:work-testing than 2.10.5 is available: 2.11.2"
+        errorLine1="work = &quot;2.10.5&quot;"
+        errorLine2="       ~~~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="8"
+            column="8"/>
+    </issue>
+
+    <issue
+        id="GradleDependency"
+        message="A newer version of androidx.compose.material3.adaptive:adaptive than 1.1.0 is available: 1.2.0"
+        errorLine1="adaptive = &quot;1.1.0&quot;"
+        errorLine2="           ~~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="9"
+            column="12"/>
+    </issue>
+
+    <issue
+        id="GradleDependency"
+        message="A newer version of androidx.compose.material3:material3-adaptive-navigation-suite than 1.1.0 is available: 1.4.0"
+        errorLine1="adaptive = &quot;1.1.0&quot;"
+        errorLine2="           ~~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="9"
+            column="12"/>
+    </issue>
+
+    <issue
+        id="GradleDependency"
+        message="A newer version of androidx.core:core-ktx than 1.17.0 is available: 1.19.0"
+        errorLine1="androidx-core = { module = &quot;androidx.core:core-ktx&quot;, version = &quot;1.17.0&quot; }"
+        errorLine2="                                                               ~~~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="19"
+            column="64"/>
+    </issue>
+
+    <issue
+        id="NewerVersionAvailable"
+        message="A newer version of org.jetbrains.kotlin.android than 2.2.21 is available: 2.4.10"
+        errorLine1="kotlin = &quot;2.2.21&quot;"
+        errorLine2="         ~~~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="3"
+            column="10"/>
+    </issue>
+
+    <issue
+        id="NewerVersionAvailable"
+        message="A newer version of org.jetbrains.kotlin.plugin.compose than 2.2.21 is available: 2.4.10"
+        errorLine1="kotlin = &quot;2.2.21&quot;"
+        errorLine2="         ~~~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="3"
+            column="10"/>
+    </issue>
+
+    <issue
+        id="NewerVersionAvailable"
+        message="A newer version of net.java.dev.jna:jna than 5.17.0 is available: 5.19.1"
+        errorLine1="jna = &quot;5.17.0&quot;"
+        errorLine2="      ~~~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="10"
+            column="7"/>
+    </issue>
+
+    <issue
+        id="NewerVersionAvailable"
+        message="A newer version of org.robolectric:robolectric than 4.16 is available: 4.16.1"
+        errorLine1="robolectric = &quot;4.16&quot;"
+        errorLine2="              ~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="12"
+            column="15"/>
+    </issue>
+
+    <issue
+        id="NewerVersionAvailable"
+        message="A newer version of org.jlleitschuh.gradle.ktlint than 13.1.0 is available: 14.2.0"
+        errorLine1="ktlint-plugin = &quot;13.1.0&quot;"
+        errorLine2="                ~~~~~~~~">
+        <location
+            file="../gradle/libs.versions.toml"
+            line="16"
+            column="17"/>
+    </issue>
+
+    <issue
+        id="ObsoleteSdkInt"
+        message="Unnecessary; `SDK_INT` is always >= 31"
+        errorLine1="        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {"
+        errorLine2="            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~">
+        <location
+            file="src/main/kotlin/org/rustls/platformverifier/CertificateVerifier.kt"
+            line="294"
+            column="13"/>
+    </issue>
+
+    <issue
+        id="AutoboxingStateCreation"
+        message="Prefer `mutableIntStateOf` instead of `mutableStateOf`"
+        errorLine1="    var remaining by remember(next?.linkId) { mutableStateOf(UP_NEXT_SECONDS) }"
+        errorLine2="                                              ~~~~~~~~~~~~~~">
+        <location
+            file="src/main/java/io/narl/protonstream/playback/PlayerScreen.kt"
+            line="707"
+            column="47"/>
+    </issue>
+
+    <issue
+        id="UseKtx"
+        message="Use the KTX extension function `SharedPreferences.edit` instead?"
+        errorLine1="        check(preferences.edit().putString(key, Base64.encodeToString(payload, Base64.NO_WRAP)).commit())"
+        errorLine2="              ~~~~~~~~~~~~~~~~~~">
+        <location
+            file="src/main/java/io/narl/protonstream/native/KeystoreSecretStore.kt"
+            line="41"
+            column="15"/>
+    </issue>
+
+    <issue
+        id="UseKtx"
+        message="Use the KTX extension function `SharedPreferences.edit` instead?"
+        errorLine1="        check(preferences.edit().remove(key).commit())"
+        errorLine2="              ~~~~~~~~~~~~~~~~~~">
+        <location
+            file="src/main/java/io/narl/protonstream/native/KeystoreSecretStore.kt"
+            line="64"
+            column="15"/>
+    </issue>
+
+    <issue
+        id="UseKtx"
+        message="Use the KTX extension function `SharedPreferences.edit` instead?"
+        errorLine1="        set(value) { preferences.edit().putBoolean(KEY_WIFI_ONLY, value).apply() }"
+        errorLine2="                     ~~~~~~~~~~~~~~~~~~">
+        <location
+            file="src/main/java/io/narl/protonstream/settings/SettingsStore.kt"
+            line="10"
+            column="22"/>
+    </issue>
+
+    <issue
+        id="UseKtx"
+        message="Use the KTX extension function `SharedPreferences.edit` instead?"
+        errorLine1="        set(value) { preferences.edit().putBoolean(KEY_BACKGROUND_AUDIO, value).apply() }"
+        errorLine2="                     ~~~~~~~~~~~~~~~~~~">
+        <location
+            file="src/main/java/io/narl/protonstream/settings/SettingsStore.kt"
+            line="14"
+            column="22"/>
+    </issue>
+
+    <issue
+        id="UseKtx"
+        message="Use the KTX extension function `SharedPreferences.edit` instead?"
+        errorLine1="        set(value) { preferences.edit().putBoolean(KEY_AUTO_SKIP, value).apply() }"
+        errorLine2="                     ~~~~~~~~~~~~~~~~~~">
+        <location
+            file="src/main/java/io/narl/protonstream/settings/SettingsStore.kt"
+            line="25"
+            column="22"/>
+    </issue>
+
+    <issue
+        id="UseKtx"
+        message="Use the KTX extension function `SharedPreferences.edit` instead?"
+        errorLine1="        set(value) { preferences.edit().putBoolean(KEY_AUTOPLAY, value).apply() }"
+        errorLine2="                     ~~~~~~~~~~~~~~~~~~">
+        <location
+            file="src/main/java/io/narl/protonstream/settings/SettingsStore.kt"
+            line="30"
+            column="22"/>
+    </issue>
+
+</issues>

android/app/proguard-instrumentation.pro

@@ -0,0 +1,98 @@
+# Keeps that exist so the instrumentation suite can run against the *release*
+# build. They are applied to the shipping APK, which is a real trade-off worth
+# stating plainly: the tested artifact is not byte-identical to an artifact
+# built without them.
+#
+# It is the better side of the trade. The alternative is to run instrumentation
+# against `debug` only, which leaves R8 — the step that has already broken this
+# app twice, in ways no debug run can reproduce — entirely uncovered. What is
+# kept here is a few kilobytes of framework plumbing containing no application
+# logic and revealing nothing about the app.
+#
+# Why these keeps are needed at all: the instrumentation APK is minified in a
+# separate R8 run that consumes the app's mapping file, and links against the
+# app's classes at runtime. That arrangement fails in two ways.
+#
+# 1. The mapping file carries renames but not R8's parameter-permutation
+#    optimisation, so a permuted method resolves to the wrong descriptor from
+#    the test APK.
+# 2. A class that only the test APK reaches is unreachable from the app's call
+#    graph, so R8 removes it from the app APK — and the test APK does not
+#    bundle it, because it is supposed to come from the app.
+
+# The Kotlin runtime is where both failures land, because androidx.test is
+# itself Kotlin and shares the app's copy of the stdlib. Keeping it wholesale
+# rather than class by class is deliberate: each individual keep only moves the
+# crash to the next facade the runner happens to touch, which is a list nobody
+# can enumerate ahead of time. Three were hit before this rule replaced them:
+#
+#   NoSuchMethodError: No static method f(Ljava/lang/Object;Ljava/lang/String;)V
+#     in class Lo6/k;                     (o6.k = kotlin.jvm.internal.Intrinsics,
+#                                          whose parameters R8 had permuted —
+#                                          every Kotlin class calls it on entry,
+#                                          so nothing ran at all)
+#   NoClassDefFoundError: Lkotlin/LazyKt;  (androidx.test.platform.io.TestDirCalculator)
+#
+# Cost is roughly a megabyte of dex against a ~100 MB APK that is almost
+# entirely native libraries.
+-keep class kotlin.** { *; }
+
+# `AndroidJUnitRunner.onCreate` traces its own startup. Nothing in the app
+# reaches androidx.tracing, so R8 dropped it and the runner could not start:
+#
+#   java.lang.NoClassDefFoundError: Failed resolution of: Landroidx/tracing/Trace;
+#   at androidx.test.runner.AndroidJUnitRunner.onCreate(AndroidJUnitRunner.java:307)
+-keep class androidx.tracing.** { *; }
+
+# A third shape of the same problem, and the one worth understanding: the app
+# only ever touches WorkManager through its implementation, so R8 vertically
+# merged the abstract `androidx.work.WorkManager` into `WorkManagerImpl` and the
+# abstract type stopped existing. It is absent from mapping.txt entirely rather
+# than renamed. The download tests declare fields of the public types, so JUnit's
+# field scan could not even construct the test class:
+#
+#   java.lang.NoClassDefFoundError: Failed resolution of: Landroidx/work/WorkManager;
+#   at org.junit.runners.model.TestClass.getSortedDeclaredFields(TestClass.java:77)
+#
+# Kept package-wide because the same merge can happen to any of the public API
+# types the tests name (WorkInfo, Data, Constraints), and finding out one crash
+# at a time costs a four-minute device round trip each.
+-keep class androidx.work.** { *; }
+
+# Everything above is framework plumbing. The last group is app code, and it is
+# the one keep in this file that costs real fidelity: R8 no longer optimises
+# these classes in the shipping build, so the suite no longer proves R8 handles
+# them correctly. It is a narrow loss — the surfaces R8 has actually
+# broken here are the FFI ones, and those are kept for functional reasons in
+# proguard-rules.pro and stay under test.
+#
+# The trigger was `DownloadStateStore.clear()`. It is not dead code — AppViewModel
+# calls it — but it has exactly one call site, so R8 inlined it and dropped the
+# method. Only a caller that resolves it by name, which is to say a test, notices:
+#
+#   java.lang.NoSuchMethodError: No virtual method clear()V
+#   in class Lio/narl/protonstream/download/c;
+#
+# Package-wide rather than class-by-class: Kotlin's top-level functions live in
+# a synthesised `...Kt` facade that no source file names, so keeping the classes
+# a test imports still leaves it missing `DownloadCoordinatorKt`.
+-keep class io.narl.protonstream.download.** { *; }
+
+# Same inlining, one layer out: the `wifiOnly` setter behind the download
+# constraint.
+#   java.lang.NoSuchMethodError: No virtual method setWifiOnly(Z)V in class Li5/a;
+-keep class io.narl.protonstream.settings.SettingsStore { *; }
+
+# The live cases drive the player directly, so the same inlining applies to the
+# playback classes they name.
+-keep class io.narl.protonstream.playback.** { *; }
+
+# `runBlocking` — the live cases drive suspending bridge calls from a JUnit
+# thread. The app itself never blocks a thread on a coroutine, so R8 drops the
+# facade that holds it:
+#
+#   java.lang.NoClassDefFoundError: Failed resolution of: Lkotlinx/coroutines/BuildersKt;
+#
+# Kept narrowly rather than as `kotlinx.coroutines.**`: that library is large and
+# on the app's hot paths, and pinning all of it would cost real optimisation.
+-keep class kotlinx.coroutines.BuildersKt** { *; }

android/app/proguard-rules.pro

@@ -7,3 +7,19 @@
 -keepclasseswithmembernames class * {
     native <methods>;
 }
+
+# UniFFI records are Kotlin data classes whose generic signatures and
+# annotations survive into the runtime; stripping them changes how the bindings
+# lift and lower structured types.
+-keepattributes Signature,*Annotation*,InnerClasses,EnclosingMethod
+
+# JNA dispatches into callbacks reflectively by method name.
+-keepclassmembers class * implements com.sun.jna.Callback {
+    <methods>;
+}
+
+# The bridge calls back into these from Rust. Nothing in the Kotlin call graph
+# reaches their overrides, so R8 is free to rename or drop them.
+-keep class io.narl.protonstream.native.KeystoreSecretStore { *; }
+-keep class * implements uniffi.pstr_android.AndroidSecretStore { *; }
+-keep class * implements uniffi.pstr_android.DownloadObserver { *; }

android/app/proguard-test-rules.pro

@@ -0,0 +1,11 @@
+# Applied only to the instrumentation APK when androidTest runs against a
+# minified build (ANDROID_TEST_BUILD_TYPE=release). The tests exist to prove the
+# *app's* R8 configuration is right, so nothing here may relax the app's rules —
+# it only keeps the test harness itself intact.
+-dontobfuscate
+-keep class io.narl.protonstream.** { *; }
+-keep class androidx.test.** { *; }
+-dontwarn androidx.test.**
+-keepclasseswithmembers class * {
+    @org.junit.Test <methods>;
+}

android/app/src/androidTest/java/io/narl/protonstream/download/DownloadCoordinatorInstrumentedTest.kt

@@ -0,0 +1,129 @@
+package io.narl.protonstream.download
+
+import android.content.Context
+import androidx.test.core.app.ApplicationProvider
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.work.Configuration
+import androidx.work.NetworkType
+import androidx.work.WorkInfo
+import androidx.work.WorkManager
+import androidx.work.testing.SynchronousExecutor
+import androidx.work.testing.WorkManagerTestInitHelper
+import io.narl.protonstream.settings.SettingsStore
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNotNull
+import org.junit.Assert.assertTrue
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+
+/**
+ * What actually reaches WorkManager. The unit tests cover the pure helpers; this
+ * covers the enqueue itself — the input data (which is persisted unencrypted, so
+ * it must carry no secret), the constraints, and the unique-work identity that
+ * pause and resume depend on.
+ */
+@RunWith(AndroidJUnit4::class)
+class DownloadCoordinatorInstrumentedTest {
+    private lateinit var context: Context
+    private lateinit var workManager: WorkManager
+
+    @Before
+    fun setUp() {
+        context = ApplicationProvider.getApplicationContext()
+        WorkManagerTestInitHelper.initializeTestWorkManager(
+            context,
+            Configuration.Builder().setExecutor(SynchronousExecutor()).build(),
+        )
+        workManager = WorkManager.getInstance(context)
+        workManager.cancelAllWork().result.get()
+        DownloadStateStore(context).clear()
+    }
+
+    private fun download(linkId: String = "link-1", shareId: String = "share-1") = RetainedDownload(
+        shareId = shareId,
+        volumeId = "volume-1",
+        linkId = linkId,
+        label = "S01E01.mkv",
+    )
+
+    private fun infoFor(download: RetainedDownload): WorkInfo? =
+        workManager.getWorkInfosForUniqueWork(
+            DownloadCoordinator.workName(download.shareId, download.linkId),
+        ).get().firstOrNull()
+
+    @Test
+    fun resumingEnqueuesUniqueWorkAndRetainsAQueuedRecord() {
+        val download = download()
+        DownloadCoordinator.resume(context, download)
+
+        assertNotNull(infoFor(download))
+        assertEquals(
+            RetainedDownload.STATUS_QUEUED,
+            DownloadStateStore(context).get("share-1", "link-1")?.status,
+        )
+    }
+
+    /**
+     * Tags are persisted in `androidx.work.workdb` unencrypted and are what the
+     * UI queries and what cancel-by-share matches on. Pinning the exact set is
+     * what makes an accidental addition — a fragment, a URL — visible in review.
+     */
+    @Test
+    fun theWorkCarriesExactlyTheExpectedTags() {
+        val download = download()
+        DownloadCoordinator.resume(context, download)
+
+        val tags = infoFor(download)?.tags.orEmpty()
+        assertTrue(DownloadCoordinator.TAG in tags)
+        assertTrue(DownloadCoordinator.shareTag("share-1") in tags)
+        assertTrue("${DownloadCoordinator.EPISODE_TAG}S01E01.mkv" in tags)
+        // The remaining tag is WorkManager's own worker class name.
+        assertEquals(4, tags.size)
+    }
+
+    @Test
+    fun theWifiOnlySettingReachesTheConstraint() {
+        // Documents B29: the constraint is read at enqueue time, so work already
+        // queued keeps whatever was set when it was queued. When B29 is fixed,
+        // this test grows a case for flipping the toggle after enqueue.
+        SettingsStore(context).wifiOnly = true
+        assertEquals(NetworkType.UNMETERED, requiredNetworkType(SettingsStore(context).wifiOnly))
+        SettingsStore(context).wifiOnly = false
+        assertEquals(NetworkType.CONNECTED, requiredNetworkType(SettingsStore(context).wifiOnly))
+    }
+
+    @Test
+    fun pauseCancelsTheWorkAndRecordsThePausedStatus() {
+        val download = download()
+        DownloadCoordinator.resume(context, download)
+        DownloadCoordinator.pause(context, download)
+
+        assertTrue(infoFor(download)?.state?.isFinished ?: false)
+        assertEquals(
+            RetainedDownload.STATUS_PAUSED,
+            DownloadStateStore(context).get("share-1", "link-1")?.status,
+        )
+    }
+
+    @Test
+    fun cancellingOneShareLeavesAnotherSharesWorkAlone() {
+        val first = download(linkId = "a", shareId = "share-1")
+        val second = download(linkId = "b", shareId = "share-2")
+        DownloadCoordinator.resume(context, first)
+        DownloadCoordinator.resume(context, second)
+
+        workManager.cancelAllWorkByTag(DownloadCoordinator.shareTag("share-1")).result.get()
+
+        assertTrue(infoFor(first)?.state?.isFinished ?: false)
+        assertEquals(WorkInfo.State.ENQUEUED, infoFor(second)?.state)
+    }
+
+    @Test
+    fun twoEpisodesOfOneShareEnqueueSeparately() {
+        DownloadCoordinator.resume(context, download(linkId = "a"))
+        DownloadCoordinator.resume(context, download(linkId = "b"))
+
+        assertEquals(2, workManager.getWorkInfosByTag(DownloadCoordinator.TAG).get().size)
+    }
+}

android/app/src/androidTest/java/io/narl/protonstream/live/LiveShareTest.kt

@@ -0,0 +1,274 @@
+package io.narl.protonstream.live
+
+import android.graphics.SurfaceTexture
+import android.view.Surface
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import androidx.test.platform.app.InstrumentationRegistry
+import io.narl.protonstream.playback.NativeMpvHost
+import java.io.File
+import java.util.concurrent.ConcurrentHashMap
+import java.util.concurrent.atomic.AtomicBoolean
+import java.util.concurrent.atomic.AtomicLong
+import kotlinx.coroutines.runBlocking
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNotNull
+import org.junit.Assert.assertTrue
+import org.junit.Assume.assumeTrue
+import org.junit.BeforeClass
+import org.junit.Test
+import org.junit.runner.RunWith
+import uniffi.pstr_android.AndroidEngine
+import uniffi.pstr_android.AndroidPaths
+import uniffi.pstr_android.AndroidSecretStore
+import uniffi.pstr_android.DownloadObserver
+import uniffi.pstr_android.EpisodeRecord
+
+/**
+ * The cases `docs/ANDROID.md` requires that cannot be answered without a real
+ * share: that a link resolves into a playable catalog, that libmpv actually
+ * decodes the decrypted stream, that a cancelled download leaves a resumable
+ * `.part`, and that a resume position survives a restart.
+ *
+ * The link is an instrumentation argument rather than a constant or a file, so
+ * the secret never enters the repository:
+ *
+ * ```
+ * -Pandroid.testInstrumentationRunnerArguments.pstr.shareUrl=...
+ * ```
+ *
+ * Without it every test here is skipped by assumption, and
+ * `scripts/android-acceptance.sh` reports the matrix as incomplete.
+ *
+ * Read-only against the share by construction: nothing here uploads, renames or
+ * deletes anything remote. It writes only to this test's own temporary
+ * directories.
+ */
+@RunWith(AndroidJUnit4::class)
+class LiveShareTest {
+    @Test
+    fun theShareResolvesIntoAPlayableCatalog() {
+        val episodes = episodes()
+        assertTrue("the crawl found no playable file in the share", episodes.isNotEmpty())
+        // A file with no size cannot be streamed: the block layer needs the
+        // length to place block boundaries at all.
+        val sized = episodes.filter { (it.size ?: 0uL) > 0uL }
+        assertTrue("no episode in the share reported a size", sized.isNotEmpty())
+    }
+
+    @Test
+    fun openingAnEpisodeYieldsASeekableRevision() {
+        val episode = playable()
+        val stream = runBlocking {
+            engine.openStream(episode.shareId, episode.volumeId, episode.linkId)
+        }
+        try {
+            assertTrue("the opened revision has no length", stream.size() > 0uL)
+            // Without a revision id the block cache cannot tell one revision of
+            // a file from another, and a stale block would be served as fresh.
+            assertTrue("the opened revision has no id", stream.revisionId().isNotBlank())
+        } finally {
+            runBlocking { engine.releaseStream(episode.shareId, episode.volumeId, episode.linkId) }
+        }
+    }
+
+    /**
+     * The whole pipeline in one assertion: Proton block storage, decryption,
+     * the Rust stream C ABI, the JNI adapter and libmpv's demuxer. If the
+     * position advances, real decrypted bytes reached the decoder.
+     */
+    @Test
+    fun libmpvDecodesTheDecryptedStream() {
+        val episode = playable()
+        val texture = SurfaceTexture(0).apply { setDefaultBufferSize(1280, 720) }
+        val surface = Surface(texture)
+        val host = NativeMpvHost()
+        val key = "${episode.shareId}:${episode.linkId}"
+        try {
+            host.attachSurface(surface)
+            val stream = runBlocking {
+                engine.openStream(episode.shareId, episode.volumeId, episode.linkId)
+            }
+            runBlocking { host.play(key, stream.nativeHandle(), stream.size()) }
+            host.setMuted(true)
+            host.setPaused(false)
+
+            val playing = waitFor(PLAYBACK_TIMEOUT_MS) { host.state.value.position > 0.0 }
+            assertTrue(
+                "libmpv never advanced past zero: ${host.state.value}",
+                playing,
+            )
+            // One host serves every episode in turn, so a reading that does not
+            // name this one would resume the wrong file.
+            assertEquals(key, host.state.value.media)
+            assertTrue("libmpv reported no duration", host.state.value.duration > 0.0)
+        } finally {
+            host.stop()
+            host.detachSurface()
+            host.close()
+            surface.release()
+            texture.release()
+            runBlocking { engine.releaseStream(episode.shareId, episode.volumeId, episode.linkId) }
+        }
+    }
+
+    /**
+     * Cancellation is polled between whole Proton blocks precisely so the bytes
+     * already written stay usable. This checks the retained `.part` is counted
+     * as partial rather than as a finished file, and that resuming continues
+     * from it instead of starting over.
+     */
+    @Test
+    fun aCancelledDownloadLeavesAResumablePartFile() {
+        val episode = playable()
+        val firstRun = CancelAfter(bytes = RESUME_THRESHOLD_BYTES)
+        runCatching {
+            runBlocking {
+                engine.downloadEpisode(episode.shareId, episode.volumeId, episode.linkId, firstRun)
+            }
+        }
+        assumeTrue(
+            "the episode finished before cancellation could be observed; it is too small for this case",
+            !firstRun.completed,
+        )
+        assertTrue("the download reported no progress at all", firstRun.observed > 0L)
+
+        val retained = engine.storageUsage()
+        assertTrue("a cancelled download retained no bytes", retained.partialBytes > 0uL)
+        assertEquals("a cancelled download counted as a finished file", 0uL, retained.offlineCount)
+
+        // Resuming must pick up where the .part ended rather than at zero.
+        val secondRun = CancelAfter(bytes = retained.partialBytes.toLong() + RESUME_THRESHOLD_BYTES)
+        runCatching {
+            runBlocking {
+                engine.downloadEpisode(episode.shareId, episode.volumeId, episode.linkId, secondRun)
+            }
+        }
+        assertTrue(
+            "resuming restarted from zero: first reading was ${secondRun.firstReading}, " +
+                "but ${retained.partialBytes} bytes were already retained",
+            secondRun.firstReading >= retained.partialBytes.toLong(),
+        )
+
+        runBlocking { engine.removeOfflineEpisode(episode.shareId, episode.linkId) }
+        assertEquals(
+            "removing the episode left partial bytes behind",
+            0uL,
+            engine.storageUsage().partialBytes,
+        )
+    }
+
+    /** What the viewer sees as "continue watching" after the app is killed. */
+    @Test
+    fun aResumePositionSurvivesReopeningTheCatalog() {
+        val episode = playable()
+        engine.saveWatchState(episode.shareId, episode.linkId, RESUME_POSITION, null, false)
+
+        val reopened = AndroidEngine(paths, secrets)
+        val state = reopened.watchState(episode.shareId, episode.linkId)
+        assertNotNull("the resume position did not survive a reopen", state)
+        assertEquals(RESUME_POSITION, state!!.positionSecs, 0.001)
+        assertEquals(false, state.watched)
+
+        // The catalog view is what the UI reads, so it has to agree.
+        val listed = reopened.library(null)
+            .flatMap { it.seasons }
+            .flatMap { it.episodes }
+            .first { it.linkId == episode.linkId }
+        assertEquals(RESUME_POSITION, listed.resumeAt ?: -1.0, 0.001)
+    }
+
+    /** Cancels once the download has written enough to prove a resume. */
+    private class CancelAfter(private val bytes: Long) : DownloadObserver {
+        private val cancelled = AtomicBoolean(false)
+        private val progress = AtomicLong(0)
+        private val first = AtomicLong(-1)
+
+        val observed: Long get() = progress.get()
+        val firstReading: Long get() = first.get()
+        val completed: Boolean get() = !cancelled.get()
+
+        override fun onProgress(downloaded: ULong, total: ULong) {
+            first.compareAndSet(-1, downloaded.toLong())
+            progress.set(downloaded.toLong())
+            if (downloaded.toLong() >= bytes) cancelled.set(true)
+        }
+
+        override fun isCancelled(): Boolean = cancelled.get()
+    }
+
+    private fun episodes(): List<EpisodeRecord> =
+        engine.library(null).flatMap { it.seasons }.flatMap { it.episodes }
+
+    private fun playable(): EpisodeRecord =
+        episodes().firstOrNull { (it.size ?: 0uL) > 0uL }
+            ?: throw AssertionError("the share has no sized file to play")
+
+    private fun waitFor(timeoutMs: Long, condition: () -> Boolean): Boolean {
+        val deadline = System.currentTimeMillis() + timeoutMs
+        while (System.currentTimeMillis() < deadline) {
+            if (condition()) return true
+            Thread.sleep(200)
+        }
+        return false
+    }
+
+    /** Stands in for Keystore, so a bridge failure cannot be blamed on crypto. */
+    private class MemorySecretStore : AndroidSecretStore {
+        private val entries = ConcurrentHashMap<String, String>()
+
+        override fun set(key: String, value: String) {
+            entries[key] = value
+        }
+
+        override fun get(key: String): String? = entries[key]
+
+        override fun delete(key: String) {
+            entries.remove(key)
+        }
+    }
+
+    companion object {
+        private const val SHARE_URL_ARGUMENT = "pstr.shareUrl"
+        private const val SHARE_PASSWORD_ARGUMENT = "pstr.sharePassword"
+
+        /** Long enough for a cold connection, a crawl and a first block read. */
+        private const val PLAYBACK_TIMEOUT_MS = 60_000L
+
+        /** Enough written bytes to prove a resume, small enough to stay quick. */
+        private const val RESUME_THRESHOLD_BYTES = 4L * 1024 * 1024
+
+        private const val RESUME_POSITION = 137.5
+
+        private lateinit var paths: AndroidPaths
+        private lateinit var secrets: AndroidSecretStore
+        private lateinit var engine: AndroidEngine
+
+        @BeforeClass
+        @JvmStatic
+        fun openTheShare() {
+            System.loadLibrary("pstr_android")
+            val arguments = InstrumentationRegistry.getArguments()
+            val url = arguments.getString(SHARE_URL_ARGUMENT)
+            assumeTrue(
+                "set -Pandroid.testInstrumentationRunnerArguments.$SHARE_URL_ARGUMENT to run the live cases",
+                !url.isNullOrBlank(),
+            )
+            val password = arguments.getString(SHARE_PASSWORD_ARGUMENT)?.takeIf { it.isNotBlank() }
+
+            val root = File.createTempFile("pstr-live", "").let {
+                it.delete()
+                it.mkdirs()
+                it
+            }
+            paths = AndroidPaths(
+                File(root, "config").absolutePath,
+                File(root, "data").absolutePath,
+                File(root, "cache").absolutePath,
+            )
+            secrets = MemorySecretStore()
+            engine = AndroidEngine(paths, secrets)
+            engine.addShare("acceptance", url!!, password)
+            runBlocking { engine.crawl(null) }
+        }
+    }
+}

android/app/src/androidTest/java/io/narl/protonstream/native/KeystoreSecretStoreTest.kt

@@ -0,0 +1,155 @@
+package io.narl.protonstream.native
+
+import android.content.Context
+import android.util.Base64
+import androidx.test.core.app.ApplicationProvider
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import java.security.KeyStore
+import org.junit.After
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertThrows
+import org.junit.Assert.assertNotEquals
+import org.junit.Assert.assertNull
+import org.junit.Assert.assertTrue
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import uniffi.pstr_android.BridgeException
+
+/**
+ * Runs on a device because Android Keystore has no host implementation — which
+ * is why nothing pinned this before. The share fragment and any custom link
+ * password are the only user secrets the app holds, and losing the key makes
+ * every share unopenable, so the failure modes matter as much as the happy path.
+ */
+@RunWith(AndroidJUnit4::class)
+class KeystoreSecretStoreTest {
+    private lateinit var context: Context
+    private lateinit var store: KeystoreSecretStore
+
+    @Before
+    fun setUp() {
+        context = ApplicationProvider.getApplicationContext()
+        clearPreferences()
+        store = KeystoreSecretStore(context)
+    }
+
+    @After
+    fun tearDown() {
+        clearPreferences()
+    }
+
+    @Test
+    fun aSecretSurvivesARoundTrip() {
+        store.set("share-1", "correct horse battery staple")
+        assertEquals("correct horse battery staple", store.get("share-1"))
+    }
+
+    @Test
+    fun anAbsentSecretIsNullRatherThanEmpty() {
+        assertNull(store.get("never-written"))
+    }
+
+    @Test
+    fun deleteRemovesTheSecret() {
+        store.set("share-1", "value")
+        store.delete("share-1")
+        assertNull(store.get("share-1"))
+    }
+
+    @Test
+    fun aUnicodeSecretIsNotMangled() {
+        val value = "パスワード・🎬・ü"
+        store.set("share-1", value)
+        assertEquals(value, store.get("share-1"))
+    }
+
+    /**
+     * GCM is catastrophic under IV reuse: two secrets encrypted with the same
+     * key and IV leak the XOR of their plaintexts. `Cipher.init(ENCRYPT_MODE)`
+     * is what generates a fresh one, so this pins that the code never pins it.
+     */
+    @Test
+    fun everyWriteUsesAFreshInitialisationVector() {
+        store.set("share-1", "same plaintext")
+        val first = rawPayload("share-1")
+        store.set("share-1", "same plaintext")
+        val second = rawPayload("share-1")
+
+        val firstIv = first.copyOfRange(0, IV_SIZE)
+        val secondIv = second.copyOfRange(0, IV_SIZE)
+        assertNotEquals(Base64.encodeToString(firstIv, Base64.NO_WRAP), Base64.encodeToString(secondIv, Base64.NO_WRAP))
+    }
+
+    @Test
+    fun theStoredFormIsNotThePlaintext() {
+        store.set("share-1", "correct horse battery staple")
+        val stored = context.getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE)
+            .getString("share-1", null)
+        assertTrue(stored != null && !stored.contains("correct horse"))
+    }
+
+    /**
+     * A tampered payload must not decrypt, and must fail as a [BridgeException].
+     * An `AEADBadTagException` crossing the FFI has no mapping on the Rust side,
+     * and an unmapped callback exception panics the calling thread (B18).
+     */
+    @Test
+    fun aTamperedPayloadFailsToDecrypt() {
+        store.set("share-1", "value")
+        val payload = rawPayload("share-1")
+        payload[payload.size - 1] = (payload[payload.size - 1].toInt() xor 0x01).toByte()
+        writeRawPayload("share-1", payload)
+
+        assertThrows(BridgeException::class.java) { store.get("share-1") }
+    }
+
+    @Test
+    fun aTruncatedPayloadIsRejectedBeforeDecryption() {
+        store.set("share-1", "value")
+        writeRawPayload("share-1", rawPayload("share-1").copyOfRange(0, IV_SIZE))
+
+        assertThrows(BridgeException::class.java) { store.get("share-1") }
+    }
+
+    /**
+     * The device-side half of B18: this is what a lockscreen change or a device
+     * restore does to the key. It must fail the read rather than the process,
+     * and the store must still accept a re-entered secret afterwards — which is
+     * what the shares screen's "Re-enter link" depends on.
+     */
+    @Test
+    fun aLostKeyFailsTheReadRatherThanTheProcess() {
+        store.set("share-1", "value")
+        KeyStore.getInstance("AndroidKeyStore").apply { load(null) }.deleteEntry(KEY_ALIAS)
+
+        assertThrows(BridgeException::class.java) { store.get("share-1") }
+
+        // The store must still be usable for a re-entered secret.
+        store.set("share-1", "re-entered")
+        assertEquals("re-entered", store.get("share-1"))
+    }
+
+    private fun rawPayload(key: String): ByteArray {
+        val encoded = context.getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE)
+            .getString(key, null) ?: error("no payload for $key")
+        return Base64.decode(encoded, Base64.NO_WRAP)
+    }
+
+    private fun writeRawPayload(key: String, payload: ByteArray) {
+        context.getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE)
+            .edit()
+            .putString(key, Base64.encodeToString(payload, Base64.NO_WRAP))
+            .commit()
+    }
+
+    private fun clearPreferences() {
+        context.getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE).edit().clear().commit()
+    }
+
+    private companion object {
+        const val PREFERENCES = "proton_stream_secrets"
+        const val KEY_ALIAS = "proton-stream-share-secrets-v1"
+        const val IV_SIZE = 12
+    }
+}

android/app/src/androidTest/java/io/narl/protonstream/native/UniFfiBoundaryTest.kt

@@ -0,0 +1,117 @@
+package io.narl.protonstream.native
+
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import java.io.File
+import java.util.concurrent.ConcurrentHashMap
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNotNull
+import org.junit.Assert.assertNull
+import org.junit.Assert.assertTrue
+import org.junit.BeforeClass
+import org.junit.Test
+import org.junit.runner.RunWith
+import uniffi.pstr_android.AndroidEngine
+import uniffi.pstr_android.AndroidPaths
+import uniffi.pstr_android.AndroidSecretStore
+import uniffi.pstr_android.chapterPlan
+import uniffi.pstr_android.skipOffer
+
+/**
+ * The first thing that crosses the UniFFI boundary on a real device. It is
+ * deliberately offline: it proves the ABI, the generated bindings, the callback
+ * interface and the SQLite open all work, without needing a share.
+ *
+ * If this fails and the Rust workspace tests pass, the fault is in packaging —
+ * a missing ABI in `jniLibs`, a stale binding, or an R8 rule (run it with
+ * `ANDROID_TEST_BUILD_TYPE=release` to check the shipped configuration).
+ */
+@RunWith(AndroidJUnit4::class)
+class UniFfiBoundaryTest {
+    /** Stands in for Keystore so a bridge failure cannot be blamed on crypto. */
+    private class MemorySecretStore : AndroidSecretStore {
+        val entries = ConcurrentHashMap<String, String>()
+        var reads = 0
+            private set
+
+        override fun set(key: String, value: String) {
+            entries[key] = value
+        }
+
+        override fun get(key: String): String? {
+            reads += 1
+            return entries[key]
+        }
+
+        override fun delete(key: String) {
+            entries.remove(key)
+        }
+    }
+
+    private fun engine(secrets: AndroidSecretStore = MemorySecretStore()): AndroidEngine {
+        val root = File.createTempFile("pstr-bridge", "").let {
+            it.delete()
+            it.mkdirs()
+            it
+        }
+        return AndroidEngine(
+            AndroidPaths(
+                File(root, "config").absolutePath,
+                File(root, "data").absolutePath,
+                File(root, "cache").absolutePath,
+            ),
+            secrets,
+        )
+    }
+
+    @Test
+    fun theEngineOpensAgainstEmptyDirectories() {
+        val engine = engine()
+        assertTrue(engine.shares().isEmpty())
+        assertTrue(engine.library(null).isEmpty())
+    }
+
+    @Test
+    fun storageUsageReportsZeroOnAFreshInstall() {
+        val usage = engine().storageUsage()
+        assertNotNull(usage)
+        assertEquals(0UL, usage.offlineBytes)
+        assertEquals(0UL, usage.partialBytes)
+        assertEquals(0UL, usage.offlineCount)
+    }
+
+    @Test
+    fun metadataSettingsAreReadableAndDefaultToDisabled() {
+        // Enrichment is opt-in; a default of enabled would send titles to a
+        // third party before the viewer has agreed to it.
+        assertEquals(false, engine().metadataSettings().enabled)
+    }
+
+    @Test
+    fun aSecondEngineReopensTheSameCatalog() {
+        val secrets = MemorySecretStore()
+        engine(secrets).shares()
+        // Reopening is the process-restart path; a schema or lock fault shows up
+        // here rather than on a user's device.
+        assertTrue(engine(secrets).shares().isEmpty())
+    }
+
+    /**
+     * Chapter classification is shared Rust that desktop already pins
+     * (`docs/BUGS.md` B12). This runs the same code through the bindings, so a
+     * lowering fault in the record types cannot pass unnoticed.
+     */
+    @Test
+    fun chapterPlanningCrossesTheBoundaryIntact() {
+        val plan = chapterPlan(emptyList(), 1560.0)
+        assertNotNull(plan)
+        assertNull(skipOffer(plan, 12.0))
+    }
+
+    companion object {
+        @BeforeClass
+        @JvmStatic
+        fun loadLibrary() {
+            System.loadLibrary("pstr_android")
+        }
+    }
+}

android/app/src/main/AndroidManifest.xml

@@ -7,11 +7,21 @@
     <uses-permission android:name="android.permission.FOREGROUND_SERVICE_DATA_SYNC" />
     <uses-permission android:name="android.permission.FOREGROUND_SERVICE_MEDIA_PLAYBACK" />
 
+    <!--
+      Android TV: listed in its launcher, and installable without a touch
+      screen. Neither is required, so phones are offered the same build.
+    -->
+    <uses-feature android:name="android.software.leanback" android:required="false" />
+    <uses-feature android:name="android.hardware.touchscreen" android:required="false" />
+
     <application
         android:name=".ProtonStreamApplication"
         android:allowBackup="false"
         android:dataExtractionRules="@xml/data_extraction_rules"
-        android:icon="@drawable/ic_launcher_foreground"
+        android:enableOnBackInvokedCallback="true"
+        tools:targetApi="33"
+        android:icon="@mipmap/ic_launcher"
+        android:banner="@drawable/tv_banner"
         android:label="@string/app_name"
         android:supportsRtl="true"
         android:theme="@style/Theme.ProtonStream">
@@ -29,14 +39,33 @@
 
         <activity
             android:name=".MainActivity"
-            android:configChanges="screenSize|smallestScreenSize|screenLayout|orientation"
+            android:label="@string/launcher_name"
+            android:configChanges="screenSize|smallestScreenSize|screenLayout|orientation|uiMode|density|fontScale|locale|layoutDirection|keyboardHidden"
             android:exported="true"
             android:launchMode="singleTask"
-            android:supportsPictureInPicture="true"
             android:resizeableActivity="true">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
                 <category android:name="android.intent.category.LAUNCHER" />
+                <category android:name="android.intent.category.LEANBACK_LAUNCHER" />
+            </intent-filter>
+            <!--
+              Proton Drive public links. autoVerify="false", said explicitly:
+              the domain is Proton's, so this can never be a verified App Link.
+              Android only opens these here once "Open supported links" is
+              allowed in the app's settings; sharing a link to the app works
+              without that.
+            -->
+            <intent-filter android:autoVerify="false">
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+                <data android:scheme="https" android:host="drive.proton.me" android:pathPrefix="/urls/" />
+            </intent-filter>
+            <intent-filter>
+                <action android:name="android.intent.action.SEND" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <data android:mimeType="text/plain" />
             </intent-filter>
         </activity>
 

android/app/src/main/assets/licenses/Inter-OFL.txt

@@ -0,0 +1,92 @@
+Copyright (c) 2016 The Inter Project Authors (https://github.com/rsms/inter)
+
+This Font Software is licensed under the SIL Open Font License, Version 1.1.
+This license is copied below, and is also available with a FAQ at:
+http://scripts.sil.org/OFL
+
+-----------------------------------------------------------
+SIL OPEN FONT LICENSE Version 1.1 - 26 February 2007
+-----------------------------------------------------------
+
+PREAMBLE
+The goals of the Open Font License (OFL) are to stimulate worldwide
+development of collaborative font projects, to support the font creation
+efforts of academic and linguistic communities, and to provide a free and
+open framework in which fonts may be shared and improved in partnership
+with others.
+
+The OFL allows the licensed fonts to be used, studied, modified and
+redistributed freely as long as they are not sold by themselves. The
+fonts, including any derivative works, can be bundled, embedded,
+redistributed and/or sold with any software provided that any reserved
+names are not used by derivative works. The fonts and derivatives,
+however, cannot be released under any other type of license. The
+requirement for fonts to remain under this license does not apply
+to any document created using the fonts or their derivatives.
+
+DEFINITIONS
+"Font Software" refers to the set of files released by the Copyright
+Holder(s) under this license and clearly marked as such. This may
+include source files, build scripts and documentation.
+
+"Reserved Font Name" refers to any names specified as such after the
+copyright statement(s).
+
+"Original Version" refers to the collection of Font Software components as
+distributed by the Copyright Holder(s).
+
+"Modified Version" refers to any derivative made by adding to, deleting,
+or substituting -- in part or in whole -- any of the components of the
+Original Version, by changing formats or by porting the Font Software to a
+new environment.
+
+"Author" refers to any designer, engineer, programmer, technical
+writer or other person who contributed to the Font Software.
+
+PERMISSION AND CONDITIONS
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of the Font Software, to use, study, copy, merge, embed, modify,
+redistribute, and sell modified and unmodified copies of the Font
+Software, subject to the following conditions:
+
+1) Neither the Font Software nor any of its individual components,
+in Original or Modified Versions, may be sold by itself.
+
+2) Original or Modified Versions of the Font Software may be bundled,
+redistributed and/or sold with any software, provided that each copy
+contains the above copyright notice and this license. These can be
+included either as stand-alone text files, human-readable headers or
+in the appropriate machine-readable metadata fields within text or
+binary files as long as those fields can be easily viewed by the user.
+
+3) No Modified Version of the Font Software may use the Reserved Font
+Name(s) unless explicit written permission is granted by the corresponding
+Copyright Holder. This restriction only applies to the primary font name as
+presented to the users.
+
+4) The name(s) of the Copyright Holder(s) or the Author(s) of the Font
+Software shall not be used to promote, endorse or advertise any
+Modified Version, except to acknowledge the contribution(s) of the
+Copyright Holder(s) and the Author(s) or with their explicit written
+permission.
+
+5) The Font Software, modified or unmodified, in part or in whole,
+must be distributed entirely under this license, and must not be
+distributed under any other license. The requirement for fonts to
+remain under this license does not apply to any document created
+using the Font Software.
+
+TERMINATION
+This license becomes null and void if any of the above conditions are
+not met.
+
+DISCLAIMER
+THE FONT SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
+OF COPYRIGHT, PATENT, TRADEMARK, OR OTHER RIGHT. IN NO EVENT SHALL THE
+COPYRIGHT HOLDER BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+INCLUDING ANY GENERAL, SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL
+DAMAGES, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF THE USE OR INABILITY TO USE THE FONT SOFTWARE OR FROM
+OTHER DEALINGS IN THE FONT SOFTWARE.

android/app/src/main/assets/licenses/THIRD_PARTY_NOTICES.md

@@ -6,11 +6,12 @@ complete GNU GPL version 3 text is packaged beside this file as `GPL-3.0.txt`.
 | Component | License |
 |---|---|
 | mpv/libmpv | GPL-2.0-or-later by default; verify the pinned build configuration |
-| LLVM libc++ shared runtime (Android NDK r29) | Apache-2.0 WITH LLVM-exception |
+| LLVM libc++ shared runtime (Android NDK r30) | Apache-2.0 WITH LLVM-exception |
 | AndroidX and Jetpack Compose | Apache-2.0 |
 | Kotlin | Apache-2.0 |
 | JNA | Apache-2.0 or LGPL-2.1-or-later |
 | UniFFI | MPL-2.0 |
+| Inter typeface (bundled, `Inter-OFL.txt`) | OFL-1.1 |
 | proton-stream reusable Rust crates | MIT |
 
 Before release, replace this dependency summary with an inventory generated

android/app/src/main/cpp/CMakeLists.txt

@@ -12,6 +12,12 @@ add_library(pstr_mpv SHARED pstr_mpv.cpp)
 add_library(mpv SHARED IMPORTED)
 set_target_properties(mpv PROPERTIES
     IMPORTED_LOCATION "${PSTR_MPV_ROOT}/jniLibs/${ANDROID_ABI}/libmpv.so")
+# libmpv links FFmpeg dynamically and does not re-export it, so registering the
+# JavaVM that MediaCodec needs means linking libavcodec ourselves. It is already
+# packaged in the same ABI directory as part of libmpv's dependency closure.
+add_library(avcodec SHARED IMPORTED)
+set_target_properties(avcodec PROPERTIES
+    IMPORTED_LOCATION "${PSTR_MPV_ROOT}/jniLibs/${ANDROID_ABI}/libavcodec.so")
 
 target_compile_features(pstr_mpv PRIVATE cxx_std_20)
 target_compile_options(pstr_mpv PRIVATE -Wall -Wextra -Werror)
@@ -20,4 +26,4 @@ target_include_directories(pstr_mpv PRIVATE "${PSTR_MPV_ROOT}/include")
 # packaged into the same ABI directory in the APK.
 target_link_directories(pstr_mpv PRIVATE "${PSTR_RUST_JNI_ROOT}/${ANDROID_ABI}")
 target_link_options(pstr_mpv PRIVATE "-Wl,-l:libpstr_android.so")
-target_link_libraries(pstr_mpv PRIVATE mpv android EGL log)
+target_link_libraries(pstr_mpv PRIVATE mpv avcodec android EGL log)

android/app/src/main/cpp/pstr_mpv.cpp

@@ -1,6 +1,7 @@
 #include "pstr_mpv.h"
 
 #include <EGL/egl.h>
+#include <android/log.h>
 #include <android/native_window.h>
 #include <android/native_window_jni.h>
 #include <jni.h>
@@ -8,6 +9,10 @@
 #include <mpv/render_gl.h>
 #include <mpv/stream_cb.h>
 
+extern "C" {
+#include <libavcodec/jni.h>
+}
+
 #include <atomic>
 #include <algorithm>
 #include <charconv>
@@ -22,10 +27,13 @@
 #include <string_view>
 #include <thread>
 #include <utility>
+#include <vector>
 
 namespace {
 
 constexpr const char *kProtocol = "pstr";
+/// mpv's `hwdec` when hardware decoding is on. Why this value: `Player()`.
+constexpr const char *kHardwareDecoding = "auto-copy-safe";
 
 struct StreamCookie {
     uint64_t handle;
@@ -86,16 +94,32 @@ int64_t stream_size(void *opaque) noexcept {
     });
 }
 
+/// mpv wants its request slot back — a seek, or a teardown.
+///
+/// The flag alone only stops the *next* read; the one already parked in a 4 MiB
+/// block fetch has to be interrupted in Rust, or `mpv_terminate_destroy` waits
+/// out the whole fetch while joining the demuxer thread.
 void stream_cancel(void *opaque) noexcept {
     c_boundary([=] {
         if (auto *stream = static_cast<StreamCookie *>(opaque)) {
             stream->cancelled.store(true, std::memory_order_relaxed);
+            pstr_android_stream_cancel(stream->handle);
         }
     });
 }
 
+/// Releases the Rust stream behind the file mpv has finished with.
+///
+/// Ownership sits here rather than in Kotlin because this is the one moment
+/// that is *defined* to be after mpv's last read: `loadfile` is asynchronous, so
+/// a Kotlin-side release issued when the next load returns can land while the
+/// outgoing demuxer is still reading — and, if the release names the handle the
+/// registry has already swapped, takes the incoming episode's stream with it.
 void stream_close(void *opaque) noexcept {
-    c_boundary([=] { delete static_cast<StreamCookie *>(opaque); });
+    c_boundary([=] {
+        std::unique_ptr<StreamCookie> cookie(static_cast<StreamCookie *>(opaque));
+        if (cookie) pstr_android_stream_release(cookie->handle);
+    });
 }
 
 int stream_open(void *, char *uri, mpv_stream_cb_info *info) noexcept {
@@ -130,6 +154,29 @@ void *resolve_gl(void *, const char *name) noexcept {
     });
 }
 
+/// Why the open file ended, mirroring `pstr_player::EndReason` so that the two
+/// clients agree on what "finished" means. Only [Eof] is an episode the viewer
+/// watched to the end; the rest are a stop, a shutdown or a failure, and none of
+/// them may mark anything watched or advance to the next episode.
+enum class EndReason : int {
+    None = 0,
+    Eof = 1,
+    Stopped = 2,
+    Quit = 3,
+    Failed = 4,
+    Other = 5,
+};
+
+EndReason end_reason_of(int reason) {
+    switch (reason) {
+        case MPV_END_FILE_REASON_EOF: return EndReason::Eof;
+        case MPV_END_FILE_REASON_STOP: return EndReason::Stopped;
+        case MPV_END_FILE_REASON_QUIT: return EndReason::Quit;
+        case MPV_END_FILE_REASON_ERROR: return EndReason::Failed;
+        default: return EndReason::Other;
+    }
+}
+
 struct PlaybackState {
     double position = 0.0;
     double duration = 0.0;
@@ -137,6 +184,44 @@ struct PlaybackState {
     bool paused = true;
     bool muted = false;
     bool ended = false;
+    EndReason end_reason = EndReason::None;
+    /// mpv has run out of buffered data and stopped to refill. Distinct from
+    /// [paused], which is the viewer's doing: a frozen picture that nothing
+    /// explains is indistinguishable from a hung app.
+    bool buffering = false;
+    /// How full the demuxer cache is while [buffering], 0–100.
+    double cache_percent = 0.0;
+    /// Between a seek being issued and playback actually resuming. The seek bar
+    /// has moved but the picture has not.
+    bool seeking = false;
+    /// How far into the file the demuxer has read ahead, in seconds; what the
+    /// seek bar shades, so a jump into it is known to cost no fetch.
+    double cached_until = 0.0;
+    /// True between `loadfile` being issued and mpv acknowledging it with
+    /// `START_FILE`. Everything mpv reports in that window still describes the
+    /// *outgoing* file — including the `END_FILE(STOP)` that stopping it emits —
+    /// and must not be attributed to the file being loaded.
+    bool loading = false;
+    /// The picture's display size, once mpv has decoded enough to know it.
+    /// Zero until then.
+    double video_width = 0.0;
+    double video_height = 0.0;
+    /// Which loaded file this state describes. Bumped by every load, so a
+    /// reader can tell "episode two, second zero" from a leftover reading of
+    /// episode one — which is the difference between resuming an episode where
+    /// the viewer left it and resuming it where the *previous* one ended.
+    int64_t generation = 0;
+    /// mpv has loaded this generation's file and made its own track pick,
+    /// which is the first moment the pick can be second-guessed.
+    bool loaded = false;
+};
+
+/// A subtitle file published for mpv, and what to call it.
+struct Subtitle {
+    uint64_t handle = 0;
+    std::string title;
+    std::string language;
+    bool select = false;
 };
 
 class Player {
@@ -148,7 +233,16 @@ class Player {
         option("vo", "libmpv");
         option("force-window", "no");
         option("video-timing-offset", "0");
-        option("hwdec", "auto-safe");
+        // The default; `load` sets it per file from the viewer's setting.
+        // `-copy-safe`, not `-safe`. The direct MediaCodec decoders render into
+        // an `ANativeWindow` the decoder is handed at init, and this player has
+        // none to give: the picture goes through `vo_libmpv` and an EGL pbuffer,
+        // and the SurfaceView — when there is one at all — attaches later than
+        // the load. `auto-safe` picks them anyway and every file opens with
+        // `hevc_mediacodec: Both surface and native_window are NULL` before
+        // falling back. The copy variants decode in hardware and hand back
+        // ordinary frames, which is what this render path can actually use.
+        option("hwdec", kHardwareDecoding);
         option("cache", "yes");
         option("cache-secs", "30");
         option("demuxer-readahead-secs", "30");
@@ -165,6 +259,14 @@ class Player {
         observe("pause", 3, MPV_FORMAT_FLAG);
         observe("volume", 4, MPV_FORMAT_DOUBLE);
         observe("mute", 5, MPV_FORMAT_FLAG);
+        observe("video-params/dw", 6, MPV_FORMAT_INT64);
+        observe("video-params/dh", 7, MPV_FORMAT_INT64);
+        observe("paused-for-cache", 8, MPV_FORMAT_FLAG);
+        observe("cache-buffering-state", 9, MPV_FORMAT_INT64);
+        observe("demuxer-cache-time", 10, MPV_FORMAT_DOUBLE);
+        // Errors mpv reports about the file itself, rather than about the
+        // request that opened it. Without these a failed demux is silent.
+        mpv_request_log_messages(mpv_, "error");
         events_ = std::thread([this] { event_loop(); });
         renderer_ = std::thread([this] { render_loop(); });
     }
@@ -211,25 +313,69 @@ class Player {
     }
 
     bool load(uint64_t handle, double start, const std::string &audio,
-              const std::string &subtitle, bool subtitles) {
+              const std::string &subtitle, bool subtitles,
+              bool hardware_decoding) {
         if (!mpv_) return false;
-        {
+        // Per file, before `loadfile`: a device whose decoder shows green
-            std::unique_lock lock(render_mutex_);
+        // frames is fixed from the next episode without restarting the core.
-            if (!render_cv_.wait_for(lock, std::chrono::seconds(5), [this] { return render_ != nullptr || !running_.load(); })) return false;
+        set_string("hwdec", hardware_decoding ? kHardwareDecoding : "no");
-        }
+        // No wait for a render context. It is created with the render thread and
+        // needs no window, and a load that cannot get one plays audio anyway —
+        // waiting for a surface here is what made background playback fail after
+        // a five-second stall.
         if (!audio.empty()) set_string("alang", audio);
         if (!subtitle.empty()) set_string("slang", subtitle);
         set_string("sid", subtitles ? "auto" : "no");
         pending_start_.store(std::max(0.0, start));
+        // Retire the outgoing file's position, duration and end flag *before*
+        // the new one loads. mpv only republishes them once it has demuxed
+        // enough of the stream, and until then every reader would otherwise see
+        // the last episode's clock under the new episode's name.
+        {
+            std::lock_guard lock(state_mutex_);
+            const double volume = state_.volume;
+            const bool muted = state_.muted;
+            // `pause` is a property of the core, not of the file: mpv carries it
+            // across `loadfile` unchanged and therefore never re-publishes it.
+            // Resetting it to the struct's default would leave every reader
+            // believing a playing file is paused for as long as it is open, and
+            // every "play" they then send is a no-op against a core that never
+            // paused — which is a play/pause button that does nothing.
+            const bool paused = state_.paused;
+            const int64_t generation = state_.generation + 1;
+            state_ = PlaybackState{};
+            state_.volume = volume;
+            state_.muted = muted;
+            state_.paused = paused;
+            state_.generation = generation;
+            state_.loading = true;
+            error_.clear();
+            for (const auto &subtitle : pending_subtitles_) released_.push_back(subtitle.handle);
+            pending_subtitles_.clear();
+        }
+        flush_released();
         const std::string url = "pstr://" + std::to_string(handle);
         const char *command[] = {"loadfile", url.c_str(), nullptr};
-        if (mpv_command(mpv_, command) < 0) return false;
+        if (mpv_command(mpv_, command) < 0) {
+            // Nothing was issued, so no START_FILE will arrive to clear this.
+            std::lock_guard lock(state_mutex_);
+            state_.loading = false;
+            return false;
+        }
         return true;
     }
 
-    void pause(bool value) { set_flag("pause", value); }
+    /// Written through rather than left to the observer: the transport is drawn
+    /// from this state, and a tap that only shows its effect on mpv's next
+    /// property event reads as a button that missed.
+    void pause(bool value) {
+        set_flag("pause", value);
+        std::lock_guard lock(state_mutex_);
+        state_.paused = value;
+    }
     void seek(double seconds) { set_double("time-pos", std::max(0.0, seconds)); }
     void volume(double value) { set_double("volume", std::clamp(value, 0.0, 100.0)); }
+    void speed(double value) { set_double("speed", std::clamp(value, 0.25, 4.0)); }
     void mute(bool value) { set_flag("mute", value); }
     void select_track(bool audio, int64_t id) {
         const char *property = audio ? "aid" : "sid";
@@ -241,11 +387,38 @@ class Player {
         mpv_command(mpv_, command);
     }
 
+    /// A subtitle file beside the file of load `generation`, added once mpv
+    /// has that file loaded: an external track belongs to the file open at
+    /// the time. Handed over for a file already replaced, it is released
+    /// instead. `select` turns it on, but only when the file has no subtitle
+    /// of its own playing.
+    void add_subtitle(int64_t generation, Subtitle subtitle) {
+        bool now = false;
+        {
+            std::lock_guard lock(state_mutex_);
+            if (generation != state_.generation) {
+                released_.push_back(subtitle.handle);
+            } else if (loaded_generation_ == generation) {
+                now = true;
+            } else {
+                pending_subtitles_.push_back(std::move(subtitle));
+            }
+        }
+        flush_released();
+        if (now) attach_subtitle(subtitle);
+    }
+
     PlaybackState state() const {
         std::lock_guard lock(state_mutex_);
         return state_;
     }
 
+    /// The pending error, if any, consumed by reading it.
+    std::string take_error() {
+        std::lock_guard lock(state_mutex_);
+        return std::exchange(error_, std::string());
+    }
+
     std::string tracks_json() const {
         if (!mpv_) return "[]";
         int64_t count = 0;
@@ -258,6 +431,8 @@ class Player {
             char *lang_raw = nullptr;
             char *title_raw = nullptr;
             int selected = 0;
+            int is_default = 0;
+            int forced = 0;
             mpv_get_property(mpv_, (base + "id").c_str(), MPV_FORMAT_INT64, &id);
             mpv_get_property(mpv_, (base + "type").c_str(), MPV_FORMAT_STRING, &type_raw);
             MpvString type(type_raw);
@@ -266,30 +441,156 @@ class Player {
             mpv_get_property(mpv_, (base + "title").c_str(), MPV_FORMAT_STRING, &title_raw);
             MpvString title(title_raw);
             mpv_get_property(mpv_, (base + "selected").c_str(), MPV_FORMAT_FLAG, &selected);
+            mpv_get_property(mpv_, (base + "default").c_str(), MPV_FORMAT_FLAG, &is_default);
+            mpv_get_property(mpv_, (base + "forced").c_str(), MPV_FORMAT_FLAG, &forced);
             if (i) json += ',';
             json += "{\"id\":" + std::to_string(id) + ",\"type\":\"" + escape(type.get()) +
                     "\",\"language\":\"" + escape(lang.get()) + "\",\"title\":\"" +
-                    escape(title.get()) + "\",\"selected\":" + (selected ? "true" : "false") + "}";
+                    escape(title.get()) + "\",\"selected\":" + (selected ? "true" : "false") +
+                    ",\"default\":" + (is_default ? "true" : "false") +
+                    ",\"forced\":" + (forced ? "true" : "false") + "}";
+        }
+        return json + ']';
+    }
+
+    /// The file's chapters, read one sub-property at a time like the tracks.
+    /// What they *mean* is decided in Rust (`pstr_core::chapters`), so the
+    /// desktop and this client offer the same skips.
+    std::string chapters_json() const {
+        if (!mpv_) return "[]";
+        int64_t count = 0;
+        if (mpv_get_property(mpv_, "chapter-list/count", MPV_FORMAT_INT64, &count) < 0) return "[]";
+        std::string json = "[";
+        for (int64_t i = 0; i < count; ++i) {
+            const std::string base = "chapter-list/" + std::to_string(i) + "/";
+            char *title_raw = nullptr;
+            double start = 0.0;
+            mpv_get_property(mpv_, (base + "title").c_str(), MPV_FORMAT_STRING, &title_raw);
+            MpvString title(title_raw);
+            mpv_get_property(mpv_, (base + "time").c_str(), MPV_FORMAT_DOUBLE, &start);
+            if (i) json += ',';
+            json += "{\"index\":" + std::to_string(i) + ",\"title\":\"" + escape(title.get()) +
+                    "\",\"start\":" + std::to_string(start) + '}';
         }
         return json + ']';
     }
 
   private:
+    void attach_subtitle(const Subtitle &subtitle) {
+        bool showing = false;
+        if (char *sid = mpv_get_property_string(mpv_, "sid")) {
+            showing = std::strcmp(sid, "no") != 0;
+            mpv_free(sid);
+        }
+        const std::string url = "pstr://" + std::to_string(subtitle.handle);
+        std::vector<const char *> command{
+            "sub-add", url.c_str(), subtitle.select && !showing ? "select" : "auto",
+            subtitle.title.c_str()};
+        if (!subtitle.language.empty()) command.push_back(subtitle.language.c_str());
+        command.push_back(nullptr);
+        // On failure mpv may never have opened it, so nothing will close it.
+        // Releasing one it did open and close is a no-op.
+        if (mpv_command(mpv_, command.data()) < 0) pstr_android_stream_release(subtitle.handle);
+    }
+
+    /// Release the subtitle streams queued under `state_mutex_`, outside it:
+    /// a release runs Rust destructors, which must not run under a lock a
+    /// reader of the state may be waiting on.
+    void flush_released() {
+        std::vector<uint64_t> handles;
+        {
+            std::lock_guard lock(state_mutex_);
+            handles.swap(released_);
+        }
+        for (const uint64_t handle : handles) pstr_android_stream_release(handle);
+    }
+
     struct MpvFree {
         void operator()(char *value) const noexcept { if (value) mpv_free(value); }
     };
     using MpvString = std::unique_ptr<char, MpvFree>;
 
+    /// JSON-escape `text`, and re-encode it as Modified UTF-8.
+    ///
+    /// The result of this ends up in `NewStringUTF`, which does not take UTF-8:
+    /// it takes Modified UTF-8, where a character outside the basic plane is a
+    /// surrogate *pair* of three-byte sequences rather than one four-byte
+    /// sequence. Handing it real UTF-8 renders an emoji in a track title as
+    /// mojibake, and aborts the process under CheckJNI.
+    ///
+    /// Anything that is not well-formed UTF-8 is dropped rather than passed
+    /// through, for the same reason: a truncated sequence is what CheckJNI
+    /// rejects, and a track title is not worth a crash.
     static std::string escape(const char *text) {
         std::string out;
         if (!text) return out;
-        for (const unsigned char c : std::string_view(text)) {
+        const std::string_view input(text);
-            if (c == '"' || c == '\\') out += '\\';
+        for (size_t i = 0; i < input.size();) {
-            if (c >= 0x20) out += static_cast<char>(c);
+            const auto lead = static_cast<unsigned char>(input[i]);
+            size_t length = 0;
+            uint32_t code = 0;
+            if (lead < 0x80) {
+                length = 1;
+                code = lead;
+            } else if ((lead & 0xE0) == 0xC0) {
+                length = 2;
+                code = lead & 0x1Fu;
+            } else if ((lead & 0xF0) == 0xE0) {
+                length = 3;
+                code = lead & 0x0Fu;
+            } else if ((lead & 0xF8) == 0xF0) {
+                length = 4;
+                code = lead & 0x07u;
+            } else {
+                ++i; // A stray continuation or invalid lead byte.
+                continue;
+            }
+            if (i + length > input.size()) break;
+            bool valid = true;
+            for (size_t k = 1; k < length; ++k) {
+                const auto next = static_cast<unsigned char>(input[i + k]);
+                if ((next & 0xC0) != 0x80) {
+                    valid = false;
+                    break;
+                }
+                code = (code << 6) | (next & 0x3Fu);
+            }
+            if (!valid) {
+                ++i;
+                continue;
+            }
+            i += length;
+
+            if (code < 0x20) continue; // Control characters, including NUL.
+            if (code == '"' || code == '\\') {
+                out += '\\';
+                out += static_cast<char>(code);
+                continue;
+            }
+            if (code < 0x80) {
+                out += static_cast<char>(code);
+            } else if (code < 0x800) {
+                out += static_cast<char>(0xC0 | (code >> 6));
+                out += static_cast<char>(0x80 | (code & 0x3F));
+            } else if (code < 0x10000) {
+                append_three(out, code);
+            } else {
+                // The surrogate pair Modified UTF-8 wants, each half written as
+                // its own three-byte sequence.
+                const uint32_t rest = code - 0x10000;
+                append_three(out, 0xD800 + (rest >> 10));
+                append_three(out, 0xDC00 + (rest & 0x3FF));
+            }
         }
         return out;
     }
 
+    static void append_three(std::string &out, uint32_t code) {
+        out += static_cast<char>(0xE0 | (code >> 12));
+        out += static_cast<char>(0x80 | ((code >> 6) & 0x3F));
+        out += static_cast<char>(0x80 | (code & 0x3F));
+    }
+
     void option(const char *name, const char *value) { mpv_set_option_string(mpv_, name, value); }
     void observe(const char *name, uint64_t id, mpv_format format) { mpv_observe_property(mpv_, id, name, format); }
     void set_string(const char *name, const std::string &value) { mpv_set_property_string(mpv_, name, value.c_str()); }
@@ -304,27 +605,86 @@ class Player {
             if (event->event_id == MPV_EVENT_FILE_LOADED) {
                 const double start = pending_start_.exchange(0.0);
                 if (start > 0.0) set_double("time-pos", start);
+                std::vector<Subtitle> ready;
+                {
+                    std::lock_guard lock(state_mutex_);
+                    // Mid-load, this is the outgoing file finishing its load.
+                    if (!state_.loading) {
+                        loaded_generation_ = state_.generation;
+                        state_.loaded = true;
+                        ready.swap(pending_subtitles_);
+                    }
+                }
+                for (const auto &subtitle : ready) attach_subtitle(subtitle);
             }
             if (event->event_id == MPV_EVENT_END_FILE) {
+                const auto *end = static_cast<mpv_event_end_file *>(event->data);
                 std::lock_guard lock(state_mutex_);
+                // The end of the file `loadfile` is replacing, not of the one it
+                // is loading. Reporting it would hand every reader an episode
+                // that ended before it started.
+                if (state_.loading) continue;
                 state_.ended = true;
+                state_.end_reason = end ? end_reason_of(end->reason) : EndReason::Other;
             } else if (event->event_id == MPV_EVENT_START_FILE) {
                 std::lock_guard lock(state_mutex_);
+                state_.loading = false;
                 state_.ended = false;
+                state_.end_reason = EndReason::None;
+            } else if (event->event_id == MPV_EVENT_SEEK) {
+                std::lock_guard lock(state_mutex_);
+                state_.seeking = true;
+            } else if (event->event_id == MPV_EVENT_PLAYBACK_RESTART) {
+                // The seek is *visibly* done here, not when it was issued.
+                std::lock_guard lock(state_mutex_);
+                state_.seeking = false;
+            } else if (event->event_id == MPV_EVENT_LOG_MESSAGE) {
+                record_log(*static_cast<mpv_event_log_message *>(event->data));
             } else if (event->event_id == MPV_EVENT_PROPERTY_CHANGE) {
                 update_property(*static_cast<mpv_event_property *>(event->data));
             }
         }
     }
 
+    /// Keep the first error of the open file, not the last.
+    ///
+    /// A failure cascades — one unreadable header produces a dozen follow-on
+    /// complaints — and the first line is the one that names the cause. Cleared
+    /// by [take_error], which is how the UI consumes it.
+    ///
+    /// Only mpv's own errors. Everything libavcodec and libavformat complain
+    /// about arrives under an `ffmpeg/…` prefix, and mpv is the thing that
+    /// decides whether any of it mattered: a decoder that refuses to
+    /// initialise is an error there and a fallback here, so surfacing those
+    /// puts a dialog over a file that goes on to play perfectly. When one of
+    /// them really is fatal mpv says so itself, under a prefix of its own.
+    void record_log(const mpv_event_log_message &message) {
+        if (!message.text) return;
+        if (message.prefix && !std::strncmp(message.prefix, "ffmpeg", 6)) return;
+        std::lock_guard lock(state_mutex_);
+        if (!error_.empty()) return;
+        error_.assign(message.text);
+        while (!error_.empty() && (error_.back() == '\n' || error_.back() == '\r')) error_.pop_back();
+    }
+
     void update_property(const mpv_event_property &property) {
         if (!property.data) return;
         std::lock_guard lock(state_mutex_);
-        if (!std::strcmp(property.name, "time-pos")) state_.position = *static_cast<double *>(property.data);
+        // `volume`, `mute` and `pause` belong to the core and carry across a
-        else if (!std::strcmp(property.name, "duration")) state_.duration = *static_cast<double *>(property.data);
+        // load; the rest describe the open file, and a reading of them that
-        else if (!std::strcmp(property.name, "volume")) state_.volume = *static_cast<double *>(property.data);
+        // arrives mid-load is the outgoing episode's clock under the incoming
+        // episode's name.
+        if (!std::strcmp(property.name, "volume")) state_.volume = *static_cast<double *>(property.data);
         else if (!std::strcmp(property.name, "pause")) state_.paused = *static_cast<int *>(property.data);
         else if (!std::strcmp(property.name, "mute")) state_.muted = *static_cast<int *>(property.data);
+        else if (state_.loading) return;
+        else if (!std::strcmp(property.name, "time-pos")) state_.position = *static_cast<double *>(property.data);
+        else if (!std::strcmp(property.name, "duration")) state_.duration = *static_cast<double *>(property.data);
+        else if (!std::strcmp(property.name, "video-params/dw")) state_.video_width = static_cast<double>(*static_cast<int64_t *>(property.data));
+        else if (!std::strcmp(property.name, "video-params/dh")) state_.video_height = static_cast<double>(*static_cast<int64_t *>(property.data));
+        else if (!std::strcmp(property.name, "paused-for-cache")) state_.buffering = *static_cast<int *>(property.data);
+        else if (!std::strcmp(property.name, "cache-buffering-state")) state_.cache_percent = static_cast<double>(*static_cast<int64_t *>(property.data));
+        else if (!std::strcmp(property.name, "demuxer-cache-time")) state_.cached_until = *static_cast<double *>(property.data);
     }
 
     static void render_update(void *opaque) noexcept {
@@ -336,6 +696,15 @@ class Player {
         });
     }
 
+    /// Owns EGL and the mpv render context for the life of the player.
+    ///
+    /// Both are set up here rather than on the first surface attach, and neither
+    /// depends on there being a window: a pbuffer is enough to make a context
+    /// current, and `vo_libmpv` only needs *some* consumer. That is what makes
+    /// audio playback with no surface — the screen off, the app backgrounded —
+    /// structurally possible; before this, `load` waited five seconds for a
+    /// render context that only a visible SurfaceView could ever create, and
+    /// then failed.
     void render_loop() {
         EGLDisplay display = EGL_NO_DISPLAY;
         EGLContext context = EGL_NO_CONTEXT;
@@ -343,6 +712,7 @@ class Player {
         EGLSurface pbuffer = EGL_NO_SURFACE;
         EGLConfig config = nullptr;
         ANativeWindow *window = nullptr;
+        if (initialize_egl(display, context, config, pbuffer)) initialize_renderer();
         while (running_.load()) {
             std::unique_lock lock(render_mutex_);
             render_cv_.wait(lock, [this] { return !running_.load() || surface_changed_ || frame_ready_.load(); });
@@ -353,18 +723,31 @@ class Player {
                 if (window) ANativeWindow_release(window);
                 window = pending_window_;
                 pending_window_ = nullptr;
-                if (window && display == EGL_NO_DISPLAY && !initialize_egl(display, context, config, pbuffer)) {
+                if (window && display == EGL_NO_DISPLAY) {
+                    // EGL failed at startup and playback is audio-only. Keep the
+                    // window rather than the surface: nothing here can retry.
                     ANativeWindow_release(window);
                     window = nullptr;
                 }
                 if (window) {
                     surface = eglCreateWindowSurface(display, config, window, nullptr);
                     eglMakeCurrent(display, surface, surface, context);
-                    initialize_renderer();
                 }
             }
             const bool draw = frame_ready_.exchange(false);
             lock.unlock();
+            // With no window there is still a frame to consume. `vo_libmpv`
+            // expects its host to keep draining, and a video thread with no
+            // consumer stalls — which is why video came back out of sync with
+            // audio after the screen had been off.
+            if (draw && surface == EGL_NO_SURFACE && render_) {
+                eglMakeCurrent(display, pbuffer, pbuffer, context);
+                if (mpv_render_context_update(render_) & MPV_RENDER_UPDATE_FRAME) {
+                    int skip = 1;
+                    mpv_render_param params[] = {{MPV_RENDER_PARAM_SKIP_RENDERING, &skip}, {MPV_RENDER_PARAM_INVALID, nullptr}};
+                    mpv_render_context_render(render_, params);
+                }
+            }
             if (draw && surface != EGL_NO_SURFACE && render_) {
                 eglMakeCurrent(display, surface, surface, context);
                 if (mpv_render_context_update(render_) & MPV_RENDER_UPDATE_FRAME) {
@@ -394,18 +777,40 @@ class Player {
         if (pending_window_) { ANativeWindow_release(pending_window_); pending_window_ = nullptr; }
     }
 
+    /// All of EGL, or none of it.
+    ///
+    /// Leaving a display initialised behind a failed context is what made a
+    /// partial failure permanent: the retry guard is "is there a display", so a
+    /// half-built state reads as success forever and every later attach uses an
+    /// uninitialised config and `EGL_NO_CONTEXT`. Unwinding here keeps the guard
+    /// honest, and `eglGetError` says which step failed instead of leaving a
+    /// black screen with nothing in the log.
     bool initialize_egl(EGLDisplay &display, EGLContext &context, EGLConfig &config, EGLSurface &pbuffer) {
+        const auto fail = [&](const char *step) {
+            __android_log_print(ANDROID_LOG_ERROR, "pstr-mpv", "%s failed: 0x%04x", step, eglGetError());
+            if (pbuffer != EGL_NO_SURFACE) eglDestroySurface(display, pbuffer);
+            if (context != EGL_NO_CONTEXT) eglDestroyContext(display, context);
+            if (display != EGL_NO_DISPLAY) eglTerminate(display);
+            display = EGL_NO_DISPLAY;
+            context = EGL_NO_CONTEXT;
+            pbuffer = EGL_NO_SURFACE;
+            config = nullptr;
+            return false;
+        };
         display = eglGetDisplay(EGL_DEFAULT_DISPLAY);
-        if (display == EGL_NO_DISPLAY || !eglInitialize(display, nullptr, nullptr)) return false;
+        if (display == EGL_NO_DISPLAY) return fail("eglGetDisplay");
+        if (!eglInitialize(display, nullptr, nullptr)) return fail("eglInitialize");
         const EGLint attributes[] = {EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT, EGL_SURFACE_TYPE, EGL_WINDOW_BIT | EGL_PBUFFER_BIT, EGL_RED_SIZE, 8, EGL_GREEN_SIZE, 8, EGL_BLUE_SIZE, 8, EGL_NONE};
         EGLint count = 0;
-        if (!eglChooseConfig(display, attributes, &config, 1, &count) || count == 0) return false;
+        if (!eglChooseConfig(display, attributes, &config, 1, &count) || count == 0) return fail("eglChooseConfig");
         const EGLint context_attributes[] = {EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE};
         context = eglCreateContext(display, config, EGL_NO_CONTEXT, context_attributes);
-        if (context == EGL_NO_CONTEXT) return false;
+        if (context == EGL_NO_CONTEXT) return fail("eglCreateContext");
         const EGLint pbuffer_attributes[] = {EGL_WIDTH, 1, EGL_HEIGHT, 1, EGL_NONE};
         pbuffer = eglCreatePbufferSurface(display, config, pbuffer_attributes);
-        return pbuffer != EGL_NO_SURFACE && eglMakeCurrent(display, pbuffer, pbuffer, context);
+        if (pbuffer == EGL_NO_SURFACE) return fail("eglCreatePbufferSurface");
+        if (!eglMakeCurrent(display, pbuffer, pbuffer, context)) return fail("eglMakeCurrent");
+        return true;
     }
 
     void initialize_renderer() {
@@ -426,12 +831,20 @@ class Player {
     std::thread renderer_;
     mutable std::mutex state_mutex_;
     PlaybackState state_;
+    /// The first error mpv logged about the open file, until it is consumed.
+    std::string error_;
     std::mutex render_mutex_;
     std::condition_variable render_cv_;
     ANativeWindow *pending_window_ = nullptr;
     bool surface_changed_ = false;
     std::atomic<bool> frame_ready_{false};
     std::atomic<double> pending_start_{0.0};
+    /// The load generation whose file mpv has loaded, under `state_mutex_`.
+    int64_t loaded_generation_ = -1;
+    /// Subtitles handed over before their file loaded, under `state_mutex_`.
+    std::vector<Subtitle> pending_subtitles_;
+    /// Streams to release once `state_mutex_` is let go.
+    std::vector<uint64_t> released_;
 };
 
 Player *from(jlong handle) { return reinterpret_cast<Player *>(handle); }
@@ -465,13 +878,33 @@ bool utf8(JNIEnv *env, jstring value, std::string &result) {
 void reject_null_surface(JNIEnv *env) noexcept {
     c_boundary([=] {
         jclass type = env->FindClass("java/lang/IllegalArgumentException");
-        if (type) env->ThrowNew(type, "surface must not be null");
+        if (!type) return;
+        env->ThrowNew(type, "surface must not be null");
+        // FindClass hands back a local reference, and this is called from a
+        // long-lived attached thread where the frame is not popped for us.
+        env->DeleteLocalRef(type);
     });
 }
 
 } // namespace
 
-extern "C" JNIEXPORT jlong JNICALL Java_io_narl_protonstream_playback_NativeMpvHost_nativeCreate(JNIEnv *, jobject) noexcept {
+/// FFmpeg's MediaCodec decoders call into Android's Java API, and they can only
+/// reach it through a JavaVM handed to them explicitly — there is no way for
+/// them to discover one. Without this, every hardware decoder fails to open
+/// with "hevc_mediacodec: No Java virtual machine has been registered" and
+/// playback falls back to software decoding, which on a phone means a hot
+/// device and dropped frames on anything above 1080p.
+///
+/// mpv-android's own JNI layer does this in its `create` entry point; this
+/// library replaces that layer, so the registration has to happen here. The
+/// loader calls this once per process before any native method, which is
+/// earlier than any decoder can run.
+extern "C" JNIEXPORT jint JNICALL JNI_OnLoad(JavaVM *vm, void *) {
+    av_jni_set_java_vm(vm, nullptr);
+    return JNI_VERSION_1_6;
+}
+
+extern "C" JNIEXPORT jlong JNICALL Java_io_narl_protonstream_playback_NativeMpvHost_nativeCreate(JNIEnv *, jclass) noexcept {
     return c_boundary<jlong>(0, [] {
         auto player = std::make_unique<Player>();
         return player->valid() ? reinterpret_cast<jlong>(player.release()) : 0;
@@ -489,7 +922,7 @@ extern "C" JNIEXPORT void JNICALL Java_io_narl_protonstream_playback_NativeMpvHo
 extern "C" JNIEXPORT void JNICALL Java_io_narl_protonstream_playback_NativeMpvHost_nativeDetachSurface(JNIEnv *, jobject, jlong handle) noexcept {
     c_boundary([=] { if (auto *p = from(handle)) p->detach(); });
 }
-extern "C" JNIEXPORT jboolean JNICALL Java_io_narl_protonstream_playback_NativeMpvHost_nativeLoad(JNIEnv *env, jobject, jlong handle, jlong stream, jdouble start, jstring audio, jstring subtitle, jboolean subtitles) noexcept {
+extern "C" JNIEXPORT jboolean JNICALL Java_io_narl_protonstream_playback_NativeMpvHost_nativeLoad(JNIEnv *env, jobject, jlong handle, jlong stream, jdouble start, jstring audio, jstring subtitle, jboolean subtitles, jboolean hardware_decoding) noexcept {
     return c_boundary<jboolean>(JNI_FALSE, [=] {
         std::string audio_text;
         std::string subtitle_text;
@@ -499,11 +932,23 @@ extern "C" JNIEXPORT jboolean JNICALL Java_io_narl_protonstream_playback_NativeM
         auto *p = from(handle);
         return static_cast<jboolean>(
             p && p->load(static_cast<uint64_t>(stream), start, audio_text,
-                         subtitle_text, subtitles == JNI_TRUE)
+                         subtitle_text, subtitles == JNI_TRUE,
+                         hardware_decoding == JNI_TRUE)
                 ? JNI_TRUE
                 : JNI_FALSE);
     });
 }
+extern "C" JNIEXPORT void JNICALL Java_io_narl_protonstream_playback_NativeMpvHost_nativeAddSubtitle(JNIEnv *env, jobject, jlong handle, jlong generation, jlong stream, jstring title, jstring language, jboolean select) noexcept {
+    c_boundary([=] {
+        Subtitle subtitle{static_cast<uint64_t>(stream), {}, {}, select == JNI_TRUE};
+        auto *p = from(handle);
+        if (!p || !utf8(env, title, subtitle.title) || !utf8(env, language, subtitle.language)) {
+            pstr_android_stream_release(subtitle.handle);
+            return;
+        }
+        p->add_subtitle(generation, std::move(subtitle));
+    });
+}
 extern "C" JNIEXPORT void JNICALL Java_io_narl_protonstream_playback_NativeMpvHost_nativePause(JNIEnv *, jobject, jlong h, jboolean value) noexcept {
     c_boundary([=] { if (auto *p = from(h)) p->pause(value == JNI_TRUE); });
 }
@@ -513,6 +958,9 @@ extern "C" JNIEXPORT void JNICALL Java_io_narl_protonstream_playback_NativeMpvHo
 extern "C" JNIEXPORT void JNICALL Java_io_narl_protonstream_playback_NativeMpvHost_nativeVolume(JNIEnv *, jobject, jlong h, jdouble value) noexcept {
     c_boundary([=] { if (auto *p = from(h)) p->volume(value); });
 }
+extern "C" JNIEXPORT void JNICALL Java_io_narl_protonstream_playback_NativeMpvHost_nativeSpeed(JNIEnv *, jobject, jlong h, jdouble value) noexcept {
+    c_boundary([=] { if (auto *p = from(h)) p->speed(value); });
+}
 extern "C" JNIEXPORT void JNICALL Java_io_narl_protonstream_playback_NativeMpvHost_nativeMute(JNIEnv *, jobject, jlong h, jboolean value) noexcept {
     c_boundary([=] { if (auto *p = from(h)) p->mute(value == JNI_TRUE); });
 }
@@ -527,19 +975,39 @@ extern "C" JNIEXPORT jdoubleArray JNICALL Java_io_narl_protonstream_playback_Nat
         const auto state = from(h) ? from(h)->state() : PlaybackState{};
         const jdouble values[] = {state.position, state.duration, state.volume,
                                   state.paused ? 1.0 : 0.0, state.muted ? 1.0 : 0.0,
-                                  state.ended ? 1.0 : 0.0};
+                                  state.ended ? 1.0 : 0.0,
-        jdoubleArray result = env->NewDoubleArray(6);
+                                  static_cast<jdouble>(state.generation),
+                                  state.video_width, state.video_height,
+                                  static_cast<jdouble>(state.end_reason),
+                                  state.buffering ? 1.0 : 0.0, state.cache_percent,
+                                  state.seeking ? 1.0 : 0.0, state.cached_until,
+                                  state.loaded ? 1.0 : 0.0};
+        constexpr jsize kFields = 15;
+        jdoubleArray result = env->NewDoubleArray(kFields);
         if (!result) return static_cast<jdoubleArray>(nullptr);
-        env->SetDoubleArrayRegion(result, 0, 6, values);
+        env->SetDoubleArrayRegion(result, 0, kFields, values);
         if (env->ExceptionCheck()) return static_cast<jdoubleArray>(nullptr);
         return result;
     });
 }
+extern "C" JNIEXPORT jstring JNICALL Java_io_narl_protonstream_playback_NativeMpvHost_nativeTakeError(JNIEnv *env, jobject, jlong h) noexcept {
+    return c_boundary<jstring>(nullptr, [=]() -> jstring {
+        auto *player = from(h);
+        if (!player) return nullptr;
+        const std::string error = player->take_error();
+        return error.empty() ? nullptr : string(env, error);
+    });
+}
 extern "C" JNIEXPORT jstring JNICALL Java_io_narl_protonstream_playback_NativeMpvHost_nativeTracks(JNIEnv *env, jobject, jlong h) noexcept {
     return c_boundary<jstring>(nullptr, [=] {
         return string(env, from(h) ? from(h)->tracks_json() : "[]");
     });
 }
+extern "C" JNIEXPORT jstring JNICALL Java_io_narl_protonstream_playback_NativeMpvHost_nativeChapters(JNIEnv *env, jobject, jlong h) noexcept {
+    return c_boundary<jstring>(nullptr, [=] {
+        return string(env, from(h) ? from(h)->chapters_json() : "[]");
+    });
+}
 extern "C" JNIEXPORT void JNICALL Java_io_narl_protonstream_playback_NativeMpvHost_pstrAndroidStreamRelease(JNIEnv *, jobject, jlong handle) noexcept {
     c_boundary([=] { pstr_android_stream_release(static_cast<uint64_t>(handle)); });
 }

android/app/src/main/cpp/pstr_mpv.h

@@ -8,6 +8,9 @@ extern "C" {
 #endif
 int64_t pstr_android_stream_read(uint64_t handle, uint64_t offset, void *buffer, size_t length);
 int64_t pstr_android_stream_size(uint64_t handle);
+/// Interrupts an in-flight `pstr_android_stream_read`. A cancel with no reader
+/// waiting is dropped, so this is safe to call speculatively.
+void pstr_android_stream_cancel(uint64_t handle);
 void pstr_android_stream_release(uint64_t handle);
 #ifdef __cplusplus
 }

android/app/src/main/java/io/narl/protonstream/IncomingShareLink.kt

@@ -0,0 +1,22 @@
+package io.narl.protonstream
+
+import android.content.Intent
+
+/**
+ * A Proton Drive public link, wherever in a piece of text it sits.
+ *
+ * The fragment is kept: it is the share's secret, and a link without it cannot
+ * be opened. Matching stops at whitespace and at the quotes and brackets a
+ * message app wraps a link in, which never occur in a link itself.
+ */
+private val SHARE_LINK = Regex("""https://drive\.proton\.me/urls/[^\s"'<>()\[\]]+""")
+
+/** The share link an `ACTION_VIEW` URL or an `ACTION_SEND` text carries, if any. */
+internal fun shareLinkFrom(action: String?, url: String?, text: CharSequence?): String? = when (action) {
+    Intent.ACTION_VIEW -> url?.let { SHARE_LINK.matchEntire(it)?.value }
+    Intent.ACTION_SEND -> text?.let { SHARE_LINK.find(it)?.value }
+    else -> null
+}
+
+internal fun Intent.shareLink(): String? =
+    shareLinkFrom(action, dataString, getCharSequenceExtra(Intent.EXTRA_TEXT))

android/app/src/main/java/io/narl/protonstream/MainActivity.kt

@@ -1,48 +1,86 @@
 package io.narl.protonstream
 
 import android.Manifest
-import android.content.pm.PackageManager
-import android.os.Bundle
-import android.os.Build
-import android.app.PictureInPictureParams
 import android.content.ComponentName
 import android.content.Context
 import android.content.Intent
 import android.content.ServiceConnection
+import android.content.pm.PackageManager
+import android.os.Build
+import android.os.Bundle
 import android.os.IBinder
-import android.util.Rational
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
 import androidx.activity.enableEdgeToEdge
 import androidx.activity.result.contract.ActivityResultContracts
-import io.narl.protonstream.ui.ProtonStreamApp
+import androidx.compose.runtime.mutableStateOf
-import io.narl.protonstream.ui.theme.ProtonStreamTheme
+import androidx.core.graphics.drawable.toDrawable
+import androidx.core.view.WindowCompat
+import androidx.lifecycle.lifecycleScope
+import io.narl.protonstream.native.NativeRuntime
 import io.narl.protonstream.playback.NativeMpvHost
 import io.narl.protonstream.playback.PlaybackService
-import androidx.compose.runtime.mutableStateOf
 import io.narl.protonstream.settings.SettingsStore
+import io.narl.protonstream.sync.NewEpisodesWorker
+import io.narl.protonstream.sync.WatchSyncWorker
+import io.narl.protonstream.ui.ProtonStreamApp
+import io.narl.protonstream.ui.theme.AppearanceState
+import io.narl.protonstream.ui.theme.ProtonStreamTheme
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.filterNotNull
+import kotlinx.coroutines.launch
+import uniffi.pstr_android.PaletteRecord
 
 class MainActivity : ComponentActivity() {
     private val playerHost = mutableStateOf<NativeMpvHost?>(null)
+
+    /** A share link handed over by a browser or the share sheet, until the Add form takes it. */
+    private val incomingShareLink = mutableStateOf<String?>(null)
+    /**
+     * Whether a bind is outstanding, which is what has to be unbound.
+     *
+     * Set when `bindService` is called rather than when the connection arrives:
+     * an activity destroyed while the bind is still pending owes the system an
+     * `unbindService` just the same, and `onServiceConnected` may never run.
+     */
     private var bound = false
     private val playbackConnection = object : ServiceConnection {
         override fun onServiceConnected(name: ComponentName?, service: IBinder?) {
             playerHost.value = (service as PlaybackService.PlaybackBinder).host
-            bound = true
         }
         override fun onServiceDisconnected(name: ComponentName?) {
             playerHost.value = null
-            bound = false
         }
     }
+
     private val notificationPermission = registerForActivityResult(
         ActivityResultContracts.RequestPermission(),
     ) { /* Downloads remain usable; Android suppresses their notifications if denied. */ }
 
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
+        // Before anything draws. The palette decides the window's own
+        // background and which way round the system bars' icons go, and both
+        // are wrong for a frame if they are set from a composition instead.
+        // Infallible by construction — an unreadable theme file resolves to the
+        // shipped default rather than throwing.
+        runCatching { NativeRuntime.storedPalette() }.onSuccess(AppearanceState::seed)
+        // Only on a fresh start: a recreated activity is handed the intent it
+        // was launched with again, and would offer to add the same share twice.
+        if (savedInstanceState == null) incomingShareLink.value = intent.shareLink()
         enableEdgeToEdge()
-        bindService(Intent(this, PlaybackService::class.java), playbackConnection, Context.BIND_AUTO_CREATE)
+        // Re-applied on every change, not just at startup: picking Latte from
+        // the settings page has to turn the status bar's icons dark in the same
+        // frame the page behind them turns light.
+        lifecycleScope.launch {
+            AppearanceState.palette.filterNotNull().distinctUntilChanged().collect(::dressWindow)
+        }
+        bound = bindService(
+            Intent(this, PlaybackService::class.java),
+            playbackConnection,
+            Context.BIND_AUTO_CREATE,
+        )
+        NewEpisodesWorker.schedule(this)
         if (
             Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU &&
             checkSelfPermission(Manifest.permission.POST_NOTIFICATIONS) != PackageManager.PERMISSION_GRANTED
@@ -51,30 +89,57 @@ class MainActivity : ComponentActivity() {
         }
         setContent {
             ProtonStreamTheme {
-                ProtonStreamApp(playerHost.value)
+                ProtonStreamApp(
+                    playerHost.value,
+                    shareLink = incomingShareLink.value,
+                    onShareLinkTaken = { incomingShareLink.value = null },
+                )
             }
         }
     }
 
-    override fun onUserLeaveHint() {
+    /**
-        super.onUserLeaveHint()
+     * The parts of the window Compose does not reach: the background behind the
-        if (playerHost.value?.hasActivePlayback == true && !isInPictureInPictureMode) {
+     * whole activity, and the polarity of the system bars' icons.
-            enterPictureInPictureMode(
+     *
-                PictureInPictureParams.Builder().setAspectRatio(Rational(16, 9)).setAutoEnterEnabled(true).build(),
+     * The background matters for the frames before and between compositions —
-            )
+     * the launch frame, and a rotation. It used to be a hex literal in
+     * `themes.xml`, which meant every cold start showed a colour from one
+     * flavour regardless of which one was chosen.
+     *
+     * The icons matter because the app ships a light flavour. Pinned dark, as
+     * they were, Latte drew white status-bar icons onto a near-white page.
+     */
+    private fun dressWindow(palette: PaletteRecord) {
+        window.setBackgroundDrawable(palette.background.toInt().toDrawable())
+        WindowCompat.getInsetsController(window, window.decorView).apply {
+            isAppearanceLightStatusBars = palette.light
+            isAppearanceLightNavigationBars = palette.light
         }
     }
 
+    // singleTask: a link opened while the app is running arrives here, not in
+    // a second activity.
+    override fun onNewIntent(intent: Intent) {
+        super.onNewIntent(intent)
+        intent.shareLink()?.let { incomingShareLink.value = it }
+    }
+
     override fun onDestroy() {
-        if (bound) unbindService(playbackConnection)
+        if (bound) {
+            unbindService(playbackConnection)
+            bound = false
+        }
         super.onDestroy()
     }
 
     override fun onStop() {
         super.onStop()
+        // Where the viewer stopped is what their other devices want next, and
+        // a process in the background may not live to the next timed sync.
+        if (!isChangingConfigurations) WatchSyncWorker.enqueue(this)
         if (
             !isChangingConfigurations &&
-            !isInPictureInPictureMode &&
             !SettingsStore(this).backgroundAudio
         ) {
             playerHost.value?.stop()

android/app/src/main/java/io/narl/protonstream/ProtonStreamApplication.kt

@@ -2,10 +2,15 @@ package io.narl.protonstream
 
 import android.app.Application
 import io.narl.protonstream.native.NativeRuntime
+import io.narl.protonstream.settings.SettingsStore
 
 class ProtonStreamApplication : Application() {
     override fun onCreate() {
         super.onCreate()
         NativeRuntime.initialize(this)
+        // SharedPreferences reads its file on first use, and the first use was
+        // on the main thread — in the playback service's start callback among
+        // others. Read here, off it, and every later read is from memory.
+        Thread({ SettingsStore.preload(this) }, "settings-preload").start()
     }
 }

android/app/src/main/java/io/narl/protonstream/download/DownloadCoordinator.kt

@@ -1,37 +1,151 @@
 package io.narl.protonstream.download
 
 import android.content.Context
+import android.os.StatFs
 import androidx.work.Constraints
 import androidx.work.ExistingWorkPolicy
 import androidx.work.NetworkType
+import androidx.work.OneTimeWorkRequest
 import androidx.work.OneTimeWorkRequestBuilder
 import androidx.work.WorkManager
 import androidx.work.workDataOf
 import io.narl.protonstream.settings.SettingsStore
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.SupervisorJob
+import kotlinx.coroutines.launch
 import uniffi.pstr_android.EpisodeRecord
 
 object DownloadCoordinator {
-    fun enqueue(context: Context, episode: EpisodeRecord) {
+    /**
-        enqueue(
+     * Where bulk queueing runs.
-            context,
+     *
-            RetainedDownload(episode.shareId, episode.volumeId, episode.linkId, episode.label),
+     * Callers are click handlers, and "Download show" on a long series is a
-            ExistingWorkPolicy.KEEP,
+     * WorkManager enqueue per episode — each of which writes to its own
-        )
+     * database. On the main thread that is an ANR waiting for a long enough
-    }
+     * series.
+     */
+    private val queueing = CoroutineScope(SupervisorJob() + Dispatchers.IO)
+
+    fun enqueue(context: Context, episode: EpisodeRecord) = enqueue(context, listOf(episode))
 
     fun resume(context: Context, download: RetainedDownload) {
         enqueue(context, download, ExistingWorkPolicy.REPLACE)
     }
 
     private fun enqueue(context: Context, download: RetainedDownload, policy: ExistingWorkPolicy) {
-        DownloadStateStore(context).put(
+        val queued = download.copy(status = RetainedDownload.STATUS_QUEUED, error = null)
-            download.copy(status = RetainedDownload.STATUS_QUEUED, error = null),
+        DownloadStateStore(context).put(queued)
+        WorkManager.getInstance(context).enqueueUniqueWork(
+            workName(download.shareId, download.linkId),
+            policy,
+            request(queued, SettingsStore(context).wifiOnly),
         )
-        val request = OneTimeWorkRequestBuilder<OfflineDownloadWorker>()
+    }
+
+    fun enqueue(context: Context, episodes: Iterable<EpisodeRecord>) {
+        val wanted = episodes.filterNot(EpisodeRecord::offline).toList()
+        if (wanted.isEmpty()) return
+        val application = context.applicationContext
+        queueing.launch {
+            val wifiOnly = SettingsStore(application).wifiOnly
+            val store = DownloadStateStore(application)
+            val manager = WorkManager.getInstance(application)
+            // Space is checked once for the whole request, against its total.
+            // Queueing a season that cannot fit and discovering it episode by
+            // episode at ENOSPC is how the app fills its own database's disk.
+            val room = roomFor(application, wanted.sumOf { it.size?.toLong() ?: 0L })
+            val downloads = wanted.map { episode ->
+                RetainedDownload(
+                    episode.shareId,
+                    episode.volumeId,
+                    episode.linkId,
+                    episode.label,
+                    total = episode.size?.toLong() ?: 0L,
+                    status = if (room) RetainedDownload.STATUS_QUEUED else RetainedDownload.STATUS_FAILED,
+                    error = if (room) null else "Not enough free space",
+                )
+            }
+            store.putAll(downloads)
+            if (!room) return@launch
+            downloads.forEach { download ->
+                manager.enqueueUniqueWork(
+                    workName(download.shareId, download.linkId),
+                    ExistingWorkPolicy.KEEP,
+                    request(download, wifiOnly),
+                )
+            }
+        }
+    }
+
+    /**
+     * Whether [bytes] plus working room will fit where offline files are kept.
+     *
+     * `setRequiresStorageNotLow` only holds work back at Android's own low-storage
+     * threshold, which a single episode can cross on its own. An unknown size —
+     * zero — is allowed through: refusing a download because the catalog has no
+     * size for it would be worse than the ENOSPC it is guarding against.
+     */
+    private fun roomFor(context: Context, bytes: Long): Boolean {
+        if (bytes <= 0) return true
+        val available = runCatching { StatFs(context.filesDir.path).availableBytes }.getOrNull() ?: return true
+        return available - bytes >= STORAGE_HEADROOM
+    }
+
+    /**
+     * Re-apply the network constraint to work that is already queued.
+     *
+     * Constraints are baked in at enqueue time, so turning "Wi-Fi only" on after
+     * queueing a season did nothing to that season — it downloaded over cellular
+     * on the way out of the house, which is the one moment the setting exists
+     * for. Running work is left alone: WorkManager stops it on its own when the
+     * new constraint stops being met.
+     */
+    fun applyNetworkPolicy(context: Context) {
+        val application = context.applicationContext
+        queueing.launch {
+            val wifiOnly = SettingsStore(application).wifiOnly
+            val manager = WorkManager.getInstance(application)
+            DownloadStateStore(application).records()
+                .filter { it.status == RetainedDownload.STATUS_QUEUED || it.status == RetainedDownload.STATUS_RUNNING }
+                .forEach { download ->
+                    manager.enqueueUniqueWork(
+                        workName(download.shareId, download.linkId),
+                        ExistingWorkPolicy.REPLACE,
+                        request(download, wifiOnly),
+                    )
+                }
+        }
+    }
+
+    fun pause(context: Context, download: RetainedDownload) =
+        setStatus(context, download, RetainedDownload.STATUS_PAUSED)
+
+    fun cancel(context: Context, download: RetainedDownload) =
+        setStatus(context, download, RetainedDownload.STATUS_CANCELLED)
+
+    /**
+     * The status write goes before the work is cancelled, and through `update`
+     * rather than `put`: the running worker is writing progress into the same
+     * record, and a whole-record `put` from a screen's stale copy would both
+     * lose that progress and race the worker's own read-modify-write.
+     */
+    private fun setStatus(context: Context, download: RetainedDownload, status: String) {
+        DownloadStateStore(context).update(download.shareId, download.linkId) { stored ->
+            (stored ?: download).copy(status = status, error = null)
+        }
+        WorkManager.getInstance(context).cancelUniqueWork(workName(download.shareId, download.linkId))
+    }
+
+    private fun request(download: RetainedDownload, wifiOnly: Boolean): OneTimeWorkRequest =
+        OneTimeWorkRequestBuilder<OfflineDownloadWorker>()
             .setConstraints(
-                Constraints.Builder().setRequiredNetworkType(
+                Constraints.Builder()
-                    requiredNetworkType(SettingsStore(context).wifiOnly),
+                    .setRequiredNetworkType(requiredNetworkType(wifiOnly))
-                ).build(),
+                    // A download that fills the disk takes the app's own
+                    // database down with it; the `.part` file makes waiting free.
+                    .setRequiresStorageNotLow(true)
+                    .build(),
             )
             .setInputData(
                 workDataOf(
@@ -45,26 +159,6 @@ object DownloadCoordinator {
             .addTag("$EPISODE_TAG${download.label}")
             .addTag(shareTag(download.shareId))
             .build()
-        WorkManager.getInstance(context).enqueueUniqueWork(
-            workName(download.shareId, download.linkId),
-            policy,
-            request,
-        )
-    }
-
-    fun enqueue(context: Context, episodes: Iterable<EpisodeRecord>) {
-        episodes.filterNot(EpisodeRecord::offline).forEach { enqueue(context, it) }
-    }
-
-    fun pause(context: Context, download: RetainedDownload) {
-        DownloadStateStore(context).put(download.copy(status = RetainedDownload.STATUS_PAUSED, error = null))
-        WorkManager.getInstance(context).cancelUniqueWork(workName(download.shareId, download.linkId))
-    }
-
-    fun cancel(context: Context, download: RetainedDownload) {
-        DownloadStateStore(context).put(download.copy(status = RetainedDownload.STATUS_CANCELLED))
-        WorkManager.getInstance(context).cancelUniqueWork(workName(download.shareId, download.linkId))
-    }
 
     fun shareTag(shareId: String) = "$SHARE_TAG$shareId"
     fun workName(shareId: String, linkId: String) = "offline-$shareId-$linkId"
@@ -72,6 +166,9 @@ object DownloadCoordinator {
     const val TAG = "offline-download"
     const val EPISODE_TAG = "offline-episode:"
     private const val SHARE_TAG = "offline-share:"
+
+    /** Free space to leave behind a download, for the catalog and the caches. */
+    private const val STORAGE_HEADROOM = 256L * 1024 * 1024
 }
 
 internal fun requiredNetworkType(wifiOnly: Boolean): NetworkType =

android/app/src/main/java/io/narl/protonstream/download/DownloadStateStore.kt

@@ -13,6 +13,8 @@ data class RetainedDownload(
     val total: Long = 0,
     val status: String = STATUS_QUEUED,
     val error: String? = null,
+    /** Recent transfer rate while running; 0 when unknown or not running. */
+    val bytesPerSecond: Long = 0,
 ) {
     val key: String get() = "$shareId\u001f$linkId"
 
@@ -35,18 +37,59 @@ class DownloadStateStore(context: Context) {
     fun get(shareId: String, linkId: String): RetainedDownload? =
         preferences.getString(key(shareId, linkId), null)?.let { runCatching { decode(it) }.getOrNull() }
 
-    fun put(record: RetainedDownload) {
+    fun put(record: RetainedDownload) = synchronized(WRITES) {
-        preferences.edit().putString(record.key, encode(record)).commit()
+        edit { putString(record.key, encode(record)) }
     }
 
-    fun remove(shareId: String, linkId: String) {
+    /**
-        preferences.edit().remove(key(shareId, linkId)).commit()
+     * Read-modify-write one record, excluding every other writer.
+     *
+     * The worker's progress update reads the stored record to decide whether the
+     * viewer has paused, then writes it back. `pause()` is another writer, and
+     * without this a `put` landing between those two halves puts `RUNNING` back
+     * over `PAUSED` — after which the worker's own cancellation handler sees a
+     * status that is not `PAUSED` and records `CANCELLED`. The pause is simply
+     * lost, which is the visible bug.
+     *
+     * Returning null from [change] leaves the record alone.
+     */
+    fun update(shareId: String, linkId: String, change: (RetainedDownload?) -> RetainedDownload?) =
+        synchronized(WRITES) {
+            change(get(shareId, linkId))?.let { edit { putString(it.key, encode(it)) } }
+        }
+
+    /**
+     * Write a whole queue in one go.
+     *
+     * Queueing a season is one call, not one per episode: `commit()` per record
+     * on a 200-episode series was 200 synchronous fsyncs, and the callers are
+     * click handlers.
+     */
+    fun putAll(records: Collection<RetainedDownload>) = synchronized(WRITES) {
+        edit { records.forEach { putString(it.key, encode(it)) } }
     }
 
-    fun removeShare(shareId: String) {
+    fun remove(shareId: String, linkId: String) = synchronized(WRITES) {
-        val edit = preferences.edit()
+        edit { remove(key(shareId, linkId)) }
-        records().filter { it.shareId == shareId }.forEach { edit.remove(it.key) }
+    }
-        edit.commit()
+
+    /** Forget every retained download. Callers cancel the work first. */
+    fun clear() = synchronized(WRITES) { edit { clear() } }
+
+    fun removeShare(shareId: String) = synchronized(WRITES) {
+        edit { records().filter { it.shareId == shareId }.forEach { remove(it.key) } }
+    }
+
+    /**
+     * `apply()`, not `commit()`.
+     *
+     * The in-memory map is updated before this returns, so a read that follows a
+     * write in the same process still sees it; only the disk write is deferred,
+     * and losing the newest progress reading to a kill is not worth an fsync on
+     * whichever thread happened to be writing.
+     */
+    private inline fun edit(block: android.content.SharedPreferences.Editor.() -> Unit) {
+        preferences.edit().apply(block).apply()
     }
 
     private fun encode(record: RetainedDownload) = JSONObject()
@@ -58,6 +101,7 @@ class DownloadStateStore(context: Context) {
         .put("total", record.total)
         .put("status", record.status)
         .put("error", record.error)
+        .put("rate", record.bytesPerSecond)
         .toString()
 
     private fun decode(encoded: String): RetainedDownload {
@@ -71,6 +115,7 @@ class DownloadStateStore(context: Context) {
             total = json.optLong("total"),
             status = json.optString("status", RetainedDownload.STATUS_QUEUED),
             error = json.optString("error").takeIf(String::isNotBlank),
+            bytesPerSecond = json.optLong("rate"),
         )
     }
 
@@ -78,5 +123,11 @@ class DownloadStateStore(context: Context) {
 
     private companion object {
         const val NAME = "offline_download_state"
+
+        /**
+         * One lock for the whole process. Instances of this class are created
+         * ad hoc from a `Context`, so the lock cannot live on one of them.
+         */
+        val WRITES = Any()
     }
 }

android/app/src/main/java/io/narl/protonstream/download/OfflineDownloadWorker.kt

@@ -1,10 +1,15 @@
 package io.narl.protonstream.download
 
+import android.Manifest
 import android.app.NotificationChannel
 import android.app.NotificationManager
+import android.content.pm.PackageManager
 import android.content.pm.ServiceInfo
 import android.content.Context
+import android.os.Build
+import android.os.SystemClock
 import androidx.core.app.NotificationCompat
+import androidx.core.content.ContextCompat
 import androidx.work.CoroutineWorker
 import androidx.work.Data
 import androidx.work.ForegroundInfo
@@ -23,32 +28,77 @@ class OfflineDownloadWorker(
     parameters: WorkerParameters,
 ) : CoroutineWorker(appContext, parameters) {
     override suspend fun doWork(): Result {
-        setForeground(createForegroundInfo(0))
+        createNotificationChannel()
         val shareId = inputData.getString(KEY_SHARE_ID) ?: return Result.failure(error("missing share"))
         val volumeId = inputData.getString(KEY_VOLUME_ID) ?: return Result.failure(error("missing volume"))
         val linkId = inputData.getString(KEY_LINK_ID) ?: return Result.failure(error("missing link"))
         val label = inputData.getString(KEY_LABEL) ?: linkId
         val store = DownloadStateStore(applicationContext)
+        setForeground(createForegroundInfo(label, null))
+        postSummary(store)
+        try {
+            return transfer(store, shareId, volumeId, linkId, label)
+        } finally {
+            postSummary(store)
+        }
+    }
+
+    private suspend fun transfer(
+        store: DownloadStateStore,
+        shareId: String,
+        volumeId: String,
+        linkId: String,
+        label: String,
+    ): Result {
+        // Queued, not running: the engine lets two downloads transfer at once
+        // and holds the rest back, and only the first progress report means
+        // this one has a slot.
         var retained = store.get(shareId, linkId)
             ?: RetainedDownload(shareId, volumeId, linkId, label)
-        retained = retained.copy(status = RetainedDownload.STATUS_RUNNING, error = null)
+        retained = retained.copy(status = RetainedDownload.STATUS_QUEUED, error = null, bytesPerSecond = 0)
         store.put(retained)
 
         val observer = object : DownloadObserver {
+            private var reportedAt = 0L
+            private var reportedPercent = -1
+            private val rate = TransferRate()
+
+            /**
+             * Called once per 4 MiB block — a dozen times a second on a fast
+             * link, each one a WorkManager database write, a notification post
+             * and a preferences write. Nothing the viewer can see changes that
+             * often, so a report is only made when the percentage moves or a
+             * second has passed. The final one is never suppressed.
+             */
             override fun onProgress(downloaded: ULong, total: ULong) {
                 val percent = if (total == 0UL) 0 else ((downloaded * 100UL) / total).toInt()
+                val now = SystemClock.elapsedRealtime()
+                val complete = total > 0UL && downloaded >= total
+                val bytesPerSecond = rate.sample(downloaded.toLong(), now)
+                if (!complete && percent == reportedPercent && now - reportedAt < PROGRESS_INTERVAL_MS) {
+                    return
+                }
+                reportedAt = now
+                reportedPercent = percent
                 setProgressAsync(workDataOf(KEY_DOWNLOADED to downloaded.toLong(), KEY_TOTAL to total.toLong()))
-                setForegroundAsync(createForegroundInfo(percent))
+                setForegroundAsync(createForegroundInfo(label, percent))
-                val requested = store.get(shareId, linkId)
+                // Under the store's lock: `pause()` is a concurrent writer, and
-                val requestedStatus = requested?.status
+                // this read-modify-write used to put RUNNING back over the
-                retained = (requested ?: retained).copy(
+                // viewer's PAUSED and then report the download as cancelled.
-                    downloaded = downloaded.toLong(),
+                store.update(shareId, linkId) { stored ->
-                    total = total.toLong(),
+                    val current = stored ?: retained
-                    status = if (requestedStatus == RetainedDownload.STATUS_PAUSED ||
+                    current.copy(
-                        requestedStatus == RetainedDownload.STATUS_CANCELLED
+                        downloaded = downloaded.toLong(),
-                    ) requestedStatus else RetainedDownload.STATUS_RUNNING,
+                        total = total.toLong(),
-                )
+                        bytesPerSecond = bytesPerSecond,
-                store.put(retained)
+                        status = when (current.status) {
+                            RetainedDownload.STATUS_PAUSED,
+                            RetainedDownload.STATUS_CANCELLED,
+                            -> current.status
+                            else -> RetainedDownload.STATUS_RUNNING
+                        },
+                    ).also { retained = it }
+                }
             }
 
             override fun isCancelled(): Boolean = isStopped
@@ -62,9 +112,12 @@ class OfflineDownloadWorker(
             },
             onFailure = { failure ->
                 if (isStopped) {
-                    val current = store.get(shareId, linkId) ?: retained
+                    // A pause is also a stop. Under the lock, so the record read
-                    if (current.status != RetainedDownload.STATUS_PAUSED) {
+                    // here is the one the write lands on.
-                        store.put(current.copy(status = RetainedDownload.STATUS_CANCELLED))
+                    store.update(shareId, linkId) { stored ->
+                        val current = stored ?: retained
+                        current.takeIf { it.status != RetainedDownload.STATUS_PAUSED }
+                            ?.copy(status = RetainedDownload.STATUS_CANCELLED)
                     }
                     Result.failure(error("cancelled"))
                 } else if (runAttemptCount < MAX_RETRIES) {
@@ -79,16 +132,27 @@ class OfflineDownloadWorker(
         )
     }
 
-    private fun createForegroundInfo(progress: Int): ForegroundInfo {
+    /** Once per run, rather than once per 4 MiB block. */
-        val manager = applicationContext.getSystemService(NotificationManager::class.java)
+    private fun createNotificationChannel() {
-        manager.createNotificationChannel(
+        applicationContext.getSystemService(NotificationManager::class.java).createNotificationChannel(
             NotificationChannel(CHANNEL_ID, "Offline downloads", NotificationManager.IMPORTANCE_LOW),
         )
+    }
+
+    /**
+     * This episode's line, under [GROUP]: a season is fourteen workers, and
+     * fourteen loose notifications saying the same thing named nothing.
+     * [progress] is a percentage, or null while waiting for a download slot.
+     */
+    private fun createForegroundInfo(label: String, progress: Int?): ForegroundInfo {
         val notification = NotificationCompat.Builder(applicationContext, CHANNEL_ID)
             .setSmallIcon(io.narl.protonstream.R.drawable.ic_launcher_foreground)
-            .setContentTitle("Making episode available offline")
+            .setContentTitle(label)
-            .setProgress(100, progress, progress == 0)
+            .setContentText(if (progress == null) "Waiting to download" else "$progress %")
+            .setProgress(100, progress ?: 0, progress == null || progress == 0)
             .setOngoing(true)
+            .setOnlyAlertOnce(true)
+            .setGroup(GROUP)
             .build()
         return ForegroundInfo(
             stableNotificationId(id),
@@ -97,6 +161,36 @@ class OfflineDownloadWorker(
         )
     }
 
+    /**
+     * The one line the group folds into — "Downloading 12 episodes" — or none
+     * once nothing is left to download. Posted as each worker starts and
+     * ends rather than on progress, which each episode's own line carries.
+     */
+    private fun postSummary(store: DownloadStateStore) {
+        val manager = applicationContext.getSystemService(NotificationManager::class.java)
+        val left = store.records().count {
+            it.status == RetainedDownload.STATUS_QUEUED || it.status == RetainedDownload.STATUS_RUNNING
+        }
+        if (left == 0) {
+            manager.cancel(SUMMARY_ID)
+            return
+        }
+        val allowed = Build.VERSION.SDK_INT < Build.VERSION_CODES.TIRAMISU ||
+            ContextCompat.checkSelfPermission(applicationContext, Manifest.permission.POST_NOTIFICATIONS) ==
+            PackageManager.PERMISSION_GRANTED
+        if (!allowed) return
+        manager.notify(
+            SUMMARY_ID,
+            NotificationCompat.Builder(applicationContext, CHANNEL_ID)
+                .setSmallIcon(io.narl.protonstream.R.drawable.ic_launcher_foreground)
+                .setContentTitle(if (left == 1) "Downloading 1 episode" else "Downloading $left episodes")
+                .setOnlyAlertOnce(true)
+                .setGroup(GROUP)
+                .setGroupSummary(true)
+                .build(),
+        )
+    }
+
     private fun error(message: String) = Data.Builder().putString(KEY_ERROR, message).build()
 
     companion object {
@@ -109,8 +203,45 @@ class OfflineDownloadWorker(
         const val KEY_TOTAL = "total"
         private const val MAX_RETRIES = 3
         private const val CHANNEL_ID = "offline-downloads"
+        private const val GROUP = "offline-downloads"
+
+        /** Below [stableNotificationId]'s range, so no episode's line replaces it. */
+        internal const val SUMMARY_ID = 1
+
+        /** Shortest gap between two identical-looking progress reports. */
+        private const val PROGRESS_INTERVAL_MS = 1_000L
+    }
+}
+
+/**
+ * Bytes per second over roughly the last few seconds.
+ *
+ * Progress arrives once per 4 MiB block, so on a slow link the bar moves in
+ * steps seconds apart; a rate beside it is what tells a slow download from a
+ * stuck one. Smoothed, because one block that took a little longer than the
+ * last would otherwise halve the figure for a moment.
+ */
+internal class TransferRate {
+    private var lastBytes = -1L
+    private var lastAt = 0L
+    private var smoothed = 0.0
+
+    /** Record [bytes] transferred at [now] (milliseconds) and return the rate. */
+    fun sample(bytes: Long, now: Long): Long {
+        if (lastBytes < 0 || bytes < lastBytes) {
+            lastBytes = bytes
+            lastAt = now
+            return smoothed.toLong()
+        }
+        val elapsed = now - lastAt
+        if (elapsed <= 0) return smoothed.toLong()
+        val instant = (bytes - lastBytes) * 1000.0 / elapsed
+        smoothed = if (smoothed > 0.0) 0.7 * smoothed + 0.3 * instant else instant
+        lastBytes = bytes
+        lastAt = now
+        return smoothed.toLong()
     }
 }
 
 internal fun stableNotificationId(workId: UUID): Int =
-    (workId.hashCode() and Int.MAX_VALUE).coerceAtLeast(1)
+    (workId.hashCode() and Int.MAX_VALUE).coerceAtLeast(OfflineDownloadWorker.SUMMARY_ID + 1)

android/app/src/main/java/io/narl/protonstream/native/KeystoreSecretStore.kt

@@ -2,6 +2,7 @@ package io.narl.protonstream.native
 
 import android.content.Context
 import android.security.keystore.KeyGenParameterSpec
+import android.security.keystore.KeyPermanentlyInvalidatedException
 import android.security.keystore.KeyProperties
 import android.util.Base64
 import java.security.KeyStore
@@ -10,22 +11,44 @@ import javax.crypto.KeyGenerator
 import javax.crypto.SecretKey
 import javax.crypto.spec.GCMParameterSpec
 import uniffi.pstr_android.AndroidSecretStore
+import uniffi.pstr_android.BridgeException
 
-/** Encrypts share fragments and passwords before they reach app preferences. */
+/**
+ * Encrypts share fragments and passwords before they reach app preferences.
+ *
+ * Every failure here leaves as a [BridgeException]. Raw Java exceptions crossing
+ * the FFI have no mapping on the Rust side, and an unmapped callback exception
+ * is a panic on whichever thread was calling — including a tokio worker holding
+ * a download. What the caller does about it is a separate question; being told
+ * at all is this class's part.
+ */
 class KeystoreSecretStore(context: Context) : AndroidSecretStore {
     private val preferences = context.getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE)
     private val keyStore = KeyStore.getInstance("AndroidKeyStore").apply { load(null) }
 
-    override fun set(key: String, value: String) {
+    override fun set(key: String, value: String) = bridging("store credential") {
-        val cipher = Cipher.getInstance(TRANSFORMATION)
+        val payload = try {
-        cipher.init(Cipher.ENCRYPT_MODE, encryptionKey())
+            seal(value)
-        val encrypted = cipher.doFinal(value.toByteArray(Charsets.UTF_8))
+        } catch (invalidated: KeyPermanentlyInvalidatedException) {
-        val payload = cipher.iv + encrypted
+            // A lockscreen change or a device restore retires the key. Nothing
+            // it sealed can be read again — and nothing new can be sealed with
+            // it either, so re-entering a link would fail here rather than
+            // restoring access. Everything the old key held is already lost, so
+            // replacing it costs nothing that is not gone.
+            keyStore.deleteEntry(KEY_ALIAS)
+            seal(value)
+        }
         check(preferences.edit().putString(key, Base64.encodeToString(payload, Base64.NO_WRAP)).commit())
     }
 
-    override fun get(key: String): String? {
+    private fun seal(value: String): ByteArray {
-        val encoded = preferences.getString(key, null) ?: return null
+        val cipher = Cipher.getInstance(TRANSFORMATION)
+        cipher.init(Cipher.ENCRYPT_MODE, encryptionKey())
+        return cipher.iv + cipher.doFinal(value.toByteArray(Charsets.UTF_8))
+    }
+
+    override fun get(key: String): String? = bridging("read credential") {
+        val encoded = preferences.getString(key, null) ?: return@bridging null
         val payload = Base64.decode(encoded, Base64.NO_WRAP)
         require(payload.size > IV_SIZE) { "Invalid encrypted credential" }
         val cipher = Cipher.getInstance(TRANSFORMATION)
@@ -34,13 +57,23 @@ class KeystoreSecretStore(context: Context) : AndroidSecretStore {
             encryptionKey(),
             GCMParameterSpec(TAG_BITS, payload.copyOfRange(0, IV_SIZE)),
         )
-        return cipher.doFinal(payload.copyOfRange(IV_SIZE, payload.size)).toString(Charsets.UTF_8)
+        cipher.doFinal(payload.copyOfRange(IV_SIZE, payload.size)).toString(Charsets.UTF_8)
     }
 
-    override fun delete(key: String) {
+    override fun delete(key: String) = bridging("delete credential") {
         check(preferences.edit().remove(key).commit())
     }
 
+    private fun <T> bridging(action: String, block: () -> T): T = try {
+        block()
+    } catch (error: BridgeException) {
+        throw error
+    } catch (error: Exception) {
+        // The message, never the stack trace: this reaches a snackbar, and the
+        // trace is both unreadable there and a description of app internals.
+        throw BridgeException.Failure("Could not $action: ${error.message ?: error::class.java.simpleName}")
+    }
+
     private fun encryptionKey(): SecretKey {
         (keyStore.getKey(KEY_ALIAS, null) as? SecretKey)?.let { return it }
         return KeyGenerator.getInstance(KeyProperties.KEY_ALGORITHM_AES, "AndroidKeyStore").run {

android/app/src/main/java/io/narl/protonstream/native/NativeRuntime.kt

@@ -1,25 +1,36 @@
 package io.narl.protonstream.native
 
 import android.content.Context
+import io.narl.protonstream.settings.SettingsStore
 import java.io.File
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
 import uniffi.pstr_android.AndroidEngine
 import uniffi.pstr_android.AndroidPaths
+import uniffi.pstr_android.PaletteRecord
 
 /** Process-wide owner of the Rust engine; records and decrypted media remain app-private. */
 object NativeRuntime {
     private lateinit var appContext: Context
     @Volatile private var instance: AndroidEngine? = null
 
+    /**
+     * Whether Android's certificate verifier came up.
+     *
+     * False means every HTTPS request will fail validation, which otherwise
+     * surfaces much later as an unexplained certificate error against a share.
+     */
+    @Volatile var tlsReady: Boolean = false
+        private set
+
     fun initialize(context: Context) {
         System.loadLibrary("pstr_android")
-        initTls(context)
+        tlsReady = initTls(context)
         appContext = context.applicationContext
     }
 
     /** Initializes Android's certificate verifier before Proton networking. */
-    private external fun initTls(context: Context)
+    private external fun initTls(context: Context): Boolean
 
     suspend fun engine(): AndroidEngine = withContext(Dispatchers.IO) {
         instance ?: synchronized(this@NativeRuntime) {
@@ -27,14 +38,28 @@ object NativeRuntime {
         }
     }
 
-    private fun createEngine(): AndroidEngine {
+    /**
+     * The stored palette, without building the engine.
+     *
+     * Callable from the main thread, and meant to be: it is the only palette
+     * read early enough to decide what the first frame is painted in, and
+     * [engine] is not — that opens SQLite, spins a Tokio runtime and unlocks a
+     * Keystore key. This reads one small JSON file and resolves it.
+     */
+    fun storedPalette(): PaletteRecord = uniffi.pstr_android.storedPalette(paths())
+
+    private fun paths(): AndroidPaths {
         check(::appContext.isInitialized) { "NativeRuntime is not initialized" }
         val config = File(appContext.noBackupFilesDir, "config")
         val data = File(appContext.filesDir, "data")
         val cache = File(appContext.cacheDir, "stream")
-        return AndroidEngine(
+        return AndroidPaths(config.absolutePath, data.absolutePath, cache.absolutePath)
-            AndroidPaths(config.absolutePath, data.absolutePath, cache.absolutePath),
-            KeystoreSecretStore(appContext),
-        )
     }
+
+    private fun createEngine(): AndroidEngine =
+        AndroidEngine(paths(), KeystoreSecretStore(appContext)).apply {
+            // The budget is Android's setting, so the engine starts on the
+            // default and is told the chosen one before anything streams.
+            setStreamCacheBudget(SettingsStore.gibToBytes(SettingsStore(appContext).cacheBudgetGib))
+        }
 }

android/app/src/main/java/io/narl/protonstream/playback/LibmpvPlayerSurface.kt

@@ -1,343 +0,0 @@
-package io.narl.protonstream.playback
-
-import android.view.Surface
-import android.view.SurfaceHolder
-import android.view.SurfaceView
-import androidx.compose.foundation.background
-import androidx.compose.foundation.layout.Box
-import androidx.compose.foundation.layout.fillMaxSize
-import androidx.compose.foundation.layout.fillMaxWidth
-import androidx.compose.foundation.layout.padding
-import androidx.compose.foundation.layout.Row
-import androidx.compose.foundation.layout.Column
-import androidx.compose.foundation.layout.Arrangement
-import androidx.compose.foundation.layout.heightIn
-import androidx.compose.foundation.lazy.LazyColumn
-import androidx.compose.foundation.lazy.items
-import androidx.compose.animation.AnimatedVisibility
-import androidx.compose.animation.fadeIn
-import androidx.compose.animation.fadeOut
-import androidx.compose.foundation.clickable
-import androidx.compose.material3.AlertDialog
-import androidx.compose.material3.Button
-import androidx.compose.material3.OutlinedButton
-import androidx.compose.material3.Slider
-import androidx.compose.material3.MaterialTheme
-import androidx.compose.material3.Text
-import androidx.compose.material3.Icon
-import androidx.compose.material3.IconButton
-import androidx.compose.material.icons.Icons
-import androidx.compose.material.icons.filled.PlayArrow
-import androidx.compose.material.icons.filled.Pause
-import androidx.compose.material.icons.filled.Fullscreen
-import androidx.compose.material.icons.filled.FullscreenExit
-import androidx.compose.material.icons.filled.VolumeUp
-import androidx.compose.material.icons.filled.VolumeOff
-import androidx.compose.material.icons.filled.Subtitles
-import androidx.compose.material.icons.filled.Audiotrack
-import androidx.compose.runtime.Composable
-import androidx.compose.runtime.DisposableEffect
-import androidx.compose.runtime.LaunchedEffect
-import androidx.compose.runtime.remember
-import androidx.compose.runtime.rememberCoroutineScope
-import androidx.compose.runtime.collectAsState
-import androidx.compose.runtime.getValue
-import androidx.compose.runtime.mutableStateOf
-import androidx.compose.runtime.setValue
-import androidx.compose.ui.Alignment
-import androidx.compose.ui.Modifier
-import androidx.compose.ui.graphics.Color
-import androidx.compose.ui.unit.dp
-import androidx.compose.ui.viewinterop.AndroidView
-import io.narl.protonstream.native.NativeRuntime
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.delay
-import kotlinx.coroutines.launch
-import kotlinx.coroutines.withContext
-import uniffi.pstr_android.AndroidEngine
-import uniffi.pstr_android.AndroidStream
-import uniffi.pstr_android.EpisodeRecord
-import kotlin.math.roundToInt
-
-/** Exact seekable stream contract a bundled libmpv JNI adapter must consume. */
-class RustStreamSession(
-    private val episode: EpisodeRecord,
-) {
-    private var engine: AndroidEngine? = null
-    private var stream: AndroidStream? = null
-    private var handle: ULong? = null
-    private var streamSize: ULong? = null
-
-    suspend fun open(): RustStreamSession = withContext(Dispatchers.IO) {
-        val openedEngine = NativeRuntime.engine()
-        engine = openedEngine
-        stream = openedEngine.openStream(episode.shareId, episode.volumeId, episode.linkId).also {
-            streamSize = it.size()
-            handle = it.nativeHandle()
-        }
-        this@RustStreamSession
-    }
-
-    fun nativeHandle(): ULong = checkNotNull(handle) { "stream is not published" }
-
-    fun size(): ULong = checkNotNull(streamSize) { "stream is not open" }
-
-    fun releaseNative(host: LibmpvHost) {
-        handle?.let(host::releaseNativeStream)
-        handle = null
-        streamSize = null
-        stream = null
-    }
-
-    /** The native player now owns the published token until stop/end/close. */
-    fun transferToPlayer() {
-        handle = null
-        streamSize = null
-        stream = null
-    }
-
-    suspend fun closeEngine() = withContext(Dispatchers.IO) {
-        engine?.releaseStream(episode.shareId, episode.volumeId, episode.linkId)
-        engine = null
-    }
-}
-
-/** Implement only in the variant that bundles a pinned libmpv native artifact. */
-interface LibmpvHost {
-    fun attachSurface(surface: Surface)
-    fun detachSurface()
-    /** Consumes the opaque handle through pstr_android_stream_{read,size}. */
-    suspend fun play(
-        nativeHandle: ULong,
-        size: ULong,
-        startPosition: Double = 0.0,
-        audioLanguage: String? = null,
-        subtitleLanguage: String? = null,
-        subtitles: Boolean = true,
-    )
-    /** Calls pstr_android_stream_release exactly once for a published handle. */
-    fun releaseNativeStream(nativeHandle: ULong)
-}
-
-private data class PlaybackStartup(
-    val nativeHandle: ULong,
-    val size: ULong,
-    val startPosition: Double,
-    val audioLanguage: String?,
-    val subtitleLanguage: String?,
-    val subtitles: Boolean,
-)
-
-@Composable
-fun LibmpvPlayerSurface(
-    titleKey: String,
-    episode: EpisodeRecord,
-    host: LibmpvHost? = null,
-    isFullscreen: Boolean = false,
-    onToggleFullscreen: () -> Unit = {}
-) {
-    if (host == null) {
-        Box(Modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
-            Text("Playback is unavailable: this build does not include libmpv.", color = Color.White)
-        }
-        return
-    }
-
-    val scope = rememberCoroutineScope()
-    var playbackError by remember(sessionKey(episode)) { mutableStateOf<String?>(null) }
-    val session = remember(episode.shareId, episode.linkId) {
-        RustStreamSession(episode)
-    }
-    LaunchedEffect(session, host) {
-        runCatching {
-            val startup = withContext(Dispatchers.IO) {
-                session.open()
-                val engine = NativeRuntime.engine()
-                val preferences = engine.titleTrackPreferences(titleKey)
-                val watch = engine.watchState(episode.shareId, episode.linkId)
-                PlaybackStartup(
-                    nativeHandle = session.nativeHandle(),
-                    size = session.size(),
-                    startPosition = watch?.positionSecs ?: 0.0,
-                    audioLanguage = preferences.audioLanguage,
-                    subtitleLanguage = preferences.subtitleLanguage,
-                    subtitles = preferences.subtitles,
-                )
-            }
-            host.play(
-                startup.nativeHandle, startup.size, startup.startPosition,
-                startup.audioLanguage, startup.subtitleLanguage, startup.subtitles,
-            )
-            session.transferToPlayer()
-        }.onFailure { playbackError = it.message ?: "Playback failed" }
-    }
-    DisposableEffect(session, host) {
-        onDispose {
-            host.detachSurface()
-            session.releaseNative(host)
-            scope.launch { session.closeEngine() }
-        }
-    }
-    
-    var showControls by remember { mutableStateOf(true) }
-    LaunchedEffect(showControls) {
-        if (showControls) {
-            delay(4000)
-            showControls = false
-        }
-    }
-
-    Box(Modifier.fillMaxSize().clickable(
-        interactionSource = remember { androidx.compose.foundation.interaction.MutableInteractionSource() },
-        indication = null,
-        onClick = { showControls = !showControls }
-    )) {
-        AndroidView(
-            modifier = Modifier.fillMaxSize(),
-            factory = { context ->
-                SurfaceView(context).apply {
-                    holder.addCallback(object : SurfaceHolder.Callback {
-                        override fun surfaceCreated(holder: SurfaceHolder) = host.attachSurface(holder.surface)
-                        override fun surfaceChanged(holder: SurfaceHolder, format: Int, width: Int, height: Int) = host.attachSurface(holder.surface)
-                        override fun surfaceDestroyed(holder: SurfaceHolder) = host.detachSurface()
-                    })
-                }
-            },
-        )
-        AnimatedVisibility(
-            visible = showControls,
-            modifier = Modifier.align(Alignment.BottomCenter),
-            enter = fadeIn(),
-            exit = fadeOut()
-        ) {
-            if (host is NativeMpvHost) PlayerControls(
-                titleKey,
-                episode,
-                host,
-                isFullscreen,
-                onToggleFullscreen
-            )
-        }
-        playbackError?.let { message ->
-            Text(message, color = Color.White, modifier = Modifier.align(Alignment.Center).background(Color.Black.copy(alpha = 0.8f)).padding(16.dp))
-        }
-    }
-}
-
-private fun sessionKey(episode: EpisodeRecord) = "${episode.shareId}:${episode.linkId}"
-
-@Composable
-private fun PlayerControls(
-    titleKey: String,
-    episode: EpisodeRecord,
-    host: NativeMpvHost,
-    isFullscreen: Boolean,
-    onToggleFullscreen: () -> Unit,
-    modifier: Modifier = Modifier
-) {
-    val state by host.state.collectAsState()
-    val tracks by host.tracks.collectAsState()
-    val scope = rememberCoroutineScope()
-    var choosing by remember { mutableStateOf<String?>(null) }
-    LaunchedEffect(state.position.roundToInt() / 5) {
-        if (state.duration > 0.0) withContext(Dispatchers.IO) {
-            NativeRuntime.engine().saveWatchState(
-                episode.shareId, episode.linkId, state.position.coerceAtMost(state.duration), state.duration,
-                state.ended || state.position >= state.duration * 0.9,
-            )
-        }
-    }
-    Column(modifier.fillMaxWidth().background(Color.Black.copy(alpha = 0.68f)).padding(12.dp)) {
-        Slider(
-            value = state.position.toFloat().coerceIn(0f, state.duration.toFloat().coerceAtLeast(1f)),
-            onValueChange = { host.seek(it.toDouble()) },
-            valueRange = 0f..state.duration.toFloat().coerceAtLeast(1f),
-        )
-        Row(Modifier.fillMaxWidth(), horizontalArrangement = Arrangement.SpaceBetween, verticalAlignment = Alignment.CenterVertically) {
-            IconButton(onClick = { host.setPaused(!state.paused) }) { 
-                Icon(if (state.paused) Icons.Default.PlayArrow else Icons.Default.Pause, contentDescription = "Play/Pause", tint = Color.White) 
-            }
-            Text("${formatTime(state.position)} / ${formatTime(state.duration)}", color = Color.White)
-            Row(horizontalArrangement = Arrangement.spacedBy(8.dp)) {
-                IconButton(onClick = { host.setMuted(!state.muted) }) { 
-                    Icon(if (state.muted) Icons.Default.VolumeOff else Icons.Default.VolumeUp, contentDescription = "Mute", tint = Color.White) 
-                }
-                IconButton(onClick = onToggleFullscreen) { 
-                    Icon(if (isFullscreen) Icons.Default.FullscreenExit else Icons.Default.Fullscreen, contentDescription = "Fullscreen", tint = Color.White) 
-                }
-            }
-        }
-        Row(horizontalArrangement = Arrangement.spacedBy(8.dp), verticalAlignment = Alignment.CenterVertically) {
-            IconButton(onClick = { choosing = "audio" }) {
-                Icon(Icons.Default.Audiotrack, contentDescription = "Audio", tint = Color.White)
-            }
-            IconButton(onClick = { choosing = "sub" }) {
-                Icon(Icons.Default.Subtitles, contentDescription = "Subtitles", tint = Color.White)
-            }
-            Text(
-                "Audio: ${tracks.firstOrNull { it.type == "audio" && it.selected }?.label ?: "default"}  •  " +
-                "Subtitles: ${tracks.firstOrNull { it.type == "sub" && it.selected }?.label ?: "off"}",
-                color = Color.White,
-                style = MaterialTheme.typography.bodySmall
-            )
-        }
-    }
-    choosing?.let { type ->
-        TrackChooser(
-            type = type,
-            tracks = tracks.filter { it.type == type },
-            onDismiss = { choosing = null },
-            onSelect = { selected ->
-                host.selectTrack(selected)
-                choosing = null
-                scope.launch(Dispatchers.IO) {
-                    val engine = NativeRuntime.engine()
-                    val old = engine.titleTrackPreferences(titleKey)
-                    engine.setTitleTrackPreferences(
-                        titleKey,
-                        if (type == "audio") old.copy(audioLanguage = selected?.language?.takeIf(String::isNotBlank))
-                        else old.copy(
-                            subtitleLanguage = selected?.language?.takeIf(String::isNotBlank),
-                            subtitles = selected != null,
-                        ),
-                    )
-                }
-            },
-        )
-    }
-}
-
-@Composable
-private fun TrackChooser(
-    type: String,
-    tracks: List<MpvTrack>,
-    onDismiss: () -> Unit,
-    onSelect: (MpvTrack?) -> Unit,
-) {
-    AlertDialog(
-        onDismissRequest = onDismiss,
-        title = { Text(if (type == "audio") "Audio track" else "Subtitle track") },
-        text = {
-            LazyColumn(Modifier.fillMaxWidth().heightIn(max = 420.dp)) {
-                if (type == "sub") {
-                    item {
-                        OutlinedButton(onClick = { onSelect(null) }, Modifier.fillMaxWidth()) {
-                            Text(if (tracks.none(MpvTrack::selected)) "✓  Off" else "Off")
-                        }
-                    }
-                }
-                items(tracks, key = MpvTrack::id) { track ->
-                    OutlinedButton(onClick = { onSelect(track) }, Modifier.fillMaxWidth()) {
-                        Text(if (track.selected) "✓  ${track.label}" else track.label)
-                    }
-                }
-            }
-        },
-        confirmButton = { Button(onClick = onDismiss) { Text("Close") } },
-    )
-}
-
-private fun formatTime(seconds: Double): String {
-    val total = seconds.coerceAtLeast(0.0).roundToInt()
-    return "%d:%02d".format(total / 60, total % 60)
-}

android/app/src/main/java/io/narl/protonstream/playback/NativeMpvHost.kt

@@ -1,6 +1,7 @@
 package io.narl.protonstream.playback
 
 import android.view.Surface
+import io.narl.protonstream.ui.ThumbnailSource
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.Job
@@ -16,6 +17,34 @@ import kotlinx.coroutines.withContext
 import org.json.JSONArray
 import java.util.concurrent.locks.ReentrantLock
 import kotlin.concurrent.withLock
+import uniffi.pstr_android.ChapterPlan
+import uniffi.pstr_android.ChapterRecord
+import uniffi.pstr_android.SubtitleFilesRecord
+import uniffi.pstr_android.SubtitleTrackRecord
+import uniffi.pstr_android.chapterPlan
+import uniffi.pstr_android.fullSubtitlesInstead
+
+/**
+ * Why the open file ended, mirroring `pstr_player::EndReason` so both clients
+ * agree on what "finished" means.
+ *
+ * Only [Eof] is an episode watched to the end. Treating the others as one — a
+ * stop, a shutdown, a failed demux — is what marks an episode that never played
+ * as watched and autoplays past it.
+ */
+enum class EndReason {
+    None,
+    Eof,
+    Stopped,
+    Quit,
+    Failed,
+    Other,
+    ;
+
+    companion object {
+        fun of(value: Double): EndReason = entries.getOrElse(value.toInt()) { Other }
+    }
+}
 
 data class MpvPlaybackState(
     val position: Double = 0.0,
@@ -24,6 +53,55 @@ data class MpvPlaybackState(
     val paused: Boolean = true,
     val muted: Boolean = false,
     val ended: Boolean = false,
+    /** Meaningful only while [ended]; [EndReason.None] otherwise. */
+    val endReason: EndReason = EndReason.None,
+    /**
+     * Which episode this reading belongs to, or null before the first poll of a
+     * newly loaded file. Everything that *writes* per-episode state — resume
+     * position above all — must check this: one host serves every episode, and
+     * a reading attributed to the wrong one resumes the next episode where the
+     * last one stopped.
+     */
+    val media: String? = null,
+    /** The picture's display size, or zero until mpv has decoded enough to know. */
+    val videoWidth: Double = 0.0,
+    val videoHeight: Double = 0.0,
+    /**
+     * mpv has run out of buffered data and stopped to refill.
+     *
+     * Not the same as [paused], which is the viewer's doing. A frozen picture
+     * that nothing explains is indistinguishable from a hung app, which is what
+     * a network-backed stream looked like before this existed.
+     */
+    val buffering: Boolean = false,
+    /** How full the demuxer cache is while [buffering], 0–100. */
+    val cachePercent: Double = 0.0,
+    /** A seek has been issued but playback has not resumed at the new position. */
+    val seeking: Boolean = false,
+    /** How far the demuxer has read ahead, in seconds into the file. */
+    val cachedUntil: Double = 0.0,
+) {
+    /** Whether the picture is stopped for a reason the viewer did not choose. */
+    val stalled: Boolean get() = (buffering || seeking) && !paused && !ended
+}
+
+/**
+ * What is on screen, for the surfaces that are not the player.
+ *
+ * The media session and its notification have to name the episode, and
+ * neither can reach the composition that knows it. The player publishes this
+ * once per episode and they read it.
+ */
+data class NowPlaying(
+    val media: String,
+    val title: String,
+    val show: String?,
+    val detail: String?,
+    val artworkUrl: String?,
+    /** The file to pull a Proton thumbnail from when the provider has no poster. */
+    val artworkFile: ThumbnailSource?,
+    val hasPrevious: Boolean,
+    val hasNext: Boolean,
 )
 
 data class MpvTrack(
@@ -32,27 +110,73 @@ data class MpvTrack(
     val language: String,
     val title: String,
     val selected: Boolean,
+    /** The container marks it as the default choice. */
+    val isDefault: Boolean = false,
+    /** The container marks it as forced: on-screen text only, by convention. */
+    val forced: Boolean = false,
 ) {
     val label: String get() = listOf(language, title).filter(String::isNotBlank)
         .joinToString(" — ").ifBlank { "${type.replaceFirstChar(Char::uppercase)} $id" }
 }
 
 /** Process-local owner of the libmpv core. PlaybackService owns its lifetime. */
-class NativeMpvHost : LibmpvHost, AutoCloseable {
+class NativeMpvHost private constructor(private val nativeHandle: Long) : LibmpvHost, AutoCloseable {
-    private val nativeHandle = nativeCreate().also { check(it != 0L) { "libmpv initialization failed" } }
     private val lifecycle = ReentrantLock()
     @Volatile private var closed = false
     private val scope = CoroutineScope(SupervisorJob() + Dispatchers.Main.immediate)
     private val mutableState = MutableStateFlow(MpvPlaybackState())
     private val mutableTracks = MutableStateFlow(emptyList<MpvTrack>())
+    private val mutableChapters = MutableStateFlow(ChapterPlan(emptyList(), null))
+    private val mutableNowPlaying = MutableStateFlow<NowPlaying?>(null)
+    private val mutableAdvancing = MutableStateFlow(false)
+    private val mutableProblem = MutableStateFlow<String?>(null)
     private var poller: Job? = null
-    private var currentStreamHandle: Long? = null
+    /** The episode key and load generation the native player currently holds. */
+    @Volatile private var currentMedia: String? = null
+    @Volatile private var currentGeneration: Double = -1.0
+    @Volatile private var plannedFor: Pair<Double, Long>? = null
+    /** The load generation whose subtitle pick has been looked at. */
+    @Volatile private var subtitlesCheckedFor: Double = -1.0
     var onPlaybackStarted: (() -> Unit)? = null
     var onStateChanged: ((MpvPlaybackState) -> Unit)? = null
     var onExplicitStop: (() -> Unit)? = null
+    /**
+     * Where a transport outside the player sends previous/next.
+     *
+     * The player owns which episode is open, so the notification and the lock
+     * screen cannot walk the playlist themselves. Both
+     * run on the main thread, which is where the player's state lives.
+     */
+    var onSkipPrevious: (() -> Unit)? = null
+    var onSkipNext: (() -> Unit)? = null
 
     val state: StateFlow<MpvPlaybackState> = mutableState.asStateFlow()
     val tracks: StateFlow<List<MpvTrack>> = mutableTracks.asStateFlow()
+    /** The open file's chapters, already resolved into openings and endings. */
+    val chapters: StateFlow<ChapterPlan> = mutableChapters.asStateFlow()
+    /** The episode the player has open, for every surface that has to name it. */
+    val nowPlaying: StateFlow<NowPlaying?> = mutableNowPlaying.asStateFlow()
+    /**
+     * True while the player is between episodes.
+     *
+     * The end of one episode and the start of the next are separated by a
+     * network round trip — opening the next revision's stream. The foreground
+     * service must not retire in that gap: with no foreground state left, the
+     * `startForeground` on the other side is a background start, which API 31+
+     * refuses outright.
+     */
+    val advancing: StateFlow<Boolean> = mutableAdvancing.asStateFlow()
+    /**
+     * What mpv last complained about, until the viewer dismisses it.
+     *
+     * Errors mpv reports are about the *file* — an unreadable header, a codec it
+     * has no decoder for — and reach nothing else: the play call has already
+     * returned successfully by the time they happen.
+     */
+    val problem: StateFlow<String?> = mutableProblem.asStateFlow()
+
+    /** Dismiss the current [problem]. */
+    fun clearProblem() { mutableProblem.value = null }
     val hasActivePlayback: Boolean get() = mutableState.value.duration > 0.0 && !mutableState.value.ended
 
     override fun attachSurface(surface: Surface) {
@@ -64,84 +188,242 @@ class NativeMpvHost : LibmpvHost, AutoCloseable {
     }
 
     override suspend fun play(
+        media: String,
         nativeHandle: ULong,
         size: ULong,
         startPosition: Double,
         audioLanguage: String?,
         subtitleLanguage: String?,
         subtitles: Boolean,
+        hardwareDecoding: Boolean,
     ) {
         check(size > 0uL) { "Cannot play an empty stream" }
-        withContext(Dispatchers.IO) {
+        try {
-            val loaded = withOpenHandle {
+            withContext(Dispatchers.IO) {
-                nativeLoad(it, nativeHandle.toLong(), startPosition, audioLanguage, subtitleLanguage, subtitles).also { loaded ->
+                val loaded = withOpenHandle {
-                    if (loaded) {
+                    nativeLoad(
-                        currentStreamHandle?.let(::pstrAndroidStreamRelease)
+                        it, nativeHandle.toLong(), startPosition, audioLanguage, subtitleLanguage, subtitles,
-                        currentStreamHandle = nativeHandle.toLong()
+                        hardwareDecoding,
+                    ).also { loaded ->
+                        if (loaded) {
+                            // The outgoing stream is released by mpv closing it,
+                            // not from here: `loadfile` is asynchronous and its
+                            // demuxer may still be reading. `stream_close` in
+                            // `pstr_mpv.cpp` owns that release.
+                            //
+                            // The outgoing file's readings describe an episode
+                            // that is no longer open. Retire them here as well
+                            // as natively, so nothing observes them even once.
+                            currentMedia = media
+                            currentGeneration = withOpenHandle(::nativeState)?.generation() ?: -1.0
+                            mutableState.value = MpvPlaybackState(
+                                position = startPosition,
+                                volume = mutableState.value.volume,
+                                muted = mutableState.value.muted,
+                                media = media,
+                            )
+                            mutableProblem.value = null
+                            mutableTracks.value = emptyList()
+                            mutableChapters.value = ChapterPlan(emptyList(), null)
+                            plannedFor = null
+                        }
                     }
+                } ?: false
+                check(loaded) {
+                    "libmpv rejected the stream or no video surface was available"
                 }
-            } ?: false
-            check(loaded) {
-                "libmpv rejected the stream or no video surface was available"
             }
-        }
+            withOpenHandle {
-        withOpenHandle {
+                onPlaybackStarted?.invoke()
-            onPlaybackStarted?.invoke()
+                startPolling()
-            startPolling()
+            }
+        } finally {
+            // Whether the next episode arrived or failed to, the gap the
+            // foreground service was holding open is over.
+            mutableAdvancing.value = false
         }
     }
 
-    fun setPaused(paused: Boolean) { withOpenHandle { nativePause(it, paused) } }
+    /**
+     * Declare that the player is walking to another episode.
+     *
+     * Called before the stream for the next one is opened, and cleared when
+     * [play] returns either way — the window this covers is the one in which
+     * nothing is loaded and the service would otherwise conclude playback is
+     * finished.
+     */
+    fun beginTransition() { mutableAdvancing.value = true }
+
+    /** Names the open episode for the media session and its notification. */
+    fun publish(playing: NowPlaying?) { mutableNowPlaying.value = playing }
+
+    fun setPaused(paused: Boolean) {
+        // The native side writes the flag through, so every transport can flip
+        // now instead of on the next poll a quarter second from here.
+        val next = withOpenHandle {
+            nativePause(it, paused)
+            mutableState.value.copy(paused = paused).also { state -> mutableState.value = state }
+        } ?: return
+        onStateChanged?.invoke(next)
+    }
+
     fun seek(position: Double) { withOpenHandle { nativeSeek(it, position) } }
     fun setVolume(volume: Double) { withOpenHandle { nativeVolume(it, volume) } }
     fun setMuted(muted: Boolean) { withOpenHandle { nativeMute(it, muted) } }
+
+    /** Playback rate, 1.0 being the file's own. Clamped native-side. */
+    fun setSpeed(speed: Double) { withOpenHandle { nativeSpeed(it, speed) } }
     fun selectTrack(track: MpvTrack?) {
         val audio = track?.type == "audio"
         withOpenHandle { nativeSelectTrack(it, audio, track?.id ?: -1) }
         refreshTracks()
     }
 
-    /** Explicit user stop: stop media, release its stream, and retire the foreground service. */
+    /**
+     * Explicit user stop: stop media and retire the foreground service.
+     *
+     * The stream behind the open file is released by mpv closing it, which
+     * `stop` causes; releasing it from here would race that close.
+     */
     fun stop() {
         val callback = withOpenHandle {
             nativeStop(it)
-            currentStreamHandle?.let(::pstrAndroidStreamRelease)
+            // Nothing loaded means nothing to attribute a reading to: a save
-            currentStreamHandle = null
+            // issued after this must not land on the episode just stopped.
+            currentMedia = null
+            mutableAdvancing.value = false
+            mutableChapters.value = ChapterPlan(emptyList(), null)
+            mutableNowPlaying.value = null
             onExplicitStop
         }
         callback?.invoke()
     }
 
-    internal fun releaseEndedStream() {
-        withOpenHandle { currentStreamHandle?.let(::pstrAndroidStreamRelease); currentStreamHandle = null }
-    }
-
     override fun releaseNativeStream(nativeHandle: ULong) = pstrAndroidStreamRelease(nativeHandle.toLong())
 
+    /**
+     * Hand mpv the subtitle files beside [media], the episode [play] loaded.
+     *
+     * Native code holds them until mpv has the file loaded, since an external
+     * track belongs to the file open at the time, and releases them instead
+     * if another episode has been loaded since. [SubtitleFilesRecord.preferred]
+     * is turned on only when the file has no subtitle of its own playing;
+     * pass [subtitles] false to turn none on.
+     */
+    fun addSubtitles(media: String, files: SubtitleFilesRecord, subtitles: Boolean) {
+        val generation = currentGeneration.toLong()
+        val added = withOpenHandle { handle ->
+            files.files.forEachIndexed { index, file ->
+                if (currentMedia == media) {
+                    val select = subtitles && files.preferred == index.toUInt()
+                    nativeAddSubtitle(handle, generation, file.handle.toLong(), file.title, file.language, select)
+                } else {
+                    pstrAndroidStreamRelease(file.handle.toLong())
+                }
+            }
+        }
+        if (added == null) files.files.forEach { pstrAndroidStreamRelease(it.handle.toLong()) }
+    }
+
     private fun startPolling() {
         if (poller?.isActive == true) return
-        poller = scope.launch {
+        // Off the main thread deliberately: `nativeState` and `nativeTracks`
+        // are synchronous `mpv_get_property` calls — five per track for the
+        // latter — that contend on the core lock the demuxer holds during a
+        // fetch. A poll that blocks there blocks the UI thread with it.
+        poller = scope.launch(Dispatchers.Default) {
             var tick = 0
             while (isActive) {
                 val values = withOpenHandle(::nativeState) ?: break
-                if (values.size >= 6) {
+                if (values.size >= FIELDS) {
-                    val next = MpvPlaybackState(values[0], values[1], values[2], values[3] != 0.0, values[4] != 0.0, values[5] != 0.0)
+                    val next = MpvPlaybackState(
+                        values[0], values[1], values[2],
+                        values[3] != 0.0, values[4] != 0.0, values[5] != 0.0,
+                        // Only a reading of the file this host was last asked
+                        // to load carries its episode's name.
+                        media = currentMedia.takeIf { values.generation() == currentGeneration },
+                        videoWidth = values[WIDTH],
+                        videoHeight = values[HEIGHT],
+                        endReason = EndReason.of(values[END_REASON]),
+                        buffering = values[BUFFERING] != 0.0,
+                        cachePercent = values[CACHE_PERCENT],
+                        seeking = values[SEEKING] != 0.0,
+                        cachedUntil = values[CACHED_UNTIL],
+                    )
                     mutableState.value = next
-                    onStateChanged?.invoke(next)
+                    // The listeners drive the media session and the player UI,
+                    // both of which are the main thread's.
+                    withContext(Dispatchers.Main) { onStateChanged?.invoke(next) }
+                    refreshChapters(next)
+                    if (values[LOADED] != 0.0 && values.generation() == currentGeneration &&
+                        subtitlesCheckedFor != currentGeneration
+                    ) {
+                        subtitlesCheckedFor = currentGeneration
+                        preferFullSubtitles()
+                    }
                 }
+                withOpenHandle(::nativeTakeError)?.let { mutableProblem.value = it }
                 if (tick++ % 4 == 0) refreshTracks()
                 delay(250)
             }
         }
     }
 
+    /**
+     * Re-read the chapters when there is a reason to: a different file, or a
+     * duration that has only just arrived. Both change the answer — the length
+     * of a chapter is what settles whether `Intro` is an opening or ten minutes
+     * of story — and neither changes again after that, so this settles quickly
+     * and then costs one comparison per poll.
+     */
+    private fun refreshChapters(state: MpvPlaybackState) {
+        val generation = currentGeneration
+        val wanted = state.duration to generation.toRawBits()
+        if (plannedFor == wanted) return
+        runCatching {
+            val encoded = withOpenHandle(::nativeChapters) ?: return
+            val values = JSONArray(encoded)
+            List(values.length()) { index ->
+                values.getJSONObject(index).run {
+                    ChapterRecord(
+                        index = getLong("index"),
+                        title = optString("title").takeIf(String::isNotBlank),
+                        start = getDouble("start"),
+                    )
+                }
+            }
+        }.onSuccess { chapters ->
+            plannedFor = wanted
+            mutableChapters.value = chapterPlan(chapters, state.duration.takeIf { it > 0.0 })
+        }
+    }
+
+    /**
+     * Play the dialogue rather than the signs and songs mpv picked by language
+     * (`pstr_core::subtitles`). Not remembered: it is the choice mpv should
+     * have made, not the viewer's.
+     */
+    private fun preferFullSubtitles() {
+        refreshTracks()
+        val subtitles = mutableTracks.value.filter { it.type == "sub" }
+        val id = fullSubtitlesInstead(
+            subtitles.map {
+                SubtitleTrackRecord(it.id, it.language, it.title, it.isDefault, it.forced, it.selected)
+            },
+        ) ?: return
+        subtitles.firstOrNull { it.id == id }?.let(::selectTrack)
+    }
+
     private fun refreshTracks() {
         runCatching {
             val encoded = withOpenHandle(::nativeTracks) ?: return
             val values = JSONArray(encoded)
             List(values.length()) { index ->
                 values.getJSONObject(index).run {
-                    MpvTrack(getLong("id"), getString("type"), getString("language"), getString("title"), getBoolean("selected"))
+                    MpvTrack(
+                        getLong("id"), getString("type"), getString("language"), getString("title"),
+                        getBoolean("selected"), optBoolean("default"), optBoolean("forced"),
+                    )
                 }
             }
         }.onSuccess { mutableTracks.value = it }
@@ -149,16 +431,28 @@ class NativeMpvHost : LibmpvHost, AutoCloseable {
 
     override fun close() {
         scope.cancel()
-        lifecycle.withLock {
+        val destroy = lifecycle.withLock {
-            if (closed) return@withLock
+            if (closed) return@withLock false
             closed = true
             onPlaybackStarted = null
             onStateChanged = null
             onExplicitStop = null
-            nativeDestroy(nativeHandle)
+            onSkipPrevious = null
-            currentStreamHandle?.let(::pstrAndroidStreamRelease)
+            onSkipNext = null
-            currentStreamHandle = null
+            mutableNowPlaying.value = null
+            mutableAdvancing.value = false
+            true
         }
+        if (!destroy) return
+        // `mpv_terminate_destroy` joins mpv's demuxer thread, which may be
+        // parked in a block fetch over a degraded connection. This is called
+        // from Service.onDestroy — on the main thread — so waiting for it there
+        // is an ANR. `closed` is already set, so nothing new enters the handle;
+        // the lock is only to let a call that is already inside finish.
+        //
+        // Terminating the core closes the open file, and closing it releases the
+        // stream — after mpv's last read rather than during it.
+        Thread({ lifecycle.withLock { nativeDestroy(nativeHandle) } }, "pstr-mpv-teardown").start()
     }
 
     /** Serializes destruction against every JNI use of the raw Player pointer. */
@@ -166,25 +460,72 @@ class NativeMpvHost : LibmpvHost, AutoCloseable {
         if (closed) null else block(nativeHandle)
     }
 
-    private external fun nativeCreate(): Long
     private external fun nativeDestroy(handle: Long)
     private external fun nativeAttachSurface(handle: Long, surface: Surface)
     private external fun nativeDetachSurface(handle: Long)
-    private external fun nativeLoad(handle: Long, stream: Long, start: Double, audio: String?, subtitle: String?, subtitles: Boolean): Boolean
+    private external fun nativeLoad(
+        handle: Long,
+        stream: Long,
+        start: Double,
+        audio: String?,
+        subtitle: String?,
+        subtitles: Boolean,
+        hardwareDecoding: Boolean,
+    ): Boolean
+    private external fun nativeAddSubtitle(
+        handle: Long,
+        generation: Long,
+        stream: Long,
+        title: String,
+        language: String?,
+        select: Boolean,
+    )
     private external fun nativePause(handle: Long, paused: Boolean)
     private external fun nativeSeek(handle: Long, position: Double)
     private external fun nativeVolume(handle: Long, volume: Double)
+    private external fun nativeSpeed(handle: Long, speed: Double)
     private external fun nativeMute(handle: Long, muted: Boolean)
     private external fun nativeSelectTrack(handle: Long, audio: Boolean, track: Long)
     private external fun nativeStop(handle: Long)
     private external fun nativeState(handle: Long): DoubleArray
-    private external fun nativeTracks(handle: Long): String
+    private external fun nativeTakeError(handle: Long): String?
+    // Nullable: `NewStringUTF` returns null when the string cannot be built,
+    // and a non-null declaration turns that into an NPE that `runCatching`
+    // swallows into a silently empty track list.
+    private external fun nativeTracks(handle: Long): String?
+    private external fun nativeChapters(handle: Long): String?
     private external fun pstrAndroidStreamRelease(handle: Long)
 
+    private fun DoubleArray.generation(): Double = getOrElse(GENERATION) { -1.0 }
+
     companion object {
+        /** Fields `nativeState` fills, in the order `pstr_mpv.cpp` writes them. */
+        private const val FIELDS = 15
+        private const val GENERATION = 6
+        private const val WIDTH = 7
+        private const val HEIGHT = 8
+        private const val END_REASON = 9
+        private const val BUFFERING = 10
+        private const val CACHE_PERCENT = 11
+        private const val SEEKING = 12
+        private const val CACHED_UNTIL = 13
+        private const val LOADED = 14
+
         init {
             System.loadLibrary("pstr_android")
             System.loadLibrary("pstr_mpv")
         }
+
+        /**
+         * A host over a live libmpv core, or null if libmpv would not start.
+         *
+         * Null rather than an exception: the service that owns this is created
+         * by the system, so a throw out of the constructor takes the process
+         * with it — and the app has a graceful "this build does not include
+         * libmpv" screen that a crash makes unreachable.
+         */
+        fun createOrNull(): NativeMpvHost? = nativeCreate().takeIf { it != 0L }?.let(::NativeMpvHost)
+
+        @JvmStatic private external fun nativeCreate(): Long
     }
 }

android/app/src/main/java/io/narl/protonstream/playback/PlaybackService.kt

@@ -5,7 +5,12 @@ import android.app.NotificationChannel
 import android.app.NotificationManager
 import android.app.PendingIntent
 import android.app.Service
+import android.content.BroadcastReceiver
+import android.content.Context
 import android.content.Intent
+import android.content.IntentFilter
+import android.graphics.Bitmap
+import android.graphics.drawable.Icon
 import android.media.AudioAttributes
 import android.media.AudioFocusRequest
 import android.media.AudioManager
@@ -14,119 +19,382 @@ import android.media.session.MediaSession
 import android.media.session.PlaybackState
 import android.os.Binder
 import android.os.IBinder
+import android.os.SystemClock
+import androidx.core.content.ContextCompat
 import io.narl.protonstream.MainActivity
+import io.narl.protonstream.R
+import io.narl.protonstream.native.NativeRuntime
 import io.narl.protonstream.settings.SettingsStore
+import io.narl.protonstream.ui.loadArtwork
+import io.narl.protonstream.ui.loadThumbnail
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.SupervisorJob
+import kotlinx.coroutines.cancel
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.runBlocking
+import kotlinx.coroutines.withContext
+import kotlinx.coroutines.withTimeoutOrNull
 
-/** Owns libmpv so audio survives Activity recreation, rotation and PiP. */
+/** Owns libmpv so audio survives Activity recreation and rotation. */
 class PlaybackService : Service() {
     inner class PlaybackBinder : Binder() {
-        val host: NativeMpvHost get() = this@PlaybackService.host
+        val host: NativeMpvHost? get() = this@PlaybackService.host
     }
 
-    private lateinit var host: NativeMpvHost
+    /**
+     * The libmpv core, or null when this build could not start one.
+     *
+     * Nullable rather than a `lateinit` that throws: the system creates this
+     * service, so a failure in its constructor takes the process down and makes
+     * the app's own "playback is unavailable" screen unreachable.
+     */
+    private var host: NativeMpvHost? = null
     private lateinit var mediaSession: MediaSession
     private lateinit var audioManager: AudioManager
+    private val scope = CoroutineScope(SupervisorJob() + Dispatchers.Main.immediate)
     private var audioFocus: AudioFocusRequest? = null
-    private var notifiedPaused: Boolean? = null
+    /** Whether the pause on screen is this service's doing, not the viewer's. */
+    private var pausedForFocus = false
+    /** The volume before ducking, so the restore does not read a ducked one. */
+    private var beforeDucking: Double? = null
+    /**
+     * Pulling the headphone jack must not continue on the speaker.
+     *
+     * Android broadcasts this and expects every media app to handle it; the
+     * alternative is an episode playing out loud in a quiet room.
+     */
+    private val becomingNoisy = object : BroadcastReceiver() {
+        override fun onReceive(context: Context?, intent: Intent?) {
+            if (intent?.action == AudioManager.ACTION_AUDIO_BECOMING_NOISY) host?.setPaused(true)
+        }
+    }
     private var foregroundPlayback = false
     private var sessionPlayback = false
+    /**
+     * What the posted notification already says.
+     *
+     * The state poll runs four times a second and almost none of those readings
+     * change anything the shade shows. Re-posting on every one of them animates
+     * the media control and costs a binder round trip per tick, so the
+     * notification is rebuilt only when its own inputs move.
+     */
+    private var notified: NotificationShape? = null
+    /** The pending teardown, held so an episode transition can call it off. */
+    private var retire: Job? = null
+    /** The open episode's latest reading, which [track] saves. */
+    private var lastReading: MpvPlaybackState? = null
+    private var lastSave = 0L
+    /** The episode's artwork, and the source key it was fetched for. */
+    private var artwork: Pair<String, Bitmap>? = null
     private val binder = PlaybackBinder()
 
     override fun onCreate() {
         super.onCreate()
         createChannel()
+        ContextCompat.registerReceiver(
+            this,
+            becomingNoisy,
+            IntentFilter(AudioManager.ACTION_AUDIO_BECOMING_NOISY),
+            ContextCompat.RECEIVER_NOT_EXPORTED,
+        )
         audioManager = getSystemService(AudioManager::class.java)
-        host = NativeMpvHost().apply {
+        host = NativeMpvHost.createOrNull()?.apply {
             onPlaybackStarted = {
-                requestAudioFocus()
+                // A refusal is rare — a call in progress — but playing over it
+                // is worse than not playing, and the viewer can simply press
+                // play again once the call ends.
+                if (!requestAudioFocus()) setPaused(true)
                 sessionPlayback = true
-                if (SettingsStore(this@PlaybackService).backgroundAudio) {
+                cancelRetire()
+                if (!foregroundPlayback && SettingsStore(this@PlaybackService).backgroundAudio) {
                     // Convert the bound service into a started foreground
                     // service only when the viewer opted to keep audio alive.
-                    startService(Intent(this@PlaybackService, PlaybackService::class.java))
+                    // Already-foreground is the ordinary case across an episode
-                    startForeground(NOTIFICATION_ID, notification(false))
+                    // transition, and re-entering costs a notification rebuild.
-                    foregroundPlayback = true
+                    foregroundPlayback = runCatching {
+                        startService(Intent(this@PlaybackService, PlaybackService::class.java))
+                        startForeground(NOTIFICATION_ID, notification(state.value, nowPlaying.value))
+                    }.isSuccess
                 }
                 mediaSession.isActive = true
             }
-            onStateChanged = { updateSession(it) }
+            onStateChanged = { updateSession(it); track(it) }
             onExplicitStop = { retirePlayback() }
         }
         mediaSession = MediaSession(this, "proton-stream").apply {
+            setSessionActivity(openActivity())
             setCallback(object : MediaSession.Callback() {
-                override fun onPlay() = host.setPaused(false)
+                override fun onPlay() { host?.setPaused(false) }
-                override fun onPause() = host.setPaused(true)
+                override fun onPause() { host?.setPaused(true) }
-                override fun onSeekTo(pos: Long) = host.seek(pos / 1_000.0)
+                override fun onSeekTo(pos: Long) { host?.seek(pos / 1_000.0) }
-                override fun onStop() = host.stop()
+                override fun onStop() { host?.stop() }
+                override fun onSkipToNext() { host?.onSkipNext?.invoke() }
+                override fun onSkipToPrevious() { host?.onSkipPrevious?.invoke() }
             })
         }
+        // Artwork arrives after the episode does, and the shape of the transport
+        // changes with the playlist position, so the notification follows the
+        // published episode rather than being built once when playback starts.
+        val core = host ?: return
+        scope.launch {
+            core.nowPlaying.collect { playing ->
+                // Keyed by whichever source the episode has: with metadata off
+                // there is no provider poster, and Proton's own thumbnail is
+                // the only thing the shade can show.
+                artwork = playing?.let { episode ->
+                    val key = episode.artworkUrl ?: episode.artworkFile?.key ?: return@let null
+                    artwork?.takeIf { it.first == key }
+                        ?: (
+                            loadArtwork(this@PlaybackService, episode.artworkUrl)
+                                ?: loadThumbnail(episode.artworkFile)
+                            )?.let { key to it }
+                }
+                refreshSession(core.state.value, playing)
+            }
+        }
     }
 
     override fun onBind(intent: Intent?): IBinder = binder
 
     override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
         when (intent?.action) {
-            ACTION_PLAY -> host.setPaused(false)
+            ACTION_PLAY -> host?.setPaused(false)
-            ACTION_PAUSE -> host.setPaused(true)
+            ACTION_PAUSE -> host?.setPaused(true)
-            ACTION_STOP -> host.stop()
+            ACTION_PREVIOUS -> host?.onSkipPrevious?.invoke()
+            ACTION_NEXT -> host?.onSkipNext?.invoke()
+            ACTION_STOP -> host?.stop()
         }
         return START_NOT_STICKY
     }
 
+    /**
+     * Swiped away from Recents. With background audio on, this service would
+     * otherwise play on with no screen to return to and no autoplay, so it
+     * saves where the episode got to and stops.
+     */
+    override fun onTaskRemoved(rootIntent: Intent?) {
+        lastReading?.let { reading ->
+            // Bounded and on this thread: the process may go as soon as the
+            // service stops, and a save launched into its scope would go with it.
+            runBlocking { withTimeoutOrNull(SAVE_ON_EXIT_MS) { withContext(Dispatchers.IO) { save(reading) } } }
+        }
+        host?.stop()
+        retirePlayback()
+        super.onTaskRemoved(rootIntent)
+    }
+
     override fun onDestroy() {
+        scope.cancel()
+        runCatching { unregisterReceiver(becomingNoisy) }
         audioFocus?.let(audioManager::abandonAudioFocusRequest)
         mediaSession.release()
-        host.close()
+        host?.close()
         super.onDestroy()
     }
 
-    private fun requestAudioFocus() {
+    /**
+     * Take audio focus, and honour what the system says about it afterwards.
+     *
+     * The four cases are genuinely different and collapsing them is what made
+     * this feel broken: a phone call is transient and playback should come back
+     * by itself; a navigation prompt wants the volume down, not a pause; another
+     * media app taking over for good means giving the focus back rather than
+     * holding it; and a refusal means not playing at all.
+     */
+    private fun requestAudioFocus(): Boolean {
         audioFocus?.let(audioManager::abandonAudioFocusRequest)
         val request = AudioFocusRequest.Builder(AudioManager.AUDIOFOCUS_GAIN)
             .setAudioAttributes(
                 AudioAttributes.Builder().setUsage(AudioAttributes.USAGE_MEDIA)
                     .setContentType(AudioAttributes.CONTENT_TYPE_MOVIE).build(),
             )
+            .setWillPauseWhenDucked(false)
             .setOnAudioFocusChangeListener { focus ->
                 when (focus) {
-                    AudioManager.AUDIOFOCUS_LOSS, AudioManager.AUDIOFOCUS_LOSS_TRANSIENT -> host.setPaused(true)
+                    AudioManager.AUDIOFOCUS_LOSS -> {
-                    AudioManager.AUDIOFOCUS_GAIN -> Unit
+                        pausedForFocus = false
+                        audioFocus?.let(audioManager::abandonAudioFocusRequest)
+                        audioFocus = null
+                        host?.setPaused(true)
+                    }
+                    AudioManager.AUDIOFOCUS_LOSS_TRANSIENT -> {
+                        // Only resume what this paused: a viewer who paused
+                        // before the phone rang expects it still paused after.
+                        pausedForFocus = host?.state?.value?.paused == false
+                        host?.setPaused(true)
+                    }
+                    AudioManager.AUDIOFOCUS_LOSS_TRANSIENT_CAN_DUCK -> {
+                        host?.let { core ->
+                            val current = core.state.value.volume
+                            beforeDucking = beforeDucking ?: current
+                            core.setVolume(current * DUCK_FACTOR)
+                        }
+                    }
+                    AudioManager.AUDIOFOCUS_GAIN -> {
+                        beforeDucking?.let { host?.setVolume(it) }
+                        beforeDucking = null
+                        if (pausedForFocus) {
+                            pausedForFocus = false
+                            host?.setPaused(false)
+                        }
+                    }
                 }
             }.build()
         audioFocus = request
-        audioManager.requestAudioFocus(request)
+        return audioManager.requestAudioFocus(request) == AudioManager.AUDIOFOCUS_REQUEST_GRANTED
+    }
+
+    /**
+     * Keep the resume position from here rather than from the player screen.
+     *
+     * This service outlives the activity whenever background audio is on, and a
+     * position the screen alone kept stopped being saved the moment the screen
+     * went. Readings are attributed by [MpvPlaybackState.media], so an episode
+     * change saves the outgoing episode's last reading before the new one's.
+     */
+    private fun track(state: MpvPlaybackState) {
+        val media = state.media ?: return
+        if (state.duration <= 0.0) return
+        val previous = lastReading
+        lastReading = state
+        val now = SystemClock.elapsedRealtime()
+        val due = when {
+            previous != null && previous.media != media -> {
+                scope.launch(Dispatchers.IO) { save(previous) }
+                true
+            }
+            state.ended -> previous?.ended != true
+            state.paused -> previous?.paused != true
+            else -> now - lastSave >= SAVE_EVERY_MS
+        }
+        if (due) {
+            lastSave = now
+            scope.launch(Dispatchers.IO) { save(state) }
+        }
+    }
+
+    private suspend fun save(state: MpvPlaybackState) {
+        val media = state.media ?: return
+        // Played to the end, or near enough that what is left is credits. A
+        // failure or a stop also "ends", and recording either as watched would
+        // retire an episode nobody saw.
+        val watched = state.endReason == EndReason.Eof || state.position >= state.duration * WATCHED_FRACTION
+        runCatching {
+            NativeRuntime.engine().saveWatchState(
+                media.substringBeforeLast(':'),
+                media.substringAfterLast(':'),
+                state.position.coerceIn(0.0, state.duration),
+                state.duration,
+                watched,
+            )
+        }
     }
 
     private fun updateSession(state: MpvPlaybackState) {
+        refreshSession(state, host?.nowPlaying?.value)
+        if (state.ended) scheduleRetire() else cancelRetire()
+    }
+
+    /**
+     * Retire the session once playback is really over.
+     *
+     * "This file ended" is not "playback is over": autoplay walks to the next
+     * episode, and opening its stream is a network round trip. Retiring inside
+     * that gap leaves the app with no foreground state at all, so the
+     * `startForeground` on the far side is a background start — which API 31+
+     * refuses with `ForegroundServiceStartNotAllowedException`, and this app's
+     * minSdk is 31.
+     */
+    private fun scheduleRetire() {
+        if (retire?.isActive == true) return
+        retire = scope.launch {
+            // The end of file reaches the player and this service from the same
+            // poll, and the player's advance is a recomposition behind. Give it
+            // that long to declare a transition before concluding there is none.
+            delay(TRANSITION_SETTLE_MS)
+            val host = this@PlaybackService.host ?: return@launch
+            withTimeoutOrNull(TRANSITION_GRACE_MS) { host.advancing.first { !it } }
+            if (host.state.value.ended) retirePlayback()
+        }
+    }
+
+    private fun cancelRetire() {
+        retire?.cancel()
+        retire = null
+    }
+
+    private fun refreshSession(state: MpvPlaybackState, playing: NowPlaying?) {
         val status = when {
             state.ended -> PlaybackState.STATE_STOPPED
             state.paused -> PlaybackState.STATE_PAUSED
             else -> PlaybackState.STATE_PLAYING
         }
+        var actions = PlaybackState.ACTION_PLAY or PlaybackState.ACTION_PAUSE or
+            PlaybackState.ACTION_PLAY_PAUSE or PlaybackState.ACTION_SEEK_TO or PlaybackState.ACTION_STOP
+        if (playing?.hasNext == true) actions = actions or PlaybackState.ACTION_SKIP_TO_NEXT
+        if (playing?.hasPrevious == true) actions = actions or PlaybackState.ACTION_SKIP_TO_PREVIOUS
         mediaSession.setPlaybackState(
             PlaybackState.Builder()
-                .setActions(PlaybackState.ACTION_PLAY or PlaybackState.ACTION_PAUSE or PlaybackState.ACTION_SEEK_TO or PlaybackState.ACTION_STOP)
+                .setActions(actions)
                 .setState(status, (state.position * 1_000).toLong(), if (state.paused) 0f else 1f)
                 .build(),
         )
-        mediaSession.setMetadata(
+        mediaSession.setMetadata(metadata(state, playing))
-            MediaMetadata.Builder().putLong(MediaMetadata.METADATA_KEY_DURATION, (state.duration * 1_000).toLong()).build(),
+        val shape = NotificationShape(
+            paused = state.paused,
+            media = playing?.media,
+            title = playing?.title,
+            subtitle = playing?.show,
+            hasPrevious = playing?.hasPrevious == true,
+            hasNext = playing?.hasNext == true,
+            hasArtwork = artwork != null,
         )
-        if (state.ended && foregroundPlayback) {
+        if (foregroundPlayback && notified != shape) {
-            host.releaseEndedStream()
+            notified = shape
-            retirePlayback()
+            getSystemService(NotificationManager::class.java)
-            return
+                .notify(NOTIFICATION_ID, notification(state, playing))
-        }
-        if (foregroundPlayback && notifiedPaused != state.paused) {
-            notifiedPaused = state.paused
-            getSystemService(NotificationManager::class.java).notify(NOTIFICATION_ID, notification(state.paused))
         }
     }
 
+    /**
+     * What the shade, the lock screen and Android Auto read.
+     *
+     * The episode is the title and the show is the artist, which is the mapping
+     * every media surface already lays out well: one prominent line, one
+     * secondary, and the poster behind both.
+     */
+    private fun metadata(state: MpvPlaybackState, playing: NowPlaying?): MediaMetadata =
+        MediaMetadata.Builder()
+            .putString(MediaMetadata.METADATA_KEY_TITLE, playing?.title ?: "proton-stream")
+            .putString(MediaMetadata.METADATA_KEY_DISPLAY_TITLE, playing?.title ?: "proton-stream")
+            .apply {
+                playing?.show?.let {
+                    putString(MediaMetadata.METADATA_KEY_ARTIST, it)
+                    putString(MediaMetadata.METADATA_KEY_ALBUM, it)
+                    putString(MediaMetadata.METADATA_KEY_DISPLAY_SUBTITLE, it)
+                }
+                playing?.detail?.let {
+                    putString(MediaMetadata.METADATA_KEY_DISPLAY_DESCRIPTION, it)
+                }
+                artwork?.second?.let {
+                    putBitmap(MediaMetadata.METADATA_KEY_ALBUM_ART, it)
+                    putBitmap(MediaMetadata.METADATA_KEY_ART, it)
+                    putBitmap(MediaMetadata.METADATA_KEY_DISPLAY_ICON, it)
+                }
+            }
+            .putLong(MediaMetadata.METADATA_KEY_DURATION, (state.duration * 1_000).toLong())
+            .build()
+
     private fun retirePlayback() {
+        cancelRetire()
         if (!sessionPlayback && !foregroundPlayback) return
         sessionPlayback = false
-        notifiedPaused = null
+        notified = null
+        artwork = null
         mediaSession.isActive = false
         audioFocus?.let(audioManager::abandonAudioFocusRequest)
         audioFocus = null
@@ -135,40 +403,101 @@ class PlaybackService : Service() {
         stopSelf()
     }
 
-    private fun notification(paused: Boolean): Notification {
+    private fun openActivity(): PendingIntent = PendingIntent.getActivity(
-        val open = PendingIntent.getActivity(
+        this,
-            this, 0, Intent(this, MainActivity::class.java), PendingIntent.FLAG_IMMUTABLE or PendingIntent.FLAG_UPDATE_CURRENT,
+        0,
-        )
+        Intent(this, MainActivity::class.java),
-        val toggleAction = if (paused) ACTION_PLAY else ACTION_PAUSE
+        PendingIntent.FLAG_IMMUTABLE or PendingIntent.FLAG_UPDATE_CURRENT,
-        val toggle = PendingIntent.getService(
+    )
-            this, 1, Intent(this, PlaybackService::class.java).setAction(toggleAction), PendingIntent.FLAG_IMMUTABLE or PendingIntent.FLAG_UPDATE_CURRENT,
+
-        )
+    private fun command(requestCode: Int, action: String): PendingIntent = PendingIntent.getService(
-        val stop = PendingIntent.getService(
+        this,
-            this, 2, Intent(this, PlaybackService::class.java).setAction(ACTION_STOP), PendingIntent.FLAG_IMMUTABLE or PendingIntent.FLAG_UPDATE_CURRENT,
+        requestCode,
-        )
+        Intent(this, PlaybackService::class.java).setAction(action),
+        PendingIntent.FLAG_IMMUTABLE or PendingIntent.FLAG_UPDATE_CURRENT,
+    )
+
+    private fun action(icon: Int, label: String, requestCode: Int, name: String): Notification.Action =
+        Notification.Action.Builder(Icon.createWithResource(this, icon), label, command(requestCode, name)).build()
+
+    private fun notification(state: MpvPlaybackState, playing: NowPlaying?): Notification {
+        val paused = state.paused
+        val actions = buildList {
+            if (playing?.hasPrevious == true) {
+                add(action(android.R.drawable.ic_media_previous, "Previous", 3, ACTION_PREVIOUS))
+            }
+            add(
+                if (paused) action(android.R.drawable.ic_media_play, "Play", 1, ACTION_PLAY)
+                else action(android.R.drawable.ic_media_pause, "Pause", 1, ACTION_PAUSE),
+            )
+            if (playing?.hasNext == true) {
+                add(action(android.R.drawable.ic_media_next, "Next", 4, ACTION_NEXT))
+            }
+            add(action(android.R.drawable.ic_menu_close_clear_cancel, "Stop", 2, ACTION_STOP))
+        }
+        val style = Notification.MediaStyle()
+            .setMediaSession(mediaSession.sessionToken)
+            // The compact view holds three: the transport as it exists for this
+            // episode, so a first episode does not show a dead Previous.
+            .setShowActionsInCompactView(*IntArray(minOf(3, actions.size)) { it })
         return Notification.Builder(this, CHANNEL_ID)
-            .setSmallIcon(android.R.drawable.ic_media_play)
+            .setSmallIcon(R.drawable.ic_notification_stream)
-            .setContentTitle("proton-stream")
+            .setContentTitle(playing?.title ?: "proton-stream")
-            .setContentText(if (paused) "Playback paused" else "Playing")
+            .setContentText(playing?.show ?: playing?.detail ?: if (paused) "Paused" else "Playing")
-            .setContentIntent(open)
+            .apply {
+                playing?.takeIf { it.show != null }?.detail?.let { setSubText(it) }
+                artwork?.second?.let { setLargeIcon(it) }
+            }
+            .setColor(ACCENT)
+            .setColorized(true)
+            .setContentIntent(openActivity())
+            .setDeleteIntent(command(2, ACTION_STOP))
+            .setVisibility(Notification.VISIBILITY_PUBLIC)
             .setOngoing(!paused)
-            .addAction(Notification.Action.Builder(null, if (paused) "Play" else "Pause", toggle).build())
+            .apply { actions.forEach { addAction(it) } }
-            .addAction(Notification.Action.Builder(null, "Stop", stop).build())
+            .setStyle(style)
-            .setStyle(Notification.MediaStyle().setMediaSession(mediaSession.sessionToken).setShowActionsInCompactView(0, 1))
             .build()
     }
 
     private fun createChannel() {
         getSystemService(NotificationManager::class.java).createNotificationChannel(
-            NotificationChannel(CHANNEL_ID, "Playback", NotificationManager.IMPORTANCE_LOW),
+            NotificationChannel(CHANNEL_ID, "Playback", NotificationManager.IMPORTANCE_LOW).apply {
+                description = "Transport controls for the episode being played."
+                setShowBadge(false)
+            },
         )
     }
 
+    /** The inputs the posted notification is built from, and nothing else. */
+    private data class NotificationShape(
+        val paused: Boolean,
+        val media: String?,
+        val title: String?,
+        val subtitle: String?,
+        val hasPrevious: Boolean,
+        val hasNext: Boolean,
+        val hasArtwork: Boolean,
+    )
+
     companion object {
         private const val CHANNEL_ID = "playback"
         private const val NOTIFICATION_ID = 47
+        /** How long a player gets to declare that it is changing episodes. */
+        private const val TRANSITION_SETTLE_MS = 1_000L
+        /** And how long that transition may then take before it is abandoned. */
+        private const val TRANSITION_GRACE_MS = 30_000L
+        /** How far the volume drops for a navigation prompt or a notification. */
+        private const val DUCK_FACTOR = 0.3
+        private const val SAVE_EVERY_MS = 5_000L
+        /** How long a swipe from Recents may hold the main thread to save. */
+        private const val SAVE_ON_EXIT_MS = 2_000L
+
+        /** Catppuccin Mocha mauve, the accent the app is themed with. */
+        private const val ACCENT = 0xFFCBA6F7.toInt()
         private const val ACTION_PLAY = "io.narl.protonstream.PLAY"
         private const val ACTION_PAUSE = "io.narl.protonstream.PAUSE"
+        private const val ACTION_PREVIOUS = "io.narl.protonstream.PREVIOUS"
+        private const val ACTION_NEXT = "io.narl.protonstream.NEXT"
         private const val ACTION_STOP = "io.narl.protonstream.STOP"
     }
 }

android/app/src/main/java/io/narl/protonstream/playback/StreamSession.kt

@@ -0,0 +1,103 @@
+package io.narl.protonstream.playback
+
+import android.view.Surface
+import io.narl.protonstream.native.NativeRuntime
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.SupervisorJob
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+import uniffi.pstr_android.AndroidEngine
+import uniffi.pstr_android.AndroidStream
+import uniffi.pstr_android.EpisodeRecord
+
+/** Exact seekable stream contract a bundled libmpv JNI adapter must consume. */
+class RustStreamSession(
+    private val episode: EpisodeRecord,
+) {
+    private var engine: AndroidEngine? = null
+    private var stream: AndroidStream? = null
+    private var handle: ULong? = null
+    private var streamSize: ULong? = null
+
+    suspend fun open(): RustStreamSession = withContext(Dispatchers.IO) {
+        val openedEngine = NativeRuntime.engine()
+        engine = openedEngine
+        stream = openedEngine.openStream(episode.shareId, episode.volumeId, episode.linkId).also {
+            streamSize = it.size()
+            handle = it.nativeHandle()
+        }
+        this@RustStreamSession
+    }
+
+    fun nativeHandle(): ULong = checkNotNull(handle) { "stream is not published" }
+
+    fun size(): ULong = checkNotNull(streamSize) { "stream is not open" }
+
+    fun releaseNative(host: LibmpvHost) {
+        handle?.let(host::releaseNativeStream)
+        handle = null
+        streamSize = null
+        stream = null
+    }
+
+    /** The native player now owns the published token until stop/end/close. */
+    fun transferToPlayer() {
+        handle = null
+        streamSize = null
+        stream = null
+    }
+
+    /**
+     * Give the episode's stream back to Rust, from a scope of this session's own.
+     *
+     * Deliberately not the caller's: the one moment this has to run is when the
+     * player leaves the composition, which is the same moment a
+     * `rememberCoroutineScope` is cancelled — so a release launched there is
+     * cancelled before it starts, and the stream is held for the life of the
+     * process. Once per episode played, that is every episode.
+     */
+    fun close(host: LibmpvHost) {
+        releaseNative(host)
+        sessions.launch {
+            runCatching { engine?.releaseStream(episode.shareId, episode.volumeId, episode.linkId) }
+            engine = null
+        }
+    }
+}
+
+/**
+ * Where stream teardown runs: process-lifetime, like the engine it releases to,
+ * and never cancelled by a screen going away.
+ */
+private val sessions = CoroutineScope(SupervisorJob() + Dispatchers.IO)
+
+/** Implement only in the variant that bundles a pinned libmpv native artifact. */
+interface LibmpvHost {
+    fun attachSurface(surface: Surface)
+    fun detachSurface()
+
+    /**
+     * Consumes the opaque handle through pstr_android_stream_{read,size}.
+     *
+     * [media] names the episode being loaded. One host serves every episode in
+     * turn, so its readings have to say which one they describe — see
+     * [MpvPlaybackState.media].
+     */
+    suspend fun play(
+        media: String,
+        nativeHandle: ULong,
+        size: ULong,
+        startPosition: Double = 0.0,
+        audioLanguage: String? = null,
+        subtitleLanguage: String? = null,
+        subtitles: Boolean = true,
+        hardwareDecoding: Boolean = true,
+    )
+
+    /** Calls pstr_android_stream_release exactly once for a published handle. */
+    fun releaseNativeStream(nativeHandle: ULong)
+}
+
+/** How an episode is named in watch state, work names and player readings. */
+fun mediaKey(episode: EpisodeRecord) = "${episode.shareId}:${episode.linkId}"

android/app/src/main/java/io/narl/protonstream/settings/SettingsStore.kt

@@ -1,7 +1,15 @@
 package io.narl.protonstream.settings
 
 import android.content.Context
+import androidx.core.content.edit
 
+/**
+ * The settings that are Android's alone.
+ *
+ * Playback preferences — volume, languages, autoplay, auto-skip — deliberately
+ * do *not* live here: they are `pstr_core::prefs`, reached over the bridge, so
+ * there is one definition of them rather than one per front end.
+ */
 class SettingsStore(context: Context) {
     private val preferences = context.getSharedPreferences(NAME, Context.MODE_PRIVATE)
 
@@ -13,9 +21,69 @@ class SettingsStore(context: Context) {
         get() = preferences.getBoolean(KEY_BACKGROUND_AUDIO, true)
         set(value) { preferences.edit().putBoolean(KEY_BACKGROUND_AUDIO, value).apply() }
 
-    private companion object {
+    /**
-        const val NAME = "proton_stream_settings"
+     * Whether mpv may decode in hardware. Off is the way out for a device whose
-        const val KEY_WIFI_ONLY = "wifi_only"
+     * MediaCodec decoder shows green or torn frames; it costs battery, so it is
-        const val KEY_BACKGROUND_AUDIO = "background_audio"
+     * on unless the viewer turns it off. Read at each load, so a change applies
+     * from the next file.
+     */
+    var hardwareDecoding: Boolean
+        get() = preferences.getBoolean(KEY_HARDWARE_DECODING, true)
+        set(value) { preferences.edit().putBoolean(KEY_HARDWARE_DECODING, value).apply() }
+
+    /** The streaming cache's budget, in GiB. See [CACHE_BUDGET_CHOICES]. */
+    var cacheBudgetGib: Int
+        get() = preferences.getInt(KEY_CACHE_BUDGET_GIB, DEFAULT_CACHE_BUDGET_GIB)
+        set(value) { preferences.edit().putInt(KEY_CACHE_BUDGET_GIB, value).apply() }
+
+    /** How the library was last sorted, as a `LibrarySort` name; null for the default. */
+    var librarySort: String?
+        get() = preferences.getString(KEY_LIBRARY_SORT, null)
+        set(value) { preferences.edit { putString(KEY_LIBRARY_SORT, value) } }
+
+    /** The library's offer of posters and synopses was turned down. */
+    var metadataOfferDismissed: Boolean
+        get() = preferences.getBoolean(KEY_METADATA_OFFER_DISMISSED, false)
+        set(value) { preferences.edit { putBoolean(KEY_METADATA_OFFER_DISMISSED, value) } }
+
+    /** Which titles the library last showed, as a `LibraryFilter` name; null for all. */
+    var libraryFilter: String?
+        get() = preferences.getString(KEY_LIBRARY_FILTER, null)
+        set(value) { preferences.edit { putString(KEY_LIBRARY_FILTER, value) } }
+
+    /** Whether the library folds each franchise into one tile. */
+    var libraryGrouped: Boolean
+        get() = preferences.getBoolean(KEY_LIBRARY_GROUPED, true)
+        set(value) { preferences.edit { putBoolean(KEY_LIBRARY_GROUPED, value) } }
+
+    /** Whether a background crawl may say that a show gained episodes. */
+    var newEpisodeNotifications: Boolean
+        get() = preferences.getBoolean(KEY_NEW_EPISODE_NOTIFICATIONS, true)
+        set(value) { preferences.edit { putBoolean(KEY_NEW_EPISODE_NOTIFICATIONS, value) } }
+
+    companion object {
+        /** The desktop's range, in the steps a phone's storage is bought in. */
+        val CACHE_BUDGET_CHOICES = listOf(1, 2, 4, 8, 16)
+
+        /** `DiskCacheConfig::DEFAULT_BUDGET_BYTES`, so an unset choice changes nothing. */
+        const val DEFAULT_CACHE_BUDGET_GIB = 4
+
+        fun gibToBytes(gib: Int): ULong = gib.toULong() * 1024uL * 1024uL * 1024uL
+
+        /** Load the file into memory, so no later read waits on the disk. */
+        fun preload(context: Context) {
+            context.getSharedPreferences(NAME, Context.MODE_PRIVATE).all
+        }
+
+        private const val NAME = "proton_stream_settings"
+        private const val KEY_WIFI_ONLY = "wifi_only"
+        private const val KEY_BACKGROUND_AUDIO = "background_audio"
+        private const val KEY_HARDWARE_DECODING = "hardware_decoding"
+        private const val KEY_CACHE_BUDGET_GIB = "cache_budget_gib"
+        private const val KEY_LIBRARY_SORT = "library_sort"
+        private const val KEY_LIBRARY_GROUPED = "library_grouped"
+        private const val KEY_LIBRARY_FILTER = "library_filter"
+        private const val KEY_NEW_EPISODE_NOTIFICATIONS = "new_episode_notifications"
+        private const val KEY_METADATA_OFFER_DISMISSED = "metadata_offer_dismissed"
     }
 }

android/app/src/main/java/io/narl/protonstream/sync/NewEpisodesWorker.kt

@@ -0,0 +1,136 @@
+package io.narl.protonstream.sync
+
+import android.Manifest
+import android.app.NotificationChannel
+import android.app.NotificationManager
+import android.app.PendingIntent
+import android.content.Context
+import android.content.Intent
+import android.content.pm.PackageManager
+import android.os.Build
+import androidx.core.app.NotificationCompat
+import androidx.core.app.NotificationManagerCompat
+import androidx.work.Constraints
+import androidx.work.CoroutineWorker
+import androidx.work.ExistingPeriodicWorkPolicy
+import androidx.work.NetworkType
+import androidx.work.PeriodicWorkRequestBuilder
+import androidx.work.WorkManager
+import androidx.work.WorkerParameters
+import io.narl.protonstream.MainActivity
+import io.narl.protonstream.R
+import io.narl.protonstream.native.NativeRuntime
+import io.narl.protonstream.settings.SettingsStore
+import uniffi.pstr_android.NewEpisodesRecord
+import java.util.concurrent.TimeUnit
+
+/**
+ * Look at the shares while the app is away, and say when a show gained episodes.
+ *
+ * The app crawls a share it has not looked at for six hours whenever it opens,
+ * which finds a new episode only once someone opens it to look. This runs the
+ * same crawl on WorkManager's schedule instead. It only reports files the
+ * crawl itself found, so a share the app crawled since says nothing twice.
+ */
+class NewEpisodesWorker(
+    appContext: Context,
+    parameters: WorkerParameters,
+) : CoroutineWorker(appContext, parameters) {
+    override suspend fun doWork(): Result {
+        if (!SettingsStore(applicationContext).newEpisodeNotifications) return Result.success()
+        val news = runCatching { NativeRuntime.engine().crawlForNews() }.getOrElse { return Result.retry() }
+        if (news.isNotEmpty()) post(news)
+        return Result.success()
+    }
+
+    private fun post(news: List<NewEpisodesRecord>) {
+        if (
+            Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU &&
+            applicationContext.checkSelfPermission(Manifest.permission.POST_NOTIFICATIONS) !=
+            PackageManager.PERMISSION_GRANTED
+        ) {
+            return
+        }
+        val manager = applicationContext.getSystemService(NotificationManager::class.java)
+        manager.createNotificationChannel(
+            NotificationChannel(CHANNEL_ID, "New episodes", NotificationManager.IMPORTANCE_DEFAULT).apply {
+                description = "A show in your library gained episodes"
+            },
+        )
+        val open = PendingIntent.getActivity(
+            applicationContext,
+            0,
+            Intent(applicationContext, MainActivity::class.java),
+            PendingIntent.FLAG_IMMUTABLE or PendingIntent.FLAG_UPDATE_CURRENT,
+        )
+        val compat = NotificationManagerCompat.from(applicationContext)
+        // One per show, keyed by it, so a second crawl's news for the same show
+        // replaces the first rather than stacking under it.
+        news.forEach { item ->
+            val notification = NotificationCompat.Builder(applicationContext, CHANNEL_ID)
+                .setSmallIcon(R.drawable.ic_notification_stream)
+                .setContentTitle(item.title)
+                .setContentText(describe(item))
+                .setContentIntent(open)
+                .setGroup(GROUP)
+                .setAutoCancel(true)
+                .build()
+            compat.notify(item.titleKey, NOTIFICATION_ID, notification)
+        }
+        if (news.size > 1) {
+            val summary = NotificationCompat.Builder(applicationContext, CHANNEL_ID)
+                .setSmallIcon(R.drawable.ic_notification_stream)
+                .setContentTitle("New episodes")
+                .setContentText(news.joinToString { it.title })
+                .setContentIntent(open)
+                .setGroup(GROUP)
+                .setGroupSummary(true)
+                .setAutoCancel(true)
+                .build()
+            compat.notify(SUMMARY_TAG, NOTIFICATION_ID, summary)
+        }
+    }
+
+    companion object {
+        private const val WORK_NAME = "new-episodes"
+        private const val CHANNEL_ID = "new-episodes"
+        private const val GROUP = "io.narl.protonstream.NEW_EPISODES"
+        private const val SUMMARY_TAG = "new-episodes-summary"
+        private const val NOTIFICATION_ID = 7
+        private const val INTERVAL_HOURS = 6L
+
+        /** What one show's notification says: "S01E04 and 2 more". */
+        fun describe(news: NewEpisodesRecord): String {
+            val more = news.count.toInt() - 1
+            val first = news.first
+            return when {
+                first == null -> if (news.count == 1u) "1 new episode" else "${news.count} new episodes"
+                more == 0 -> "$first is new"
+                more == 1 -> "$first and 1 more are new"
+                else -> "$first and $more more are new"
+            }
+        }
+
+        /**
+         * Keep the periodic look scheduled, or cancel it when the viewer
+         * turned it off. Called on every launch; keeping an existing schedule
+         * means a launch does not push the next look back.
+         */
+        fun schedule(context: Context) {
+            val work = WorkManager.getInstance(context.applicationContext)
+            if (!SettingsStore(context).newEpisodeNotifications) {
+                work.cancelUniqueWork(WORK_NAME)
+                return
+            }
+            val request = PeriodicWorkRequestBuilder<NewEpisodesWorker>(INTERVAL_HOURS, TimeUnit.HOURS)
+                .setConstraints(
+                    Constraints.Builder()
+                        .setRequiredNetworkType(NetworkType.CONNECTED)
+                        .setRequiresBatteryNotLow(true)
+                        .build(),
+                )
+                .build()
+            work.enqueueUniquePeriodicWork(WORK_NAME, ExistingPeriodicWorkPolicy.KEEP, request)
+        }
+    }
+}

android/app/src/main/java/io/narl/protonstream/sync/WatchSyncWorker.kt

@@ -0,0 +1,56 @@
+package io.narl.protonstream.sync
+
+import android.content.Context
+import androidx.work.BackoffPolicy
+import androidx.work.Constraints
+import androidx.work.CoroutineWorker
+import androidx.work.ExistingWorkPolicy
+import androidx.work.NetworkType
+import androidx.work.OneTimeWorkRequestBuilder
+import androidx.work.WorkManager
+import androidx.work.WorkerParameters
+import io.narl.protonstream.native.NativeRuntime
+import uniffi.pstr_android.AccountState
+import java.util.concurrent.TimeUnit
+
+/**
+ * One watch-history sync after the app leaves the screen.
+ *
+ * The model's timer only runs while the app is alive, and Android is free to
+ * kill a process in the background without notice — so the position the
+ * viewer stopped at would wait for the next launch to reach their other
+ * devices. Handed to WorkManager instead, it goes as soon as there is a
+ * network, even if the process is gone by then.
+ */
+class WatchSyncWorker(
+    appContext: Context,
+    parameters: WorkerParameters,
+) : CoroutineWorker(appContext, parameters) {
+    override suspend fun doWork(): Result {
+        val engine = NativeRuntime.engine()
+        return runCatching { engine.syncWatchHistory() }.fold(
+            onSuccess = { Result.success() },
+            onFailure = {
+                // Signed out by the engine — the session ended — is not
+                // something a retry fixes; a dropped connection is.
+                val signedOut = runCatching { engine.accountState() }.getOrNull() == AccountState.SignedOut
+                if (signedOut || runAttemptCount >= MAX_ATTEMPTS) Result.failure() else Result.retry()
+            },
+        )
+    }
+
+    companion object {
+        private const val WORK_NAME = "watch-history-sync"
+        private const val MAX_ATTEMPTS = 3
+
+        /** Replacing: one pending sync covers every position saved before it runs. */
+        fun enqueue(context: Context) {
+            val request = OneTimeWorkRequestBuilder<WatchSyncWorker>()
+                .setConstraints(Constraints.Builder().setRequiredNetworkType(NetworkType.CONNECTED).build())
+                .setBackoffCriteria(BackoffPolicy.EXPONENTIAL, 30, TimeUnit.SECONDS)
+                .build()
+            WorkManager.getInstance(context.applicationContext)
+                .enqueueUniqueWork(WORK_NAME, ExistingWorkPolicy.REPLACE, request)
+        }
+    }
+}

android/app/src/main/java/io/narl/protonstream/ui/AccountUi.kt

@@ -0,0 +1,507 @@
+package io.narl.protonstream.ui
+
+import android.annotation.SuppressLint
+import android.os.Handler
+import android.os.Looper
+import android.webkit.JavascriptInterface
+import android.webkit.WebResourceRequest
+import android.webkit.WebView
+import android.webkit.WebViewClient
+import androidx.activity.compose.BackHandler
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.ArrowBack
+import androidx.compose.material.icons.filled.AccountCircle
+import androidx.compose.material.icons.filled.Close
+import androidx.compose.material.icons.filled.Computer
+import androidx.compose.material.icons.filled.Folder
+import androidx.compose.material.icons.filled.FolderShared
+import androidx.compose.material.icons.filled.InsertDriveFile
+import androidx.compose.material.icons.filled.Logout
+import androidx.compose.material.icons.filled.Movie
+import androidx.compose.material.icons.filled.MoreVert
+import androidx.compose.material.icons.filled.Storage
+import androidx.compose.material.icons.filled.Sync
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.Card
+import androidx.compose.material3.CircularProgressIndicator
+import androidx.compose.material3.DropdownMenu
+import androidx.compose.material3.DropdownMenuItem
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.ListItem
+import androidx.compose.material3.ListItemDefaults
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.Scaffold
+import androidx.compose.material3.Text
+import androidx.compose.material3.TopAppBar
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateListOf
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.text.input.KeyboardType
+import androidx.compose.ui.text.input.PasswordVisualTransformation
+import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.viewinterop.AndroidView
+import androidx.compose.ui.window.Dialog
+import androidx.compose.ui.window.DialogProperties
+import androidx.compose.ui.window.SecureFlagPolicy
+import io.narl.protonstream.native.NativeRuntime
+import io.narl.protonstream.ui.theme.AccentButton
+import io.narl.protonstream.ui.theme.TonalButton
+import uniffi.pstr_android.AccountState
+import uniffi.pstr_android.DriveEntryRecord
+import uniffi.pstr_android.DrivePlaceRecord
+import uniffi.pstr_android.PlaceType
+import uniffi.pstr_android.verificationToken
+
+/** What the account card and its dialogs can ask the model for. */
+internal data class AccountActions(
+    val signIn: (String, String, String?) -> Unit,
+    val submitSecondFactor: (String) -> Unit,
+    val submitMailboxPassword: (String) -> Unit,
+    val cancelSignIn: () -> Unit,
+    val dismissVerification: () -> Unit,
+    val signOut: () -> Unit,
+    val syncNow: () -> Unit,
+    val addFolder: (String, String, String) -> Unit,
+    val onError: (Throwable) -> Unit,
+)
+
+/**
+ * The Proton account, at the top of the shares page: why one would sign in,
+ * or who is signed in and how watch-history sync is doing.
+ */
+@Composable
+internal fun AccountCard(
+    account: AccountUiState,
+    actions: AccountActions,
+    onSignIn: () -> Unit,
+    onBrowse: () -> Unit,
+) {
+    val state = account.state ?: return
+    Card(Modifier.fillMaxWidth().padding(horizontal = 16.dp, vertical = 8.dp)) {
+        if (state is AccountState.SignedIn) {
+            var menu by remember { mutableStateOf(false) }
+            ListItem(
+                headlineContent = { Text(state.username, fontWeight = FontWeight.SemiBold) },
+                supportingContent = { Text(syncLine(account, System.currentTimeMillis())) },
+                leadingContent = {
+                    Icon(Icons.Default.AccountCircle, contentDescription = null, tint = MaterialTheme.colorScheme.primary)
+                },
+                trailingContent = {
+                    Box {
+                        IconButton(onClick = { menu = true }) {
+                            Icon(Icons.Default.MoreVert, contentDescription = "Account actions")
+                        }
+                        DropdownMenu(expanded = menu, onDismissRequest = { menu = false }) {
+                            DropdownMenuItem(
+                                text = { Text("Sync now") },
+                                leadingIcon = { Icon(Icons.Default.Sync, contentDescription = null) },
+                                onClick = { menu = false; actions.syncNow() },
+                            )
+                            DropdownMenuItem(
+                                text = { Text("Sign out") },
+                                leadingIcon = { Icon(Icons.Default.Logout, contentDescription = null) },
+                                onClick = { menu = false; actions.signOut() },
+                            )
+                        }
+                    }
+                },
+                colors = ListItemDefaults.colors(containerColor = Color.Transparent),
+            )
+            TonalButton(
+                onClick = onBrowse,
+                modifier = Modifier.padding(start = 16.dp, end = 16.dp, bottom = 16.dp),
+            ) {
+                Icon(Icons.Default.Folder, contentDescription = null)
+                Text("Add from your Drive", Modifier.padding(start = 8.dp))
+            }
+        } else {
+            Column(Modifier.padding(16.dp), verticalArrangement = Arrangement.spacedBy(8.dp)) {
+                Text("Proton account", style = MaterialTheme.typography.titleMedium)
+                Text(
+                    "Optional. Signed in, your shares, settings and watch history are kept in your own " +
+                        "Drive, so every device shows the same library and resumes where another left off, " +
+                        "and folders of your Drive can join the library.",
+                    style = MaterialTheme.typography.bodyMedium,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                )
+                TonalButton(onClick = onSignIn) { Text("Sign in") }
+            }
+        }
+    }
+}
+
+/** "Synced 3 min ago · 2 from other devices", or why it did not. */
+internal fun syncLine(account: AccountUiState, now: Long): String {
+    account.syncError?.let { return "Did not sync: $it" }
+    val at = account.syncedAt ?: return "Library, settings and watch history sync through your Drive"
+    val minutes = ((now - at).coerceAtLeast(0) / 60_000).toInt()
+    val ago = when {
+        minutes < 1 -> "just now"
+        minutes < 60 -> "$minutes min ago"
+        else -> "${minutes / 60} h ago"
+    }
+    val applied = if (account.applied > 0) " · ${account.applied} from other devices" else ""
+    return "Synced $ago$applied"
+}
+
+/**
+ * Signing in, one step at a time: address and password, then a second-factor
+ * code or the mailbox password if the account has them, with Proton's CAPTCHA
+ * over the top when it asks for one.
+ */
+@Composable
+internal fun SignInDialog(account: AccountUiState, actions: AccountActions, onDismiss: () -> Unit) {
+    var username by remember { mutableStateOf("") }
+    var password by remember { mutableStateOf("") }
+    var code by remember { mutableStateOf("") }
+    var mailbox by remember { mutableStateOf("") }
+    val state = account.state
+    LaunchedEffect(state) {
+        if (state is AccountState.SignedIn) onDismiss()
+    }
+    val dismiss = {
+        if (state == AccountState.SecondFactor || state == AccountState.MailboxPassword) actions.cancelSignIn()
+        onDismiss()
+    }
+    AlertDialog(
+        onDismissRequest = dismiss,
+        properties = DialogProperties(securePolicy = SecureFlagPolicy.SecureOn),
+        title = { Text("Sign in to Proton") },
+        text = {
+            Column(verticalArrangement = Arrangement.spacedBy(8.dp)) {
+                when (state) {
+                    AccountState.SecondFactor -> {
+                        OutlinedTextField(
+                            code,
+                            { code = it },
+                            label = { Text("Code from your authenticator app") },
+                            singleLine = true,
+                            keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.NumberPassword),
+                        )
+                        Text(SECURITY_KEY_NOTE, style = MaterialTheme.typography.bodySmall)
+                    }
+                    AccountState.MailboxPassword -> {
+                        Text(
+                            "This account has a separate mailbox password. It unlocks your files.",
+                            style = MaterialTheme.typography.bodySmall,
+                        )
+                        PasswordField(mailbox, { mailbox = it }, "Mailbox password")
+                    }
+                    else -> {
+                        OutlinedTextField(
+                            username,
+                            { username = it },
+                            label = { Text("Address") },
+                            singleLine = true,
+                            keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Email),
+                        )
+                        PasswordField(password, { password = it }, "Password")
+                    }
+                }
+                account.error?.let { Text(it, color = MaterialTheme.colorScheme.error) }
+                if (account.busy) CircularProgressIndicator(Modifier.padding(top = 4.dp))
+            }
+        },
+        confirmButton = {
+            when (state) {
+                AccountState.SecondFactor -> AccentButton(
+                    onClick = { actions.submitSecondFactor(code.trim()) },
+                    enabled = code.isNotBlank() && !account.busy,
+                ) { Text("Continue") }
+                AccountState.MailboxPassword -> AccentButton(
+                    onClick = { actions.submitMailboxPassword(mailbox) },
+                    enabled = mailbox.isNotEmpty() && !account.busy,
+                ) { Text("Unlock") }
+                else -> AccentButton(
+                    onClick = { actions.signIn(username.trim(), password, null) },
+                    enabled = username.isNotBlank() && password.isNotEmpty() && !account.busy,
+                ) { Text("Sign in") }
+            }
+        },
+        dismissButton = { TonalButton(onClick = dismiss) { Text("Cancel") } },
+    )
+    account.verificationUrl?.let { url ->
+        VerificationDialog(
+            url = url,
+            onToken = { token -> actions.signIn(username.trim(), password, token) },
+            onDismiss = actions.dismissVerification,
+        )
+    }
+}
+
+@Composable
+private fun PasswordField(value: String, onChange: (String) -> Unit, label: String) = OutlinedTextField(
+    value,
+    onChange,
+    label = { Text(label) },
+    singleLine = true,
+    visualTransformation = PasswordVisualTransformation(),
+    keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Password),
+)
+
+/**
+ * Proton's hosted CAPTCHA, which it puts in front of a sign-in it does not
+ * recognise — a new network, a VPN exit.
+ *
+ * In a WebView rather than the browser because the page reports success by
+ * posting a message to its host, not by redirecting: a browser has nowhere to
+ * post it back to. The page targets `window.parent`, which for a top-level
+ * page is the page itself, so a listener on its own window hears it.
+ */
+@SuppressLint("SetJavaScriptEnabled") // The verification page is a script; it does not run without.
+@Composable
+private fun VerificationDialog(url: String, onToken: (String) -> Unit, onDismiss: () -> Unit) {
+    Dialog(onDismissRequest = onDismiss, properties = DialogProperties(usePlatformDefaultWidth = false)) {
+        Card(Modifier.fillMaxWidth().padding(16.dp).height(560.dp)) {
+            Row(verticalAlignment = Alignment.CenterVertically) {
+                Text(
+                    "Confirm you are human",
+                    style = MaterialTheme.typography.titleMedium,
+                    modifier = Modifier.weight(1f).padding(start = 16.dp),
+                )
+                IconButton(onClick = onDismiss) { Icon(Icons.Default.Close, contentDescription = "Cancel") }
+            }
+            AndroidView(
+                modifier = Modifier.fillMaxSize(),
+                factory = { context ->
+                    val main = Handler(Looper.getMainLooper())
+                    var answered = false
+                    WebView(context).apply {
+                        settings.javaScriptEnabled = true
+                        settings.domStorageEnabled = true
+                        addJavascriptInterface(
+                            object {
+                                @JavascriptInterface
+                                fun post(message: String) {
+                                    // Every message the page posts lands here,
+                                    // most of them its own chatter.
+                                    val token = verificationToken(message) ?: return
+                                    main.post {
+                                        if (!answered) {
+                                            answered = true
+                                            onToken(token)
+                                        }
+                                    }
+                                }
+                            },
+                            "pstrVerification",
+                        )
+                        webViewClient = object : WebViewClient() {
+                            override fun onPageStarted(view: WebView, url: String?, favicon: android.graphics.Bitmap?) {
+                                view.evaluateJavascript(VERIFICATION_BRIDGE, null)
+                            }
+
+                            override fun onPageFinished(view: WebView, url: String?) {
+                                view.evaluateJavascript(VERIFICATION_BRIDGE, null)
+                            }
+
+                            // The bridge above is reachable by whatever the
+                            // frame shows, so the frame stays on Proton.
+                            override fun shouldOverrideUrlLoading(view: WebView, request: WebResourceRequest) =
+                                !isProtonPage(request.url.scheme, request.url.host)
+                        }
+                        loadUrl(url)
+                    }
+                },
+            )
+        }
+    }
+}
+
+/**
+ * Security keys need WebAuthn, which the sign-in here does not speak. An account
+ * with nothing else is refused before this form (`AccountStore::sign_in`).
+ */
+private const val SECURITY_KEY_NOTE =
+    "Security keys are not supported here — use the code from your authenticator app."
+
+/** Installed once per page, at start and again at finish in case the first ran too early. */
+private const val VERIFICATION_BRIDGE = """
+if (!window.__pstrVerification) {
+    window.__pstrVerification = true;
+    window.addEventListener('message', function (event) {
+        try {
+            pstrVerification.post(typeof event.data === 'string' ? event.data : JSON.stringify(event.data));
+        } catch (e) {}
+    });
+}
+"""
+
+/** Whether a page is Proton's own, over HTTPS. */
+internal fun isProtonPage(scheme: String?, host: String?): Boolean =
+    scheme == "https" && host != null && (host == "proton.me" || host.endsWith(".proton.me"))
+
+/**
+ * Walk the account's Drive and add a folder of it to the library.
+ *
+ * Full screen, because a Drive is deep and a dialog's height is a few rows of
+ * it. Listings are asked for here rather than through the model: they are
+ * this dialog's alone, and gone when it closes.
+ */
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+internal fun DriveBrowserDialog(
+    actions: AccountActions,
+    onDismiss: () -> Unit,
+) {
+    val trail = remember { mutableStateListOf<Pair<String, DrivePlaceRecord>>() }
+    var places by remember { mutableStateOf<List<DrivePlaceRecord>?>(null) }
+    var entries by remember { mutableStateOf<List<DriveEntryRecord>?>(null) }
+    var error by remember { mutableStateOf<String?>(null) }
+    val current = trail.lastOrNull()?.second
+
+    LaunchedEffect(current) {
+        error = null
+        if (current == null) {
+            if (places == null) {
+                runCatching { NativeRuntime.engine().drivePlaces() }
+                    .onSuccess { places = it }
+                    .onFailure { error = it.message }
+            }
+        } else {
+            entries = null
+            runCatching { NativeRuntime.engine().driveFolder(current.volumeId, current.linkId) }
+                .onSuccess { entries = it }
+                .onFailure { error = it.message }
+        }
+    }
+
+    Dialog(onDismissRequest = onDismiss, properties = DialogProperties(usePlatformDefaultWidth = false)) {
+        BackHandler(enabled = trail.isNotEmpty()) { trail.removeAt(trail.lastIndex) }
+        Scaffold(
+            topBar = {
+                TopAppBar(
+                    title = {
+                        Text(
+                            trail.lastOrNull()?.first ?: "Your Drive",
+                            maxLines = 1,
+                            overflow = TextOverflow.Ellipsis,
+                        )
+                    },
+                    navigationIcon = {
+                        IconButton(onClick = { if (trail.isEmpty()) onDismiss() else trail.removeAt(trail.lastIndex) }) {
+                            Icon(
+                                if (trail.isEmpty()) Icons.Default.Close else Icons.AutoMirrored.Filled.ArrowBack,
+                                contentDescription = if (trail.isEmpty()) "Close" else "Up a folder",
+                            )
+                        }
+                    },
+                )
+            },
+            bottomBar = {
+                // A folder already in the library is refused by the engine,
+                // with a message saying so.
+                val folder = current ?: return@Scaffold
+                Row(Modifier.fillMaxWidth().padding(16.dp), horizontalArrangement = Arrangement.End) {
+                    AccentButton(
+                        onClick = {
+                            actions.addFolder(trail.last().first, folder.volumeId, folder.linkId)
+                            onDismiss()
+                        },
+                    ) { Text("Add this folder") }
+                }
+            },
+        ) { padding ->
+            Box(Modifier.fillMaxSize().padding(padding)) {
+                val loading = error == null && (if (current == null) places == null else entries == null)
+                when {
+                    error != null -> EmptyState("Could not list this", error.orEmpty())
+                    loading -> CircularProgressIndicator(Modifier.align(Alignment.Center))
+                    current == null -> LazyColumn(contentPadding = PaddingValues(vertical = 8.dp)) {
+                        items(places.orEmpty(), key = { "${it.volumeId}/${it.linkId}" }) { place ->
+                            DriveRow(
+                                icon = when (place.kind) {
+                                    PlaceType.MY_FILES -> Icons.Default.Storage
+                                    PlaceType.DEVICE -> Icons.Default.Computer
+                                    PlaceType.SHARED_WITH_ME -> Icons.Default.FolderShared
+                                },
+                                name = place.name,
+                                detail = null,
+                                onClick = { trail.add(place.name to place) },
+                            )
+                        }
+                    }
+                    entries.orEmpty().isEmpty() -> EmptyState("Empty folder", "Nothing to add from here.")
+                    else -> LazyColumn(contentPadding = PaddingValues(vertical = 8.dp)) {
+                        items(entries.orEmpty(), key = { "${it.volumeId}/${it.linkId}" }) { entry ->
+                            DriveRow(
+                                icon = when {
+                                    entry.isFolder -> Icons.Default.Folder
+                                    entry.isVideo -> Icons.Default.Movie
+                                    else -> Icons.Default.InsertDriveFile
+                                },
+                                name = entry.name,
+                                detail = entry.size?.let(::formatBytes),
+                                onClick = if (entry.isFolder) {
+                                    {
+                                        trail.add(
+                                            entry.name to DrivePlaceRecord(
+                                                PlaceType.MY_FILES,
+                                                entry.name,
+                                                entry.volumeId,
+                                                entry.linkId,
+                                            ),
+                                        )
+                                    }
+                                } else {
+                                    null
+                                },
+                            )
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+
+@Composable
+private fun DriveRow(
+    icon: androidx.compose.ui.graphics.vector.ImageVector,
+    name: String,
+    detail: String?,
+    onClick: (() -> Unit)?,
+) {
+    ListItem(
+        headlineContent = { Text(name, maxLines = 2, overflow = TextOverflow.Ellipsis) },
+        supportingContent = detail?.let { { Text(it) } },
+        leadingContent = {
+            Icon(
+                icon,
+                contentDescription = null,
+                tint = if (onClick != null) {
+                    MaterialTheme.colorScheme.primary
+                } else {
+                    MaterialTheme.colorScheme.onSurfaceVariant
+                },
+            )
+        },
+        colors = ListItemDefaults.colors(containerColor = Color.Transparent),
+        modifier = if (onClick != null) Modifier.clickable(onClick = onClick) else Modifier,
+    )
+}

android/app/src/main/java/io/narl/protonstream/ui/AppViewModel.kt

@@ -25,17 +25,42 @@ import kotlinx.coroutines.flow.callbackFlow
 import kotlinx.coroutines.channels.awaitClose
 import kotlinx.coroutines.withContext
 import io.narl.protonstream.native.NativeRuntime
+import io.narl.protonstream.settings.SettingsStore
+import io.narl.protonstream.ui.theme.AppearanceState
+import uniffi.pstr_android.ArrangementRecord
+import uniffi.pstr_android.LibraryFilter
+import uniffi.pstr_android.LibrarySort
 import uniffi.pstr_android.ShareRecord
 import uniffi.pstr_android.TitleRecord
 import uniffi.pstr_android.OfflineRecord
+import uniffi.pstr_android.MatchSummary
 import uniffi.pstr_android.MetadataProvider
 import uniffi.pstr_android.MetadataSettingsRecord
+import uniffi.pstr_android.StorageUsageRecord
+import uniffi.pstr_android.EpisodeRecord
+import uniffi.pstr_android.WatchStateRecord
+import uniffi.pstr_android.AccountState
+import uniffi.pstr_android.SignInOutcome
+import uniffi.pstr_android.SyncRecord
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.isActive
 
 data class AppUiState(
     val loading: Boolean = true,
     val refreshing: Boolean = false,
+    /** A crawl is running, which the banner offers to stop. */
+    val crawling: Boolean = false,
     val query: String = "",
     val titles: List<TitleRecord> = emptyList(),
+    /**
+     * The grid: [titles] ordered, each franchise folded into one tile when
+     * [grouped], and the shelves above it. Null until the bridge has answered,
+     * when the grid falls back to [titles] as they are.
+     */
+    val arrangement: ArrangementRecord? = null,
+    val filter: LibraryFilter = LibraryFilter.ALL,
+    val sort: LibrarySort = LibrarySort.NAME,
+    val grouped: Boolean = true,
     val shares: List<ShareRecord> = emptyList(),
     val offline: List<OfflineRecord> = emptyList(),
     val metadataSettings: MetadataSettingsRecord = MetadataSettingsRecord(
@@ -44,18 +69,102 @@ data class AppUiState(
         language = "en",
         ready = true,
     ),
+    val storage: StorageUsageRecord = StorageUsageRecord(0uL, 0uL, 0uL, 0uL),
     val message: String? = null,
+    /**
+     * What is running in the background right now, said in a banner for as
+     * long as it runs: an add, a crawl, a match, a sync. Without it a
+     * minute-long crawl looked like a tap that did nothing.
+     */
+    val activity: String? = null,
+    /** What Undo on [message] puts back, when the message offers one. */
+    val undo: List<WatchSnapshot>? = null,
+    val account: AccountUiState = AccountUiState(),
 )
 
+/** The Proton account: where a sign-in stands, and how sync is doing. */
+data class AccountUiState(
+    /** Null until the bridge has said. */
+    val state: AccountState? = null,
+    /** A sign-in step is out and not answered yet. */
+    val busy: Boolean = false,
+    /** Why the last sign-in step was refused. */
+    val error: String? = null,
+    /** The CAPTCHA page Proton wants solved before it accepts the sign-in. */
+    val verificationUrl: String? = null,
+    /** When watch history last synced, in epoch milliseconds. */
+    val syncedAt: Long? = null,
+    /** Positions the last sync took from other devices. */
+    val applied: Int = 0,
+    /** Why the last sync failed, until one succeeds. */
+    val syncError: String? = null,
+)
+
+/**
+ * One episode's watch state as it was before a change the viewer can undo.
+ * Null [state] means it had never been played.
+ */
+data class WatchSnapshot(val shareId: String, val linkId: String, val state: WatchStateRecord?)
+
 @OptIn(FlowPreview::class)
 class AppViewModel(context: Context, private val workManager: WorkManager) : ViewModel() {
     private val appContext = context.applicationContext
     private val mutableState = MutableStateFlow(AppUiState())
     private val searchQuery = MutableStateFlow("")
     val state: StateFlow<AppUiState> = mutableState.asStateFlow()
+    /** Launch and coming back both ask; one crawl answers. */
+    private var catchingUp = false
+
+    /**
+     * Every banner line whose work is still running, oldest first. Touched on
+     * the main thread only, as everything in [viewModelScope] is.
+     */
+    private val activities = mutableListOf<Pair<Long, String>>()
+    private var nextActivity = 0L
+
+    /** Crawls running now; main thread only, like [activities]. */
+    private var crawlsRunning = 0
+
+    /** Set by [stopCrawl], so a queue of shares stops rather than going on to the next. */
+    private var crawlStopped = false
 
     init {
-        reload()
+        if (!NativeRuntime.tlsReady) {
+            mutableState.update {
+                it.copy(message = "Certificate verification is unavailable; Proton requests will fail")
+            }
+        }
+        // The arrangement first, so the first grid is drawn the way the viewer
+        // left it rather than A–Z and then re-sorted under them.
+        viewModelScope.launch {
+            val (filter, sort, grouped) = withContext(Dispatchers.IO) {
+                SettingsStore(appContext).run {
+                    Triple(
+                        libraryFilter?.let { name -> LibraryFilter.entries.firstOrNull { it.name == name } },
+                        librarySort?.let { name -> LibrarySort.entries.firstOrNull { it.name == name } },
+                        libraryGrouped,
+                    )
+                }
+            }
+            mutableState.update { it.copy(filter = filter ?: it.filter, sort = sort ?: it.sort, grouped = grouped) }
+            reload()
+        }
+        catchUp()
+        viewModelScope.launch {
+            val account = runCatching { withContext(Dispatchers.IO) { NativeRuntime.engine().accountState() } }
+                .getOrDefault(AccountState.SignedOut)
+            updateAccount { it.copy(state = account) }
+            // While the app is alive, on top of after sign-in and whenever the
+            // player closes. Cheap when nothing changed: one folder listing,
+            // and no upload.
+            while (isActive) {
+                syncWatchHistory()
+                // A sync WatchSyncWorker ran while the app was away may have
+                // brought shares this one has not crawled.
+                catchUp()
+                delay(SYNC_INTERVAL_MS)
+            }
+        }
         viewModelScope.launch {
             searchQuery.debounce(300).distinctUntilChanged().collect { reloadLibrary(it) }
         }
@@ -68,6 +177,29 @@ class AppViewModel(context: Context, private val workManager: WorkManager) : Vie
         }
     }
 
+    /** Sort and fold the library, and keep both for the next launch. */
+    fun arrange(sort: LibrarySort, grouped: Boolean) {
+        mutableState.update { it.copy(sort = sort, grouped = grouped) }
+        viewModelScope.launch {
+            withContext(Dispatchers.IO) {
+                SettingsStore(appContext).apply {
+                    librarySort = sort.name
+                    libraryGrouped = grouped
+                }
+            }
+            reloadLibrary(mutableState.value.query)
+        }
+    }
+
+    /** Narrow the grid to some titles, and keep the choice for the next launch. */
+    fun filter(filter: LibraryFilter) {
+        mutableState.update { it.copy(filter = filter) }
+        viewModelScope.launch {
+            withContext(Dispatchers.IO) { SettingsStore(appContext).libraryFilter = filter.name }
+            reloadLibrary(mutableState.value.query)
+        }
+    }
+
     fun search(query: String) {
         mutableState.update { it.copy(query = query) }
         searchQuery.value = query
@@ -75,23 +207,227 @@ class AppViewModel(context: Context, private val workManager: WorkManager) : Vie
 
     fun refresh() {
         viewModelScope.launch {
-            mutableState.update { it.copy(refreshing = true, message = null) }
+            busy("Refreshing the library…") {
-            runCatching { withContext(Dispatchers.IO) { NativeRuntime.engine().crawl(null) } }
+                mutableState.update { it.copy(message = null) }
-                .onFailure { error -> mutableState.update { it.copy(message = error.message) } }
+                runCatching { crawlShares(null) }
-            mutableState.update { it.copy(refreshing = false) }
+                    .onFailure { error -> mutableState.update { it.copy(message = error.message) } }
-            reload()
+            }
+            reloadNow()
+            matchAfterCrawl()
         }
     }
 
-    fun addShare(name: String, url: String, password: String?) {
+    /**
+     * Look up whatever a crawl brought that has no answer yet: a new show, or
+     * a new episode its stored guide cannot name. When everything already has
+     * one the bridge asks nothing, so this is cheap after every crawl.
+     */
+    private suspend fun matchAfterCrawl() {
+        val settings = mutableState.value.metadataSettings
+        if (settings.enabled && settings.ready) match(force = false, quiet = true)
+    }
+
+    /**
+     * Say [what] in the activity banner while [work] runs.
+     *
+     * The banner shows the newest line still running. Work overlaps — a sync
+     * starts during a crawl and ends after it — so each line is removed by
+     * itself rather than by putting back whatever was showing before, which
+     * once brought back a finished crawl's line and spun it forever.
+     */
+    private suspend fun busy(what: String, work: suspend () -> Unit) {
+        val token = nextActivity++
+        activities += token to what
+        showActivity()
+        try {
+            work()
+        } finally {
+            activities.removeAll { it.first == token }
+            showActivity()
+        }
+    }
+
+    /** Crawl one share, or all with null, with the banner offering Stop meanwhile. */
+    private suspend fun crawlShares(id: String?) {
+        crawlsRunning++
+        mutableState.update { it.copy(crawling = true) }
+        try {
+            withContext(Dispatchers.IO) { NativeRuntime.engine().crawl(id) }
+        } finally {
+            crawlsRunning--
+            mutableState.update { it.copy(crawling = crawlsRunning > 0) }
+        }
+    }
+
+    /**
+     * Stop the crawls running now. Shares already read stay in the library;
+     * the one being read keeps what it had.
+     */
+    fun stopCrawl() {
+        crawlStopped = true
+        viewModelScope.launch(Dispatchers.IO) { NativeRuntime.engine().stopCrawl() }
+    }
+
+    private fun showActivity() {
+        val newest = activities.lastOrNull()?.second
+        mutableState.update { it.copy(activity = newest, refreshing = newest != null) }
+    }
+
+    /**
+     * Recrawl one share rather than the whole library.
+     *
+     * A viewer who has just added files to one link should not have to pay for
+     * a walk of every other one — and a share whose link has expired makes a
+     * whole-library refresh fail, which used to leave no way to refresh the
+     * shares that still work.
+     */
+    fun refreshShare(id: String) {
+        viewModelScope.launch {
+            val name = mutableState.value.shares.firstOrNull { it.id == id }?.name ?: "the share"
+            busy("Reading $name…") {
+                mutableState.update { it.copy(message = null) }
+                runCatching { crawlShares(id) }
+                    .onFailure { error -> mutableState.update { it.copy(message = error.message) } }
+            }
+            reloadNow()
+            matchAfterCrawl()
+        }
+    }
+
+    /**
+     * Run enrichment again.
+     *
+     * With [force] every title is looked up afresh, including ones that already
+     * matched — the way out of a library where a provider's early answers were
+     * wrong, or where a match was made against a provider that has since been
+     * changed.
+     */
+    fun matchTitles(force: Boolean) {
+        viewModelScope.launch { match(force) }
+    }
+
+    /**
+     * With [quiet], a run nobody asked for says nothing when it found nothing
+     * to do.
+     */
+    private suspend fun match(force: Boolean, quiet: Boolean = false) {
+        busy("Looking up titles…") {
+            runCatching { withContext(Dispatchers.IO) { NativeRuntime.engine().matchTitles(force) } }
+                .onSuccess { summary ->
+                    if (!quiet || !summary.isEmpty()) {
+                        mutableState.update { it.copy(message = describe(summary)) }
+                    }
+                }
+                .onFailure { error -> mutableState.update { it.copy(message = error.message) } }
+        }
+        reloadNow()
+    }
+
+    private fun MatchSummary.isEmpty() = matched == 0u && unmatched == 0u && failed == 0u && episodes == 0u
+
+    /**
+     * Add a link, and return why it was refused, if it was.
+     *
+     * The link is opened before anything is stored, so the form can stay up
+     * with the reason under it and a retry is a retry — not "already in the
+     * library" for a share that never opened. Only the new share is crawled:
+     * another share that fails to open must not make this one look broken.
+     */
+    suspend fun addShare(name: String, url: String, password: String?): String? {
+        val share = runCatching {
+            withContext(Dispatchers.IO) {
+                NativeRuntime.engine().addShare(name, url, password?.takeIf(String::isNotBlank))
+            }
+        }.getOrElse { return it.message ?: "That link could not be added" }
+        reload()
+        viewModelScope.launch { crawlAdded(listOf(share.id), announce = true) }
+        return null
+    }
+
+    /**
+     * Crawl shares that are new here — added on this device or by sync — then
+     * match them when enrichment is on.
+     */
+    private suspend fun crawlAdded(ids: List<String>, announce: Boolean) {
+        if (ids.isEmpty()) return
+        val before = mutableState.value.titles.map { it.key }.toSet()
+        val failed = mutableListOf<String>()
+        crawlStopped = false
+        for (id in ids) {
+            if (crawlStopped) break
+            val name = mutableState.value.shares.firstOrNull { it.id == id }?.name ?: "the new share"
+            busy("Reading $name…") {
+                runCatching { crawlShares(id) }
+                    .onFailure { failed += "$name: ${it.message}" }
+            }
+        }
+        reloadNow()
+        // A catch-up is the app's doing, not the viewer's: a failure goes on
+        // the share's row rather than in their face, and only news is said.
+        if (failed.isNotEmpty() && announce) {
+            mutableState.update { it.copy(message = failed.joinToString("\n")) }
+            return
+        }
+        matchAfterCrawl()
+        if (announce) {
+            val added = (mutableState.value.titles.map { it.key }.toSet() - before).size
+            mutableState.update { it.copy(message = if (added == 1) "1 title added" else "$added titles added") }
+        } else {
+            val files = mutableState.value.shares.filter { it.id in ids }.sumOf { it.crawlAdded ?: 0uL }
+            if (files > 0uL) {
+                mutableState.update { it.copy(message = if (files == 1uL) "1 new file" else "$files new files") }
+            }
+        }
+    }
+
+    /**
+     * Crawl shares due a look: ones the catalog has nothing of — brought by a
+     * sync that ran in [io.narl.protonstream.sync.WatchSyncWorker], or an add
+     * whose crawl never finished — and ones not crawled for six hours, so new
+     * episodes turn up without a pull to refresh.
+     */
+    fun catchUp() {
+        if (catchingUp) return
+        catchingUp = true
+        viewModelScope.launch {
+            try {
+                val ids = runCatching { withContext(Dispatchers.IO) { NativeRuntime.engine().uncrawledShares() } }
+                    .getOrDefault(emptyList())
+                crawlAdded(ids, announce = false)
+            } finally {
+                catchingUp = false
+            }
+        }
+    }
+
+    /**
+     * Re-supply the link behind a share whose stored secret cannot be read.
+     *
+     * The Keystore key is invalidated by a lockscreen change or a device
+     * restore, and after that every open of every share fails — including the
+     * read inside "remove this share", so the obvious way out is closed too.
+     * Re-entering the link rewrites the secret and leaves the catalog and the
+     * offline files alone.
+     */
+    fun repairShare(id: String, url: String, password: String?) {
         viewModelScope.launch {
             runCatching {
                 withContext(Dispatchers.IO) {
                     val engine = NativeRuntime.engine()
-                    engine.addShare(name, url, password?.takeIf(String::isNotBlank))
+                    engine.repairShare(id, url, password?.takeIf(String::isNotBlank))
-                    engine.crawl(null)
+                    engine.crawl(id)
                 }
-            }.onFailure { error -> mutableState.update { it.copy(message = error.message) } }
+            }.onFailure(::reportError)
+            reloadNow()
+            matchAfterCrawl()
+        }
+    }
+
+    /** Call a share something else. The library, history and downloads stay. */
+    fun renameShare(id: String, name: String) {
+        viewModelScope.launch {
+            runCatching { withContext(Dispatchers.IO) { NativeRuntime.engine().renameShare(id, name) } }
+                .onFailure(::reportError)
             reload()
         }
     }
@@ -117,30 +453,312 @@ class AppViewModel(context: Context, private val workManager: WorkManager) : Vie
         }
     }
 
-    fun dismissMessage() = mutableState.update { it.copy(message = null) }
+    fun dismissMessage() = mutableState.update { it.copy(message = null, undo = null) }
 
-    fun reportError(error: Throwable) {
+    private fun updateAccount(change: (AccountUiState) -> AccountUiState) =
-        mutableState.update { it.copy(message = error.message ?: "Unexpected error") }
+        mutableState.update { it.copy(account = change(it.account)) }
+
+    /**
+     * Start signing in, or start again with [verificationToken] once the
+     * CAPTCHA from a first try is solved.
+     */
+    fun signIn(username: String, password: String, verificationToken: String? = null) =
+        signInStep { engine -> engine.signIn(username, password, verificationToken) }
+
+    fun submitSecondFactor(code: String) = signInStep { engine -> engine.submitSecondFactor(code) }
+
+    fun submitMailboxPassword(password: String) =
+        signInStep(keepStepOnFailure = true) { engine -> engine.submitMailboxPassword(password) }
+
+    fun cancelSignIn() {
+        updateAccount { AccountUiState(state = AccountState.SignedOut) }
+        viewModelScope.launch { runCatching { NativeRuntime.engine().cancelSignIn() } }
     }
 
-    fun saveMetadataSettings(enabled: Boolean, provider: MetadataProvider, language: String, apiKey: String) {
+    /** The CAPTCHA page closed without a token. */
+    fun dismissVerification() = updateAccount { it.copy(verificationUrl = null, busy = false) }
+
+    private fun signInStep(
+        keepStepOnFailure: Boolean = false,
+        step: suspend (uniffi.pstr_android.AndroidEngine) -> SignInOutcome,
+    ) {
+        updateAccount { it.copy(busy = true, error = null, verificationUrl = null) }
+        viewModelScope.launch {
+            runCatching { withContext(Dispatchers.IO) { step(NativeRuntime.engine()) } }
+                .onSuccess { outcome ->
+                    when (outcome) {
+                        is SignInOutcome.Done -> {
+                            updateAccount {
+                                AccountUiState(state = AccountState.SignedIn(outcome.username))
+                            }
+                            mutableState.update { it.copy(message = "Signed in as ${outcome.username}") }
+                            syncWatchHistory()
+                            reload()
+                        }
+                        SignInOutcome.SecondFactor ->
+                            updateAccount { it.copy(state = AccountState.SecondFactor, busy = false) }
+                        SignInOutcome.MailboxPassword ->
+                            updateAccount { it.copy(state = AccountState.MailboxPassword, busy = false) }
+                        is SignInOutcome.HumanVerification ->
+                            updateAccount { it.copy(verificationUrl = outcome.url) }
+                    }
+                }
+                .onFailure { error ->
+                    updateAccount {
+                        it.copy(
+                            busy = false,
+                            error = error.message ?: "Sign-in failed",
+                            // A refused code spends the half-made session.
+                            state = if (keepStepOnFailure) it.state else AccountState.SignedOut,
+                        )
+                    }
+                }
+        }
+    }
+
+    fun signOut() {
+        viewModelScope.launch {
+            runCatching { withContext(Dispatchers.IO) { NativeRuntime.engine().signOut() } }
+                .onFailure(::reportError)
+            updateAccount { AccountUiState(state = AccountState.SignedOut) }
+            reload()
+        }
+    }
+
+    /** Sync now, from a tap: says so when it is done. */
+    fun syncNow() {
+        viewModelScope.launch {
+            if (syncWatchHistory()) {
+                val applied = mutableState.value.account.applied
+                mutableState.update {
+                    it.copy(
+                        message = if (applied > 0) {
+                            "Watch history synced, $applied from other devices"
+                        } else {
+                            "Watch history is up to date"
+                        },
+                    )
+                }
+            }
+        }
+    }
+
+    /**
+     * Pull other devices' positions in and push this one's out. Quiet: it runs
+     * on a timer, and a failure is shown on the account card rather than as a
+     * snackbar every five minutes of an offline evening. Returns whether it
+     * synced.
+     */
+    private suspend fun syncWatchHistory(): Boolean {
+        if (mutableState.value.account.state !is AccountState.SignedIn) return false
+        return runCatching { withContext(Dispatchers.IO) { NativeRuntime.engine().syncWatchHistory() } }
+            .fold(
+                onSuccess = { report ->
+                    if (report == null) return false
+                    updateAccount {
+                        it.copy(
+                            syncedAt = System.currentTimeMillis(),
+                            applied = report.applied.toInt(),
+                            syncError = null,
+                        )
+                    }
+                    takeSynced(report)
+                    true
+                },
+                onFailure = { error ->
+                    val state = runCatching { NativeRuntime.engine().accountState() }.getOrNull()
+                    updateAccount { it.copy(state = state ?: it.state, syncError = error.message) }
+                    // Signed out by the engine: the session ended, and that is
+                    // worth interrupting for, unlike a dropped connection.
+                    if (state == AccountState.SignedOut) reportError(error)
+                    false
+                },
+            )
+    }
+
+    /**
+     * What another device changed: its shares crawled or dropped here, its
+     * settings repainted.
+     */
+    private suspend fun takeSynced(report: SyncRecord) {
+        if (report.sharesRemoved.isNotEmpty()) {
+            withContext(Dispatchers.IO) {
+                val downloads = DownloadStateStore(appContext)
+                report.sharesRemoved.forEach { id ->
+                    workManager.cancelAllWorkByTag(DownloadCoordinator.shareTag(id)).result.get()
+                    downloads.removeShare(id)
+                }
+            }
+        }
+        if (report.settingsChanged) AppearanceState.reload()
+        if (report.applied > 0u || report.titles > 0u || report.settingsChanged || report.sharesRemoved.isNotEmpty()) {
+            reloadNow()
+        }
+        if (report.sharesAdded.isNotEmpty()) {
+            crawlAdded(report.sharesAdded, announce = false)
+            val count = report.sharesAdded.size
+            mutableState.update {
+                it.copy(message = if (count == 1) "A share arrived from another device" else "$count shares arrived from other devices")
+            }
+        }
+    }
+
+    /** After the player closes: where it stopped is what another device wants next. */
+    fun playerClosed() {
+        reload()
+        viewModelScope.launch { syncWatchHistory() }
+    }
+
+    fun addAccountFolder(name: String, volumeId: String, linkId: String) {
+        viewModelScope.launch {
+            runCatching {
+                withContext(Dispatchers.IO) { NativeRuntime.engine().addAccountFolder(name, volumeId, linkId) }
+            }.onSuccess { share ->
+                reload()
+                crawlAdded(listOf(share.id), announce = true)
+            }.onFailure(::reportError)
+        }
+    }
+
+    /**
+     * Every episode of a title watched or unwatched, with an Undo: a whole
+     * title's positions are what this throws away, and a mis-tap on a tile's
+     * menu should not cost them.
+     */
+    fun setTitleWatched(title: TitleRecord, watched: Boolean) =
+        markEpisodes(title.seasons.flatMap { it.episodes }, watched, title.displayName)
+
+    /**
+     * Some episodes seen or unseen — a season, or a whole title — with an
+     * Undo; [what] names them in the message.
+     */
+    fun markEpisodes(episodes: List<EpisodeRecord>, watched: Boolean, what: String) {
+        changeWatch(
+            episodes.filter { it.watched != watched },
+            "$what marked ${if (watched) "watched" else "unwatched"}",
+        ) { engine, episode, before ->
+            val duration = before?.durationSecs
+            engine.saveWatchState(
+                episode.shareId,
+                episode.linkId,
+                if (watched) duration ?: 0.0 else 0.0,
+                duration,
+                watched,
+            )
+        }
+    }
+
+    /**
+     * Off Continue watching by forgetting where the episode stopped — what the
+     * desktop does — with an Undo that puts the position back.
+     */
+    fun forgetPosition(title: TitleRecord, episode: EpisodeRecord) {
+        changeWatch(
+            listOf(episode),
+            "${title.displayName} removed from Continue watching",
+        ) { engine, target, before ->
+            engine.saveWatchState(target.shareId, target.linkId, 0.0, before?.durationSecs, false)
+        }
+    }
+
+    /**
+     * Off the history page: the position and the watched mark both go, which
+     * is "never played", with an Undo.
+     */
+    fun removeFromHistory(title: TitleRecord, episode: EpisodeRecord) {
+        changeWatch(
+            listOf(episode),
+            "${episode.label} of ${title.displayName} removed from history",
+        ) { engine, target, before ->
+            engine.saveWatchState(target.shareId, target.linkId, 0.0, before?.durationSecs, false)
+        }
+    }
+
+    /** Put back what the last undoable change replaced. */
+    fun undo() {
+        val snapshots = mutableState.value.undo ?: return
+        mutableState.update { it.copy(message = null, undo = null) }
         viewModelScope.launch {
             runCatching {
                 withContext(Dispatchers.IO) {
                     val engine = NativeRuntime.engine()
-                    if (provider == MetadataProvider.TMDB && apiKey.isNotBlank()) {
+                    snapshots.forEach { snapshot ->
-                        engine.setMetadataApiKey(provider, apiKey)
+                        engine.restoreWatchState(snapshot.shareId, snapshot.linkId, snapshot.state)
                     }
-                    engine.setMetadataSettings(MetadataSettingsRecord(enabled, provider, language, true))
-                    if (enabled) engine.matchTitles(false)
                 }
             }.onFailure(::reportError)
             reload()
         }
     }
 
+    private fun changeWatch(
+        episodes: List<EpisodeRecord>,
+        message: String,
+        change: (uniffi.pstr_android.AndroidEngine, EpisodeRecord, WatchStateRecord?) -> Unit,
+    ) {
+        viewModelScope.launch {
+            runCatching {
+                withContext(Dispatchers.IO) {
+                    val engine = NativeRuntime.engine()
+                    episodes.map { episode ->
+                        val before = engine.watchState(episode.shareId, episode.linkId)
+                        change(engine, episode, before)
+                        WatchSnapshot(episode.shareId, episode.linkId, before)
+                    }
+                }
+            }.onSuccess { snapshots ->
+                mutableState.update { it.copy(message = message, undo = snapshots) }
+            }.onFailure(::reportError)
+            reload()
+        }
+    }
+
+    fun reportError(error: Throwable) {
+        mutableState.update { it.copy(message = error.message ?: "Unexpected error") }
+    }
+
+    /**
+     * Store the enrichment settings, and return why not, if they were not.
+     *
+     * The page shows the new settings as soon as they are stored; the match
+     * run that follows can take minutes and says so in the activity banner.
+     */
+    suspend fun saveMetadataSettings(enabled: Boolean, provider: MetadataProvider, language: String, apiKey: String): String? {
+        val stored = runCatching {
+            withContext(Dispatchers.IO) {
+                val engine = NativeRuntime.engine()
+                if (provider == MetadataProvider.TMDB && apiKey.isNotBlank()) {
+                    engine.setMetadataApiKey(provider, apiKey)
+                }
+                engine.setMetadataSettings(MetadataSettingsRecord(enabled, provider, language, true))
+                engine.metadataSettings()
+            }
+        }.getOrElse { return it.message ?: "The settings could not be saved" }
+        mutableState.update { it.copy(metadataSettings = stored) }
+        reloadNow()
+        if (enabled) viewModelScope.launch { match(force = false) }
+        return null
+    }
+
     fun reloadAfterMetadataChange() = reload()
 
+    /**
+     * What an enrichment pass did, in one line.
+     *
+     * Failures are reported even when most titles matched: a run that quietly
+     * dropped a third of the library is the case this counting exists for.
+     */
+    private fun describe(summary: MatchSummary): String {
+        if (summary.matched == 0u && summary.unmatched == 0u && summary.failed == 0u) {
+            return "Everything is already matched"
+        }
+        val parts = mutableListOf("${summary.matched} matched")
+        if (summary.unmatched > 0u) parts += "${summary.unmatched} not found"
+        if (summary.episodes > 0u) parts += "${summary.episodes} episodes named"
+        if (summary.failed > 0u) parts += "${summary.failed} failed"
+        return parts.joinToString(", ")
+    }
+
     fun removeOffline(file: OfflineRecord) {
         viewModelScope.launch {
             runCatching {
@@ -170,38 +788,120 @@ class AppViewModel(context: Context, private val workManager: WorkManager) : Vie
         }
     }
 
-    private fun reload() {
+    /**
+     * Persist where an episode was left.
+     *
+     * The player calls this while it is still up and once more as it leaves, so
+     * it runs on the ViewModel's scope rather than the screen's — a save issued
+     * on the way out must not be cancelled by the screen going away.
+     */
+    fun saveProgress(episode: EpisodeRecord, position: Double, duration: Double, watched: Boolean) {
         viewModelScope.launch {
             runCatching {
                 withContext(Dispatchers.IO) {
-                    val engine = NativeRuntime.engine()
+                    NativeRuntime.engine().saveWatchState(
-                    Reloaded(
+                        episode.shareId,
-                        engine.shares(),
+                        episode.linkId,
-                        engine.library(mutableState.value.query.takeIf(String::isNotBlank)),
+                        position.coerceIn(0.0, duration),
-                        engine.offlineFiles(),
+                        duration,
-                        engine.metadataSettings(),
+                        watched,
                     )
                 }
-            }.onSuccess { result ->
+            }.onFailure(::reportError)
-                    mutableState.update { it.copy(
-                        loading = false,
-                        shares = result.shares,
-                        titles = result.titles,
-                        offline = result.offline,
-                        metadataSettings = result.metadataSettings,
-                    ) }
-                }
-                .onFailure { error ->
-                    mutableState.update { it.copy(loading = false, message = error.message) }
-                }
         }
     }
 
-    private suspend fun reloadLibrary(query: String) {
+    /**
+     * Mark an episode seen, or unseen, without playing it.
+     *
+     * Unwatching rewinds, matching the desktop client: an episode marked unseen
+     * that kept its position would come straight back as "resume at 19:04",
+     * which is not what the viewer asked for. Marking one seen puts the position
+     * at its duration where one is known, so the progress bar agrees with the
+     * tick.
+     */
+    /** One episode's tick, with the same Undo a season's has. */
+    fun setWatched(episode: EpisodeRecord, watched: Boolean) = markEpisodes(listOf(episode), watched, episode.label)
+
+    fun removeAllOffline() {
+        viewModelScope.launch {
+            runCatching {
+                withContext(Dispatchers.IO) {
+                    workManager.cancelAllWorkByTag(DownloadCoordinator.TAG).result.get()
+                    NativeRuntime.engine().removeAllOffline()
+                    DownloadStateStore(appContext).clear()
+                }
+            }.onFailure(::reportError)
+            reload()
+        }
+    }
+
+    fun clearBlockCache() {
+        viewModelScope.launch {
+            runCatching {
+                withContext(Dispatchers.IO) { NativeRuntime.engine().clearBlockCache() }
+            }.onSuccess { reclaimed ->
+                mutableState.update { it.copy(message = "Reclaimed ${formatBytes(reclaimed)} of cache") }
+            }.onFailure(::reportError)
+            reload()
+        }
+    }
+
+    private fun reload() {
+        viewModelScope.launch { reloadNow() }
+    }
+
+    /** [reload], for a caller that goes on to read what it loaded. */
+    private suspend fun reloadNow() {
         runCatching {
-            withContext(Dispatchers.IO) { NativeRuntime.engine().library(query.takeIf(String::isNotBlank)) }
+            withContext(Dispatchers.IO) {
-        }.onSuccess { titles -> mutableState.update { it.copy(titles = titles) } }
+                val engine = NativeRuntime.engine()
-            .onFailure { error -> mutableState.update { it.copy(message = error.message) } }
+                // Here rather than inside `library()`, which is read-only
+                // and cached: a full reload is the one place that has
+                // already paid for a walk of the offline files.
+                engine.pruneOfflineFiles()
+                val current = mutableState.value
+                val query = current.query.takeIf(String::isNotBlank)
+                Reloaded(
+                    engine.shares(),
+                    engine.library(query),
+                    engine.arrangement(query, current.filter, current.sort, current.grouped),
+                    engine.offlineFiles(),
+                    engine.metadataSettings(),
+                    engine.storageUsage(),
+                )
+            }
+        }.onSuccess { result ->
+                mutableState.update { it.copy(
+                    loading = false,
+                    shares = result.shares,
+                    titles = result.titles,
+                    arrangement = result.arrangement,
+                    offline = result.offline,
+                    metadataSettings = result.metadataSettings,
+                    storage = result.storage,
+                ) }
+            }
+            .onFailure { error ->
+                mutableState.update { it.copy(loading = false, message = error.message) }
+            }
+    }
+
+    private suspend fun reloadLibrary(query: String) {
+        val current = mutableState.value
+        runCatching {
+            withContext(Dispatchers.IO) {
+                val engine = NativeRuntime.engine()
+                val search = query.takeIf(String::isNotBlank)
+                engine.library(search) to engine.arrangement(search, current.filter, current.sort, current.grouped)
+            }
+        }.onSuccess { (titles, arrangement) ->
+            mutableState.update { it.copy(titles = titles, arrangement = arrangement) }
+        }.onFailure { error -> mutableState.update { it.copy(message = error.message) } }
+    }
+
+    private companion object {
+        const val SYNC_INTERVAL_MS = 5 * 60 * 1000L
     }
 
     class Factory(private val context: Context, private val workManager: WorkManager) : ViewModelProvider.Factory {
@@ -213,8 +913,10 @@ class AppViewModel(context: Context, private val workManager: WorkManager) : Vie
 private data class Reloaded(
     val shares: List<ShareRecord>,
     val titles: List<TitleRecord>,
+    val arrangement: ArrangementRecord,
     val offline: List<OfflineRecord>,
     val metadataSettings: MetadataSettingsRecord,
+    val storage: StorageUsageRecord,
 )
 
 private fun WorkManager.workInfosByTagFlow(tag: String) = callbackFlow {

android/app/src/main/java/io/narl/protonstream/ui/Common.kt

@@ -0,0 +1,240 @@
+package io.narl.protonstream.ui
+
+import android.net.ConnectivityManager
+import androidx.compose.animation.AnimatedVisibilityScope
+import androidx.compose.animation.ExperimentalSharedTransitionApi
+import androidx.compose.animation.SharedTransitionScope
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.RowScope
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.padding
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.material3.TopAppBar
+import androidx.compose.material3.TopAppBarColors
+import androidx.compose.material3.TopAppBarDefaults
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.runtime.staticCompositionLocalOf
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.input.nestedscroll.nestedScroll
+import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.unit.dp
+import io.narl.protonstream.download.DownloadCoordinator
+import io.narl.protonstream.download.RetainedDownload
+import io.narl.protonstream.settings.SettingsStore
+import io.narl.protonstream.ui.theme.AccentButton
+import io.narl.protonstream.ui.theme.TonalButton
+import uniffi.pstr_android.EpisodeRecord
+
+/**
+ * A tab's page: its own name in an app bar, over whatever the page holds.
+ *
+ * One bar for the whole app said "proton-stream" on every page, which is a band
+ * of height spent naming the app the viewer is already in. The bar draws under
+ * the status bar itself, which is why the shell hands pages no top padding;
+ * [content] gets the rest of [padding] (the navigation bar and the mini
+ * transport) to apply as it scrolls.
+ */
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+internal fun TabPage(
+    title: String,
+    padding: PaddingValues,
+    navigationIcon: @Composable () -> Unit = {},
+    actions: @Composable RowScope.() -> Unit = {},
+    content: @Composable (PaddingValues) -> Unit,
+) {
+    // Pinned: the bar stays, and takes the container tint once the page has
+    // scrolled under it, so the edge between the two is still visible.
+    val scroll = TopAppBarDefaults.pinnedScrollBehavior()
+    Column(Modifier.fillMaxSize().nestedScroll(scroll.nestedScrollConnection)) {
+        TopAppBar(
+            title = { Text(title) },
+            navigationIcon = navigationIcon,
+            actions = actions,
+            colors = pageBarColors(),
+            scrollBehavior = scroll,
+        )
+        Box(Modifier.weight(1f)) { content(padding) }
+    }
+}
+
+/**
+ * The page's own background until something scrolls under the bar, then the
+ * container tint. A bar in `surface` from the start read as a band across the
+ * top of a page drawn in `background`.
+ */
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+internal fun pageBarColors(): TopAppBarColors = TopAppBarDefaults.topAppBarColors(
+    containerColor = MaterialTheme.colorScheme.background,
+    scrolledContainerColor = MaterialTheme.colorScheme.surfaceContainer,
+)
+
+/**
+ * The shared-element scopes the library-to-title switch runs in, or null where
+ * there is none — the two-pane layout, a screenshot, a preview. Locals rather
+ * than parameters, because the poster that animates is three calls deep in the
+ * grid and nothing between needs to know.
+ */
+@OptIn(ExperimentalSharedTransitionApi::class)
+internal val LocalSharedTransition = staticCompositionLocalOf<SharedTransitionScope?> { null }
+internal val LocalPaneVisibility = staticCompositionLocalOf<AnimatedVisibilityScope?> { null }
+
+/**
+ * A title's art as one element across the switch: the poster tapped in the
+ * grid grows into the backdrop of the page it opens, and shrinks back on the
+ * way out, so the page is visibly *that* title's rather than a new screen.
+ */
+@OptIn(ExperimentalSharedTransitionApi::class)
+@Composable
+internal fun Modifier.sharedArt(key: String): Modifier {
+    val transition = LocalSharedTransition.current ?: return this
+    val visibility = LocalPaneVisibility.current ?: return this
+    return with(transition) {
+        this@sharedArt.sharedBounds(rememberSharedContentState("art/$key"), visibility)
+    }
+}
+
+@Composable
+internal fun EmptyState(title: String, body: String, action: Pair<String, () -> Unit>? = null) {
+    Box(Modifier.fillMaxSize(), contentAlignment = Alignment.Center) {
+        Column(Modifier.padding(horizontal = 32.dp), horizontalAlignment = Alignment.CenterHorizontally) {
+            Text(title, style = MaterialTheme.typography.titleMedium, textAlign = TextAlign.Center)
+            Text(
+                body,
+                style = MaterialTheme.typography.bodyMedium,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+                textAlign = TextAlign.Center,
+                modifier = Modifier.padding(top = 4.dp),
+            )
+            action?.let { (label, onClick) ->
+                AccentButton(onClick = onClick, modifier = Modifier.padding(top = 16.dp)) { Text(label) }
+            }
+        }
+    }
+}
+
+/**
+ * Where Play on a title lands: what Continue watching offers
+ * ([TitleRecord.continueIndex]), else the most recently played part-watched
+ * episode, else the first unwatched one, else the first — the desktop's
+ * `next_up`.
+ */
+internal fun nextUpIndex(playlist: List<EpisodeRecord>, continueIndex: UInt? = null): Int =
+    continueIndex?.toInt()?.takeIf { it in playlist.indices }
+        ?: playlist.withIndex().filter { it.value.resumeAt != null }.maxByOrNull { it.value.lastPlayed }?.index
+        ?: playlist.indexOfFirst { !it.watched }.takeIf { it >= 0 }
+        ?: 0
+
+internal fun formatBytes(bytes: ULong): String {
+    val value = bytes.toDouble()
+    return when {
+        value >= 1024 * 1024 * 1024 -> "%.1f GiB".format(value / (1024 * 1024 * 1024))
+        value >= 1024 * 1024 -> "%.1f MiB".format(value / (1024 * 1024))
+        value >= 1024 -> "%.1f KiB".format(value / 1024)
+        else -> "$bytes bytes"
+    }
+}
+
+/**
+ * Download episodes, asking first when it is more than one: a season or a
+ * show is tens of gigabytes, and one tap should not fill a phone. The
+ * question says how many and how big. Call it in composition; it draws the
+ * dialog where it is called and returns what starts the download.
+ */
+@Composable
+internal fun rememberDownload(): (List<EpisodeRecord>, String) -> Unit {
+    val context = LocalContext.current
+    var asking by remember { mutableStateOf<Pair<List<EpisodeRecord>, String>?>(null) }
+    asking?.let { (episodes, what) ->
+        val bytes = episodes.sumOf { it.size ?: 0uL }
+        AlertDialog(
+            onDismissRequest = { asking = null },
+            title = { Text("Download ${episodes.size} episodes of $what?") },
+            text = {
+                Text(
+                    "They are kept on this device for watching without a connection" +
+                        (if (bytes > 0uL) " — about ${formatBytes(bytes)}" else "") +
+                        ". Delete them from Downloads.",
+                )
+            },
+            confirmButton = {
+                AccentButton(onClick = {
+                    asking = null
+                    DownloadCoordinator.enqueue(context, episodes)
+                }) { Text("Download") }
+            },
+            dismissButton = { TonalButton(onClick = { asking = null }) { Text("Cancel") } },
+        )
+    }
+    return remember(context) {
+        { episodes, what ->
+            val wanted = episodes.filterNot(EpisodeRecord::offline)
+            if (wanted.size > 1) asking = wanted to what else DownloadCoordinator.enqueue(context, wanted)
+        }
+    }
+}
+
+/**
+ * One line under a download that has not finished: "Running · 120.0 MiB of
+ * 1.2 GiB · 2.4 MiB/s", or "Queued" while it waits for a slot — or, given a
+ * [waitingFor], what it is really waiting on.
+ */
+internal fun downloadStatusLine(download: RetainedDownload, waitingFor: String? = null): String = listOfNotNull(
+    waitingFor?.takeIf { download.status == RetainedDownload.STATUS_QUEUED }
+        ?: download.status.replaceFirstChar { it.uppercase() },
+    download.total.takeIf { it > 0L && download.downloaded > 0L }?.let {
+        "${formatBytes(download.downloaded.toULong())} of ${formatBytes(it.toULong())}"
+    },
+    download.bytesPerSecond
+        .takeIf { it > 0L && download.status == RetainedDownload.STATUS_RUNNING }
+        ?.let { "${formatBytes(it.toULong())}/s" },
+).joinToString(" · ")
+
+/**
+ * Why a queued download is not running, when it is not merely a free slot:
+ * WorkManager holds a Wi-Fi-only download back on mobile data without a word,
+ * and "Queued" for an hour on the bus reads as stuck. Re-read whenever [key]
+ * changes — the download's own updates are the clock.
+ */
+@Composable
+internal fun rememberQueueReason(key: Any?): String? {
+    val context = LocalContext.current
+    return remember(key) {
+        val network = context.getSystemService(ConnectivityManager::class.java)
+        when {
+            network?.activeNetwork == null -> "Waiting for a connection"
+            SettingsStore(context).wifiOnly && network.isActiveNetworkMetered -> "Waiting for Wi-Fi"
+            else -> null
+        }
+    }
+}
+
+/**
+ * What an episode row is headed with: "1. Mother and Children".
+ *
+ * The provider's name for the episode, else the name the filename gave it,
+ * else "Episode 1". The bare filename only when none of those exist — a column
+ * of `[Group] Show - S01E01.mkv` is forty rows that differ in two characters.
+ */
+internal fun EpisodeRecord.heading(position: Int): String {
+    val named = providerName ?: detail.takeIf { it != name }
+    val number = number?.toInt()
+    return when {
+        named != null && number != null -> "$number. $named"
+        named != null -> named
+        number != null -> "Episode $number"
+        else -> name.substringBeforeLast('.').ifBlank { "Episode ${position + 1}" }
+    }
+}

android/app/src/main/java/io/narl/protonstream/ui/DownloadsScreen.kt

@@ -0,0 +1,261 @@
+package io.narl.protonstream.ui
+
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.aspectRatio
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Close
+import androidx.compose.material.icons.filled.Pause
+import androidx.compose.material.icons.filled.PlayArrow
+import androidx.compose.material.icons.outlined.Delete
+import androidx.compose.material.icons.outlined.Info
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.ListItem
+import androidx.compose.material3.ListItemDefaults
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.livedata.observeAsState
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.ui.unit.dp
+import androidx.work.WorkManager
+import io.narl.protonstream.download.DownloadCoordinator
+import io.narl.protonstream.download.DownloadStateStore
+import io.narl.protonstream.download.RetainedDownload
+import io.narl.protonstream.ui.theme.DangerButton
+import io.narl.protonstream.ui.theme.AccentProgress
+import io.narl.protonstream.ui.theme.TonalButton
+import uniffi.pstr_android.OfflineRecord
+import uniffi.pstr_android.SeasonRecord
+import uniffi.pstr_android.TitleRecord
+
+/** One show's saved episodes, and the show itself where the library has it. */
+private data class OfflineGroup(val name: String, val title: TitleRecord?, val files: List<OfflineRecord>)
+
+@Composable
+internal fun DownloadsScreen(
+    state: AppUiState,
+    onRemove: (OfflineRecord) -> Unit,
+    onPause: (RetainedDownload) -> Unit,
+    onResume: (RetainedDownload) -> Unit,
+    onDeletePartial: (RetainedDownload) -> Unit,
+    padding: PaddingValues,
+    onPlay: (TitleRecord, Int) -> Unit = { _, _ -> },
+    onOpen: (TitleRecord) -> Unit = {},
+) {
+    val context = LocalContext.current
+    val work = WorkManager.getInstance(context).getWorkInfosByTagLiveData(DownloadCoordinator.TAG)
+    val downloads by work.observeAsState(emptyList())
+    // Reading retained metadata on every WorkInfo transition also hydrates
+    // paused/failed/cancelled entries after WorkManager history is pruned.
+    val retained = remember(downloads) { DownloadStateStore(context).records() }
+    // Which show each saved file is from. The offline record knows its episode
+    // but not its show, and the library is the only thing that does.
+    val groups = remember(state.offline, state.titles) {
+        val shows = state.titles.flatMap { title ->
+            title.seasons.flatMap(SeasonRecord::episodes).map { "${it.shareId}/${it.linkId}" to title }
+        }.toMap()
+        state.offline
+            .groupBy { shows["${it.shareId}/${it.linkId}"] }
+            .map { (title, files) ->
+                OfflineGroup(title?.displayName ?: "Not in the library", title, files)
+            }
+            .sortedBy { it.name }
+    }
+    // Deleting a saved episode asks first: it is the viewer's own choice to
+    // keep it, and getting it back is a download, not a tap.
+    var deleting by remember { mutableStateOf<OfflineRecord?>(null) }
+    TabPage("Downloads", padding) { body ->
+        if (retained.isEmpty() && state.offline.isEmpty()) {
+            Box(Modifier.fillMaxSize().padding(body)) {
+                EmptyState("No downloads", "Episodes, seasons and shows saved offline appear here.")
+            }
+            return@TabPage
+        }
+        LazyColumn(
+            modifier = Modifier.fillMaxSize().padding(body),
+            contentPadding = PaddingValues(bottom = 24.dp),
+        ) {
+            if (state.offline.isNotEmpty()) {
+                item(key = "summary") {
+                    Text(
+                        "${state.offline.size} ${if (state.offline.size == 1) "episode" else "episodes"} · " +
+                            "${formatBytes(state.offline.sumOf { it.size })} on this device",
+                        style = MaterialTheme.typography.bodyMedium,
+                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                        modifier = Modifier.padding(horizontal = 16.dp, vertical = 4.dp),
+                    )
+                }
+            }
+            // What is still arriving comes first: it is the part of the page
+            // that changes, and the part with something to do.
+            if (retained.isNotEmpty()) {
+                item(key = "in-progress") { SectionHeading("In progress") }
+                items(retained, key = { "partial/${it.shareId}/${it.linkId}" }) { download ->
+                    PartialRow(download, onPause, onResume, onDeletePartial)
+                }
+            }
+            // Under the show they belong to, as on desktop: a saved season is
+            // fourteen rows, and fourteen rows of "Episode 3" name nothing.
+            groups.forEach { group ->
+                item(key = "group/${group.name}") {
+                    SectionHeading(
+                        group.name,
+                        "${group.files.size} ${if (group.files.size == 1) "episode" else "episodes"} · " +
+                            formatBytes(group.files.sumOf { it.size }),
+                    )
+                }
+                items(group.files, key = { "${it.shareId}/${it.linkId}" }) { file ->
+                    SavedRow(file, group.title, onDelete = { deleting = file }, onPlay = onPlay, onOpen = onOpen)
+                }
+            }
+        }
+    }
+    deleting?.let { file ->
+        AlertDialog(
+            onDismissRequest = { deleting = null },
+            title = { Text("Delete this download?") },
+            text = {
+                Text(
+                    "${file.episode?.label ?: "The episode"} (${formatBytes(file.size)}) leaves this device. " +
+                        "It still streams, and can be downloaded again.",
+                )
+            },
+            confirmButton = {
+                DangerButton(onClick = {
+                    deleting = null
+                    onRemove(file)
+                }) { Text("Delete") }
+            },
+            dismissButton = { TonalButton(onClick = { deleting = null }) { Text("Cancel") } },
+        )
+    }
+}
+
+@Composable
+private fun SectionHeading(title: String, caption: String? = null) {
+    Column(Modifier.padding(start = 16.dp, end = 16.dp, top = 20.dp, bottom = 4.dp)) {
+        Text(title, style = MaterialTheme.typography.titleMedium, maxLines = 1, overflow = TextOverflow.Ellipsis)
+        caption?.let {
+            Text(it, style = MaterialTheme.typography.bodySmall, color = MaterialTheme.colorScheme.onSurfaceVariant)
+        }
+    }
+}
+
+/** A saved episode: its still, what it is, its size, and a way to remove it. */
+@Composable
+private fun SavedRow(
+    file: OfflineRecord,
+    title: TitleRecord?,
+    onDelete: () -> Unit,
+    onPlay: (TitleRecord, Int) -> Unit,
+    onOpen: (TitleRecord) -> Unit,
+) {
+    val episode = file.episode
+    // What a download is for: tapping it plays it, from where it was left,
+    // without going back through the library to find it.
+    val index = title?.seasons?.flatMap(SeasonRecord::episodes)?.indexOfFirst { it.linkId == file.linkId } ?: -1
+    ListItem(
+        modifier = if (title != null && index >= 0) {
+            Modifier.clickable(onClickLabel = "Play") { onPlay(title, index) }
+        } else {
+            Modifier
+        },
+        leadingContent = {
+            RemoteArtwork(
+                episode?.stillUrl ?: title?.backdropUrl,
+                title?.name ?: file.linkId,
+                Modifier.width(96.dp).aspectRatio(16f / 9f).clip(MaterialTheme.shapes.small),
+                fallback = episode?.thumbnailSource,
+                labelled = episode == null,
+            )
+        },
+        headlineContent = {
+            Text(episode?.heading(0) ?: file.linkId, maxLines = 2, overflow = TextOverflow.Ellipsis)
+        },
+        supportingContent = {
+            Text(listOfNotNull(episode?.label, formatBytes(file.size)).joinToString(" · "))
+        },
+        trailingContent = {
+            Row {
+                title?.let {
+                    IconButton(onClick = { onOpen(it) }) {
+                        Icon(Icons.Outlined.Info, contentDescription = "Open ${it.displayName}")
+                    }
+                }
+                IconButton(onClick = onDelete) {
+                    Icon(Icons.Outlined.Delete, contentDescription = "Delete download")
+                }
+            }
+        },
+        colors = ListItemDefaults.colors(containerColor = Color.Transparent),
+    )
+}
+
+/**
+ * A download not yet finished: how far it has got, why it stopped if it did,
+ * and pause or resume beside cancel.
+ */
+@Composable
+private fun PartialRow(
+    download: RetainedDownload,
+    onPause: (RetainedDownload) -> Unit,
+    onResume: (RetainedDownload) -> Unit,
+    onDeletePartial: (RetainedDownload) -> Unit,
+) {
+    val active = download.status == RetainedDownload.STATUS_RUNNING ||
+        download.status == RetainedDownload.STATUS_QUEUED
+    ListItem(
+        headlineContent = { Text(download.label, maxLines = 2, overflow = TextOverflow.Ellipsis) },
+        supportingContent = {
+            Column {
+                Text(downloadStatusLine(download, rememberQueueReason(download)))
+                if (download.total > 0L) {
+                    AccentProgress(
+                        progress = { (download.downloaded.toFloat() / download.total).coerceIn(0f, 1f) },
+                        modifier = Modifier.fillMaxWidth().padding(top = 8.dp),
+                    )
+                }
+                download.error?.let { Text(it, color = MaterialTheme.colorScheme.error) }
+            }
+        },
+        trailingContent = {
+            Row(verticalAlignment = Alignment.CenterVertically) {
+                if (active) {
+                    IconButton(onClick = { onPause(download) }) {
+                        Icon(Icons.Default.Pause, contentDescription = "Pause download")
+                    }
+                } else {
+                    IconButton(onClick = { onResume(download) }) {
+                        Icon(Icons.Default.PlayArrow, contentDescription = "Resume download")
+                    }
+                }
+                // What has arrived so far is discarded; nothing finished is.
+                IconButton(onClick = { onDeletePartial(download) }) {
+                    Icon(Icons.Default.Close, contentDescription = "Cancel and delete what has arrived")
+                }
+            }
+        },
+        colors = ListItemDefaults.colors(containerColor = Color.Transparent),
+    )
+}

android/app/src/main/java/io/narl/protonstream/ui/HistoryScreen.kt

@@ -0,0 +1,183 @@
+package io.narl.protonstream.ui
+
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.aspectRatio
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Close
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.ui.unit.dp
+import io.narl.protonstream.ui.theme.AccentProgress
+import java.time.Instant
+import java.time.LocalDate
+import java.time.ZoneId
+import java.time.format.DateTimeFormatter
+import java.time.format.TextStyle
+import java.util.Locale
+import uniffi.pstr_android.EpisodeRecord
+import uniffi.pstr_android.SeasonRecord
+import uniffi.pstr_android.TitleRecord
+
+/** One played episode, with the title it belongs to and its place in that title's playlist. */
+internal data class Played(val title: TitleRecord, val episode: EpisodeRecord, val index: Int)
+
+/**
+ * Every episode that has been started or finished, newest first — the
+ * desktop's `Library::history`, over the records the library already holds.
+ *
+ * A row marked unwatched again sits at position zero, which is "never played"
+ * for every purpose here, so it is left out. Progress stands in for the
+ * position: it is non-zero exactly when the position is.
+ */
+internal fun history(titles: List<TitleRecord>): List<Played> =
+    titles.flatMap { title ->
+        title.seasons.flatMap(SeasonRecord::episodes).withIndex()
+            .filter { (_, episode) -> episode.watched || (episode.progress ?: 0.0) > 0.0 }
+            .map { (index, episode) -> Played(title, episode, index) }
+    }.sortedByDescending { it.episode.lastPlayed }
+
+/**
+ * "Today", "Yesterday", a weekday within the last week, then a date — how the
+ * history page heads each day.
+ */
+internal fun dayHeading(day: LocalDate, today: LocalDate, locale: Locale = Locale.getDefault()): String = when {
+    day == today -> "Today"
+    day == today.minusDays(1) -> "Yesterday"
+    day.isAfter(today.minusDays(7)) -> day.dayOfWeek.getDisplayName(TextStyle.FULL, locale)
+    day.year == today.year -> day.format(DateTimeFormatter.ofPattern("d MMMM", locale))
+    else -> day.format(DateTimeFormatter.ofPattern("d MMMM yyyy", locale))
+}
+
+@Composable
+internal fun HistoryScreen(
+    state: AppUiState,
+    onPlay: (TitleRecord, Int) -> Unit,
+    onTitle: (TitleRecord) -> Unit,
+    onRemove: (TitleRecord, EpisodeRecord) -> Unit,
+    padding: PaddingValues,
+    zone: ZoneId = remember { ZoneId.systemDefault() },
+    today: LocalDate = LocalDate.now(zone),
+) {
+    val days = remember(state.titles) {
+        history(state.titles).groupBy { Instant.ofEpochSecond(it.episode.lastPlayed).atZone(zone).toLocalDate() }
+    }
+    if (days.isEmpty()) {
+        TabPage("History", padding) { body ->
+            Box(Modifier.fillMaxSize().padding(body)) {
+                EmptyState("Nothing watched yet", "Episodes you play show up here, newest first.")
+            }
+        }
+        return
+    }
+    TabPage("History", padding) { body ->
+        LazyColumn(Modifier.fillMaxSize().padding(body), contentPadding = PaddingValues(bottom = 24.dp)) {
+            days.forEach { (day, played) ->
+                item(key = "day/$day") {
+                    Text(
+                        dayHeading(day, today),
+                        style = MaterialTheme.typography.titleSmall,
+                        color = MaterialTheme.colorScheme.primary,
+                        modifier = Modifier.padding(start = 16.dp, end = 16.dp, top = 20.dp, bottom = 4.dp),
+                    )
+                }
+                items(played, key = { "${it.episode.shareId}/${it.episode.linkId}" }) { entry ->
+                    HistoryRow(
+                        entry,
+                        onPlay = { onPlay(entry.title, entry.index) },
+                        onTitle = { onTitle(entry.title) },
+                        onRemove = { onRemove(entry.title, entry.episode) },
+                    )
+                }
+            }
+        }
+    }
+}
+
+/**
+ * The still plays the episode, the text opens its title, and the cross takes
+ * it off the page — the same three targets the desktop row has.
+ */
+@Composable
+private fun HistoryRow(entry: Played, onPlay: () -> Unit, onTitle: () -> Unit, onRemove: () -> Unit) {
+    val episode = entry.episode
+    Row(
+        Modifier.fillMaxWidth().padding(start = 16.dp, end = 4.dp, top = 6.dp, bottom = 6.dp),
+        verticalAlignment = Alignment.CenterVertically,
+    ) {
+        Box(
+            Modifier
+                .width(128.dp)
+                .aspectRatio(16f / 9f)
+                .clip(MaterialTheme.shapes.small)
+                .clickable(onClick = onPlay),
+        ) {
+            RemoteArtwork(
+                episode.stillUrl ?: entry.title.backdropUrl,
+                episode.label,
+                Modifier.fillMaxSize(),
+                fallback = episode.thumbnailSource,
+                labelled = false,
+            )
+            episode.progress?.takeIf { !episode.watched }?.let { progress ->
+                AccentProgress(
+                    progress = { progress.toFloat().coerceIn(0f, 1f) },
+                    modifier = Modifier.fillMaxWidth().align(Alignment.BottomCenter),
+                )
+            }
+        }
+        Column(Modifier.weight(1f).clickable(onClick = onTitle).padding(horizontal = 12.dp, vertical = 4.dp)) {
+            Text(
+                entry.title.displayName,
+                style = MaterialTheme.typography.titleSmall,
+                maxLines = 1,
+                overflow = TextOverflow.Ellipsis,
+            )
+            Text(
+                episode.providerName?.let { "${episode.label} · $it" } ?: episode.label,
+                style = MaterialTheme.typography.bodySmall,
+                maxLines = 1,
+                overflow = TextOverflow.Ellipsis,
+            )
+            Text(
+                if (episode.watched) "Finished" else episode.stoppedAt(),
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+        }
+        IconButton(onClick = onRemove) {
+            Icon(Icons.Default.Close, contentDescription = "Remove from history")
+        }
+    }
+}
+
+/** "Stopped at 12:04 of 23:40", or as much of it as is known. */
+private fun EpisodeRecord.stoppedAt(): String {
+    val at = resumeAt ?: return "Started"
+    val duration = progress?.takeIf { it > 0.0 }?.let { at / it }
+    return "Stopped at ${clock(at)}" + (duration?.let { " of ${clock(it)}" } ?: "")
+}
+
+private fun clock(seconds: Double): String {
+    val total = seconds.toInt().coerceAtLeast(0)
+    val hours = total / 3_600
+    return if (hours > 0) "%d:%02d:%02d".format(hours, total % 3_600 / 60, total % 60)
+    else "%d:%02d".format(total / 60, total % 60)
+}

android/app/src/main/java/io/narl/protonstream/ui/LanguagePicker.kt

@@ -0,0 +1,183 @@
+package io.narl.protonstream.ui
+
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.heightIn
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.HorizontalDivider
+import androidx.compose.material3.ListItem
+import androidx.compose.material3.ListItemDefaults
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.RadioButton
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.semantics.Role
+import androidx.compose.ui.unit.dp
+import io.narl.protonstream.ui.theme.AccentButton
+import io.narl.protonstream.ui.theme.TonalButton
+
+/**
+ * The languages offered by name, as the three-letter tag a Matroska file
+ * carries.
+ *
+ * The same short list the desktop names tracks from (`pstr-player`'s
+ * `language_name`): what the shares this app is pointed at actually contain.
+ * mpv treats the two- and three-letter forms of a language as one, so the tag
+ * chosen here also matches a file that says "ja". Anything else is still one
+ * typed tag away.
+ */
+internal val LANGUAGES: List<Pair<String, String>> = listOf(
+    "jpn" to "Japanese",
+    "eng" to "English",
+    "ger" to "German",
+    "fre" to "French",
+    "spa" to "Spanish",
+    "ita" to "Italian",
+    "por" to "Portuguese",
+    "dut" to "Dutch",
+    "rus" to "Russian",
+    "pol" to "Polish",
+    "swe" to "Swedish",
+    "dan" to "Danish",
+    "nor" to "Norwegian",
+    "fin" to "Finnish",
+    "cze" to "Czech",
+    "hun" to "Hungarian",
+    "tur" to "Turkish",
+    "ara" to "Arabic",
+    "heb" to "Hebrew",
+    "hin" to "Hindi",
+    "kor" to "Korean",
+    "chi" to "Chinese",
+    "tha" to "Thai",
+    "vie" to "Vietnamese",
+    "ukr" to "Ukrainian",
+    "rum" to "Romanian",
+    "gre" to "Greek",
+    "ind" to "Indonesian",
+    "may" to "Malay",
+)
+
+/**
+ * "Japanese", for a tag in any of the forms a file or the desktop may have
+ * stored — "jpn", "ja", "JA-jp" — and the tag itself for one not on the list.
+ * Null is no preference.
+ */
+internal fun languageLabel(tag: String?): String {
+    val value = tag?.trim()?.takeIf(String::isNotEmpty) ?: return "No preference"
+    return languageOf(value)?.second ?: value
+}
+
+/** The listed language a tag names, matching either ISO 639 form. */
+private fun languageOf(tag: String): Pair<String, String>? {
+    val base = tag.split('-', '_').first().lowercase()
+    return LANGUAGES.firstOrNull { (code, _) -> code == base || TWO_LETTER[code] == base || terminology(code) == base }
+}
+
+/** ISO 639-2/T, for the handful whose bibliographic code differs. */
+private fun terminology(code: String): String? = when (code) {
+    "ger" -> "deu"
+    "fre" -> "fra"
+    "dut" -> "nld"
+    "cze" -> "ces"
+    "chi" -> "zho"
+    "rum" -> "ron"
+    "gre" -> "ell"
+    "may" -> "msa"
+    else -> null
+}
+
+/** ISO 639-1, the form a file or the desktop may also have stored. */
+private val TWO_LETTER = mapOf(
+    "jpn" to "ja", "eng" to "en", "ger" to "de", "fre" to "fr", "spa" to "es", "ita" to "it",
+    "por" to "pt", "dut" to "nl", "rus" to "ru", "pol" to "pl", "swe" to "sv", "dan" to "da",
+    "nor" to "no", "fin" to "fi", "cze" to "cs", "hun" to "hu", "tur" to "tr", "ara" to "ar",
+    "heb" to "he", "hin" to "hi", "kor" to "ko", "chi" to "zh", "tha" to "th", "vie" to "vi",
+    "ukr" to "uk", "rum" to "ro", "gre" to "el", "ind" to "id", "may" to "ms",
+)
+
+/**
+ * A language preference as a row, opening a list to choose from.
+ *
+ * It was a free-text field asking for "jpn or eng", which is a question only
+ * someone who has read a Matroska header can answer.
+ */
+@Composable
+internal fun LanguageSetting(headline: String, value: String?, onChange: (String?) -> Unit) {
+    var choosing by remember { mutableStateOf(false) }
+    ListItem(
+        headlineContent = { Text(headline) },
+        supportingContent = { Text(languageLabel(value)) },
+        colors = ListItemDefaults.colors(containerColor = Color.Transparent),
+        modifier = Modifier.clickable(role = Role.Button) { choosing = true },
+    )
+    if (choosing) {
+        LanguageDialog(
+            headline,
+            value,
+            onDismiss = { choosing = false },
+            onChoose = {
+                choosing = false
+                onChange(it)
+            },
+        )
+    }
+}
+
+@Composable
+private fun LanguageDialog(headline: String, value: String?, onDismiss: () -> Unit, onChoose: (String?) -> Unit) {
+    val current = value?.let(::languageOf)?.first ?: value
+    // A tag that is not on the list starts in the field, so it is shown and
+    // can be edited rather than silently replaced.
+    var typed by remember { mutableStateOf(current?.takeIf { tag -> LANGUAGES.none { it.first == tag } }.orEmpty()) }
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        title = { Text(headline) },
+        text = {
+            Column {
+                LazyColumn(Modifier.fillMaxWidth().heightIn(max = 360.dp)) {
+                    item(key = "none") { LanguageOption("No preference", current == null) { onChoose(null) } }
+                    items(LANGUAGES, key = { it.first }) { (code, name) ->
+                        LanguageOption(name, current == code) { onChoose(code) }
+                    }
+                }
+                HorizontalDivider(Modifier.padding(vertical = 8.dp))
+                OutlinedTextField(
+                    value = typed,
+                    onValueChange = { typed = it },
+                    label = { Text("Another tag") },
+                    supportingText = { Text("As it appears in the file, such as \"tgl\"") },
+                    singleLine = true,
+                    modifier = Modifier.fillMaxWidth(),
+                )
+            }
+        },
+        confirmButton = {
+            AccentButton(enabled = typed.isNotBlank(), onClick = { onChoose(typed.trim().lowercase()) }) {
+                Text("Use tag")
+            }
+        },
+        dismissButton = { TonalButton(onClick = onDismiss) { Text("Cancel") } },
+    )
+}
+
+@Composable
+private fun LanguageOption(name: String, selected: Boolean, onClick: () -> Unit) {
+    ListItem(
+        headlineContent = { Text(name, style = MaterialTheme.typography.bodyLarge) },
+        leadingContent = { RadioButton(selected = selected, onClick = null) },
+        colors = ListItemDefaults.colors(containerColor = Color.Transparent),
+        modifier = Modifier.clickable(role = Role.RadioButton, onClick = onClick),
+    )
+}

android/app/src/main/java/io/narl/protonstream/ui/LibraryScreen.kt

@@ -0,0 +1,815 @@
+package io.narl.protonstream.ui
+
+import androidx.compose.foundation.background
+import androidx.activity.compose.BackHandler
+import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.material.icons.automirrored.filled.ArrowBack
+import androidx.compose.material.icons.filled.Refresh
+import androidx.compose.material3.LargeTopAppBar
+import androidx.compose.material3.TopAppBar
+import androidx.compose.material3.TopAppBarDefaults
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.saveable.rememberSaveable
+import androidx.compose.ui.focus.FocusRequester
+import androidx.compose.ui.focus.focusRequester
+import androidx.compose.ui.input.nestedscroll.nestedScroll
+import androidx.compose.ui.text.input.ImeAction
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Row
+import androidx.compose.ui.graphics.Brush
+import io.narl.protonstream.ui.theme.AccentButton
+import io.narl.protonstream.ui.theme.TonalButton
+import androidx.compose.material3.Surface
+import androidx.compose.ui.platform.LocalContext
+import io.narl.protonstream.settings.SettingsStore
+import io.narl.protonstream.ui.theme.QuietButton
+import java.time.LocalDate
+import androidx.compose.foundation.combinedClickable
+import androidx.compose.material.icons.filled.CheckCircle
+import androidx.compose.material.icons.filled.Download
+import androidx.compose.material.icons.filled.Edit
+import androidx.compose.material.icons.filled.Info
+import androidx.compose.material.icons.filled.PlayArrow
+import androidx.compose.material.icons.filled.RemoveCircleOutline
+import androidx.compose.material.icons.outlined.CheckCircle
+import androidx.compose.material3.ListItem
+import androidx.compose.material3.ListItemDefaults
+import androidx.compose.material3.ModalBottomSheet
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.aspectRatio
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.lazy.LazyRow
+import androidx.compose.foundation.lazy.grid.GridCells
+import androidx.compose.foundation.lazy.grid.GridItemSpan
+import androidx.compose.foundation.lazy.grid.LazyVerticalGrid
+import androidx.compose.foundation.lazy.grid.items
+import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.shape.CircleShape
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Close
+import androidx.compose.material.icons.filled.Search
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.FilterChip
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextField
+import androidx.compose.material3.TextFieldDefaults
+import androidx.compose.material3.pulltorefresh.PullToRefreshBox
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.semantics.contentDescription
+import androidx.compose.ui.semantics.semantics
+import androidx.compose.ui.semantics.clearAndSetSemantics
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.ui.unit.dp
+import io.narl.protonstream.ui.theme.AccentProgress
+import androidx.compose.material.icons.automirrored.filled.Sort
+import androidx.compose.material.icons.filled.Check
+import androidx.compose.material3.DropdownMenu
+import androidx.compose.material3.DropdownMenuItem
+import androidx.compose.material3.HorizontalDivider
+import uniffi.pstr_android.EpisodeRecord
+import uniffi.pstr_android.LibraryFilter
+import uniffi.pstr_android.LibrarySort
+import uniffi.pstr_android.SeasonRecord
+import uniffi.pstr_android.TitleRecord
+import uniffi.pstr_android.TitleType
+
+/**
+ * How many shows the continue-watching shelf holds.
+ *
+ * A shelf is a shortcut, not a second library: past about this many it is
+ * quicker to search for the thing than to scroll the shelf looking for it.
+ */
+private const val CONTINUE_WATCHING_MAX = 12
+
+/** One row of the continue-watching shelf: which episode, and where it sits. */
+private data class Resumable(
+    val title: TitleRecord,
+    val episode: EpisodeRecord,
+    val index: Int,
+    /** When the title was last played, which orders the shelf. */
+    val lastPlayed: Long,
+)
+
+/** One tile of the grid: the title drawn, and how many more of its franchise it stands for. */
+private data class Tile(val title: TitleRecord, val folded: Int)
+
+/** The desktop's names for the filters, from `browse::Filter::label`. */
+internal fun LibraryFilter.label(): String = when (this) {
+    LibraryFilter.ALL -> "All"
+    LibraryFilter.SERIES -> "Series"
+    LibraryFilter.FILMS -> "Films"
+    LibraryFilter.WATCHING -> "Watching"
+    LibraryFilter.UNWATCHED -> "Not started"
+    LibraryFilter.DOWNLOADED -> "Downloaded"
+}
+
+/** The offer of posters and synopses, and its two answers. */
+internal class MetadataOffer(val onOpenSettings: () -> Unit, val onDismiss: () -> Unit)
+
+@Composable
+private fun MetadataOfferCard(offer: MetadataOffer) {
+    Surface(color = MaterialTheme.colorScheme.surfaceContainer, shape = MaterialTheme.shapes.medium) {
+        Column(Modifier.fillMaxWidth().padding(start = 16.dp, end = 8.dp, top = 12.dp, bottom = 4.dp)) {
+            Text("Add posters and synopses?", style = MaterialTheme.typography.titleSmall)
+            Text(
+                "Turning it on in Settings sends the titles in your library — not your files, and " +
+                    "nothing about what you have watched — to AniList or TMDB.",
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+                modifier = Modifier.padding(top = 4.dp, end = 8.dp),
+            )
+            Row(Modifier.align(Alignment.End)) {
+                QuietButton(onClick = offer.onDismiss) { Text("Not now") }
+                QuietButton(onClick = offer.onOpenSettings) { Text("Open settings") }
+            }
+        }
+    }
+}
+
+/** A row above the grid: titles that share a director, a studio or a genre. */
+private data class Shelf(val label: String, val titles: List<TitleRecord>)
+
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+internal fun LibraryScreen(
+    state: AppUiState,
+    onSearch: (String) -> Unit,
+    onResume: (TitleRecord, Int) -> Unit,
+    onTitle: (TitleRecord) -> Unit,
+    onRefresh: () -> Unit,
+    onSetTitleWatched: (TitleRecord, Boolean) -> Unit,
+    onForgetPosition: (TitleRecord, EpisodeRecord) -> Unit,
+    padding: PaddingValues,
+    onMatchChanged: () -> Unit = {},
+    onError: (Throwable) -> Unit = {},
+    onArrange: (LibrarySort, Boolean) -> Unit = { _, _ -> },
+    onAddShare: () -> Unit = {},
+    onOpenSettings: () -> Unit = {},
+    onFilter: (LibraryFilter) -> Unit = {},
+) {
+    val download = rememberDownload()
+    val context = LocalContext.current
+    // Posters and synopses, offered once there is a library to put them on
+    // and never turned on unasked: switching them on sends title names out.
+    var offerDismissed by remember { mutableStateOf(SettingsStore(context).metadataOfferDismissed) }
+    // What a long press opened a menu for: a title, or a Continue watching card.
+    var menuFor by remember { mutableStateOf<TitleRecord?>(null) }
+    var menuResume by remember { mutableStateOf<Resumable?>(null) }
+    var matching by remember { mutableStateOf<TitleRecord?>(null) }
+    // Most recently played first, one episode per show: a shelf that lists four
+    // episodes of the same series is a shelf with room for nothing else.
+    // What to go on with is the engine's call (`continueIndex`): the
+    // part-watched episode, or the one after the episode finished last.
+    val resumable = remember(state.titles) {
+        state.titles.mapNotNull { title ->
+            val index = title.continueIndex?.toInt() ?: return@mapNotNull null
+            val playlist = title.seasons.flatMap(SeasonRecord::episodes)
+            playlist.getOrNull(index)?.let { episode ->
+                Resumable(title, episode, index, playlist.maxOf { it.lastPlayed })
+            }
+        }.sortedByDescending { it.lastPlayed }.take(CONTINUE_WATCHING_MAX)
+    }
+    // Search is an icon until it is wanted: a permanent field above the
+    // library spent a band of every visit on something used in few of them.
+    var searching by rememberSaveable { mutableStateOf(state.query.isNotEmpty()) }
+    val closeSearch = {
+        searching = false
+        onSearch("")
+    }
+    BackHandler(enabled = searching, onBack = closeSearch)
+    // The large title folds into the bar as the grid scrolls, and comes back
+    // only at the top: the page says what it is on arrival, then gets out of
+    // the way.
+    val scroll = TopAppBarDefaults.exitUntilCollapsedScrollBehavior()
+    Column(Modifier.fillMaxSize().nestedScroll(scroll.nestedScrollConnection)) {
+        if (searching) {
+            SearchBar(state.query, onSearch, closeSearch)
+        } else {
+            LargeTopAppBar(
+                title = { Text("Library") },
+                actions = {
+                    IconButton(onClick = { searching = true }) {
+                        Icon(Icons.Default.Search, contentDescription = "Search library")
+                    }
+                    ArrangeMenu(state.sort, state.grouped, onArrange)
+                    // Pull to refresh is the gesture; the icon stays for a
+                    // viewer who does not know it.
+                    IconButton(onClick = onRefresh, enabled = !state.refreshing) {
+                        Icon(Icons.Default.Refresh, contentDescription = "Refresh")
+                    }
+                },
+                colors = pageBarColors(),
+                scrollBehavior = scroll,
+            )
+        }
+        PullToRefreshBox(
+            isRefreshing = state.refreshing,
+            onRefresh = onRefresh,
+            modifier = Modifier.weight(1f).padding(padding),
+        ) {
+            when {
+                state.loading -> LibrarySkeleton()
+                state.titles.isEmpty() && state.query.isNotBlank() -> EmptyState(
+                    "Nothing matches",
+                    "No title in the library is called “${state.query.trim()}”.",
+                )
+                // A share just added: say it is being looked through, rather
+                // than offer to add the one that is already filling the page.
+                state.titles.isEmpty() && state.activity != null -> EmptyState(
+                    "Looking through the share",
+                    "${state.activity} Its titles appear here once it has been listed.",
+                )
+                state.titles.isEmpty() -> EmptyState(
+                    "Your library is empty",
+                    "Add a Proton Drive share link, and everything playable behind it shows up here.",
+                    action = "Add a share" to onAddShare,
+                )
+                else -> LibraryGrid(
+                    state,
+                    resumable,
+                    onResume,
+                    onTitle,
+                    onTitleMenu = { menuFor = it },
+                    onResumeMenu = { menuResume = it },
+                    onFilter = onFilter,
+                    metadataOffer = if (state.metadataSettings.enabled || offerDismissed) {
+                        null
+                    } else {
+                        MetadataOffer(onOpenSettings) {
+                            offerDismissed = true
+                            SettingsStore(context).metadataOfferDismissed = true
+                        }
+                    },
+                )
+            }
+        }
+    }
+    menuFor?.let { title ->
+        val playlist = title.seasons.flatMap(SeasonRecord::episodes)
+        val allWatched = title.episodeCount > 0uL && title.watchedCount == title.episodeCount
+        TileMenu(title.displayName, title.caption(), onDismiss = { menuFor = null }) {
+            MenuRow(Icons.Default.PlayArrow, if (playlist.any { it.resumeAt != null }) "Resume" else "Play") {
+                onResume(title, nextUpIndex(playlist, title.continueIndex))
+            }
+            MenuRow(Icons.Default.Info, "Open") { onTitle(title) }
+            MenuRow(Icons.Default.Download, "Download all") { download(playlist, title.displayName) }
+            MenuRow(
+                if (allWatched) Icons.Outlined.CheckCircle else Icons.Default.CheckCircle,
+                if (allWatched) "Mark unwatched" else "Mark watched",
+            ) { onSetTitleWatched(title, !allWatched) }
+            // The same search the title page offers, for the tile that is
+            // plainly wrong — the wrong poster is what the grid shows.
+            MenuRow(Icons.Default.Edit, "Change match") { matching = title }
+        }
+    }
+    matching?.let { title ->
+        ChangeMatchDialog(
+            title = title,
+            onDismiss = { matching = null },
+            onChanged = {
+                matching = null
+                onMatchChanged()
+            },
+            onError = onError,
+        )
+    }
+    menuResume?.let { entry ->
+        TileMenu(
+            entry.title.displayName,
+            entry.episode.label,
+            onDismiss = { menuResume = null },
+        ) {
+            MenuRow(Icons.Default.PlayArrow, "Resume") { onResume(entry.title, entry.index) }
+            MenuRow(Icons.Default.Info, "Open") { onTitle(entry.title) }
+            MenuRow(Icons.Default.RemoveCircleOutline, "Remove from Continue watching") {
+                onForgetPosition(entry.title, entry.episode)
+            }
+        }
+    }
+}
+
+/**
+ * The grid's order, and whether a franchise is one tile or one per title —
+ * the same choices the desktop offers beside its grid, behind one icon here
+ * because a phone's bar has room for three.
+ */
+@Composable
+private fun ArrangeMenu(sort: LibrarySort, grouped: Boolean, onArrange: (LibrarySort, Boolean) -> Unit) {
+    var open by remember { mutableStateOf(false) }
+    Box {
+        IconButton(onClick = { open = true }) {
+            Icon(Icons.AutoMirrored.Filled.Sort, contentDescription = "Sort library")
+        }
+        DropdownMenu(expanded = open, onDismissRequest = { open = false }) {
+            LibrarySort.entries.forEach { option ->
+                DropdownMenuItem(
+                    text = { Text(option.label()) },
+                    leadingIcon = {
+                        if (option == sort) Icon(Icons.Default.Check, contentDescription = null)
+                    },
+                    onClick = {
+                        open = false
+                        onArrange(option, grouped)
+                    },
+                )
+            }
+            HorizontalDivider()
+            DropdownMenuItem(
+                text = { Text("One tile per franchise") },
+                leadingIcon = {
+                    if (grouped) Icon(Icons.Default.Check, contentDescription = null)
+                },
+                onClick = {
+                    open = false
+                    onArrange(sort, !grouped)
+                },
+            )
+        }
+    }
+}
+
+/** What each order is called. The desktop says the same. */
+private fun LibrarySort.label() = when (this) {
+    LibrarySort.NAME -> "A – Z"
+    LibrarySort.RECENT -> "Recently watched"
+    LibrarySort.ADDED -> "Recently added"
+    LibrarySort.RELEASE -> "Newest"
+    LibrarySort.RATING -> "Highest rated"
+    LibrarySort.POPULARITY -> "Most popular"
+}
+
+/**
+ * The bar while searching: back closes the search and clears it, and the field
+ * takes the keyboard as soon as it opens, since opening it is asking to type.
+ */
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+private fun SearchBar(query: String, onSearch: (String) -> Unit, onClose: () -> Unit) {
+    val focus = remember { FocusRequester() }
+    LaunchedEffect(Unit) { focus.requestFocus() }
+    TopAppBar(
+        navigationIcon = {
+            IconButton(onClick = onClose) {
+                Icon(Icons.AutoMirrored.Filled.ArrowBack, contentDescription = "Close search")
+            }
+        },
+        title = {
+            // A filled pill rather than an outlined form field: search is how
+            // the page is navigated, not a value being entered.
+            TextField(
+                value = query,
+                onValueChange = onSearch,
+                modifier = Modifier.fillMaxWidth().padding(end = 8.dp).focusRequester(focus),
+                singleLine = true,
+                shape = CircleShape,
+                placeholder = { Text("Search library") },
+                trailingIcon = {
+                    if (query.isNotEmpty()) {
+                        IconButton(onClick = { onSearch("") }) {
+                            Icon(Icons.Default.Close, contentDescription = "Clear search")
+                        }
+                    }
+                },
+                keyboardOptions = KeyboardOptions(imeAction = ImeAction.Search),
+                colors = TextFieldDefaults.colors(
+                    focusedIndicatorColor = Color.Transparent,
+                    unfocusedIndicatorColor = Color.Transparent,
+                    disabledIndicatorColor = Color.Transparent,
+                ),
+            )
+        },
+        colors = pageBarColors(),
+    )
+}
+
+/**
+ * A long press's menu, from the bottom of the screen where the thumb already
+ * is. Each row closes it before doing its thing.
+ */
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+private fun TileMenu(
+    heading: String,
+    caption: String,
+    onDismiss: () -> Unit,
+    rows: @Composable MenuScope.() -> Unit,
+) {
+    ModalBottomSheet(onDismissRequest = onDismiss) {
+        Column(Modifier.padding(bottom = 24.dp)) {
+            Text(
+                heading,
+                style = MaterialTheme.typography.titleMedium,
+                maxLines = 1,
+                overflow = TextOverflow.Ellipsis,
+                modifier = Modifier.padding(horizontal = 24.dp),
+            )
+            Text(
+                caption,
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+                modifier = Modifier.padding(start = 24.dp, end = 24.dp, bottom = 8.dp),
+            )
+            MenuScope(onDismiss).rows()
+        }
+    }
+}
+
+private class MenuScope(val dismiss: () -> Unit)
+
+@Composable
+private fun MenuScope.MenuRow(icon: ImageVector, label: String, onClick: () -> Unit) {
+    ListItem(
+        headlineContent = { Text(label) },
+        leadingContent = { Icon(icon, contentDescription = null) },
+        colors = ListItemDefaults.colors(containerColor = Color.Transparent),
+        modifier = Modifier.clickable { dismiss(); onClick() }.padding(horizontal = 8.dp),
+    )
+}
+
+@Composable
+private fun LibraryGrid(
+    state: AppUiState,
+    resumable: List<Resumable>,
+    onResume: (TitleRecord, Int) -> Unit,
+    onTitle: (TitleRecord) -> Unit,
+    onTitleMenu: (TitleRecord) -> Unit,
+    onResumeMenu: (Resumable) -> Unit,
+    onFilter: (LibraryFilter) -> Unit = {},
+    metadataOffer: MetadataOffer? = null,
+) {
+    // The arrangement names titles by key; before it has arrived, the titles
+    // as they came are the grid.
+    val byKey = remember(state.titles) { state.titles.associateBy { it.key } }
+    val tiles = remember(state.titles, state.arrangement) {
+        state.arrangement?.tiles?.mapNotNull { tile -> byKey[tile.key]?.let { Tile(it, tile.folded.toInt()) } }
+            ?: state.titles.map { Tile(it, 0) }
+    }
+    val shelves = remember(state.titles, state.arrangement) {
+        state.arrangement?.shelves.orEmpty()
+            .map { shelf -> Shelf(shelf.label, shelf.keys.mapNotNull(byKey::get)) }
+            .filter { it.titles.isNotEmpty() }
+    }
+    // Posters, three across on a phone. Cropped backdrops at full width fitted
+    // two titles to a screen, which is a library read one row at a time.
+    LazyVerticalGrid(
+        columns = GridCells.Adaptive(108.dp),
+        modifier = Modifier.fillMaxSize(),
+        horizontalArrangement = Arrangement.spacedBy(12.dp),
+        verticalArrangement = Arrangement.spacedBy(16.dp),
+        contentPadding = PaddingValues(start = 16.dp, end = 16.dp, top = 8.dp, bottom = 24.dp),
+    ) {
+        // Above the grid, and only when there is something in it: what a viewer
+        // opening the app wants is almost always the thing they were part way
+        // through. Inside the grid rather than pinned over it, so the shelf
+        // scrolls away with the rest.
+        if (metadataOffer != null && state.query.isBlank()) {
+            item(key = "metadata-offer", span = { GridItemSpan(maxLineSpan) }) { MetadataOfferCard(metadataOffer) }
+        }
+        val featured = if (state.query.isBlank()) featured(state.titles, resumable) else null
+        featured?.let { title ->
+            item(key = "featured", span = { GridItemSpan(maxLineSpan) }) {
+                FeaturedBanner(
+                    title,
+                    resume = resumable.firstOrNull { it.title.key == title.key },
+                    onPlay = { onResume(title, it) },
+                    onOpen = { onTitle(title) },
+                )
+            }
+        }
+        if (state.query.isBlank() && resumable.isNotEmpty()) {
+            item(key = "continue-watching", span = { GridItemSpan(maxLineSpan) }) {
+                Column {
+                    Text("Continue watching", style = MaterialTheme.typography.titleMedium)
+                    LazyRow(
+                        horizontalArrangement = Arrangement.spacedBy(12.dp),
+                        contentPadding = PaddingValues(top = 10.dp),
+                    ) {
+                        items(resumable, key = { "${it.episode.shareId}/${it.episode.linkId}" }) { entry ->
+                            ContinueCard(
+                                entry,
+                                onClick = { onResume(entry.title, entry.index) },
+                                onLongClick = { onResumeMenu(entry) },
+                            )
+                        }
+                    }
+                }
+            }
+        }
+        if (state.query.isBlank()) {
+            // Only over the whole library: under a filter, a shelf of titles
+            // the grid below is hiding reads as the filter not working. The
+            // bridge leaves them out too; this covers the frame before it.
+            shelves.takeIf { state.filter == LibraryFilter.ALL }.orEmpty().forEach { shelf ->
+                item(key = "shelf-${shelf.label}", span = { GridItemSpan(maxLineSpan) }) {
+                    Column {
+                        Text(shelf.label, style = MaterialTheme.typography.titleMedium)
+                        LazyRow(
+                            horizontalArrangement = Arrangement.spacedBy(12.dp),
+                            contentPadding = PaddingValues(top = 10.dp),
+                        ) {
+                            items(shelf.titles, key = { it.key }) { title ->
+                                PosterTile(
+                                    title,
+                                    onClick = { onTitle(title) },
+                                    onLongClick = { onTitleMenu(title) },
+                                    modifier = Modifier.width(SHELF_TILE_WIDTH),
+                                    shared = false,
+                                )
+                            }
+                        }
+                    }
+                }
+            }
+            item(key = "library-heading", span = { GridItemSpan(maxLineSpan) }) {
+                Column {
+                    if (resumable.isNotEmpty() || shelves.isNotEmpty()) {
+                        Text("All titles", style = MaterialTheme.typography.titleMedium, modifier = Modifier.padding(top = 8.dp))
+                    }
+                    LazyRow(horizontalArrangement = Arrangement.spacedBy(8.dp)) {
+                        items(LibraryFilter.entries, key = { it.name }) { filter ->
+                            FilterChip(
+                                selected = filter == state.filter,
+                                onClick = { onFilter(filter) },
+                                label = { Text(filter.label()) },
+                            )
+                        }
+                    }
+                }
+            }
+            if (tiles.isEmpty() && state.filter != LibraryFilter.ALL) {
+                item(key = "filtered-out", span = { GridItemSpan(maxLineSpan) }) {
+                    Text(
+                        "Nothing in the library fits that filter.",
+                        style = MaterialTheme.typography.bodyMedium,
+                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                    )
+                }
+            }
+        }
+        items(tiles, key = { it.title.key }) { tile ->
+            PosterTile(
+                tile.title,
+                onClick = { onTitle(tile.title) },
+                onLongClick = { onTitleMenu(tile.title) },
+                folded = tile.folded,
+            )
+        }
+    }
+}
+
+/**
+ * The grid's shape before the catalog has answered: posters and their two
+ * lines of text as blocks, so the page does not jump when the titles land.
+ */
+@Composable
+private fun LibrarySkeleton() {
+    LazyVerticalGrid(
+        columns = GridCells.Adaptive(108.dp),
+        modifier = Modifier.fillMaxSize(),
+        horizontalArrangement = Arrangement.spacedBy(12.dp),
+        verticalArrangement = Arrangement.spacedBy(16.dp),
+        contentPadding = PaddingValues(start = 16.dp, end = 16.dp, top = 8.dp, bottom = 24.dp),
+        userScrollEnabled = false,
+    ) {
+        items(SKELETON_TILES) {
+            Column {
+                Skeleton(Modifier.fillMaxWidth().aspectRatio(2f / 3f).clip(MaterialTheme.shapes.medium))
+                Spacer(Modifier.height(8.dp))
+                Skeleton(Modifier.fillMaxWidth(0.8f).height(12.dp).clip(MaterialTheme.shapes.small))
+                Spacer(Modifier.height(6.dp))
+                Skeleton(Modifier.fillMaxWidth(0.5f).height(10.dp).clip(MaterialTheme.shapes.small))
+            }
+        }
+    }
+}
+
+/** A shelf's covers: a little narrower than the grid's, so the row reads as a row. */
+private val SHELF_TILE_WIDTH = 112.dp
+
+/** Enough placeholder tiles to fill a tablet's first screen. */
+private const val SKELETON_TILES = 18
+
+/**
+ * The title the banner shows: the one watched last, or with nothing part
+ * watched, one of the titles the provider has a backdrop for, turning over
+ * once a day — the desktop's `featured`.
+ */
+private fun featured(titles: List<TitleRecord>, resumable: List<Resumable>): TitleRecord? {
+    resumable.firstOrNull()?.let { return it.title }
+    val pictured = titles.filter { it.backdropUrl != null }
+    if (pictured.isEmpty()) return null
+    return pictured[(LocalDate.now().toEpochDay() % pictured.size).toInt()]
+}
+
+/** Large art behind the name, rating, genres and three lines of synopsis. */
+@Composable
+private fun FeaturedBanner(title: TitleRecord, resume: Resumable?, onPlay: (Int) -> Unit, onOpen: () -> Unit) {
+    val playlist = remember(title) { title.seasons.flatMap(SeasonRecord::episodes) }
+    Box(Modifier.fillMaxWidth().aspectRatio(4f / 3f).clip(MaterialTheme.shapes.large)) {
+        RemoteArtwork(
+            title.backdropUrl ?: title.posterUrl,
+            title.displayName,
+            Modifier.fillMaxSize(),
+            fallback = title.thumbnailSource,
+            labelled = false,
+        )
+        Box(
+            Modifier.fillMaxSize().background(
+                Brush.verticalGradient(0.35f to Color.Transparent, 1f to Color.Black.copy(alpha = 0.85f)),
+            ),
+        )
+        Column(Modifier.align(Alignment.BottomStart).padding(16.dp)) {
+            Text(
+                title.displayName,
+                style = MaterialTheme.typography.headlineMedium,
+                color = Color.White,
+                maxLines = 2,
+                overflow = TextOverflow.Ellipsis,
+            )
+            Text(
+                listOfNotNull(
+                    title.rating?.let { "★ %.1f".format(it) },
+                    title.genres.takeIf { it.isNotEmpty() }?.take(3)?.joinToString(", "),
+                ).joinToString("  ·  ").ifEmpty { title.caption() },
+                style = MaterialTheme.typography.bodySmall,
+                color = Color.White.copy(alpha = 0.8f),
+            )
+            title.overview?.let {
+                Text(
+                    it.trim(),
+                    style = MaterialTheme.typography.bodySmall,
+                    color = Color.White.copy(alpha = 0.8f),
+                    maxLines = 3,
+                    overflow = TextOverflow.Ellipsis,
+                    modifier = Modifier.padding(top = 6.dp),
+                )
+            }
+            Row(horizontalArrangement = Arrangement.spacedBy(8.dp), modifier = Modifier.padding(top = 12.dp)) {
+                AccentButton(onClick = { onPlay(resume?.index ?: nextUpIndex(playlist, title.continueIndex)) }) {
+                    Icon(Icons.Default.PlayArrow, contentDescription = null)
+                    Spacer(Modifier.width(6.dp))
+                    Text(if (resume != null) "Resume" else "Play")
+                }
+                TonalButton(onClick = onOpen) { Text("More info") }
+            }
+        }
+    }
+}
+
+/** A part-watched episode: its still, where it was left, and what is left of it. */
+@Composable
+private fun ContinueCard(entry: Resumable, onClick: () -> Unit, onLongClick: () -> Unit) {
+    Column(
+        Modifier
+            .width(220.dp)
+            .clip(MaterialTheme.shapes.medium)
+            .combinedClickable(onClick = onClick, onLongClick = onLongClick, onLongClickLabel = "More for this episode"),
+    ) {
+        Box(Modifier.fillMaxWidth().aspectRatio(16f / 9f).clip(MaterialTheme.shapes.medium)) {
+            // Named by the text under it; read as well, the name came twice.
+            RemoteArtwork(
+                entry.episode.stillUrl ?: entry.title.backdropUrl,
+                entry.title.displayName,
+                Modifier.fillMaxSize().clearAndSetSemantics {},
+                fallback = entry.episode.thumbnailSource,
+                maxEdge = 220.dp,
+            )
+            entry.episode.progress?.let { progress ->
+                AccentProgress(
+                    progress = { progress.toFloat().coerceIn(0f, 1f) },
+                    modifier = Modifier.fillMaxWidth().align(Alignment.BottomCenter),
+                )
+            }
+        }
+        Text(
+            entry.title.displayName,
+            fontWeight = FontWeight.SemiBold,
+            maxLines = 1,
+            overflow = TextOverflow.Ellipsis,
+            modifier = Modifier.padding(top = 8.dp),
+        )
+        Text(
+            if (entry.episode.resumeAt == null) {
+                "Next: ${entry.episode.label}"
+            } else {
+                listOfNotNull(entry.episode.label, entry.episode.timeLeft()).joinToString(" · ")
+            },
+            style = MaterialTheme.typography.bodySmall,
+            color = MaterialTheme.colorScheme.onSurfaceVariant,
+            maxLines = 1,
+            overflow = TextOverflow.Ellipsis,
+        )
+    }
+}
+
+/**
+ * One title: its poster, and its name and size under it rather than in a card.
+ *
+ * [folded] is how many more titles of its franchise the tile stands for, said
+ * in the corner. [shared] is whether the poster grows into the title page —
+ * only one copy of a title on screen can, and a shelf may hold the same title
+ * as the grid.
+ */
+@Composable
+private fun PosterTile(
+    title: TitleRecord,
+    onClick: () -> Unit,
+    onLongClick: () -> Unit,
+    modifier: Modifier = Modifier,
+    folded: Int = 0,
+    shared: Boolean = true,
+) {
+    Column(
+        modifier
+            .clip(MaterialTheme.shapes.medium)
+            .combinedClickable(onClick = onClick, onLongClick = onLongClick, onLongClickLabel = "More for this title"),
+    ) {
+        Box {
+            RemoteArtwork(
+                title.posterUrl ?: title.backdropUrl,
+                title.displayName,
+                (if (shared) Modifier.sharedArt(title.key) else Modifier)
+                    .fillMaxWidth()
+                    .aspectRatio(2f / 3f)
+                    .clip(MaterialTheme.shapes.medium)
+                    .clearAndSetSemantics {},
+                fallback = title.thumbnailSource,
+                // The tile's height, at the widest a grid column gets.
+                maxEdge = 280.dp,
+            )
+            if (folded > 0) {
+                Text(
+                    "+$folded",
+                    style = MaterialTheme.typography.labelSmall,
+                    color = Color.White,
+                    modifier = Modifier
+                        .align(Alignment.TopEnd)
+                        .padding(6.dp)
+                        .clip(MaterialTheme.shapes.small)
+                        .background(Color.Black.copy(alpha = 0.7f))
+                        .padding(horizontal = 6.dp, vertical = 2.dp)
+                        .semantics { contentDescription = "and $folded more" },
+                )
+            }
+        }
+        Spacer(Modifier.height(6.dp))
+        Text(
+            title.displayName,
+            style = MaterialTheme.typography.bodyMedium,
+            fontWeight = FontWeight.SemiBold,
+            maxLines = 2,
+            overflow = TextOverflow.Ellipsis,
+        )
+        // Two lines, not one: at a large font scale "2023 · 7 episodes" does
+        // not fit a poster's width, and one line cut it to "2023 · 7".
+        Text(
+            title.caption(),
+            style = MaterialTheme.typography.bodySmall,
+            color = MaterialTheme.colorScheme.onSurfaceVariant,
+            maxLines = 2,
+            overflow = TextOverflow.Ellipsis,
+        )
+    }
+}
+
+/** "2023 · 11 episodes", or "1988 · Film" — never "1 episodes". */
+private fun TitleRecord.caption(): String = listOfNotNull(
+    (metadataYear ?: year)?.toString(),
+    when {
+        (metadataKind ?: kind) == TitleType.FILM && episodeCount == 1uL -> "Film"
+        episodeCount == 1uL -> "1 episode"
+        else -> "$episodeCount episodes"
+    },
+).joinToString(" · ")
+
+/**
+ * "12 min left", from where the episode was left and how far through that is.
+ * Null when either is unknown — a guess would be worse than no figure.
+ */
+private fun EpisodeRecord.timeLeft(): String? {
+    val at = resumeAt ?: return null
+    val fraction = progress?.takeIf { it > 0.0 && it < 1.0 } ?: return null
+    val minutes = ((at / fraction - at) / 60).toInt()
+    return if (minutes < 1) "under a minute left" else "$minutes min left"
+}

android/app/src/main/java/io/narl/protonstream/ui/RemoteArtwork.kt

@@ -1,10 +1,18 @@
 package io.narl.protonstream.ui
 
+import android.content.Context
+import android.graphics.Bitmap
 import android.graphics.BitmapFactory
+import android.util.LruCache
 import androidx.compose.foundation.Image
 import androidx.compose.foundation.background
+import androidx.compose.animation.core.RepeatMode
+import androidx.compose.animation.core.animateFloat
+import androidx.compose.animation.core.infiniteRepeatable
+import androidx.compose.animation.core.rememberInfiniteTransition
+import androidx.compose.animation.core.tween
 import androidx.compose.foundation.layout.Box
-import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.BoxWithConstraints
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
@@ -13,65 +21,330 @@ import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.setValue
+import androidx.compose.runtime.staticCompositionLocalOf
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Brush
+import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.ImageBitmap
+import androidx.compose.ui.graphics.graphicsLayer
+import androidx.compose.ui.graphics.lerp
 import androidx.compose.ui.graphics.asImageBitmap
 import androidx.compose.ui.layout.ContentScale
 import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.text.font.FontWeight
+import io.narl.protonstream.native.NativeRuntime
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
+import uniffi.pstr_android.EpisodeRecord
+import uniffi.pstr_android.TitleRecord
 import java.net.HttpURLConnection
 import java.net.URI
 import java.io.ByteArrayOutputStream
+import java.io.File
 import java.io.InputStream
 import java.security.MessageDigest
+import java.util.Collections
 
-/** HTTPS-only artwork loader backed by the app-private cache directory. */
+/**
+ * One file to pull Proton's own thumbnail from when no provider poster exists.
+ *
+ * Proton renders a thumbnail per file, so any episode of a show is a frame of
+ * the right show — the desktop client picks the first for the same reason.
+ */
+data class ThumbnailSource(val shareId: String, val volumeId: String, val linkId: String) {
+    val key: String get() = "$shareId/$linkId"
+}
+
+/**
+ * What the first episode of a title offers as a poster.
+ *
+ * Metadata lookups are off by default, so for a freshly crawled library this is
+ * the only artwork there is.
+ */
+internal val TitleRecord.thumbnailSource: ThumbnailSource?
+    get() = seasons.firstNotNullOfOrNull { season -> season.episodes.firstOrNull() }
+        ?.let { ThumbnailSource(it.shareId, it.volumeId, it.linkId) }
+
+/** What one episode offers as a still. */
+internal val EpisodeRecord.thumbnailSource: ThumbnailSource
+    get() = ThumbnailSource(shareId, volumeId, linkId)
+
+/**
+ * HTTPS-only artwork loader backed by the app-private cache directory.
+ *
+ * [fallback] is used only when there is no provider artwork or it fails to
+ * load, which — with metadata off — is the common case rather than the rare
+ * one. Until either answers, the box pulses as a skeleton; when neither has
+ * anything, it shows [ArtworkPlaceholder] rather than an empty card — without
+ * initials when [labelled] is false, for art with the name already over it.
+ */
 @Composable
-internal fun RemoteArtwork(url: String?, description: String, modifier: Modifier = Modifier) {
+internal fun RemoteArtwork(
+    url: String?,
+    description: String,
+    modifier: Modifier = Modifier,
+    fallback: ThumbnailSource? = null,
+    labelled: Boolean = true,
+    maxEdge: Dp? = null,
+) {
     val context = LocalContext.current
-    var image by remember(url) { mutableStateOf<ImageBitmap?>(null) }
+    val enabled = LocalArtworkLoading.current
-    LaunchedEffect(url) {
+    // Decoded at the size it is drawn: a grid tile is a few hundred pixels,
-        image = url?.let { requested ->
+    // and decoding its poster at 1024 holds four times the memory for nothing.
-            withContext(Dispatchers.IO) {
+    val edge = with(LocalDensity.current) { maxEdge?.roundToPx() }?.coerceIn(1, MAX_ART_EDGE) ?: MAX_ART_EDGE
-                runCatching {
+    var image by remember(url, fallback) { mutableStateOf<ArtworkLoad>(ArtworkLoad.Pending) }
-                    val uri = URI(requested)
+    LaunchedEffect(url, fallback, enabled) {
-                    require(uri.scheme.equals("https", ignoreCase = true)) { "Artwork must use HTTPS" }
+        if (!enabled) {
-                    val directory = context.cacheDir.resolve("metadata-art").apply { mkdirs() }
+            image = ArtworkLoad.Missing
-                    val digest = MessageDigest.getInstance("SHA-256")
+            return@LaunchedEffect
-                        .digest(requested.toByteArray()).joinToString("") { "%02x".format(it) }
-                    val cached = directory.resolve("$digest.img")
-                    val bytes = if (cached.isFile) cached.readBytes() else {
-                        val connection = uri.toURL().openConnection() as HttpURLConnection
-                        connection.connectTimeout = 10_000
-                        connection.readTimeout = 10_000
-                        connection.instanceFollowRedirects = true
-                        val status = connection.responseCode
-                        require(status in 200..299) { "Artwork request failed ($status)" }
-                        require(connection.url.protocol.equals("https", ignoreCase = true)) {
-                            "Artwork redirect must use HTTPS"
-                        }
-                        connection.inputStream.use(::readBounded).also { downloaded ->
-                            require(downloaded.size <= MAX_ART_BYTES) { "Artwork is too large" }
-                            val temporary = directory.resolve("$digest.part")
-                            temporary.writeBytes(downloaded)
-                            check(temporary.renameTo(cached)) { "Unable to cache artwork" }
-                        }
-                    }
-                    BitmapFactory.decodeByteArray(bytes, 0, bytes.size)?.asImageBitmap()
-                }.getOrNull()
-            }
         }
+        image = (loadArtwork(context, url, edge) ?: loadThumbnail(fallback, edge))
+            ?.let { ArtworkLoad.Loaded(it.asImageBitmap()) }
+            ?: ArtworkLoad.Missing
     }
-    Box(modifier.background(MaterialTheme.colorScheme.surfaceVariant), contentAlignment = Alignment.Center) {
+    when (val loaded = image) {
-        image?.let {
+        ArtworkLoad.Pending -> Skeleton(modifier)
-            Image(it, description, Modifier.fillMaxSize(), contentScale = ContentScale.Crop)
+        ArtworkLoad.Missing -> ArtworkPlaceholder(description, modifier, labelled)
-        } ?: Text("▶", style = MaterialTheme.typography.displaySmall)
+        is ArtworkLoad.Loaded -> Image(loaded.image, description, modifier, contentScale = ContentScale.Crop)
     }
 }
 
+private sealed interface ArtworkLoad {
+    data object Pending : ArtworkLoad
+    data object Missing : ArtworkLoad
+    data class Loaded(val image: ImageBitmap) : ArtworkLoad
+}
+
+/**
+ * Whether [RemoteArtwork] fetches anything at all.
+ *
+ * Off in the screenshot tests: there is no bridge on the host, and whether a
+ * failed fetch lands before or after the capture would decide between a
+ * skeleton and a placeholder in the committed image.
+ */
+internal val LocalArtworkLoading = staticCompositionLocalOf { true }
+
+/**
+ * Something being loaded: the surface tint, breathing.
+ *
+ * A spinner per tile is a grid of spinners; a shape where the poster will be
+ * says what is coming and where, and settles the layout before it arrives.
+ */
+@Composable
+internal fun Skeleton(modifier: Modifier = Modifier) {
+    val pulse by rememberInfiniteTransition(label = "skeleton").animateFloat(
+        initialValue = 0.55f,
+        targetValue = 1f,
+        animationSpec = infiniteRepeatable(tween(800), RepeatMode.Reverse),
+        label = "skeleton alpha",
+    )
+    Box(modifier.graphicsLayer { alpha = pulse }.background(MaterialTheme.colorScheme.surfaceVariant))
+}
+
+/**
+ * Art for a title that has none: the accent as a gradient, and its initials.
+ *
+ * A black card with a play triangle on it said nothing about which title it
+ * was, so a grid of unmatched titles was a grid of identical cards. Each name
+ * sets where on the accent ramp its gradient starts, so neighbours differ
+ * while every one stays in the theme's colours.
+ */
+@Composable
+internal fun ArtworkPlaceholder(name: String, modifier: Modifier = Modifier, labelled: Boolean = true) {
+    val scheme = MaterialTheme.colorScheme
+    val brush = remember(name, scheme.primary, scheme.secondary) {
+        val start = lerp(scheme.primary, scheme.secondary, (name.hashCode().mod(5)) / 4f)
+        Brush.linearGradient(listOf(start, lerp(start, Color.Black, 0.55f)))
+    }
+    BoxWithConstraints(modifier.background(brush), contentAlignment = Alignment.Center) {
+        if (!labelled) return@BoxWithConstraints
+        val size = with(LocalDensity.current) { (minOf(maxWidth, maxHeight) * 0.3f).toSp() }
+        Text(
+            initials(name),
+            color = Color.White.copy(alpha = 0.9f),
+            fontSize = size,
+            fontWeight = FontWeight.SemiBold,
+            maxLines = 1,
+        )
+    }
+}
+
+/**
+ * "Oshi no Ko" is "OK", "Akira" is "A": the first letters of up to two
+ * capitalised words, so particles and articles in a romanised name do not
+ * take a slot. A name with no capitals uses its first two words.
+ */
+internal fun initials(name: String): String {
+    val words = name.split(' ', '-', '_', '.', ':').filter { word -> word.firstOrNull()?.isLetterOrDigit() == true }
+    val picked = words.filter { it.first().isUpperCase() || it.first().isDigit() }.ifEmpty { words }
+    return picked.take(2).joinToString("") { it.first().uppercase() }
+}
+
+/**
+ * The same HTTPS-only fetch behind the library grid, reusable off the composition.
+ *
+ * The media notification needs a bitmap rather than an [ImageBitmap], and needs
+ * it from a service with no composition of its own — but it wants exactly this
+ * loader's protocol checks and exactly this disk cache, so the artwork the shade
+ * shows costs no second download.
+ */
+internal suspend fun loadArtwork(context: Context, url: String?, edge: Int = MAX_ART_EDGE): Bitmap? = url?.let { requested ->
+    decoded.get(sized(requested, edge)) ?: withContext(Dispatchers.IO) {
+        runCatching {
+            val uri = URI(requested)
+            require(uri.scheme.equals("https", ignoreCase = true)) { "Artwork must use HTTPS" }
+            val directory = context.cacheDir.resolve("metadata-art").apply { mkdirs() }
+            val digest = MessageDigest.getInstance("SHA-256")
+                .digest(requested.toByteArray()).joinToString("") { "%02x".format(it) }
+            val cached = directory.resolve("$digest.img")
+            val fresh = !cached.isFile
+            val bytes = if (fresh) download(uri) else cached.readBytes()
+            val bitmap = requireNotNull(decodeSampled(bytes, edge)) { "Artwork is not a decodable image" }
+            if (fresh) {
+                // Written only once it has decoded. Caching the bytes first is
+                // what turns one hostile poster into a crash on every launch
+                // that survives until app data is cleared.
+                val temporary = directory.resolve("$digest.part")
+                temporary.writeBytes(bytes)
+                check(temporary.renameTo(cached)) { "Unable to cache artwork" }
+                prune(directory)
+            } else {
+                cached.setLastModified(System.currentTimeMillis())
+            }
+            bitmap
+        }.getOrNull()?.also { decoded.put(sized(requested, edge), it) }
+    }
+}
+
+/**
+ * Proton's own thumbnail for one file, decoded.
+ *
+ * The bridge holds the disk cache, so what is worth keeping here is the decoded
+ * bitmap and the *absence* of one: a file with no thumbnail is common, and
+ * without remembering that, every scroll back over the grid pays a round trip
+ * per tile to be told so again. A failed call is not remembered — an unreachable
+ * share or a session that has to be reopened is transient, and the next
+ * composition should try again.
+ */
+internal suspend fun loadThumbnail(source: ThumbnailSource?, edge: Int = MAX_ART_EDGE): Bitmap? {
+    val file = source ?: return null
+    val key = file.key
+    decoded.get(sized(key, edge))?.let { return it }
+    if (key in missing) return null
+    val fetched = withContext(Dispatchers.IO) {
+        runCatching { NativeRuntime.engine().thumbnail(file.shareId, file.volumeId, file.linkId) }
+    }
+    val bytes = fetched.getOrElse { return null }
+    val bitmap = bytes?.let { withContext(Dispatchers.Default) { decodeSampled(it, edge) } }
+    if (bitmap == null) {
+        missing.add(key)
+        return null
+    }
+    decoded.put(sized(key, edge), bitmap)
+    return bitmap
+}
+
+private fun download(uri: URI): ByteArray {
+    val connection = uri.toURL().openConnection() as HttpURLConnection
+    connection.connectTimeout = 10_000
+    connection.readTimeout = 10_000
+    connection.instanceFollowRedirects = true
+    val status = connection.responseCode
+    require(status in 200..299) { "Artwork request failed ($status)" }
+    require(connection.url.protocol.equals("https", ignoreCase = true)) {
+        "Artwork redirect must use HTTPS"
+    }
+    return connection.inputStream.use(::readBounded)
+        .also { require(it.size <= MAX_ART_BYTES) { "Artwork is too large" } }
+}
+
+/**
+ * Decode with its longest edge at most [edge] pixels.
+ *
+ * [MAX_ART_BYTES] bounds the *compressed* image, which says nothing about what
+ * it costs decoded: a 12 MiB PNG can be 12000×12000, and that is a 576 MB
+ * `ARGB_8888` allocation on a device that will not give it. The bounds pass
+ * costs no allocation and settles a sample size before anything is committed.
+ *
+ * Sampling halves, so it stops while the image is still at least [edge]; the
+ * decoder scales the rest of the way, which a poster sampled straight to under
+ * its tile would show as blur.
+ */
+private fun decodeSampled(bytes: ByteArray, edge: Int): Bitmap? {
+    val bounds = BitmapFactory.Options().apply { inJustDecodeBounds = true }
+    BitmapFactory.decodeByteArray(bytes, 0, bytes.size, bounds)
+    val longest = maxOf(bounds.outWidth, bounds.outHeight)
+    if (longest <= 0) return null
+    var sample = 1
+    while (longest / (sample * 2) >= edge) sample *= 2
+    val sampled = longest / sample
+    return BitmapFactory.decodeByteArray(
+        bytes,
+        0,
+        bytes.size,
+        BitmapFactory.Options().apply {
+            inSampleSize = sample
+            if (sampled > edge) {
+                inScaled = true
+                inDensity = sampled
+                inTargetDensity = edge
+            }
+        },
+    )
+}
+
+/** The decoded cache's key for one image at one size. */
+private fun sized(key: String, edge: Int) = "$key#$edge"
+
+/**
+ * Hold the cache directory under [MAX_ART_CACHE_BYTES], oldest first.
+ *
+ * `cacheDir` is reclaimable by the system, but only under storage pressure and
+ * only wholesale — a poster cache that grows with every title ever browsed is
+ * still the app's own doing.
+ */
+private fun prune(directory: File) {
+    val files = directory.listFiles()?.sortedBy(File::lastModified) ?: return
+    var total = files.sumOf(File::length)
+    for (file in files) {
+        if (total <= MAX_ART_CACHE_BYTES) return
+        total -= file.length()
+        file.delete()
+    }
+}
+
+/**
+ * Files known to have no Proton thumbnail, so the answer is paid for once.
+ *
+ * Deliberately not persisted: a re-upload can add one, and the cost of being
+ * wrong for a session is a placeholder that a restart clears.
+ */
+private val missing: MutableSet<String> = Collections.synchronizedSet(mutableSetOf())
+
+/**
+ * Decoded posters, so scrolling the grid re-reads neither disk nor decoder.
+ *
+ * Keyed by artwork URL or by `share/link` for a Proton thumbnail; the two
+ * cannot collide, since one is always an `https:` URL.
+ *
+ * `remember(url)` is per-composition, and a `LazyVerticalGrid` drops and
+ * recreates items as they leave the viewport — without this, every scroll back
+ * is a full-resolution decode per item.
+ */
+private val decoded = object : LruCache<String, Bitmap>(
+    (Runtime.getRuntime().maxMemory() / 8).coerceIn(4L * 1024 * 1024, 64L * 1024 * 1024).toInt(),
+) {
+    override fun sizeOf(key: String, value: Bitmap): Int = value.byteCount
+}
+
 private const val MAX_ART_BYTES = 12 * 1024 * 1024
+private const val MAX_ART_CACHE_BYTES = 48L * 1024 * 1024
+
+/** Longest edge worth decoding: a poster on a phone, or a notification icon. */
+private const val MAX_ART_EDGE = 1_024
 
 /** Reads at most [MAX_ART_BYTES] plus one byte without requiring API 33's readNBytes. */
 private fun readBounded(input: InputStream): ByteArray {

android/app/src/main/java/io/narl/protonstream/ui/SettingsScreen.kt

@@ -0,0 +1,658 @@
+package io.narl.protonstream.ui
+
+import androidx.activity.compose.BackHandler
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.ColumnScope
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.ArrowBack
+import androidx.compose.material.icons.automirrored.filled.ManageSearch
+import androidx.compose.material.icons.filled.Info
+import androidx.compose.material.icons.filled.Palette
+import androidx.compose.material.icons.filled.PlayCircle
+import androidx.compose.material.icons.filled.Storage
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.runtime.saveable.rememberSaveable
+import androidx.compose.ui.graphics.vector.ImageVector
+import androidx.compose.foundation.border
+import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.FlowRow
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.heightIn
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.LazyRow
+import androidx.compose.foundation.shape.CircleShape
+import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.lazy.grid.items
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.Switch
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.text.input.PasswordVisualTransformation
+import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.ui.text.input.KeyboardType
+import androidx.compose.ui.window.DialogProperties
+import androidx.compose.ui.window.SecureFlagPolicy
+import androidx.compose.ui.unit.dp
+import io.narl.protonstream.settings.SettingsStore
+import io.narl.protonstream.sync.NewEpisodesWorker
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+import io.narl.protonstream.download.DownloadCoordinator
+import io.narl.protonstream.native.NativeRuntime
+import io.narl.protonstream.ui.theme.AccentButton
+import io.narl.protonstream.ui.theme.DangerButton
+import io.narl.protonstream.ui.theme.AppearanceState
+import io.narl.protonstream.ui.theme.EdgedButton
+import io.narl.protonstream.ui.theme.TonalButton
+import uniffi.pstr_android.MetadataProvider
+import uniffi.pstr_android.FlavorChoice
+import uniffi.pstr_android.AppearanceRecord
+import uniffi.pstr_android.TitleNamesChoice
+import uniffi.pstr_android.AccentChoice
+import uniffi.pstr_android.PlaybackPrefsRecord
+import androidx.compose.material3.ListItem
+import androidx.compose.material3.ListItemDefaults
+import androidx.compose.material3.FilterChip
+import androidx.compose.foundation.selection.toggleable
+import androidx.compose.ui.semantics.Role
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.height
+import io.narl.protonstream.ui.theme.AccentProgress
+
+@Composable
+internal fun SettingsScreen(
+    state: AppUiState,
+    /** Resolves to why the settings were not stored, or null once they are. */
+    onSaveMetadata: suspend (Boolean, MetadataProvider, String, String) -> String?,
+    onMatchAgain: () -> Unit,
+    onClearCache: () -> Unit,
+    onRemoveAllOffline: () -> Unit,
+    padding: PaddingValues,
+    initialPage: SettingsPage? = null,
+    // A parameter so the screenshot tests can pin it: read from the package,
+    // every version bump changed the committed image of this page.
+    version: String = appVersion(),
+    /** The library's names changed, and it has to be read again to show them. */
+    onNamesChanged: () -> Unit = {},
+) {
+    val context = LocalContext.current
+    val settings = remember { SettingsStore(context) }
+    var wifiOnly by remember { mutableStateOf(settings.wifiOnly) }
+    var backgroundAudio by remember { mutableStateOf(settings.backgroundAudio) }
+    var newEpisodes by remember { mutableStateOf(settings.newEpisodeNotifications) }
+    var hardwareDecoding by remember { mutableStateOf(settings.hardwareDecoding) }
+    var cacheBudgetGib by remember { mutableStateOf(settings.cacheBudgetGib) }
+    // Playback preferences are the shared store's, not this app's: they are the
+    // same file the desktop client reads, so a language chosen on one is the
+    // language the other starts in.
+    var prefs by remember { mutableStateOf<PlaybackPrefsRecord?>(null) }
+    val scope = rememberCoroutineScope()
+    fun update(change: (PlaybackPrefsRecord) -> PlaybackPrefsRecord) {
+        val next = change(prefs ?: return)
+        prefs = next
+        scope.launch(Dispatchers.IO) {
+            runCatching { NativeRuntime.engine().setPlaybackPrefs(next) }
+        }
+    }
+    LaunchedEffect(Unit) {
+        runCatching { withContext(Dispatchers.IO) { NativeRuntime.engine().playbackPrefs() } }
+            .onSuccess { prefs = it }
+    }
+    var confirmDelete by remember { mutableStateOf(false) }
+    var showMetadata by remember { mutableStateOf(false) }
+    var legalDocument by remember { mutableStateOf<LegalDocument?>(null) }
+    // One row per area on the first page, each opening its own page: grouped
+    // on one page, the storage controls sat a long scroll below playback, and
+    // every setting added made the rest harder to find.
+    var page by rememberSaveable { mutableStateOf(initialPage) }
+    BackHandler(enabled = page != null) { page = null }
+    val back: @Composable () -> Unit = {
+        IconButton(onClick = { page = null }) {
+            Icon(Icons.AutoMirrored.Filled.ArrowBack, contentDescription = "Back to settings")
+        }
+    }
+    when (page) {
+        null -> TabPage("Settings", padding) { body ->
+            Column(Modifier.fillMaxSize().padding(body).verticalScroll(rememberScrollState())) {
+                SettingsPage.entries.forEach { entry ->
+                    ListItem(
+                        headlineContent = { Text(entry.title) },
+                        supportingContent = {
+                            Text(
+                                when (entry) {
+                                    SettingsPage.Playback -> "Autoplay, languages and decoding"
+                                    SettingsPage.Storage -> "${formatBytes(state.storage.cacheBytes)} cached · " +
+                                        "${state.storage.offlineCount} offline"
+                                    SettingsPage.Appearance -> "Palette, accent and gradient"
+                                    SettingsPage.Metadata -> if (state.metadataSettings.enabled) {
+                                        "On · ${state.metadataSettings.provider.displayName()}"
+                                    } else {
+                                        "Off"
+                                    }
+                                    SettingsPage.About -> "Version $version · licences"
+                                },
+                            )
+                        },
+                        leadingContent = { Icon(entry.icon, contentDescription = null) },
+                        colors = ListItemDefaults.colors(containerColor = Color.Transparent),
+                        modifier = Modifier.clickable { page = entry },
+                    )
+                }
+            }
+        }
+        SettingsPage.Playback -> SettingsSubPage(SettingsPage.Playback, padding, back) {
+            prefs?.let { current ->
+                SettingSwitch(
+                    "Autoplay next episode",
+                    "Starts the next episode when the credits begin",
+                    current.autoplayNext,
+                ) { on -> update { it.copy(autoplayNext = on) } }
+                // Off is the safer default: a mis-named chapter then costs a tap on
+                // Skip rather than a scene.
+                SettingSwitch(
+                    "Skip openings and endings",
+                    "Uses the release's chapters; off shows a Skip button instead",
+                    current.autoSkip,
+                ) { on -> update { it.copy(autoSkip = on) } }
+                SettingSwitch("Subtitles", "Shown by default where a file has them", current.subtitles) { on ->
+                    update { it.copy(subtitles = on) }
+                }
+                // Preferences, not filters: a file with nothing in the language
+                // plays its own default track. A show that has been given its
+                // own choice keeps it.
+                LanguageSetting("Audio language", current.audioLanguage) { tag ->
+                    update { it.copy(audioLanguage = tag) }
+                }
+                LanguageSetting("Subtitle language", current.subtitleLanguage) { tag ->
+                    update { it.copy(subtitleLanguage = tag) }
+                }
+            }
+            SettingSwitch(
+                "Hardware decoding",
+                "Turn off if video shows green or torn frames",
+                hardwareDecoding,
+            ) {
+                hardwareDecoding = it
+                settings.hardwareDecoding = it
+            }
+            SettingSwitch(
+                "Background audio",
+                "Keeps playing with the app closed, from the notification",
+                backgroundAudio,
+            ) {
+                backgroundAudio = it
+                settings.backgroundAudio = it
+            }
+            SettingSwitch(
+                "New episode notifications",
+                "Looks at your shares every few hours and says when a show gains episodes",
+                newEpisodes,
+            ) {
+                newEpisodes = it
+                settings.newEpisodeNotifications = it
+                NewEpisodesWorker.schedule(context)
+            }
+        }
+        SettingsPage.Storage -> SettingsSubPage(SettingsPage.Storage, padding, back) {
+            SettingSwitch("Download on Wi-Fi only", "Mobile data is never used for downloads", wifiOnly) {
+                wifiOnly = it
+                settings.wifiOnly = it
+                // Constraints are baked in at enqueue time, so a queue that already
+                // exists keeps the policy it was queued under until it is re-issued.
+                DownloadCoordinator.applyNetworkPolicy(context)
+            }
+            Column(Modifier.padding(horizontal = 16.dp, vertical = 8.dp)) {
+                Text("Streaming cache")
+                Text(
+                    "${formatBytes(state.storage.cacheBytes)} of $cacheBudgetGib GiB used",
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                )
+                AccentProgress(
+                    progress = {
+                        (state.storage.cacheBytes.toDouble() / SettingsStore.gibToBytes(cacheBudgetGib).toDouble())
+                            .toFloat().coerceIn(0f, 1f)
+                    },
+                    modifier = Modifier.fillMaxWidth().padding(vertical = 8.dp),
+                )
+                // What has been watched is kept up to this much, so going back over
+                // a scene costs no download. A lower choice frees the difference at
+                // once. Wrapping, so five chips survive a narrow phone at a large
+                // font scale.
+                FlowRow(horizontalArrangement = Arrangement.spacedBy(8.dp)) {
+                    SettingsStore.CACHE_BUDGET_CHOICES.forEach { gib ->
+                        FilterChip(
+                            selected = gib == cacheBudgetGib,
+                            onClick = {
+                                cacheBudgetGib = gib
+                                settings.cacheBudgetGib = gib
+                                scope.launch(Dispatchers.IO) {
+                                    runCatching {
+                                        NativeRuntime.engine().setStreamCacheBudget(SettingsStore.gibToBytes(gib))
+                                    }
+                                }
+                            },
+                            label = { Text("$gib GiB") },
+                        )
+                    }
+                }
+            }
+            // The cache is rebuildable, so it goes without asking. Offline episodes
+            // are a choice the viewer made, so that one asks.
+            SettingAction("Clear streaming cache", "Frees ${formatBytes(state.storage.cacheBytes)}", onClick = onClearCache)
+            SettingAction(
+                "Delete all offline episodes",
+                "${state.storage.offlineCount} " + (if (state.storage.offlineCount == 1uL) "episode" else "episodes") +
+                    " · ${formatBytes(state.storage.offlineBytes)}" +
+                    (
+                        state.storage.partialBytes.takeIf { it > 0uL }
+                            ?.let { " · ${formatBytes(it)} unfinished" }
+                            .orEmpty()
+                        ),
+                enabled = state.storage.offlineCount > 0uL || state.storage.partialBytes > 0uL,
+                onClick = { confirmDelete = true },
+            )
+        }
+        SettingsPage.Appearance -> SettingsSubPage(SettingsPage.Appearance, padding, back) {
+            Column(Modifier.padding(horizontal = 16.dp)) { AppearancePicker(onNamesChanged) }
+        }
+        SettingsPage.Metadata -> SettingsSubPage(SettingsPage.Metadata, padding, back) {
+            SettingAction(
+                "Metadata enrichment",
+                if (state.metadataSettings.enabled) {
+                    "On · ${state.metadataSettings.provider.displayName()} · sends title names to it"
+                } else {
+                    "Off, the privacy default"
+                },
+                onClick = { showMetadata = true },
+            )
+            // Every title looked up again, matched ones included: the way out of a
+            // library the provider answered wrong, which otherwise stays wrong for
+            // as long as the match is remembered.
+            SettingAction(
+                "Match everything again",
+                "Looks every title up again, hand-picked matches excepted",
+                enabled = state.metadataSettings.enabled && !state.refreshing,
+                onClick = onMatchAgain,
+            )
+        }
+        SettingsPage.About -> SettingsSubPage(SettingsPage.About, padding, back) {
+            ListItem(
+                headlineContent = { Text("Proton Stream") },
+                supportingContent = { Text("Version $version") },
+                colors = ListItemDefaults.colors(containerColor = Color.Transparent),
+            )
+            SettingAction("Licence", "GPL-3.0-or-later. Comes with absolutely no warranty.") {
+                legalDocument = LegalDocument("GNU GPL v3", "licenses/GPL-3.0.txt")
+            }
+            SettingAction("Third-party notices", "libmpv, Inter and the other components bundled") {
+                legalDocument = LegalDocument("Third-party notices", "licenses/THIRD_PARTY_NOTICES.md")
+            }
+        }
+    }
+    if (confirmDelete) {
+        AlertDialog(
+            onDismissRequest = { confirmDelete = false },
+            title = { Text("Delete all offline episodes?") },
+            text = {
+                Text(
+                    "${state.storage.offlineCount} episodes (${formatBytes(state.storage.offlineBytes)}) " +
+                        "will be removed from this device. Watch history is kept, and anything " +
+                        "deleted can be downloaded again.",
+                )
+            },
+            confirmButton = {
+                DangerButton(onClick = { confirmDelete = false; onRemoveAllOffline() }) { Text("Delete") }
+            },
+            dismissButton = { TonalButton(onClick = { confirmDelete = false }) { Text("Cancel") } },
+        )
+    }
+    legalDocument?.let { document ->
+        LegalDocumentDialog(document, onDismiss = { legalDocument = null })
+    }
+    if (showMetadata) {
+        MetadataSettingsDialog(
+            current = state.metadataSettings,
+            onDismiss = { showMetadata = false },
+            onSave = onSaveMetadata,
+        )
+    }
+}
+
+/** The areas the first page lists, each a page of its own. */
+internal enum class SettingsPage(val title: String, val icon: ImageVector) {
+    Playback("Playback", Icons.Default.PlayCircle),
+    Storage("Downloads and storage", Icons.Default.Storage),
+    Appearance("Appearance", Icons.Default.Palette),
+    Metadata("Metadata", Icons.AutoMirrored.Filled.ManageSearch),
+    About("About", Icons.Default.Info),
+}
+
+/** One area's page: its name, a way back, and its rows. */
+@Composable
+private fun SettingsSubPage(
+    page: SettingsPage,
+    padding: PaddingValues,
+    back: @Composable () -> Unit,
+    rows: @Composable ColumnScope.() -> Unit,
+) {
+    TabPage(page.title, padding, navigationIcon = back) { body ->
+        Column(Modifier.fillMaxSize().padding(body).verticalScroll(rememberScrollState())) {
+            rows()
+            Spacer(Modifier.height(24.dp))
+        }
+    }
+}
+
+/** The installed version, as the launcher and the store show it. */
+@Composable
+private fun appVersion(): String {
+    val context = LocalContext.current
+    return remember {
+        runCatching { context.packageManager.getPackageInfo(context.packageName, 0).versionName }
+            .getOrNull() ?: "unknown"
+    }
+}
+
+/** A switch with its one line of explanation; the whole row toggles it. */
+@Composable
+private fun SettingSwitch(headline: String, supporting: String, checked: Boolean, onChecked: (Boolean) -> Unit) {
+    ListItem(
+        headlineContent = { Text(headline) },
+        supportingContent = { Text(supporting) },
+        trailingContent = { Switch(checked = checked, onCheckedChange = null) },
+        colors = ListItemDefaults.colors(containerColor = Color.Transparent),
+        modifier = Modifier.toggleable(value = checked, role = Role.Switch, onValueChange = onChecked),
+    )
+}
+
+/** A row that does something when tapped: opens a dialog, clears a cache. */
+@Composable
+private fun SettingAction(
+    headline: String,
+    supporting: String,
+    enabled: Boolean = true,
+    onClick: () -> Unit,
+) {
+    val colors = ListItemDefaults.colors(containerColor = Color.Transparent)
+    ListItem(
+        headlineContent = { Text(headline) },
+        supportingContent = { Text(supporting) },
+        colors = if (enabled) {
+            colors
+        } else {
+            ListItemDefaults.colors(
+                containerColor = Color.Transparent,
+                headlineColor = MaterialTheme.colorScheme.onSurface.copy(alpha = 0.38f),
+                supportingColor = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.38f),
+            )
+        },
+        modifier = Modifier.clickable(enabled = enabled, onClick = onClick),
+    )
+}
+
+@Composable
+private fun MetadataSettingsDialog(
+    current: uniffi.pstr_android.MetadataSettingsRecord,
+    onDismiss: () -> Unit,
+    onSave: suspend (Boolean, MetadataProvider, String, String) -> String?,
+) {
+    var enabled by remember { mutableStateOf(current.enabled) }
+    var provider by remember { mutableStateOf(current.provider) }
+    var language by remember { mutableStateOf(current.language) }
+    var apiKey by remember { mutableStateOf("") }
+    var saving by remember { mutableStateOf(false) }
+    var refusal by remember { mutableStateOf<String?>(null) }
+    val scope = rememberCoroutineScope()
+    val needsKey = enabled && provider == MetadataProvider.TMDB && !current.ready && apiKey.isBlank()
+    val forgets = current.enabled && (!enabled || provider != current.provider)
+    AlertDialog(
+        onDismissRequest = { if (!saving) onDismiss() },
+        properties = DialogProperties(securePolicy = SecureFlagPolicy.SecureOn),
+        title = { Text("Metadata enrichment") },
+        text = {
+            Column(verticalArrangement = Arrangement.spacedBy(8.dp)) {
+                Text("Off by default: enabling sends the titles in your library to a third party, associated with your IP address and subject to their privacy policy. With AniList, the matched ids also go to ani.zip for episode names and wide artwork.")
+                SettingToggle("Enable enrichment", enabled) { enabled = it }
+                Row(horizontalArrangement = Arrangement.spacedBy(8.dp)) {
+                    MetadataProvider.entries.forEach { option ->
+                        if (option == provider) AccentButton(onClick = { provider = option }) { Text(option.displayName()) }
+                        else EdgedButton(onClick = { provider = option }) { Text(option.displayName()) }
+                    }
+                }
+                Text(
+                    if (provider == MetadataProvider.ANI_LIST) "Anime; no account or API key required."
+                    else "Film and television; requires a free TMDB API key.",
+                    style = MaterialTheme.typography.bodySmall,
+                )
+                if (provider == MetadataProvider.TMDB) {
+                    OutlinedTextField(language, { language = it }, label = { Text("Language") }, singleLine = true)
+                    OutlinedTextField(
+                        apiKey,
+                        { apiKey = it },
+                        label = { Text(if (current.ready) "TMDB API key (leave blank to keep)" else "TMDB API key") },
+                        visualTransformation = PasswordVisualTransformation(),
+                        keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Password),
+                        singleLine = true,
+                    )
+                }
+                if (needsKey) Text("Enter a TMDB API key to save.", color = MaterialTheme.colorScheme.error)
+                // Said before Save rather than after: what is forgotten
+                // includes matches chosen by hand, which no look-up redoes.
+                if (forgets) {
+                    Text(
+                        "Saving forgets every poster, description and match stored now, " +
+                            "including ones you chose by hand.",
+                        color = MaterialTheme.colorScheme.error,
+                        style = MaterialTheme.typography.bodySmall,
+                    )
+                }
+                refusal?.let { Text(it, color = MaterialTheme.colorScheme.error) }
+            }
+        },
+        confirmButton = {
+            AccentButton(
+                enabled = !needsKey && !saving,
+                onClick = {
+                    saving = true
+                    refusal = null
+                    scope.launch {
+                        refusal = onSave(enabled, provider, language.ifBlank { "en" }, apiKey)
+                        saving = false
+                        if (refusal == null) onDismiss()
+                    }
+                },
+            ) { Text(if (saving) "Saving…" else "Save") }
+        },
+        dismissButton = { TonalButton(onClick = onDismiss, enabled = !saving) { Text("Cancel") } },
+    )
+}
+
+internal fun MetadataProvider.displayName(): String = when (this) {
+    MetadataProvider.ANI_LIST -> "AniList"
+    MetadataProvider.TMDB -> "TMDB"
+}
+
+private data class LegalDocument(val title: String, val assetPath: String)
+
+@Composable
+private fun LegalDocumentDialog(document: LegalDocument, onDismiss: () -> Unit) {
+    val context = LocalContext.current
+    var contents by remember(document.assetPath) { mutableStateOf("Loading…") }
+    LaunchedEffect(document.assetPath) {
+        contents = runCatching {
+            withContext(Dispatchers.IO) {
+                context.assets.open(document.assetPath).bufferedReader().use { it.readText() }
+            }
+        }.getOrElse { error -> "Unable to load this document: ${error.message}" }
+    }
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        title = { Text(document.title) },
+        text = {
+            LazyColumn(Modifier.fillMaxWidth().heightIn(max = 520.dp)) {
+                item { Text(contents, style = MaterialTheme.typography.bodySmall) }
+            }
+        },
+        confirmButton = { AccentButton(onClick = onDismiss) { Text("Close") } },
+    )
+}
+
+@Composable
+internal fun SettingToggle(label: String, checked: Boolean, onChecked: (Boolean) -> Unit) {
+    Row(Modifier.fillMaxWidth().padding(vertical = 14.dp), verticalAlignment = Alignment.CenterVertically) {
+        Text(label, Modifier.weight(1f))
+        Switch(checked = checked, onCheckedChange = onChecked)
+    }
+}
+
+/**
+ * Flavour, accent and gradients — the same three the desktop client offers.
+ *
+ * Every colour is resolved by Rust, so a swatch here is the colour the app will
+ * actually paint rather than an approximation of it, and the choice is stored in
+ * the file both clients read.
+ */
+@Composable
+private fun AppearancePicker(onNamesChanged: () -> Unit) {
+    val scope = rememberCoroutineScope()
+    var choice by remember { mutableStateOf<AppearanceRecord?>(null) }
+    var swatches by remember { mutableStateOf<Map<AccentChoice, Color>>(emptyMap()) }
+
+    suspend fun repaint(next: AppearanceRecord, store: Boolean) {
+        runCatching {
+            withContext(Dispatchers.IO) {
+                val engine = NativeRuntime.engine()
+                if (store) engine.setAppearance(next)
+                val palette = engine.previewPalette(next)
+                // Every accent as it would look in *this* flavour: a swatch row
+                // that keeps Mocha's pastels while Latte is selected is a row
+                // that lies about what the next tap does.
+                val row = AccentChoice.entries.associateWith { accent ->
+                    Color(engine.previewPalette(next.copy(accent = accent)).accent.toInt())
+                }
+                palette to row
+            }
+        }.onSuccess { (palette, row) ->
+            choice = next
+            swatches = row
+            AppearanceState.apply(palette)
+        }
+    }
+
+    LaunchedEffect(Unit) {
+        runCatching { withContext(Dispatchers.IO) { NativeRuntime.engine().appearance() } }
+            .onSuccess { repaint(it, store = false) }
+    }
+
+    val current = choice ?: return
+    Text("Palette", style = MaterialTheme.typography.bodyMedium, modifier = Modifier.padding(top = 8.dp))
+    LazyRow(horizontalArrangement = Arrangement.spacedBy(8.dp), modifier = Modifier.padding(vertical = 8.dp)) {
+        items(FlavorChoice.entries.toList(), key = { it.name }) { flavor ->
+            val selected = flavor == current.flavor
+            if (selected) {
+                AccentButton(onClick = {}) { Text(flavor.label()) }
+            } else {
+                EdgedButton(onClick = {
+                    scope.launch { repaint(current.copy(flavor = flavor), store = true) }
+                }) { Text(flavor.label()) }
+            }
+        }
+    }
+    Text("Accent", style = MaterialTheme.typography.bodyMedium)
+    LazyRow(horizontalArrangement = Arrangement.spacedBy(10.dp), modifier = Modifier.padding(vertical = 8.dp)) {
+        items(AccentChoice.entries.toList(), key = { it.name }) { accent ->
+            val swatch = swatches[accent] ?: MaterialTheme.colorScheme.surfaceVariant
+            Box(
+                Modifier
+                    .size(36.dp)
+                    .clip(CircleShape)
+                    .background(swatch)
+                    .border(
+                        width = if (accent == current.accent) 3.dp else 1.dp,
+                        color = if (accent == current.accent) {
+                            MaterialTheme.colorScheme.onBackground
+                        } else {
+                            MaterialTheme.colorScheme.outline
+                        },
+                        shape = CircleShape,
+                    )
+                    .clickable {
+                        scope.launch { repaint(current.copy(accent = accent), store = true) }
+                    },
+            )
+        }
+    }
+    Text("Title names", style = MaterialTheme.typography.bodyMedium)
+    LazyRow(horizontalArrangement = Arrangement.spacedBy(8.dp), modifier = Modifier.padding(vertical = 8.dp)) {
+        items(TitleNamesChoice.entries.toList(), key = { it.name }) { names ->
+            if (names == current.names) {
+                AccentButton(onClick = {}) { Text(names.label()) }
+            } else {
+                EdgedButton(onClick = {
+                    scope.launch {
+                        repaint(current.copy(names = names), store = true)
+                        onNamesChanged()
+                    }
+                }) { Text(names.label()) }
+            }
+        }
+    }
+    Text(
+        "What a matched title is called. Its other names still find it in search.",
+        style = MaterialTheme.typography.bodySmall,
+        modifier = Modifier.padding(bottom = 8.dp),
+    )
+    SettingToggle("Paint the accent as a gradient", current.gradients) { on ->
+        scope.launch { repaint(current.copy(gradients = on), store = true) }
+    }
+    Text(
+        "Off is the safer setting on a panel that bands: a slow ramp across a wide bar " +
+            "shows every step it is drawn from, and flat is better than striped.",
+        style = MaterialTheme.typography.bodySmall,
+        modifier = Modifier.padding(bottom = 14.dp),
+    )
+}
+
+/** What each name setting is called. The desktop client says the same. */
+private fun TitleNamesChoice.label() = when (this) {
+    TitleNamesChoice.LIBRARY -> "As in the share"
+    TitleNamesChoice.ENGLISH -> "English"
+    TitleNamesChoice.ROMAJI -> "Romaji"
+}
+
+/** What each palette family is called. The desktop client says the same. */
+private fun FlavorChoice.label() = when (this) {
+    FlavorChoice.PROTON -> "Proton"
+    FlavorChoice.LATTE -> "Catppuccin Latte"
+    FlavorChoice.FRAPPE -> "Catppuccin Frappé"
+    FlavorChoice.MACCHIATO -> "Catppuccin Macchiato"
+    FlavorChoice.MOCHA -> "Catppuccin Mocha"
+    FlavorChoice.PERSONA5 -> "Persona 5"
+}

android/app/src/main/java/io/narl/protonstream/ui/SharesScreen.kt

@@ -0,0 +1,433 @@
+package io.narl.protonstream.ui
+
+import kotlinx.coroutines.launch
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.material3.CircularProgressIndicator
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.lazy.grid.items
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.Text
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Refresh
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.text.input.PasswordVisualTransformation
+import androidx.compose.ui.text.input.VisualTransformation
+import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.ui.text.input.KeyboardType
+import androidx.compose.ui.window.DialogProperties
+import androidx.compose.ui.window.SecureFlagPolicy
+import androidx.compose.ui.unit.dp
+import io.narl.protonstream.ui.theme.AccentButton
+import io.narl.protonstream.ui.theme.DangerButton
+import io.narl.protonstream.ui.theme.TonalButton
+import androidx.compose.material.icons.filled.Edit
+import uniffi.pstr_android.AccountState
+import uniffi.pstr_android.ShareRecord
+import androidx.compose.foundation.layout.Box
+import androidx.compose.material3.ExtendedFloatingActionButton
+import androidx.compose.material3.ListItem
+import androidx.compose.material3.ListItemDefaults
+import androidx.compose.material3.DropdownMenu
+import androidx.compose.material3.DropdownMenuItem
+import androidx.compose.material.icons.filled.Add
+import androidx.compose.material.icons.filled.MoreVert
+import androidx.compose.material.icons.filled.Key
+import androidx.compose.material.icons.filled.Delete
+import androidx.compose.material.icons.filled.FolderShared
+import androidx.compose.material.icons.filled.Visibility
+import androidx.compose.material.icons.filled.VisibilityOff
+import androidx.compose.ui.graphics.Color
+
+@Composable
+internal fun SharesScreen(
+    shares: List<ShareRecord>,
+    /** Resolves to why the link was refused, or null once it is added. */
+    onAdd: suspend (String, String, String?) -> String?,
+    onRepair: (String, String, String?) -> Unit,
+    onRefresh: (String) -> Unit,
+    onRemove: (String) -> Unit,
+    incomingLink: String?,
+    onIncomingLinkTaken: () -> Unit,
+    padding: PaddingValues,
+    account: AccountUiState = AccountUiState(),
+    accountActions: AccountActions? = null,
+    onRename: (String, String) -> Unit = { _, _ -> },
+) {
+    var showAdd by remember { mutableStateOf(false) }
+    var renaming by remember { mutableStateOf<ShareRecord?>(null) }
+    var signingIn by remember { mutableStateOf(false) }
+    var browsing by remember { mutableStateOf(false) }
+    var repairing by remember { mutableStateOf<ShareRecord?>(null) }
+    var removing by remember { mutableStateOf<ShareRecord?>(null) }
+    TabPage("Shares", padding) { body ->
+        Box(Modifier.fillMaxSize().padding(body)) {
+            if (shares.isEmpty() && account.state == null) {
+                EmptyState("No shares yet", "Add a Proton Drive public link to build your library.")
+            } else {
+                LazyColumn(contentPadding = PaddingValues(top = 8.dp, bottom = 96.dp)) {
+                    if (accountActions != null) {
+                        item(key = "account") {
+                            AccountCard(
+                                account,
+                                accountActions,
+                                onSignIn = { signingIn = true },
+                                onBrowse = { browsing = true },
+                            )
+                        }
+                    }
+                    if (shares.isEmpty()) {
+                        item(key = "empty") {
+                            Text(
+                                "No shares yet. Add a public link, or a folder of your Drive once signed in.",
+                                style = MaterialTheme.typography.bodyMedium,
+                                color = MaterialTheme.colorScheme.onSurfaceVariant,
+                                modifier = Modifier.padding(16.dp),
+                            )
+                        }
+                    }
+                    items(shares, key = { it.id }) { share ->
+                        ShareRow(
+                            share = share,
+                            onRefresh = { onRefresh(share.id) },
+                            onRepair = { repairing = share },
+                            onRemove = { removing = share },
+                            onRename = { renaming = share },
+                        )
+                    }
+                }
+            }
+            // Where a thumb is, and the one thing this page is for. The share
+            // sheet and a tapped link land in the same form.
+            ExtendedFloatingActionButton(
+                onClick = { showAdd = true },
+                icon = { Icon(Icons.Default.Add, contentDescription = null) },
+                text = { Text("Add share") },
+                containerColor = MaterialTheme.colorScheme.primary,
+                contentColor = MaterialTheme.colorScheme.onPrimary,
+                modifier = Modifier.align(Alignment.BottomEnd).padding(16.dp),
+            )
+        }
+    }
+    if (showAdd || incomingLink != null) {
+        AddShareDialog(
+            initialUrl = incomingLink.orEmpty(),
+            onDismiss = { showAdd = false; onIncomingLinkTaken() },
+            onAdd = onAdd,
+        )
+    }
+    if (accountActions != null && (signingIn || account.state == AccountState.SecondFactor ||
+            account.state == AccountState.MailboxPassword)
+    ) {
+        SignInDialog(account, accountActions, onDismiss = { signingIn = false })
+    }
+    if (accountActions != null && browsing) {
+        DriveBrowserDialog(accountActions, onDismiss = { browsing = false })
+    }
+    repairing?.let { share ->
+        RepairShareDialog(
+            share = share,
+            onDismiss = { repairing = null },
+            onRepair = { url, password -> onRepair(share.id, url, password) },
+        )
+    }
+    renaming?.let { share ->
+        var name by remember(share.id) { mutableStateOf(share.name) }
+        AlertDialog(
+            onDismissRequest = { renaming = null },
+            title = { Text("Rename ${share.name}") },
+            text = { OutlinedTextField(name, { name = it }, label = { Text("Name") }, singleLine = true) },
+            confirmButton = {
+                AccentButton(enabled = name.isNotBlank(), onClick = {
+                    renaming = null
+                    onRename(share.id, name.trim())
+                }) { Text("Save") }
+            },
+            dismissButton = { TonalButton(onClick = { renaming = null }) { Text("Cancel") } },
+        )
+    }
+    removing?.let { share ->
+        // Asked, because it cannot be undone: the link's secret and its
+        // offline files go. Watch positions stay (`Catalog::remove_share`).
+        AlertDialog(
+            onDismissRequest = { removing = null },
+            title = { Text("Remove ${share.name}?") },
+            text = {
+                Text(
+                    "Its titles leave the library and its offline episodes are deleted. " +
+                        "Watch progress is kept, so adding the link again picks up where you left off.",
+                )
+            },
+            confirmButton = {
+                DangerButton(onClick = { removing = null; onRemove(share.id) }) { Text("Remove") }
+            },
+            dismissButton = { TonalButton(onClick = { removing = null }) { Text("Cancel") } },
+        )
+    }
+}
+
+/**
+ * One share: its name, how it is unlocked, and its actions behind a menu.
+ *
+ * Three differently styled controls beside the name squeezed it into a column
+ * a word wide; one icon leaves the row its width.
+ */
+/** "120 files · crawled 2 h ago", or that it has not been yet. */
+internal fun crawlLine(share: ShareRecord, now: Long = System.currentTimeMillis() / 1_000): String {
+    val at = share.crawledAt ?: return "Not crawled yet"
+    val files = share.crawlFiles?.toLong()?.let { if (it == 1L) "1 file" else "$it files" }
+    return listOfNotNull(files, "crawled ${ago(at, now)}").joinToString(" · ")
+}
+
+/** "just now", "5 min ago", "3 h ago", "2 days ago" — the desktop's `ui::ago`. */
+internal fun ago(at: Long, now: Long): String {
+    val seconds = (now - at).coerceAtLeast(0)
+    return when {
+        seconds < 60 -> "just now"
+        seconds < 3_600 -> "${seconds / 60} min ago"
+        seconds < 86_400 -> "${seconds / 3_600} h ago"
+        seconds < 172_800 -> "1 day ago"
+        else -> "${seconds / 86_400} days ago"
+    }
+}
+
+@Composable
+private fun ShareRow(
+    share: ShareRecord,
+    onRefresh: () -> Unit,
+    onRepair: () -> Unit,
+    onRemove: () -> Unit,
+    onRename: () -> Unit = {},
+) {
+    var menu by remember { mutableStateOf(false) }
+    ListItem(
+        headlineContent = { Text(share.name, fontWeight = FontWeight.SemiBold) },
+        supportingContent = {
+            Column {
+                Text(
+                    when {
+                        share.fromAccount -> "Folder of your Drive"
+                        share.hasCustomPassword -> "Link and custom password"
+                        else -> "Public link"
+                    },
+                )
+                Text(crawlLine(share), style = MaterialTheme.typography.bodySmall)
+                // Until a crawl succeeds: a link revoked upstream otherwise
+                // just stops growing.
+                share.crawlError?.let {
+                    Text(
+                        "Last crawl failed: $it",
+                        color = MaterialTheme.colorScheme.error,
+                        style = MaterialTheme.typography.bodySmall,
+                        maxLines = 2,
+                        overflow = TextOverflow.Ellipsis,
+                    )
+                }
+            }
+        },
+        leadingContent = {
+            Icon(
+                Icons.Default.FolderShared,
+                contentDescription = null,
+                tint = MaterialTheme.colorScheme.primary,
+            )
+        },
+        trailingContent = {
+            Box {
+                IconButton(onClick = { menu = true }) {
+                    Icon(Icons.Default.MoreVert, contentDescription = "Actions for ${share.name}")
+                }
+                DropdownMenu(expanded = menu, onDismissRequest = { menu = false }) {
+                    // One share, not the library: a link that has just had files
+                    // added should not cost a walk of every other one.
+                    DropdownMenuItem(
+                        text = { Text("Refresh") },
+                        leadingIcon = { Icon(Icons.Default.Refresh, contentDescription = null) },
+                        onClick = { menu = false; onRefresh() },
+                    )
+                    DropdownMenuItem(
+                        text = { Text("Rename") },
+                        leadingIcon = { Icon(Icons.Default.Edit, contentDescription = null) },
+                        onClick = { menu = false; onRename() },
+                    )
+                    // Not a remove: a share whose secret has become unreadable
+                    // cannot be removed either, since removal deletes a secret
+                    // the store can no longer touch.
+                    if (!share.fromAccount) {
+                        DropdownMenuItem(
+                            text = { Text("Re-enter link") },
+                            leadingIcon = { Icon(Icons.Default.Key, contentDescription = null) },
+                            onClick = { menu = false; onRepair() },
+                        )
+                    }
+                    DropdownMenuItem(
+                        text = { Text("Remove") },
+                        leadingIcon = { Icon(Icons.Default.Delete, contentDescription = null) },
+                        onClick = { menu = false; onRemove() },
+                    )
+                }
+            }
+        },
+        colors = ListItemDefaults.colors(containerColor = Color.Transparent),
+    )
+}
+
+/**
+ * Re-enter the link for a share the app can no longer decrypt its secret for.
+ *
+ * It has to be the *same* link — a different token is a different share, and
+ * repointing this one at it would leave every catalog row and every offline file
+ * describing something that is not there. Rust enforces that; this only says so.
+ */
+@Composable
+private fun RepairShareDialog(
+    share: ShareRecord,
+    onDismiss: () -> Unit,
+    onRepair: (String, String?) -> Unit,
+) {
+    var url by remember { mutableStateOf("") }
+    var password by remember { mutableStateOf("") }
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        properties = DialogProperties(securePolicy = SecureFlagPolicy.SecureOn),
+        title = { Text("Re-enter link for ${share.name}") },
+        text = {
+            Column(verticalArrangement = Arrangement.spacedBy(8.dp)) {
+                Text(
+                    "The stored credentials for this share cannot be read — usually after a " +
+                        "screen-lock change or a device restore. Entering the same link again " +
+                        "restores access without losing the library or anything downloaded.",
+                    style = MaterialTheme.typography.bodySmall,
+                )
+                OutlinedTextField(
+                    url,
+                    { url = it },
+                    label = { Text("Public share URL") },
+                    singleLine = true,
+                    visualTransformation = PasswordVisualTransformation(),
+                    keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Password),
+                )
+                OutlinedTextField(
+                    password,
+                    { password = it },
+                    label = { Text("Custom password (optional)") },
+                    singleLine = true,
+                    visualTransformation = PasswordVisualTransformation(),
+                    keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Password),
+                )
+            }
+        },
+        confirmButton = {
+            AccentButton(
+                onClick = { onRepair(url.trim(), password); onDismiss() },
+                enabled = url.isNotBlank(),
+            ) { Text("Restore") }
+        },
+        dismissButton = { TonalButton(onClick = onDismiss) { Text("Cancel") } },
+    )
+}
+
+/**
+ * Add a link. The form stays up while the link is opened, and with the reason
+ * under it when the link is refused, so fixing a typo is a retry rather than
+ * starting over.
+ */
+@Composable
+private fun AddShareDialog(
+    initialUrl: String,
+    onDismiss: () -> Unit,
+    onAdd: suspend (String, String, String?) -> String?,
+) {
+    var name by remember { mutableStateOf("") }
+    var url by remember(initialUrl) { mutableStateOf(initialUrl) }
+    var showLink by remember { mutableStateOf(false) }
+    var password by remember { mutableStateOf("") }
+    var adding by remember { mutableStateOf(false) }
+    var refusal by remember { mutableStateOf<String?>(null) }
+    val scope = rememberCoroutineScope()
+    AlertDialog(
+        onDismissRequest = { if (!adding) onDismiss() },
+        properties = DialogProperties(securePolicy = SecureFlagPolicy.SecureOn),
+        title = { Text("Add Proton Drive share") },
+        text = {
+            Column(verticalArrangement = Arrangement.spacedBy(8.dp)) {
+                OutlinedTextField(
+                    url,
+                    { url = it },
+                    label = { Text("Share link") },
+                    singleLine = true,
+                    // The URL fragment is a secret. Password input disables
+                    // IME learning/suggestions while normal long-press paste
+                    // remains available; the eye shows what was pasted.
+                    visualTransformation = if (showLink) VisualTransformation.None else PasswordVisualTransformation(),
+                    keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Password),
+                    trailingIcon = {
+                        IconButton(onClick = { showLink = !showLink }) {
+                            Icon(
+                                if (showLink) Icons.Default.VisibilityOff else Icons.Default.Visibility,
+                                contentDescription = if (showLink) "Hide link" else "Show link",
+                            )
+                        }
+                    },
+                )
+                OutlinedTextField(
+                    name,
+                    { name = it },
+                    label = { Text("Name (optional)") },
+                    supportingText = { Text("Defaults to the shared folder's name") },
+                    singleLine = true,
+                )
+                OutlinedTextField(
+                    password,
+                    { password = it },
+                    label = { Text("Custom password (optional)") },
+                    singleLine = true,
+                    visualTransformation = PasswordVisualTransformation(),
+                    keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Password),
+                )
+                if (adding) {
+                    Row(horizontalArrangement = Arrangement.spacedBy(12.dp), verticalAlignment = Alignment.CenterVertically) {
+                        CircularProgressIndicator(Modifier.size(18.dp), strokeWidth = 2.dp)
+                        Text("Opening the link…")
+                    }
+                } else {
+                    refusal?.let { Text(it, color = MaterialTheme.colorScheme.error) }
+                }
+            }
+        },
+        confirmButton = {
+            AccentButton(
+                onClick = {
+                    adding = true
+                    refusal = null
+                    scope.launch {
+                        refusal = onAdd(name.trim(), url.trim(), password)
+                        adding = false
+                        if (refusal == null) onDismiss()
+                    }
+                },
+                enabled = url.isNotBlank() && !adding,
+            ) { Text(if (adding) "Adding…" else "Add") }
+        },
+        dismissButton = { TonalButton(onClick = onDismiss, enabled = !adding) { Text("Cancel") } },
+    )
+}

android/app/src/main/java/io/narl/protonstream/ui/TitleScreen.kt

@@ -0,0 +1,790 @@
+package io.narl.protonstream.ui
+
+import android.content.Intent
+import androidx.activity.compose.PredictiveBackHandler
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.runtime.mutableFloatStateOf
+import androidx.compose.ui.graphics.graphicsLayer
+import kotlin.coroutines.cancellation.CancellationException
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.combinedClickable
+import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.heightIn
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.BoxWithConstraints
+import androidx.compose.foundation.layout.statusBarsPadding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.layout.aspectRatio
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.shape.CircleShape
+import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.lazy.itemsIndexed
+import androidx.compose.foundation.lazy.grid.items
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.DropdownMenu
+import androidx.compose.material3.DropdownMenuItem
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.Text
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.CheckCircle
+import androidx.compose.material.icons.outlined.CheckCircle
+import androidx.compose.material.icons.filled.DoneAll
+import androidx.compose.material.icons.filled.Download
+import androidx.compose.material.icons.filled.Edit
+import androidx.compose.material.icons.filled.RemoveDone
+import androidx.compose.material.icons.filled.Pause
+import androidx.compose.material.icons.filled.PlayArrow
+import androidx.compose.material.icons.automirrored.filled.ArrowBack
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.produceState
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.runtime.setValue
+import androidx.compose.runtime.livedata.observeAsState
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.ui.unit.dp
+import androidx.core.net.toUri
+import androidx.work.WorkManager
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+import io.narl.protonstream.download.DownloadCoordinator
+import io.narl.protonstream.download.DownloadStateStore
+import io.narl.protonstream.download.RetainedDownload
+import io.narl.protonstream.native.NativeRuntime
+import io.narl.protonstream.ui.theme.AccentButton
+import io.narl.protonstream.ui.theme.DangerButton
+import io.narl.protonstream.ui.theme.AccentProgress
+import io.narl.protonstream.ui.theme.EdgedButton
+import io.narl.protonstream.ui.theme.QuietButton
+import io.narl.protonstream.ui.theme.TonalButton
+import io.narl.protonstream.ui.theme.solid
+import androidx.compose.foundation.border
+import uniffi.pstr_android.TitleRecord
+import uniffi.pstr_android.TitleType
+import uniffi.pstr_android.EpisodeRecord
+import uniffi.pstr_android.SeasonRecord
+import uniffi.pstr_android.MatchRecord
+import androidx.compose.foundation.lazy.LazyRow
+import androidx.compose.material3.FilterChip
+import androidx.compose.material.icons.filled.Replay
+import androidx.compose.material.icons.filled.DownloadDone
+import androidx.compose.material.icons.automirrored.filled.OpenInNew
+import androidx.compose.ui.graphics.Brush
+import androidx.compose.ui.graphics.vector.ImageVector
+
+@Composable
+internal fun TitleScreen(
+    title: TitleRecord,
+    playerReady: Boolean,
+    onPlay: (List<EpisodeRecord>, Int) -> Unit,
+    onBack: () -> Unit,
+    onPreferenceError: (Throwable) -> Unit,
+    onMetadataChanged: () -> Unit,
+    onSetWatched: (EpisodeRecord, Boolean) -> Unit,
+    padding: PaddingValues,
+    /** Several episodes seen or unseen at once, named for the message. */
+    onMarkEpisodes: (List<EpisodeRecord>, Boolean, String) -> Unit = { _, _, _ -> },
+    /** Every title of its franchise, in release order, this one included. */
+    franchise: List<TitleRecord> = emptyList(),
+    onOpenTitle: (TitleRecord) -> Unit = {},
+) {
+    val context = LocalContext.current
+    val download = rememberDownload()
+    var showMatch by remember(title.key) { mutableStateOf(false) }
+    var overviewOpen by remember(title.key) { mutableStateOf(false) }
+
+    // Predictive back: the page shrinks towards the library as the gesture
+    // is dragged, and springs back if it is let go of, so the viewer sees
+    // where back goes before committing to it.
+    var backProgress by remember { mutableFloatStateOf(0f) }
+    PredictiveBackHandler { gesture ->
+        try {
+            gesture.collect { backProgress = it.progress }
+            onBack()
+        } catch (cancelled: CancellationException) {
+            backProgress = 0f
+            throw cancelled
+        }
+    }
+
+    // Display order across seasons: what previous/next and autoplay walk, and
+    // the same order the desktop client uses.
+    val playlist = remember(title) { title.seasons.flatMap(SeasonRecord::episodes) }
+    val nextUp = remember(playlist) { nextUpIndex(playlist, title.continueIndex) }
+    val upNext = playlist.getOrNull(nextUp)
+    // One season on screen at a time, opened on the one Play would land in: a
+    // forty-episode show as stacked sections is one long scroll to the part
+    // that matters.
+    var seasonIndex by remember(title.key) {
+        mutableStateOf(
+            title.seasons.indexOfFirst { season -> season.episodes.any { it.linkId == upNext?.linkId } }
+                .coerceAtLeast(0),
+        )
+    }
+    val season = title.seasons.getOrNull(seasonIndex)
+    // Live download state per episode, so a row can show progress and be paused
+    // without a trip to the Downloads tab.
+    val work by WorkManager.getInstance(context)
+        .getWorkInfosByTagLiveData(DownloadCoordinator.TAG).observeAsState(emptyList())
+    // Decoded off the main thread: WorkManager reports progress several times
+    // a second while a season downloads, and each report re-reads every record.
+    val downloads by produceState(emptyList<RetainedDownload>(), work) {
+        value = withContext(Dispatchers.IO) { DownloadStateStore(context).records() }
+    }
+
+    // On a tablet the page keeps a phone's reading width, centred: a Play
+    // button and synopsis lines two thousand pixels wide are read by turning
+    // the head. The backdrop still spans the window, but no taller than about
+    // half of it, or a landscape tablet opened on a picture and nothing else.
+    BoxWithConstraints(
+        Modifier
+            .fillMaxSize()
+            .graphicsLayer {
+                val scale = 1f - 0.1f * backProgress
+                scaleX = scale
+                scaleY = scale
+                shape = RoundedCornerShape((32 * backProgress).dp)
+                clip = backProgress > 0f
+            }
+            .padding(padding),
+    ) {
+        val side = ((maxWidth - READABLE_WIDTH) / 2).coerceAtLeast(0.dp)
+        val backdropHeight = minOf(maxWidth * 9f / 16f, maxHeight * 0.55f)
+        LazyColumn(
+            modifier = Modifier.fillMaxSize(),
+            contentPadding = PaddingValues(bottom = 24.dp),
+            verticalArrangement = Arrangement.spacedBy(8.dp),
+        ) {
+            item(key = "backdrop") {
+                // Edge to edge, fading into the page: the art is the first thing
+                // the page says, and a framed thumbnail with a margin round it read
+                // as one card among the many below it.
+                Box(Modifier.sharedArt(title.key).fillMaxWidth().height(backdropHeight)) {
+                    RemoteArtwork(
+                        title.backdropUrl ?: title.posterUrl,
+                        title.displayName,
+                        Modifier.fillMaxSize(),
+                        fallback = title.thumbnailSource,
+                        labelled = false,
+                    )
+                    Box(
+                        Modifier.fillMaxSize().background(
+                            Brush.verticalGradient(
+                                0.45f to Color.Transparent,
+                                1f to MaterialTheme.colorScheme.background,
+                            ),
+                        ),
+                    )
+                    IconButton(
+                        onClick = onBack,
+                        modifier = Modifier
+                            .statusBarsPadding()
+                            .padding(8.dp)
+                            .clip(CircleShape)
+                            .background(Color.Black.copy(alpha = 0.4f)),
+                    ) {
+                        Icon(Icons.AutoMirrored.Filled.ArrowBack, contentDescription = "Back to library", tint = Color.White)
+                    }
+                }
+            }
+            item(key = "heading") {
+                Column(Modifier.padding(horizontal = side + 16.dp)) {
+                    Text(title.displayName, style = MaterialTheme.typography.headlineMedium)
+                    // The other names it goes by: the share's when the shown one
+                    // is the provider's, and the original-language one.
+                    listOfNotNull(
+                        title.name.takeIf { it != title.displayName },
+                        title.originalName?.takeIf { it != title.displayName && it != title.canonicalName },
+                    ).joinToString("  ·  ").takeIf(String::isNotEmpty)?.let {
+                        Text(it, style = MaterialTheme.typography.bodyMedium, color = MaterialTheme.colorScheme.onSurfaceVariant)
+                    }
+                    Text(
+                        listOfNotNull(
+                            title.formatLabel,
+                            title.seasonLabel ?: (title.metadataYear ?: title.year)?.toString(),
+                            title.rating?.let { "★ %.1f".format(it) },
+                            "${title.watchedCount} of ${title.episodeCount} watched".takeIf { title.episodeCount > 1uL },
+                        ).joinToString("  ·  "),
+                        style = MaterialTheme.typography.bodySmall,
+                        color = MaterialTheme.colorScheme.onSurfaceVariant,
+                        modifier = Modifier.padding(top = 6.dp),
+                    )
+                    // Who made it, and whether more is coming — the desktop's
+                    // line of facts, on a line of its own so neither wraps.
+                    listOfNotNull(
+                        title.studios.takeIf { it.isNotEmpty() }?.take(2)?.joinToString(", "),
+                        title.directors.firstOrNull()?.let { "dir. $it" },
+                        airingNote(title),
+                    ).joinToString("  ·  ").takeIf(String::isNotEmpty)?.let {
+                        Text(
+                            it,
+                            style = MaterialTheme.typography.bodySmall,
+                            color = MaterialTheme.colorScheme.onSurfaceVariant,
+                            modifier = Modifier.padding(top = 2.dp),
+                        )
+                    }
+                    // The one thing the page is for, full width and naming what it
+                    // will play: "Resume" alone left the viewer guessing which
+                    // episode of forty it meant.
+                    AccentButton(
+                        onClick = { onPlay(playlist, nextUp) },
+                        enabled = playerReady && playlist.isNotEmpty(),
+                        modifier = Modifier.fillMaxWidth().padding(top = 16.dp),
+                    ) {
+                        Icon(Icons.Default.PlayArrow, contentDescription = null, modifier = Modifier.size(20.dp))
+                        Spacer(Modifier.width(8.dp))
+                        Text(
+                            when {
+                                !playerReady -> "Player loading…"
+                                upNext == null -> "Play"
+                                upNext.resumeAt != null -> "Resume ${upNext.label}"
+                                title.watchedCount > 0uL -> "Continue with ${upNext.label}"
+                                playlist.size == 1 -> "Play"
+                                else -> "Play ${upNext.label}"
+                            },
+                            maxLines = 1,
+                            overflow = TextOverflow.Ellipsis,
+                        )
+                    }
+                    // Everything else as labelled icons in one row: four actions of
+                    // three button styles used to wrap over three lines and bury
+                    // the episodes under them.
+                    Row(Modifier.fillMaxWidth().padding(top = 12.dp)) {
+                        // Only where it would do something different: an unstarted
+                        // show already starts at the beginning.
+                        if (upNext?.resumeAt != null || title.watchedCount > 0uL) {
+                            TitleAction(Icons.Default.Replay, "Start over", Modifier.weight(1f), enabled = playerReady) {
+                                onPlay(playlist, 0)
+                            }
+                        }
+                        TitleAction(Icons.Default.Download, "Download", Modifier.weight(1f)) {
+                            download(playlist, title.displayName)
+                        }
+                        TitleAction(Icons.Default.Edit, "Match", Modifier.weight(1f)) { showMatch = true }
+                        // The provider's own page for this title: where a viewer goes
+                        // to check that the thing the app matched is what they have.
+                        title.externalUrl?.let { url ->
+                            TitleAction(
+                                Icons.AutoMirrored.Filled.OpenInNew,
+                                title.metadataProvider?.displayName() ?: "Provider",
+                                Modifier.weight(1f),
+                            ) {
+                                runCatching {
+                                    context.startActivity(Intent(Intent.ACTION_VIEW, url.toUri()))
+                                }.onFailure(onPreferenceError)
+                            }
+                        }
+                    }
+                    title.overview?.let { overview ->
+                        // Three lines, then a tap for the rest: a synopsis with its
+                        // source notes ran to a screen and a half on a phone.
+                        Text(
+                            overview.trim(),
+                            maxLines = if (overviewOpen) Int.MAX_VALUE else 3,
+                            overflow = TextOverflow.Ellipsis,
+                            modifier = Modifier
+                                .padding(top = 12.dp)
+                                .clickable { overviewOpen = !overviewOpen },
+                        )
+                    }
+                    // Genres as chips, then the provider's tags quieter after
+                    // them: a tag is its community describing it, not what it
+                    // is filed as.
+                    if (title.genres.isNotEmpty() || title.tags.isNotEmpty()) {
+                        Text(
+                            (title.genres + title.tags.take(4)).joinToString("  ·  "),
+                            style = MaterialTheme.typography.labelMedium,
+                            color = MaterialTheme.colorScheme.onSurfaceVariant,
+                            modifier = Modifier.padding(top = 10.dp),
+                        )
+                    }
+                    // Said plainly, because it changes what a re-match will do: a
+                    // hand-picked match is not overwritten by an automatic pass.
+                    if (title.manualMatch) {
+                        Text(
+                            "Matched by hand",
+                            style = MaterialTheme.typography.labelMedium,
+                            color = MaterialTheme.colorScheme.onSurfaceVariant,
+                            modifier = Modifier.padding(top = 8.dp),
+                        )
+                    }
+                }
+            }
+            if (franchise.size > 1) {
+                item(key = "franchise") {
+                    Column(Modifier.padding(top = 12.dp)) {
+                        Text(
+                            "In this franchise",
+                            style = MaterialTheme.typography.titleMedium,
+                            modifier = Modifier.padding(horizontal = side + 16.dp),
+                        )
+                        LazyRow(
+                            horizontalArrangement = Arrangement.spacedBy(12.dp),
+                            contentPadding = PaddingValues(start = side + 16.dp, end = side + 16.dp, top = 10.dp),
+                        ) {
+                            items(franchise, key = { it.key }) { member ->
+                                FranchiseTile(member, here = member.key == title.key) { onOpenTitle(member) }
+                            }
+                        }
+                    }
+                }
+            }
+            item(key = "seasons") {
+                Row(
+                    Modifier.fillMaxWidth().padding(start = side + 16.dp, end = side + 4.dp, top = 12.dp),
+                    verticalAlignment = Alignment.CenterVertically,
+                ) {
+                    LazyRow(Modifier.weight(1f), horizontalArrangement = Arrangement.spacedBy(8.dp)) {
+                        // By position: two seasons can share a label, and a
+                        // repeated key is a crash in a lazy list.
+                        itemsIndexed(title.seasons, key = { index, _ -> index }) { index, entry ->
+                            FilterChip(
+                                selected = index == seasonIndex,
+                                onClick = { seasonIndex = index },
+                                label = { Text(entry.label) },
+                            )
+                        }
+                    }
+                    season?.let {
+                        // For someone joining the show partway, who would
+                        // otherwise tick every earlier episode one by one.
+                        val seen = it.episodes.all(EpisodeRecord::watched)
+                        IconButton(onClick = { onMarkEpisodes(it.episodes, !seen, "${title.displayName} ${it.label}") }) {
+                            Icon(
+                                if (seen) Icons.Default.RemoveDone else Icons.Default.DoneAll,
+                                contentDescription = "Mark ${it.label} ${if (seen) "unwatched" else "watched"}",
+                            )
+                        }
+                        IconButton(onClick = { download(it.episodes, "${title.displayName} ${it.label}") }) {
+                            Icon(Icons.Default.Download, contentDescription = "Download ${it.label}")
+                        }
+                    }
+                }
+            }
+            season?.let { shown ->
+                itemsIndexed(shown.episodes, key = { _, it -> it.linkId }) { position, episode ->
+                    Box(Modifier.padding(horizontal = side)) {
+                        EpisodeRow(
+                            episode = episode,
+                            numbering = episode.numbering(shown.number, position),
+                            position = position,
+                            download = downloads.firstOrNull {
+                                it.shareId == episode.shareId && it.linkId == episode.linkId
+                            },
+                            playerReady = playerReady,
+                            onPlay = { onPlay(playlist, playlist.indexOfFirst { it.linkId == episode.linkId }) },
+                            onDownload = { DownloadCoordinator.enqueue(context, episode) },
+                            onPause = { DownloadCoordinator.pause(context, it) },
+                            onResume = { DownloadCoordinator.resume(context, it) },
+                            onSetWatched = { onSetWatched(episode, it) },
+                            onWatchedUpTo = {
+                                val upTo = playlist.indexOfFirst { it.linkId == episode.linkId }
+                                onMarkEpisodes(
+                                    playlist.take(upTo + 1),
+                                    true,
+                                    "${title.displayName} up to ${episode.label}",
+                                )
+                            },
+                        )
+                    }
+                }
+            }
+        }
+    }
+    if (showMatch) {
+        ChangeMatchDialog(
+            title = title,
+            onDismiss = { showMatch = false },
+            onChanged = { showMatch = false; onMetadataChanged() },
+            onError = onPreferenceError,
+        )
+    }
+}
+
+/**
+ * One part of the franchise: its cover, what it is and when. This title's own
+ * is marked rather than left out, so the row says where it sits in the story.
+ */
+@Composable
+private fun FranchiseTile(title: TitleRecord, here: Boolean, onClick: () -> Unit) {
+    Column(
+        Modifier
+            .width(96.dp)
+            .clip(MaterialTheme.shapes.medium)
+            .clickable(enabled = !here, onClick = onClick),
+    ) {
+        RemoteArtwork(
+            title.posterUrl ?: title.backdropUrl,
+            title.displayName,
+            Modifier
+                .fillMaxWidth()
+                .aspectRatio(2f / 3f)
+                .clip(MaterialTheme.shapes.medium)
+                .then(
+                    if (here) {
+                        Modifier.border(2.dp, MaterialTheme.colorScheme.primary, MaterialTheme.shapes.medium)
+                    } else {
+                        Modifier
+                    },
+                ),
+            fallback = title.thumbnailSource,
+        )
+        Text(
+            title.displayName,
+            style = MaterialTheme.typography.labelMedium,
+            fontWeight = if (here) FontWeight.SemiBold else null,
+            maxLines = 2,
+            overflow = TextOverflow.Ellipsis,
+            modifier = Modifier.padding(top = 6.dp),
+        )
+        Text(
+            listOfNotNull(
+                title.formatLabel ?: if (title.kind == TitleType.FILM) "Film" else "Series",
+                (title.metadataYear ?: title.year)?.toString(),
+            ).joinToString(" · "),
+            style = MaterialTheme.typography.labelSmall,
+            color = MaterialTheme.colorScheme.onSurfaceVariant,
+            maxLines = 1,
+        )
+    }
+}
+
+/**
+ * "Episode 7 on Sat 11 Oct" while one is due, "Airing" while it is airing with
+ * no date yet, else nothing.
+ */
+private fun airingNote(title: TitleRecord): String? {
+    val at = title.nextAiringAt
+    val episode = title.nextEpisode
+    if (at != null && episode != null) {
+        val day = java.time.Instant.ofEpochSecond(at).atZone(java.time.ZoneId.systemDefault())
+        return "episode $episode on " + day.format(java.time.format.DateTimeFormatter.ofPattern("EEE d MMM"))
+    }
+    return if (title.airing) "airing" else null
+}
+
+/** How wide the page's text and controls run on a window wider than a phone. */
+private val READABLE_WIDTH = 720.dp
+
+/** One of the title's secondary actions: an icon with its name under it. */
+@Composable
+private fun TitleAction(
+    icon: ImageVector,
+    label: String,
+    modifier: Modifier = Modifier,
+    enabled: Boolean = true,
+    onClick: () -> Unit,
+) {
+    Column(
+        modifier
+            .clip(MaterialTheme.shapes.medium)
+            .clickable(enabled = enabled, onClick = onClick)
+            .padding(vertical = 8.dp),
+        horizontalAlignment = Alignment.CenterHorizontally,
+    ) {
+        Icon(icon, contentDescription = null)
+        Text(
+            label,
+            style = MaterialTheme.typography.labelMedium,
+            maxLines = 1,
+            overflow = TextOverflow.Ellipsis,
+            modifier = Modifier.padding(top = 4.dp),
+        )
+    }
+}
+
+/**
+ * `S03E38`, `E38`, or the row's place in the season.
+ *
+ * Mirrors `Episode::numbering` in `pstr-core`, plus the desktop client's
+ * fallback to the season folder's number. The last case is deliberately *not*
+ * printed as an episode number — nothing in the name numbered this file, and
+ * `#4` says "fourth in the list" where `E04` would be a claim about the show.
+ * Some ordinal is required regardless: a season of rows that all read the same
+ * is a season the viewer cannot navigate at all.
+ */
+private fun EpisodeRecord.numbering(fallbackSeason: UInt?, position: Int): String {
+    val season = this.season ?: fallbackSeason
+    val number = this.number
+    return when {
+        season != null && number != null -> "S%02dE%02d".format(season.toInt(), number.toInt())
+        number != null -> "E%02d".format(number.toInt())
+        else -> "#${position + 1}"
+    }
+}
+
+/**
+ * One episode: play it, see where it was left, and drive its download.
+ *
+ * The row *is* the play button — the still, the number and the name are one
+ * target, which is what lets the trailing controls be two icons in a fixed
+ * column rather than a second row of buttons under every episode.
+ */
+@Composable
+private fun EpisodeRow(
+    episode: EpisodeRecord,
+    numbering: String,
+    position: Int,
+    download: RetainedDownload?,
+    playerReady: Boolean,
+    onPlay: () -> Unit,
+    onDownload: () -> Unit,
+    onPause: (RetainedDownload) -> Unit,
+    onResume: (RetainedDownload) -> Unit,
+    onSetWatched: (Boolean) -> Unit,
+    onWatchedUpTo: () -> Unit = {},
+) {
+    // A long press, for someone joining a show partway: everything before
+    // this one ticked at once rather than one by one.
+    var menu by remember { mutableStateOf(false) }
+    val running = download?.status == RetainedDownload.STATUS_RUNNING ||
+        download?.status == RetainedDownload.STATUS_QUEUED
+    val heading = episode.heading(position)
+    Column(
+        Modifier
+            .fillMaxWidth()
+            .combinedClickable(
+                enabled = playerReady,
+                onClick = onPlay,
+                onLongClick = { menu = true },
+                onLongClickLabel = "More for this episode",
+            )
+            .padding(horizontal = 16.dp, vertical = 6.dp),
+    ) {
+        DropdownMenu(expanded = menu, onDismissRequest = { menu = false }) {
+            DropdownMenuItem(
+                text = { Text("Mark watched up to here") },
+                leadingIcon = { Icon(Icons.Default.DoneAll, contentDescription = null) },
+                onClick = {
+                    menu = false
+                    onWatchedUpTo()
+                },
+            )
+        }
+        Row(verticalAlignment = Alignment.CenterVertically) {
+            // With metadata off the provider has no still, and Proton's own
+            // thumbnail is a frame of this very episode. Where it was left sits
+            // on the still's lower edge, the way every streaming app shows it.
+            Box(
+                Modifier
+                    .width(128.dp)
+                    .aspectRatio(16f / 9f)
+                    .clip(MaterialTheme.shapes.small),
+                contentAlignment = Alignment.Center,
+            ) {
+                RemoteArtwork(
+                    episode.stillUrl,
+                    heading,
+                    Modifier.fillMaxSize(),
+                    fallback = episode.thumbnailSource,
+                    labelled = false,
+                )
+                episode.progress?.takeIf { !episode.watched }?.let { progress ->
+                    AccentProgress(
+                        progress = { progress.toFloat().coerceIn(0f, 1f) },
+                        modifier = Modifier.fillMaxWidth().align(Alignment.BottomCenter),
+                    )
+                }
+            }
+            Column(Modifier.weight(1f).padding(horizontal = 12.dp)) {
+                Text(
+                    heading,
+                    style = MaterialTheme.typography.titleSmall,
+                    // Seen episodes stay legible but stop competing with the
+                    // one the viewer has not watched yet.
+                    color = if (episode.watched) {
+                        MaterialTheme.colorScheme.onSurfaceVariant
+                    } else {
+                        MaterialTheme.colorScheme.onSurface
+                    },
+                    maxLines = 2,
+                    overflow = TextOverflow.Ellipsis,
+                )
+                Text(
+                    listOfNotNull(
+                        numbering,
+                        episode.size?.let(::formatBytes),
+                        episode.airDate,
+                    ).joinToString(" · "),
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                    maxLines = 1,
+                    overflow = TextOverflow.Ellipsis,
+                    modifier = Modifier.padding(top = 2.dp),
+                )
+            }
+            // Watched is a judgement the viewer is allowed to overrule: a
+            // half-watched episode they are done with, or one the 90 % rule
+            // marked seen because they sat through the credits.
+            IconButton(onClick = { onSetWatched(!episode.watched) }) {
+                Icon(
+                    if (episode.watched) Icons.Default.CheckCircle else Icons.Outlined.CheckCircle,
+                    contentDescription = if (episode.watched) "Mark unwatched" else "Mark watched",
+                    tint = if (episode.watched) {
+                        MaterialTheme.colorScheme.primary
+                    } else {
+                        MaterialTheme.colorScheme.outline
+                    },
+                )
+            }
+            // One slot, always the same width, whatever state the download
+            // is in — including "there is nothing to say", where an empty
+            // box keeps the rows above and below it aligned.
+            Box(Modifier.size(48.dp), contentAlignment = Alignment.Center) {
+                when {
+                    episode.offline -> Icon(
+                        Icons.Default.DownloadDone,
+                        contentDescription = "Saved offline",
+                        tint = MaterialTheme.colorScheme.tertiary,
+                    )
+                    running -> IconButton(onClick = { onPause(download!!) }) {
+                        Icon(Icons.Default.Pause, contentDescription = "Pause download")
+                    }
+                    download != null -> IconButton(onClick = { onResume(download) }) {
+                        Icon(Icons.Default.Download, contentDescription = "Resume download")
+                    }
+                    else -> IconButton(onClick = onDownload) {
+                        Icon(Icons.Default.Download, contentDescription = "Download")
+                    }
+                }
+            }
+        }
+        episode.providerOverview?.let {
+            Text(
+                it,
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+                maxLines = 2,
+                overflow = TextOverflow.Ellipsis,
+                modifier = Modifier.padding(top = 6.dp),
+            )
+        }
+        download?.takeIf { it.total > 0L && !episode.offline }?.let { active ->
+            AccentProgress(
+                progress = { (active.downloaded.toFloat() / active.total).coerceIn(0f, 1f) },
+                modifier = Modifier.fillMaxWidth().padding(top = 8.dp),
+                fill = solid(MaterialTheme.colorScheme.tertiary),
+            )
+            Text(
+                downloadStatusLine(active, rememberQueueReason(active)),
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+        }
+    }
+}
+
+@Composable
+internal fun ChangeMatchDialog(
+    title: TitleRecord,
+    onDismiss: () -> Unit,
+    onChanged: () -> Unit,
+    onError: (Throwable) -> Unit,
+) {
+    var term by remember(title.key) { mutableStateOf(title.canonicalName ?: title.name) }
+    var searching by remember { mutableStateOf(false) }
+    // Choosing fetches the entry's episodes too, which is a few requests.
+    var choosing by remember { mutableStateOf(false) }
+    var options by remember { mutableStateOf<List<MatchRecord>>(emptyList()) }
+    var confirmForget by remember { mutableStateOf(false) }
+    val scope = rememberCoroutineScope()
+    if (confirmForget) {
+        // Asked, because a match chosen by hand is work the next look-up
+        // does not redo: it decides again on its own.
+        AlertDialog(
+            onDismissRequest = { confirmForget = false },
+            title = { Text("Forget this match?") },
+            text = {
+                Text(
+                    "Its poster, description and episode names go, and the next look-up " +
+                        "matches it again on its own. A match you chose by hand is lost.",
+                )
+            },
+            confirmButton = {
+                DangerButton(onClick = {
+                    confirmForget = false
+                    scope.launch {
+                        runCatching { withContext(Dispatchers.IO) { NativeRuntime.engine().forgetMatch(title.key) } }
+                            .onSuccess { onChanged() }.onFailure(onError)
+                    }
+                }) { Text("Forget") }
+            },
+            dismissButton = { TonalButton(onClick = { confirmForget = false }) { Text("Cancel") } },
+        )
+        return
+    }
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        title = { Text("Change match") },
+        text = {
+            Column {
+                Text("Search the configured metadata provider. Nothing is stored until you choose an entry.")
+                OutlinedTextField(term, { term = it }, Modifier.fillMaxWidth().padding(vertical = 8.dp), singleLine = true)
+                AccentButton(enabled = term.isNotBlank() && !searching, onClick = {
+                    searching = true
+                    scope.launch {
+                        runCatching {
+                            withContext(Dispatchers.IO) { NativeRuntime.engine().searchMatches(title.key, term) }
+                        }.onSuccess { options = it }.onFailure(onError)
+                        searching = false
+                    }
+                }) { Text(if (searching) "Searching…" else "Search") }
+                if (choosing) {
+                    Text(
+                        "Fetching its episodes…",
+                        style = MaterialTheme.typography.bodySmall,
+                        modifier = Modifier.padding(top = 8.dp),
+                    )
+                }
+                LazyColumn(Modifier.fillMaxWidth().heightIn(max = 300.dp)) {
+                    items(options, key = { "${it.provider}:${it.remoteId}" }) { option ->
+                        EdgedButton(
+                            onClick = {
+                                choosing = true
+                                scope.launch {
+                                    runCatching {
+                                        withContext(Dispatchers.IO) { NativeRuntime.engine().chooseMatch(title.key, option) }
+                                    }.onSuccess { onChanged() }.onFailure(onError)
+                                    choosing = false
+                                }
+                            },
+                            enabled = !choosing,
+                            modifier = Modifier.fillMaxWidth().padding(top = 6.dp),
+                        ) {
+                            Column(Modifier.fillMaxWidth()) {
+                                Text(option.name, fontWeight = FontWeight.SemiBold)
+                                Text(listOfNotNull(option.year?.toString(), option.originalName).joinToString(" · "))
+                            }
+                        }
+                    }
+                }
+            }
+        },
+        confirmButton = {
+            QuietButton(onClick = { confirmForget = true }) { Text("Forget match") }
+        },
+        dismissButton = { TonalButton(onClick = onDismiss) { Text("Close") } },
+    )
+}

android/app/src/main/java/io/narl/protonstream/ui/theme/Accent.kt

@@ -0,0 +1,274 @@
+package io.narl.protonstream.ui.theme
+
+import androidx.compose.foundation.Canvas
+import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.RowScope
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.material3.Button
+import androidx.compose.material3.ButtonDefaults
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.FilledTonalButton
+import androidx.compose.material3.LocalMinimumInteractiveComponentSize
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.NavigationBarItemDefaults
+import androidx.compose.material3.NavigationDrawerItemDefaults
+import androidx.compose.material3.NavigationRailItemDefaults
+import androidx.compose.material3.OutlinedButton
+import androidx.compose.material3.adaptive.navigationsuite.NavigationSuiteDefaults
+import androidx.compose.material3.adaptive.navigationsuite.NavigationSuiteItemColors
+import androidx.compose.material3.SliderState
+import androidx.compose.material3.TextButton
+import androidx.compose.material3.minimumInteractiveComponentSize
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.geometry.CornerRadius
+import androidx.compose.ui.geometry.Size
+import androidx.compose.ui.graphics.Brush
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.SolidColor
+import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.unit.dp
+
+/**
+ * The accent, as a gradient when there is one to draw.
+ *
+ * The desktop paints the accent as a two-hue ramp on everything that is a
+ * control — the seek bar, the primary buttons, the tile progress bar — and the
+ * viewer's "paint the accent as a gradient" toggle is what turns it off. That
+ * toggle was already stored, already offered on this screen, and drawn nowhere
+ * on Android, so the same stored setting meant two different things depending
+ * on which client read it.
+ *
+ * Nothing here reads the toggle. It does not need to: when gradients are off,
+ * `Palette::resolve` sets `accent_alt` equal to `accent`, so the ramp collapses
+ * to a flat fill on its own. `primary` and `secondary` are those two colours —
+ * see [schemeOf] — which is why this asks Material for them rather than
+ * reaching past it for the palette.
+ */
+@Composable
+internal fun accentBrush(): Brush {
+    val scheme = MaterialTheme.colorScheme
+    return remember(scheme.primary, scheme.secondary) {
+        Brush.horizontalGradient(listOf(scheme.primary, scheme.secondary))
+    }
+}
+
+/**
+ * The primary button: the accent ramp, at the shared corner radius.
+ *
+ * Material's filled button has its own shape token (`CornerFull`) that does not
+ * read `MaterialTheme.shapes`, so the radius has to be handed to it — which is
+ * the whole reason the plain buttons below exist as well. They add nothing but
+ * that.
+ */
+@Composable
+internal fun AccentButton(
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier,
+    enabled: Boolean = true,
+    content: @Composable RowScope.() -> Unit,
+) {
+    val shape = MaterialTheme.shapes.small
+    // The button pads itself out to the 48dp minimum touch target, and a
+    // background on its modifier fills that whole target — 8dp taller than
+    // the 40dp container every other button draws. So the padding is taken
+    // here, outside the ramp, and the button inside is told not to add its
+    // own. The box hands its size down, so a `fillMaxWidth` still reaches it.
+    Box(
+        modifier.minimumInteractiveComponentSize(),
+        contentAlignment = Alignment.Center,
+        propagateMinConstraints = true,
+    ) {
+        CompositionLocalProvider(LocalMinimumInteractiveComponentSize provides Dp.Unspecified) {
+            Button(
+                onClick = onClick,
+                // Only while it is live: a disabled button keeps Material's flat
+                // disabled container, because a greyed control that still wears the
+                // one strong colour in the window reads as pressable.
+                modifier = if (enabled) Modifier.background(accentBrush(), shape) else Modifier,
+                enabled = enabled,
+                shape = shape,
+                colors = ButtonDefaults.buttonColors(containerColor = Color.Transparent),
+                content = content,
+            )
+        }
+    }
+}
+
+@Composable
+internal fun TonalButton(
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier,
+    enabled: Boolean = true,
+    content: @Composable RowScope.() -> Unit,
+) = FilledTonalButton(
+    onClick = onClick,
+    modifier = modifier,
+    enabled = enabled,
+    shape = MaterialTheme.shapes.small,
+    content = content,
+)
+
+@Composable
+internal fun EdgedButton(
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier,
+    enabled: Boolean = true,
+    content: @Composable RowScope.() -> Unit,
+) = OutlinedButton(
+    onClick = onClick,
+    modifier = modifier,
+    enabled = enabled,
+    shape = MaterialTheme.shapes.small,
+    content = content,
+)
+
+@Composable
+internal fun QuietButton(
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier,
+    enabled: Boolean = true,
+    content: @Composable RowScope.() -> Unit,
+) = TextButton(
+    onClick = onClick,
+    modifier = modifier,
+    enabled = enabled,
+    shape = MaterialTheme.shapes.small,
+    content = content,
+)
+
+/**
+ * The yes of a confirmation that deletes or forgets something.
+ *
+ * Not [AccentButton]: the filled accent is this app's "go on", and a dialog
+ * whose most inviting button is the one that loses something reads as the
+ * safe choice. Error-toned text instead, as Material's own guidance has it.
+ */
+@Composable
+internal fun DangerButton(
+    onClick: () -> Unit,
+    modifier: Modifier = Modifier,
+    enabled: Boolean = true,
+    content: @Composable RowScope.() -> Unit,
+) = TextButton(
+    onClick = onClick,
+    modifier = modifier,
+    enabled = enabled,
+    shape = MaterialTheme.shapes.small,
+    colors = ButtonDefaults.textButtonColors(contentColor = MaterialTheme.colorScheme.error),
+    content = content,
+)
+
+/**
+ * How far along something is, drawn in the accent.
+ *
+ * Hand-drawn rather than `LinearProgressIndicator` because that one takes a
+ * `Color` and not a `Brush`, and because Material 1.4 draws a gap and a stop
+ * indicator either side of the bar — detail at a size where the desktop draws a
+ * plain bar. [fill] is a parameter for the one bar that is deliberately not the
+ * accent: a download in flight sits directly under the watch-progress bar of
+ * the same row, and two ramps in the same colour stacked two pixels apart say
+ * nothing.
+ */
+@Composable
+internal fun AccentProgress(
+    progress: () -> Float,
+    modifier: Modifier = Modifier,
+    fill: Brush? = null,
+) {
+    val brush = fill ?: accentBrush()
+    val track = MaterialTheme.colorScheme.surfaceContainerHighest
+    Canvas(modifier.fillMaxWidth().height(PROGRESS_HEIGHT.dp)) {
+        val radius = CornerRadius(size.height / 2)
+        drawRoundRect(color = track, cornerRadius = radius)
+        val done = size.width * progress().coerceIn(0f, 1f)
+        // Below one bar's width there is nothing to round, and a rounded rect
+        // narrower than its own corners draws as a wrong-looking pill.
+        if (done >= size.height) {
+            drawRoundRect(brush = brush, size = Size(done, size.height), cornerRadius = radius)
+        }
+    }
+}
+
+/**
+ * The seek bar's track, in the accent ramp.
+ *
+ * Passed to `Slider`'s `track` slot, so the thumb, the gestures and the
+ * accessibility semantics stay Material's — this replaces the two rectangles it
+ * would have drawn and nothing else.
+ *
+ * The spent side is the accent and the rest is white at a third: the seek bar
+ * is the one accent surface that sits over arbitrary film footage, where a
+ * palette colour for the *unplayed* remainder would be a coloured line over a
+ * picture rather than the absence of one.
+ */
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+internal fun AccentTrack(state: SliderState, modifier: Modifier = Modifier, buffered: Float = 0f) {
+    val brush = accentBrush()
+    Canvas(modifier.fillMaxWidth().height(TRACK_HEIGHT.dp)) {
+        val radius = CornerRadius(size.height / 2)
+        drawRoundRect(color = Color.White.copy(alpha = 0.30f), cornerRadius = radius)
+        // What is already read ahead, lighter than the rest and under the
+        // played part: a jump that lands in it costs no fetch.
+        val ahead = size.width * buffered.coerceIn(0f, 1f)
+        if (ahead >= size.height) {
+            drawRoundRect(
+                color = Color.White.copy(alpha = 0.55f),
+                size = Size(ahead, size.height),
+                cornerRadius = radius,
+            )
+        }
+        val done = size.width * state.coercedValueAsFraction
+        if (done >= size.height) {
+            drawRoundRect(brush = brush, size = Size(done, size.height), cornerRadius = radius)
+        }
+    }
+}
+
+/**
+ * The navigation pill, in the accent.
+ *
+ * Solid rather than a ramp, and this is the one place the two clients cannot
+ * agree exactly: `NavigationSuiteScaffold` takes the indicator as a `Color`,
+ * with no slot to draw into, so a gradient here would mean reimplementing the
+ * bar. The accent itself is still the right answer — the desktop's rule is that
+ * the accent marks the thing you are on — and it is nearer to that than
+ * `secondaryContainer`, which is the accent taken most of the way back to the
+ * page.
+ */
+@Composable
+internal fun accentNavigationColors(): NavigationSuiteItemColors {
+    val scheme = MaterialTheme.colorScheme
+    return NavigationSuiteDefaults.itemColors(
+        navigationBarItemColors = NavigationBarItemDefaults.colors(
+            selectedIconColor = scheme.onPrimary,
+            selectedTextColor = scheme.onSurface,
+            indicatorColor = scheme.primary,
+        ),
+        navigationRailItemColors = NavigationRailItemDefaults.colors(
+            selectedIconColor = scheme.onPrimary,
+            selectedTextColor = scheme.onSurface,
+            indicatorColor = scheme.primary,
+        ),
+        navigationDrawerItemColors = NavigationDrawerItemDefaults.colors(
+            selectedContainerColor = scheme.primary,
+            selectedIconColor = scheme.onPrimary,
+            selectedTextColor = scheme.onPrimary,
+        ),
+    )
+}
+
+/** A solid fill, for the callers of [AccentProgress] that want one colour. */
+internal fun solid(color: Color): Brush = SolidColor(color)
+
+/** Thin enough to sit under a row without becoming part of it. */
+private const val PROGRESS_HEIGHT = 4f
+
+/** The seek bar is dragged with a finger, so it is the thicker of the two. */
+private const val TRACK_HEIGHT = 6f

android/app/src/main/java/io/narl/protonstream/ui/theme/Shape.kt

@@ -0,0 +1,36 @@
+package io.narl.protonstream.ui.theme
+
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material3.Shapes
+import androidx.compose.ui.unit.dp
+
+/**
+ * One corner radius, which is the desktop client's corner radius.
+ *
+ * `pstr-app` rounds every surface it paints to 8 — cards, buttons, the tab
+ * pill, the progress bars — and only a badge over artwork is tighter, at 4.
+ * Material's default ramp runs 4 / 8 / 12 / 16 / 28, so a stock Compose screen
+ * puts a 28dp bottom sheet next to a 12dp card next to a fully-round button,
+ * and none of those is the shape the other client draws.
+ *
+ * Flat rather than a ramp, therefore, with the two ends kept for the two cases
+ * where a single radius is wrong: `extraSmall` for something small enough that
+ * 8 would eat it, and `extraLarge` for a sheet whose corners meet the edge of
+ * the screen and need to read as a lifted sheet rather than a seam.
+ */
+internal val ProtonShapes = Shapes(
+    extraSmall = RoundedCornerShape(CORNER_TIGHT.dp),
+    small = RoundedCornerShape(CORNER.dp),
+    medium = RoundedCornerShape(CORNER.dp),
+    large = RoundedCornerShape(CORNER.dp),
+    extraLarge = RoundedCornerShape(CORNER_SHEET.dp),
+)
+
+/** The radius `pstr-app` draws everything at. */
+internal const val CORNER = 8f
+
+/** A badge over artwork — `theme::radius::BADGE` in pstr-app is the other place this number lives. */
+internal const val CORNER_TIGHT = 4f
+
+/** A bottom sheet, which has no desktop counterpart. */
+internal const val CORNER_SHEET = 16f

android/app/src/main/java/io/narl/protonstream/ui/theme/Theme.kt

@@ -1,24 +1,222 @@
 package io.narl.protonstream.ui.theme
 
+import androidx.compose.material3.ColorScheme
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.darkColorScheme
+import androidx.compose.material3.lightColorScheme
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
 import androidx.compose.ui.graphics.Color
+import io.narl.protonstream.native.NativeRuntime
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.withContext
+import uniffi.pstr_android.PaletteRecord
 
-private val ProtonColors = darkColorScheme(
+/**
-    primary = Color(0xFFCBA6F7),
+ * The palette in force, shared across every composition.
-    onPrimary = Color(0xFF1E1E2E),
+ *
-    secondary = Color(0xFFF5C2E7),
+ * The choice is stored by Rust and resolved by Rust — the same flavours, the
-    background = Color(0xFF1E1E2E),
+ * same accent pairings and the same contrast rule the desktop client uses — so
-    surface = Color(0xFF181825),
+ * what lives here is only the resolved answer and a way to replace it when the
-    surfaceVariant = Color(0xFF313244),
+ * viewer picks something else.
-    onBackground = Color(0xFFCDD6F4),
+ */
-    onSurface = Color(0xFFCDD6F4),
+object AppearanceState {
-    outline = Color(0xFF6C7086),
+    private val current = MutableStateFlow<PaletteRecord?>(null)
-    error = Color(0xFFF38BA8),
+    val palette: StateFlow<PaletteRecord?> = current.asStateFlow()
-)
+
+    /**
+     * The palette read before the first frame, from
+     * [io.narl.protonstream.native.NativeRuntime.storedPalette].
+     *
+     * Separate from [load] because it runs on the main thread during
+     * `onCreate`: it is the only read that is early enough to decide what the
+     * first composition is painted in, and it is cheap enough to be allowed
+     * there.
+     */
+    fun seed(palette: PaletteRecord) {
+        current.value = palette
+    }
+
+    /**
+     * Read the stored choice through the engine. Safe to call repeatedly; the
+     * last read wins.
+     *
+     * A no-op once [seed] has run — it resolves the same file through the same
+     * Rust, so the only thing a second read can do is build the engine earlier
+     * than the first screen needed it.
+     */
+    suspend fun load() {
+        if (current.value != null) return
+        runCatching { withContext(Dispatchers.IO) { NativeRuntime.engine().palette() } }
+            .onSuccess { current.value = it }
+    }
+
+    /** Read the stored choice again, after sync rewrote it. */
+    suspend fun reload() {
+        runCatching { withContext(Dispatchers.IO) { NativeRuntime.engine().palette() } }
+            .onSuccess { current.value = it }
+    }
+
+    /** Repaint immediately, before the write that stores the choice lands. */
+    fun apply(palette: PaletteRecord) {
+        current.value = palette
+    }
+}
 
 @Composable
 fun ProtonStreamTheme(content: @Composable () -> Unit) {
-    MaterialTheme(colorScheme = ProtonColors, content = content)
+    val palette by AppearanceState.palette.collectAsState()
+    // Before the first read, and if it fails, the palette this app shipped
+    // with — a theme file that cannot be read must never be a reason the
+    // library does not open.
+    LaunchedEffect(Unit) { AppearanceState.load() }
+    MaterialTheme(
+        colorScheme = schemeOf(palette ?: ProtonFallback),
+        // The other two thirds of what the clients share. Colour was already
+        // one resolved answer for both; type and shape were Material's defaults
+        // here and named constants there, which is most of why the two read as
+        // different apps even where the colours agreed.
+        typography = ProtonTypography,
+        shapes = ProtonShapes,
+        content = content,
+    )
 }
+
+/**
+ * One resolved palette as Material's roles — **all** of them.
+ *
+ * Every role Material names has to be answered here, because a role left out
+ * does not fall back to something neutral: it keeps the value
+ * `darkColorScheme()` / `lightColorScheme()` gave it, which is Material's own
+ * baseline purple-and-grey and belongs to no flavour this app ships.
+ *
+ * That is not hypothetical. `surfaceContainerHighest` is what `Card` fills with
+ * (`FilledCardTokens.ContainerColor`), and while it was unmapped every tile in
+ * the library grid, every episode row, every share and every download was drawn
+ * in baseline neutral on top of a flavoured page. `inverseSurface` is the
+ * snackbar — the app's only error channel — and `scrim` is the dim behind every
+ * dialog.
+ *
+ * Material names more roles than a palette has colours, so several are answered
+ * by the same one, and two (`elevated`, `dangerDim`) are derived in Rust so the
+ * blend behind them is the shared one. `SchemeRolesTest` asserts that nothing
+ * here is left at its baseline.
+ */
+internal fun schemeOf(palette: PaletteRecord): ColorScheme {
+    val base = if (palette.light) lightColorScheme() else darkColorScheme()
+    return base.copy(
+        primary = color(palette.accent),
+        onPrimary = color(palette.onAccent),
+        primaryContainer = color(palette.accentDim),
+        onPrimaryContainer = color(palette.text),
+        // Readable *on* `inverseSurface`, which is the ink colour: `accentDim`
+        // is the accent taken towards the page, so it inverts with the rest.
+        inversePrimary = color(palette.accentDim),
+        secondary = color(palette.accentAlt),
+        onSecondary = color(palette.onAccent),
+        // The accent taken back towards the page, not the card's hover shade.
+        // `secondaryContainer` is what fills every tonal button and the
+        // navigation bar's selected pill, and `cardHover` sits one step off
+        // `card` — which on a dark flavour made all of them dark grey shapes on
+        // a dark grey row, readable as text but not as controls.
+        secondaryContainer = color(palette.accentDim),
+        onSecondaryContainer = color(palette.text),
+        // The palette has two hues, not three. Tertiary takes the second one —
+        // the gradient partner — rather than inventing a third that no flavour
+        // chose.
+        tertiary = color(palette.accentAlt),
+        onTertiary = color(palette.onAccent),
+        tertiaryContainer = color(palette.accentDim),
+        onTertiaryContainer = color(palette.text),
+        background = color(palette.background),
+        onBackground = color(palette.text),
+        surface = color(palette.surface),
+        onSurface = color(palette.text),
+        surfaceVariant = color(palette.card),
+        onSurfaceVariant = color(palette.muted),
+        // No elevation tint. Material tints a raised surface with `primary`,
+        // and the desktop draws no such tint at all — its rule is that the
+        // accent is the only strong colour in the window and everything wearing
+        // it is something to click. A card that is faintly accent-coloured
+        // because it happens to be raised breaks that.
+        surfaceTint = Color.Transparent,
+        // Genuinely inverted, both ways round: on a dark flavour this is a pale
+        // snackbar with dark ink, on Latte a dark one with pale ink.
+        inverseSurface = color(palette.text),
+        inverseOnSurface = color(palette.background),
+        error = color(palette.danger),
+        onError = color(palette.background),
+        errorContainer = color(palette.dangerDim),
+        onErrorContainer = color(palette.text),
+        // Swapped from what was here before, to match what Material draws with
+        // each: `outline` is a border meant to be seen (an outlined button,
+        // a swatch that is not selected), `outlineVariant` is a divider meant
+        // to be barely there. `border` is the fainter of the two.
+        outline = color(palette.muted),
+        outlineVariant = color(palette.border),
+        // Black in both of Material's own schemes, and for the same reason: a
+        // scrim is not a colour, it is an absence of light.
+        scrim = Color.Black,
+        surfaceBright = color(palette.elevated),
+        surfaceDim = color(palette.background),
+        // The containment ladder, in the order the palette already runs: the
+        // deepest colour in the flavour at the bottom, `elevated` — one step
+        // past the card's hover shade — at the top.
+        surfaceContainerLowest = color(palette.sunken),
+        surfaceContainerLow = color(palette.surface),
+        surfaceContainer = color(palette.card),
+        surfaceContainerHigh = color(palette.cardHover),
+        surfaceContainerHighest = color(palette.elevated),
+        // The fixed roles are Material's "the same in light and dark", which a
+        // per-flavour palette has no equivalent of. They take the accent pair
+        // rather than a baseline hue, so a component that reaches for one still
+        // lands inside the flavour.
+        primaryFixed = color(palette.accentDim),
+        primaryFixedDim = color(palette.accent),
+        onPrimaryFixed = color(palette.text),
+        onPrimaryFixedVariant = color(palette.muted),
+        secondaryFixed = color(palette.accentDim),
+        secondaryFixedDim = color(palette.accentAlt),
+        onSecondaryFixed = color(palette.text),
+        onSecondaryFixedVariant = color(palette.muted),
+        tertiaryFixed = color(palette.accentDim),
+        tertiaryFixedDim = color(palette.accentAlt),
+        onTertiaryFixed = color(palette.text),
+        onTertiaryFixedVariant = color(palette.muted),
+    )
+}
+
+/** A packed `0xAARRGGBB` from the bridge, as Compose wants it. */
+private fun color(argb: UInt) = Color(argb.toInt())
+
+/**
+ * The shipped default, spelled out for the case where Rust cannot be asked.
+ *
+ * A `PaletteRecord` rather than a `ColorScheme`, so that it goes through
+ * [schemeOf] like any other palette and inherits every mapping above — a
+ * fallback that answered only ten roles would be the same bug in a smaller
+ * place. The values are `pstr_core::appearance::Palette::PROTON`.
+ */
+internal val ProtonFallback = PaletteRecord(
+    background = 0xFF0E0E12u,
+    surface = 0xFF17171Du,
+    sunken = 0xFF0A0A0Du,
+    card = 0xFF1E1E26u,
+    cardHover = 0xFF2A2A35u,
+    border = 0xFF262630u,
+    text = 0xFFEAEAF0u,
+    muted = 0xFF8E8E9Cu,
+    accent = 0xFF7D4DFFu,
+    accentAlt = 0xFF3F6FE0u,
+    accentDim = 0xFF5333ADu,
+    onAccent = 0xFFEAEAF0u,
+    danger = 0xFFE05561u,
+    elevated = 0xFF333340u,
+    dangerDim = 0xFF7F2F37u,
+    light = false,
+)

android/app/src/main/java/io/narl/protonstream/ui/theme/Type.kt

@@ -0,0 +1,95 @@
+package io.narl.protonstream.ui.theme
+
+import androidx.compose.material3.Typography
+import androidx.compose.ui.text.TextStyle
+import androidx.compose.ui.text.font.Font
+import androidx.compose.ui.text.font.FontFamily
+import androidx.compose.ui.text.font.FontWeight
+import io.narl.protonstream.R
+import androidx.compose.ui.unit.sp
+
+/**
+ * Inter, the desktop client's face, from the same two files.
+ *
+ * Only Regular and SemiBold ship, as on the desktop. A `Medium` role resolves
+ * to Regular by the usual weight matching rather than to a synthesised bold,
+ * which is how the desktop draws it too.
+ *
+ * Above [ProtonTypography] on purpose: top-level properties initialise in
+ * file order, and a ramp built first would capture this as null and fall back
+ * to the system face without a word.
+ */
+internal val Inter = FontFamily(
+    Font(R.font.inter_regular, FontWeight.Normal),
+    Font(R.font.inter_semibold, FontWeight.SemiBold),
+)
+
+/**
+ * The type ramp, which is the desktop client's type ramp.
+ *
+ * `pstr_app::theme::Role` names nine sizes and the desktop asks for a role
+ * rather than a number at every call site. Material names fifteen styles, so
+ * several of them land on the same rung — that is the point. The two clients
+ * were built to share one palette; sharing one scale is the other half of why
+ * they should read as one app.
+ *
+ * The rungs, largest first: 26 / 20 / 18 / 17 / 15 / 14 / 13 / 12 / 11.
+ *
+ * Where a role maps is decided by what actually draws with it here, not by
+ * Material's own sizes — Material's `displayLarge` is 57sp, which is a size for
+ * a phone's lock screen and not for anything in a library grid. `bodyLarge` is
+ * what an unstyled `Text` gets, so it takes the desktop's body rung and the two
+ * smaller body styles step down from there.
+ *
+ * [TypeRampTest] pins every one of these against the Rust ramp.
+ */
+internal val ProtonTypography = Typography(
+    displayLarge = role(DISPLAY, FontWeight.SemiBold),
+    displayMedium = role(DISPLAY, FontWeight.SemiBold),
+    displaySmall = role(TITLE, FontWeight.SemiBold),
+    // The name of the title you opened — the desktop's display line.
+    headlineLarge = role(DISPLAY, FontWeight.SemiBold),
+    headlineMedium = role(DISPLAY, FontWeight.SemiBold),
+    // A dialog's heading — `AlertDialog` titles draw with this one.
+    headlineSmall = role(HEADING, FontWeight.SemiBold),
+    // A page heading: "Offline downloads", "Settings".
+    titleLarge = role(TITLE, FontWeight.SemiBold),
+    // A run of content under a heading: "Continue watching", "Playback".
+    titleMedium = role(SECTION, FontWeight.Medium),
+    // A row that groups the rows under it — a season header.
+    titleSmall = role(SUBHEAD, FontWeight.Medium),
+    bodyLarge = role(BODY, FontWeight.Normal),
+    bodyMedium = role(LABEL, FontWeight.Normal),
+    // Context rather than content: counts, sizes, the note under a field.
+    bodySmall = role(CAPTION, FontWeight.Normal),
+    // The text on a button.
+    labelLarge = role(LABEL, FontWeight.Medium),
+    labelMedium = role(CAPTION, FontWeight.Medium),
+    // The smallest thing that stays legible.
+    labelSmall = role(MICRO, FontWeight.Medium),
+)
+
+internal const val DISPLAY = 26f
+internal const val TITLE = 20f
+internal const val HEADING = 18f
+internal const val SECTION = 17f
+internal const val SUBHEAD = 15f
+internal const val BODY = 14f
+internal const val LABEL = 13f
+internal const val CAPTION = 12f
+internal const val MICRO = 11f
+
+/**
+ * One rung as a `TextStyle`.
+ *
+ * Line height is derived rather than named per style: a ramp whose leading was
+ * chosen nine separate times is the same problem the sizes had. 1.35 is loose
+ * enough for the two-line title names in the grid and tight enough that a
+ * label on a control does not float.
+ */
+private fun role(size: Float, weight: FontWeight) = TextStyle(
+    fontSize = size.sp,
+    lineHeight = (size * 1.35f).sp,
+    fontWeight = weight,
+    fontFamily = Inter,
+)

android/app/src/main/res/drawable/ic_launcher_background.xml

@@ -0,0 +1,20 @@
+<!--
+  The launcher tile: packaging/io.narl.proton-stream.svg's face gradient, on
+  the full 108dp canvas because the launcher cuts its own shape out of it.
+-->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:aapt="http://schemas.android.com/aapt"
+    android:width="108dp" android:height="108dp"
+    android:viewportWidth="108" android:viewportHeight="108">
+    <path android:pathData="M0,0h108v108h-108z">
+        <aapt:attr name="android:fillColor">
+            <gradient android:type="linear"
+                android:startX="0" android:startY="0"
+                android:endX="108" android:endY="108">
+                <item android:offset="0" android:color="#FFA48BFF" />
+                <item android:offset="0.55" android:color="#FF7552FF" />
+                <item android:offset="1" android:color="#FF5B36F2" />
+            </gradient>
+        </aapt:attr>
+    </path>
+</vector>

android/app/src/main/res/drawable/ic_launcher_foreground.xml

@@ -1,6 +1,34 @@
+<!--
+  The play mark from packaging/io.narl.proton-stream.svg, cut into the blocks a
+  revision is fetched in. The paths are in the SVG's 128-unit space; the group
+  maps its 104-unit tile onto the 72dp a launcher shows of a 108dp layer.
+  It centres x=70, between the glyph's centroid (66) and its box (73): the
+  SVG's own centre, 64, leaves it sitting visibly right in a round mask.
+-->
 <vector xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:aapt="http://schemas.android.com/aapt"
     android:width="108dp" android:height="108dp"
     android:viewportWidth="108" android:viewportHeight="108">
-    <path android:fillColor="#CBA6F7" android:pathData="M24,22h60v64h-60z" />
+    <group
-    <path android:fillColor="#1E1E2E" android:pathData="M45,39l26,15 -26,15z" />
+        android:pivotX="70" android:pivotY="62"
+        android:scaleX="0.6923" android:scaleY="0.6923"
+        android:translateX="-16" android:translateY="-8">
+        <group android:translateY="3">
+            <clip-path android:pathData="M0,0h63v128h-63zM68.5,0h10v128h-10zM84,0h44v128h-44z" />
+            <path android:fillColor="#4D2E1596" android:pathData="M50,41.5v41a6,6 0,0 0,9.1 5.1l34.2,-20.5a6,6 0,0 0,0 -10.3L59.1,36.4A6,6 0,0 0,50 41.5z" />
+        </group>
+        <group>
+            <clip-path android:pathData="M0,0h63v128h-63zM68.5,0h10v128h-10zM84,0h44v128h-44z" />
+            <path android:pathData="M50,41.5v41a6,6 0,0 0,9.1 5.1l34.2,-20.5a6,6 0,0 0,0 -10.3L59.1,36.4A6,6 0,0 0,50 41.5z">
+                <aapt:attr name="android:fillColor">
+                    <gradient android:type="linear"
+                        android:startX="0" android:startY="36"
+                        android:endX="0" android:endY="88">
+                        <item android:offset="0" android:color="#FFFFFFFF" />
+                        <item android:offset="1" android:color="#FFECE6FF" />
+                    </gradient>
+                </aapt:attr>
+            </path>
+        </group>
+    </group>
 </vector>

android/app/src/main/res/drawable/ic_launcher_monochrome.xml

@@ -0,0 +1,12 @@
+<!-- The foreground's glyph as one flat shape, for themed launcher icons. -->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="108dp" android:height="108dp"
+    android:viewportWidth="108" android:viewportHeight="108">
+    <group
+        android:pivotX="70" android:pivotY="62"
+        android:scaleX="0.6923" android:scaleY="0.6923"
+        android:translateX="-16" android:translateY="-8">
+        <clip-path android:pathData="M0,0h63v128h-63zM68.5,0h10v128h-10zM84,0h44v128h-44z" />
+        <path android:fillColor="#FFFFFFFF" android:pathData="M50,41.5v41a6,6 0,0 0,9.1 5.1l34.2,-20.5a6,6 0,0 0,0 -10.3L59.1,36.4A6,6 0,0 0,50 41.5z" />
+    </group>
+</vector>

android/app/src/main/res/drawable/ic_notification_stream.xml

@@ -0,0 +1,16 @@
+<!--
+  The status-bar glyph. Android tints small icons to a single colour and drops
+  everything that is not opaque, so this is the launcher's sliced play mark as
+  one white silhouette, scaled from the SVG's 128-unit space onto 24dp.
+-->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp" android:height="24dp"
+    android:viewportWidth="24" android:viewportHeight="24">
+    <group
+        android:pivotX="70" android:pivotY="62"
+        android:scaleX="0.37" android:scaleY="0.37"
+        android:translateX="-58" android:translateY="-50">
+        <clip-path android:pathData="M0,0h63v128h-63zM68.5,0h10v128h-10zM84,0h44v128h-44z" />
+        <path android:fillColor="#FFFFFFFF" android:pathData="M50,41.5v41a6,6 0,0 0,9.1 5.1l34.2,-20.5a6,6 0,0 0,0 -10.3L59.1,36.4A6,6 0,0 0,50 41.5z" />
+    </group>
+</vector>

android/app/src/main/res/mipmap-anydpi/ic_launcher.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@drawable/ic_launcher_background" />
+    <foreground android:drawable="@drawable/ic_launcher_foreground" />
+    <monochrome android:drawable="@drawable/ic_launcher_monochrome" />
+</adaptive-icon>

android/app/src/main/res/values/colors.xml

@@ -0,0 +1,9 @@
+<resources>
+    <!--
+      `pstr_core::appearance::Palette::PROTON.background` — the shipped default,
+      and the only colour in this file. It is what the window is painted before
+      the stored palette has been read; from then on
+      MainActivity.dressWindow overrides it with the flavour in force.
+    -->
+    <color name="window_background">#0E0E12</color>
+</resources>

android/app/src/main/res/values/strings.xml

@@ -1,3 +1,9 @@
 <resources>
-    <string name="app_name">proton-stream</string>
+    <!-- Settings, recents, notifications and the share sheet: room for the full name. -->
+    <string name="app_name">Proton Stream</string>
+    <!--
+      Under the launcher icon, where about ten characters fit before the
+      launcher cuts the label off; "proton-stream" showed as "proton-st…".
+    -->
+    <string name="launcher_name">Stream</string>
 </resources>

android/app/src/main/res/values/themes.xml

@@ -1,8 +1,23 @@
 <resources>
+    <!--
+      The window before Compose owns it.
+
+      Everything about the *look* is decided by the stored palette and applied
+      in MainActivity.dressWindow: the background colour here is only the one
+      the shipped default resolves to, so that a first-ever launch — before
+      there is a theme file to read — starts on the right colour rather than on
+      the platform's white. The bar polarity is likewise set from the palette;
+      what is left here is the dark reading, which is right for four of the five
+      flavours and is corrected in the same frame for the fifth.
+
+      A hex literal from one specific flavour used to live here, and it was the
+      reason every cold start flashed Catppuccin Mocha's base regardless of what
+      the viewer had chosen.
+    -->
     <style name="Theme.ProtonStream" parent="android:style/Theme.Material.NoActionBar">
         <item name="android:fontFamily">sans</item>
         <item name="android:windowLightStatusBar">false</item>
         <item name="android:windowLightNavigationBar">false</item>
-        <item name="android:windowBackground">#1E1E2E</item>
+        <item name="android:windowBackground">@color/window_background</item>
     </style>
 </resources>

android/app/src/test/java/io/narl/protonstream/IncomingShareLinkTest.kt

@@ -0,0 +1,37 @@
+package io.narl.protonstream
+
+import android.content.Intent
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
+import org.junit.Test
+
+class IncomingShareLinkTest {
+    private val link = "https://drive.proton.me/urls/ABC123#s3cr3t"
+
+    @Test
+    fun `a viewed share link is taken whole, fragment included`() {
+        assertEquals(link, shareLinkFrom(Intent.ACTION_VIEW, link, null))
+    }
+
+    @Test
+    fun `a viewed url that is not an https share link is ignored`() {
+        assertNull(shareLinkFrom(Intent.ACTION_VIEW, "https://drive.proton.me/u/0/", null))
+        assertNull(shareLinkFrom(Intent.ACTION_VIEW, "http://drive.proton.me/urls/ABC123#s3cr3t", null))
+    }
+
+    @Test
+    fun `a shared message yields the link inside it`() {
+        assertEquals(link, shareLinkFrom(Intent.ACTION_SEND, null, "Season two is up: $link enjoy"))
+        assertEquals(link, shareLinkFrom(Intent.ACTION_SEND, null, "(<$link>)"))
+    }
+
+    @Test
+    fun `a shared message without a link yields nothing`() {
+        assertNull(shareLinkFrom(Intent.ACTION_SEND, null, "no link here"))
+    }
+
+    @Test
+    fun `other actions are ignored`() {
+        assertNull(shareLinkFrom(Intent.ACTION_MAIN, link, link))
+    }
+}

android/app/src/test/java/io/narl/protonstream/download/DownloadStateStoreTest.kt

@@ -0,0 +1,155 @@
+package io.narl.protonstream.download
+
+import android.content.Context
+import androidx.test.core.app.ApplicationProvider
+import org.json.JSONObject
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNull
+import org.junit.Assert.assertTrue
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.robolectric.RobolectricTestRunner
+
+@RunWith(RobolectricTestRunner::class)
+class DownloadStateStoreTest {
+    private lateinit var context: Context
+    private lateinit var store: DownloadStateStore
+
+    @Before
+    fun setUp() {
+        context = ApplicationProvider.getApplicationContext()
+        context.getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE).edit().clear().commit()
+        store = DownloadStateStore(context)
+    }
+
+    private fun record(
+        shareId: String = "share-1",
+        linkId: String = "link-1",
+        label: String = "S01E01.mkv",
+        status: String = RetainedDownload.STATUS_RUNNING,
+        error: String? = null,
+    ) = RetainedDownload(
+        shareId = shareId,
+        volumeId = "volume-1",
+        linkId = linkId,
+        label = label,
+        downloaded = 4L * 1024 * 1024,
+        total = 761L * 1024 * 1024,
+        status = status,
+        error = error,
+    )
+
+    @Test
+    fun `a record survives a round trip unchanged`() {
+        val original = record()
+        store.put(original)
+        assertEquals(original, store.get("share-1", "link-1"))
+    }
+
+    @Test
+    fun `an absent record reads as null rather than a default`() {
+        assertNull(store.get("share-1", "link-1"))
+    }
+
+    @Test
+    fun `an error message round trips and a null one stays null`() {
+        store.put(record(error = "no space left on device"))
+        assertEquals("no space left on device", store.get("share-1", "link-1")?.error)
+
+        store.put(record(error = null))
+        assertNull(store.get("share-1", "link-1")?.error)
+    }
+
+    /**
+     * `encode` writes `error` through `JSONObject.put`, which *removes* the key
+     * when the value is null. `decode` then reads `optString`, which answers ""
+     * rather than null. The blank check is the only thing standing between a
+     * cleared error and a download that renders as permanently failed.
+     */
+    @Test
+    fun `a blank error is not read as a failure message`() {
+        writeRaw(
+            "share-1",
+            "link-1",
+            baseJson().put("error", ""),
+        )
+        assertNull(store.get("share-1", "link-1")?.error)
+    }
+
+    /** Rows written before `label` existed fall back to the link id. */
+    @Test
+    fun `a record with no label is captioned with its link id`() {
+        writeRaw("share-1", "link-1", baseJson().apply { remove("label") })
+        assertEquals("link-1", store.get("share-1", "link-1")?.label)
+    }
+
+    @Test
+    fun `a corrupt row is skipped rather than failing the whole list`() {
+        store.put(record(linkId = "link-1", label = "good.mkv"))
+        context.getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE)
+            .edit()
+            .putString("share-1\u001flink-broken", "{ not json")
+            .commit()
+
+        val records = store.records()
+        assertEquals(1, records.size)
+        assertEquals("good.mkv", records.first().label)
+    }
+
+    @Test
+    fun `records are ordered by label without regard to case`() {
+        store.put(record(linkId = "a", label = "beta.mkv"))
+        store.put(record(linkId = "b", label = "Alpha.mkv"))
+        assertEquals(listOf("Alpha.mkv", "beta.mkv"), store.records().map { it.label })
+    }
+
+    @Test
+    fun `removing one share leaves the others alone`() {
+        store.put(record(shareId = "share-1", linkId = "a"))
+        store.put(record(shareId = "share-2", linkId = "b"))
+
+        store.removeShare("share-1")
+
+        assertEquals(listOf("share-2"), store.records().map { it.shareId })
+    }
+
+    @Test
+    fun `clear forgets everything`() {
+        store.put(record(linkId = "a"))
+        store.put(record(linkId = "b"))
+        store.clear()
+        assertTrue(store.records().isEmpty())
+    }
+
+    /**
+     * The key is what `DownloadCoordinator` and `OfflineDownloadWorker` agree on
+     * across processes; two shares may legitimately hold the same link id.
+     */
+    @Test
+    fun `the key separates share from link so ids cannot run together`() {
+        store.put(record(shareId = "a", linkId = "b-c"))
+        store.put(record(shareId = "a-b", linkId = "c"))
+        assertEquals(2, store.records().size)
+    }
+
+    private fun baseJson() = JSONObject()
+        .put("share", "share-1")
+        .put("volume", "volume-1")
+        .put("link", "link-1")
+        .put("label", "S01E01.mkv")
+        .put("downloaded", 0)
+        .put("total", 0)
+        .put("status", RetainedDownload.STATUS_QUEUED)
+
+    private fun writeRaw(shareId: String, linkId: String, json: JSONObject) {
+        context.getSharedPreferences(PREFERENCES, Context.MODE_PRIVATE)
+            .edit()
+            .putString("$shareId\u001f$linkId", json.toString())
+            .commit()
+    }
+
+    private companion object {
+        const val PREFERENCES = "offline_download_state"
+    }
+}

android/app/src/test/java/io/narl/protonstream/download/TransferRateTest.kt

@@ -0,0 +1,37 @@
+package io.narl.protonstream.download
+
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+class TransferRateTest {
+    @Test
+    fun `the first sample has no rate to report`() {
+        assertEquals(0L, TransferRate().sample(4L * 1024 * 1024, 1_000))
+    }
+
+    @Test
+    fun `a steady transfer reports its rate`() {
+        val rate = TransferRate()
+        rate.sample(0, 0)
+        assertEquals(1_000_000L, rate.sample(1_000_000, 1_000))
+        assertEquals(1_000_000L, rate.sample(2_000_000, 2_000))
+    }
+
+    @Test
+    fun `one slow block moves the rate without halving it`() {
+        val rate = TransferRate()
+        rate.sample(0, 0)
+        rate.sample(1_000_000, 1_000)
+        val after = rate.sample(2_000_000, 3_000)
+        assertTrue(after in 600_000L..999_999L)
+    }
+
+    @Test
+    fun `a resumed download starting below the last sample starts over`() {
+        val rate = TransferRate()
+        rate.sample(0, 0)
+        rate.sample(1_000_000, 1_000)
+        assertEquals(1_000_000L, rate.sample(0, 2_000))
+    }
+}

android/app/src/test/java/io/narl/protonstream/ui/AccountUiTest.kt

@@ -0,0 +1,38 @@
+package io.narl.protonstream.ui
+
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+class AccountUiTest {
+    @Test
+    fun `the sync line says how long ago and what came in`() {
+        val minute = 60_000L
+        assertEquals("Library, settings and watch history sync through your Drive", syncLine(AccountUiState(), 0))
+        assertEquals("Synced just now", syncLine(AccountUiState(syncedAt = 0), 30_000))
+        assertEquals("Synced 5 min ago", syncLine(AccountUiState(syncedAt = 0), 5 * minute))
+        assertEquals(
+            "Synced 2 h ago · 3 from other devices",
+            syncLine(AccountUiState(syncedAt = 0, applied = 3), 120 * minute),
+        )
+    }
+
+    @Test
+    fun `a failed sync is said in place of when it last worked`() {
+        assertEquals(
+            "Did not sync: offline",
+            syncLine(AccountUiState(syncedAt = 0, syncError = "offline"), 0),
+        )
+    }
+
+    @Test
+    fun `the verification page may only navigate within Proton over https`() {
+        assertTrue(isProtonPage("https", "verify.proton.me"))
+        assertTrue(isProtonPage("https", "proton.me"))
+        assertFalse(isProtonPage("http", "verify.proton.me"))
+        assertFalse(isProtonPage("https", "proton.me.example.com"))
+        assertFalse(isProtonPage("https", "notproton.me"))
+        assertFalse(isProtonPage("https", null))
+    }
+}

android/app/src/test/java/io/narl/protonstream/ui/ArtworkTest.kt

@@ -0,0 +1,28 @@
+package io.narl.protonstream.ui
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+class ArtworkTest {
+    @Test
+    fun `initials skip the lower-case particles of a romanised name`() {
+        assertEquals("OK", initials("Oshi no Ko"))
+        assertEquals("AH", initials("Ano Hi Mita Hana no Namae o Bokutachi wa Mada Shiranai."))
+    }
+
+    @Test
+    fun `a one-word name has one initial`() {
+        assertEquals("A", initials("Akira"))
+    }
+
+    @Test
+    fun `a name with no capitals falls back to its first two words`() {
+        assertEquals("BW", initials("blue world order"))
+    }
+
+    @Test
+    fun `punctuation and separators are not words`() {
+        assertEquals("S2", initials("Steins;Gate - 2"))
+        assertEquals("", initials(" - "))
+    }
+}

android/app/src/test/java/io/narl/protonstream/ui/HistoryTest.kt

@@ -0,0 +1,59 @@
+package io.narl.protonstream.ui
+
+import java.time.LocalDate
+import java.util.Locale
+import org.junit.Assert.assertEquals
+import org.junit.Test
+import uniffi.pstr_android.EpisodeRecord
+import uniffi.pstr_android.SeasonRecord
+import uniffi.pstr_android.TitleRecord
+import uniffi.pstr_android.TitleType
+
+class HistoryTest {
+    private fun episode(link: String, watched: Boolean, progress: Double?, lastPlayed: Long) = EpisodeRecord(
+        shareId = "s", volumeId = "v", linkId = link, name = "$link.mkv", label = link, detail = "$link.mkv",
+        season = 1u, number = null, size = null, progress = progress, resumeAt = progress?.let { it * 1000 },
+        watched = watched, offline = false, providerName = null, providerOverview = null, stillUrl = null,
+        airDate = null, lastPlayed = lastPlayed,
+    )
+
+    private fun title(key: String, vararg episodes: EpisodeRecord) = TitleRecord(
+        key = key, name = key, year = null, kind = TitleType.SERIES, watchedCount = 0uL,
+        episodeCount = episodes.size.toULong(), canonicalName = null, originalName = null, overview = null,
+        metadataProvider = null, metadataId = null, metadataYear = null, metadataKind = null, posterUrl = null,
+        backdropUrl = null, rating = null, genres = emptyList(), providerEpisodeCount = null, externalUrl = null,
+        manualMatch = false, seasons = listOf(SeasonRecord(1u, "Season 1", episodes.toList())),
+        displayName = key, wideUrl = null, formatLabel = null, seasonLabel = null, studios = emptyList(),
+        directors = emptyList(), tags = emptyList(), airing = false, nextEpisode = null, nextAiringAt = null,
+        franchise = emptyList(),
+        continueIndex = null,
+    )
+
+    @Test
+    fun `history is every started or finished episode, newest first, across titles`() {
+        val titles = listOf(
+            title(
+                "a",
+                episode("a1", watched = true, progress = 1.0, lastPlayed = 30),
+                // Marked unwatched again: a row at zero, which is not a play.
+                episode("a2", watched = false, progress = 0.0, lastPlayed = 40),
+                episode("a3", watched = false, progress = null, lastPlayed = 0),
+            ),
+            title("b", episode("b1", watched = false, progress = 0.4, lastPlayed = 50)),
+        )
+        val played = history(titles)
+        assertEquals(listOf("b1", "a1"), played.map { it.episode.linkId })
+        assertEquals(0, played.last().index)
+    }
+
+    @Test
+    fun `days are headed relative to today, then by date`() {
+        val today = LocalDate.of(2026, 10, 3) // a Saturday
+        val english = Locale.ENGLISH
+        assertEquals("Today", dayHeading(today, today, english))
+        assertEquals("Yesterday", dayHeading(today.minusDays(1), today, english))
+        assertEquals("Monday", dayHeading(LocalDate.of(2026, 9, 28), today, english))
+        assertEquals("26 September", dayHeading(LocalDate.of(2026, 9, 26), today, english))
+        assertEquals("3 October 2025", dayHeading(LocalDate.of(2025, 10, 3), today, english))
+    }
+}

android/app/src/test/java/io/narl/protonstream/ui/LanguagePickerTest.kt

@@ -0,0 +1,31 @@
+package io.narl.protonstream.ui
+
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+class LanguagePickerTest {
+    @Test
+    fun `a stored tag reads as its language in either ISO form`() {
+        assertEquals("Japanese", languageLabel("jpn"))
+        assertEquals("Japanese", languageLabel("ja"))
+        assertEquals("German", languageLabel("deu"))
+        assertEquals("German", languageLabel("ger"))
+    }
+
+    @Test
+    fun `a region suffix and capitals do not hide the language`() {
+        assertEquals("Portuguese", languageLabel("PT-br"))
+    }
+
+    @Test
+    fun `a tag not on the list is shown as typed, and blank is no preference`() {
+        assertEquals("tgl", languageLabel("tgl"))
+        assertEquals("No preference", languageLabel(null))
+        assertEquals("No preference", languageLabel("  "))
+    }
+
+    @Test
+    fun `every listed language has a two-letter form`() {
+        LANGUAGES.forEach { (code, name) -> assertEquals(code, name, languageLabel(code)) }
+    }
+}

android/app/src/test/java/io/narl/protonstream/ui/ScreenshotTest.kt

@@ -0,0 +1,344 @@
+package io.narl.protonstream.ui
+
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.ui.test.junit4.createComposeRule
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.test.onRoot
+import androidx.compose.ui.unit.Density
+import androidx.test.core.app.ApplicationProvider
+import androidx.work.testing.WorkManagerTestInitHelper
+import com.github.takahirom.roborazzi.RobolectricDeviceQualifiers
+import com.github.takahirom.roborazzi.captureRoboImage
+import io.narl.protonstream.ui.theme.AppearanceState
+import io.narl.protonstream.ui.theme.ProtonFallback
+import io.narl.protonstream.ui.theme.ProtonStreamTheme
+import java.time.LocalDate
+import java.time.ZoneOffset
+import org.junit.Before
+import org.junit.Rule
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.robolectric.RobolectricTestRunner
+import org.robolectric.annotation.Config
+import org.robolectric.annotation.GraphicsMode
+import uniffi.pstr_android.ArrangementRecord
+import uniffi.pstr_android.EpisodeRecord
+import uniffi.pstr_android.MetadataProvider
+import uniffi.pstr_android.MetadataSettingsRecord
+import uniffi.pstr_android.OfflineRecord
+import uniffi.pstr_android.PaletteRecord
+import uniffi.pstr_android.SeasonRecord
+import uniffi.pstr_android.ShareRecord
+import uniffi.pstr_android.ShelfRecord
+import uniffi.pstr_android.StorageUsageRecord
+import uniffi.pstr_android.TileRecord
+import uniffi.pstr_android.TitleRecord
+import uniffi.pstr_android.TitleType
+
+/**
+ * Every screen, drawn from fixed records, against a committed image.
+ *
+ * The screens are about to be redesigned one by one, and a layout regression —
+ * a row that wraps, a button pushed off the edge — compiles and passes every
+ * other test. Here it is a changed PNG in review. No artwork is loaded: the
+ * bridge is not available on the host, so every tile shows its generated
+ * placeholder, which is also what a title without metadata looks like on a
+ * phone.
+ */
+@RunWith(RobolectricTestRunner::class)
+@GraphicsMode(GraphicsMode.Mode.NATIVE)
+@Config(qualifiers = RobolectricDeviceQualifiers.Pixel7)
+class ScreenshotTest {
+    @get:Rule val compose = createComposeRule()
+
+    @Before
+    fun setUp() {
+        WorkManagerTestInitHelper.initializeTestWorkManager(ApplicationProvider.getApplicationContext())
+        // The palette is process-wide and the sandbox outlives a test, so a
+        // light capture would otherwise repaint every one after it.
+        AppearanceState.apply(ProtonFallback)
+    }
+
+    private fun captureLight(name: String, content: @Composable () -> Unit) {
+        AppearanceState.apply(LATTE)
+        capture(name, content)
+    }
+
+    private fun capture(name: String, content: @Composable () -> Unit) {
+        compose.setContent {
+            ProtonStreamTheme {
+                CompositionLocalProvider(LocalArtworkLoading provides false) {
+                    Surface(color = MaterialTheme.colorScheme.background) { content() }
+                }
+            }
+        }
+        compose.onRoot().captureRoboImage("src/test/screenshots/$name.png")
+    }
+
+    @Test
+    fun `the library on a phone`() = capture("library-phone") {
+        LibraryScreen(MATCHED, {}, { _, _ -> }, {}, {}, { _, _ -> }, { _, _ -> }, PaddingValues())
+    }
+
+    @Test
+    fun `the library offering posters while they are off`() = capture("library-phone-offer") {
+        LibraryScreen(LIBRARY, {}, { _, _ -> }, {}, {}, { _, _ -> }, { _, _ -> }, PaddingValues())
+    }
+
+    @Test
+    @Config(qualifiers = RobolectricDeviceQualifiers.MediumTablet)
+    fun `the library on a tablet`() = capture("library-tablet") {
+        LibraryScreen(MATCHED, {}, { _, _ -> }, {}, {}, { _, _ -> }, { _, _ -> }, PaddingValues())
+    }
+
+    @Test
+    fun `the library in the light palette`() = captureLight("library-phone-light") {
+        LibraryScreen(MATCHED, {}, { _, _ -> }, {}, {}, { _, _ -> }, { _, _ -> }, PaddingValues())
+    }
+
+    @Test
+    fun `a title in the light palette`() = captureLight("title-phone-light") {
+        TitleScreen(SERIES, true, { _, _ -> }, {}, {}, {}, { _, _ -> }, PaddingValues())
+    }
+
+    @Test
+    @Config(qualifiers = RobolectricDeviceQualifiers.MediumTablet)
+    fun `a title on a tablet`() = capture("title-tablet") {
+        TitleScreen(SERIES, true, { _, _ -> }, {}, {}, {}, { _, _ -> }, PaddingValues())
+    }
+
+    @Test
+    @Config(qualifiers = RobolectricDeviceQualifiers.MediumTablet)
+    fun `the history page on a tablet`() = capture("history-tablet") {
+        HistoryScreen(LIBRARY, { _, _ -> }, {}, { _, _ -> }, PaddingValues(), ZoneOffset.UTC, LocalDate.of(2026, 9, 21))
+    }
+
+    @Test
+    fun `the library at a large font scale`() = capture("library-phone-large-font") {
+        // Robolectric has no font-scale qualifier; the density is what Compose
+        // reads it from, so the scale is set there.
+        val density = LocalDensity.current
+        CompositionLocalProvider(LocalDensity provides Density(density.density, fontScale = 1.5f)) {
+            LibraryScreen(MATCHED, {}, { _, _ -> }, {}, {}, { _, _ -> }, { _, _ -> }, PaddingValues())
+        }
+    }
+
+    @Test
+    fun `an empty library`() = capture("library-empty") {
+        LibraryScreen(AppUiState(loading = false), {}, { _, _ -> }, {}, {}, { _, _ -> }, { _, _ -> }, PaddingValues())
+    }
+
+    @Test
+    fun `the library while the catalog loads`() = capture("library-loading") {
+        LibraryScreen(AppUiState(), {}, { _, _ -> }, {}, {}, { _, _ -> }, { _, _ -> }, PaddingValues())
+    }
+
+    @Test
+    fun `a title with seasons`() = capture("title-phone") {
+        TitleScreen(SERIES, true, { _, _ -> }, {}, {}, {}, { _, _ -> }, PaddingValues(), franchise = listOf(SERIES, SEQUEL))
+    }
+
+    @Test
+    fun `the shares page`() = capture("shares-phone") {
+        SharesScreen(LIBRARY.shares, { _, _, _ -> null }, { _, _, _ -> }, {}, {}, null, {}, PaddingValues())
+    }
+
+    @Test
+    fun `the settings page`() = capture("settings-phone") {
+        SettingsScreen(LIBRARY, { _, _, _, _ -> null }, {}, {}, {}, PaddingValues(), version = "1.0.0")
+    }
+
+    @Test
+    fun `the playback settings`() = capture("settings-playback") {
+        SettingsScreen(LIBRARY, { _, _, _, _ -> null }, {}, {}, {}, PaddingValues(), SettingsPage.Playback)
+    }
+
+    @Test
+    fun `the storage settings`() = capture("settings-storage") {
+        SettingsScreen(LIBRARY, { _, _, _, _ -> null }, {}, {}, {}, PaddingValues(), SettingsPage.Storage)
+    }
+
+    @Test
+    fun `the history page`() = capture("history-phone") {
+        // Fixed day and zone: "Today" and "Yesterday" are relative, and an
+        // image that changes with the date is no baseline.
+        HistoryScreen(LIBRARY, { _, _ -> }, {}, { _, _ -> }, PaddingValues(), ZoneOffset.UTC, LocalDate.of(2026, 9, 21))
+    }
+
+    @Test
+    fun `the downloads page with a season saved`() = capture("downloads-phone") {
+        val saved = SERIES.seasons.first().episodes.take(2).map {
+            OfflineRecord(it.shareId, it.linkId, "revision", 1_300_000_000uL, it)
+        }
+        // One title: the fixtures reuse link ids across titles, so with the
+        // whole library the episodes would be filed under whichever came last.
+        DownloadsScreen(LIBRARY.copy(titles = listOf(SERIES), offline = saved), {}, {}, {}, {}, PaddingValues())
+    }
+
+    @Test
+    fun `the downloads page with nothing offline`() = capture("downloads-empty") {
+        DownloadsScreen(LIBRARY, {}, {}, {}, {}, PaddingValues())
+    }
+
+    private companion object {
+        /** Catppuccin Latte with the default accent, as `Palette::resolve` gives it. */
+        val LATTE = PaletteRecord(
+            background = 0xFFEFF1F5u,
+            surface = 0xFFE6E9EFu,
+            sunken = 0xFFDCE0E8u,
+            card = 0xFFCCD0DAu,
+            cardHover = 0xFFBCC0CCu,
+            border = 0xFFBCC0CCu,
+            text = 0xFF4C4F69u,
+            muted = 0xFF6C6F85u,
+            accent = 0xFF732FCCu,
+            accentAlt = 0xFF1856D1u,
+            accentDim = 0xFFC4BBE4u,
+            onAccent = 0xFFEFF1F5u,
+            danger = 0xFFD20F39u,
+            elevated = 0xFFAAAEBDu,
+            dangerDim = 0xFFE7D1D5u,
+            light = true,
+        )
+
+        fun episode(season: UInt, number: UInt, watched: Boolean = false, progress: Double? = null): EpisodeRecord {
+            // `detail` is the filename unless the filename named the episode,
+            // which is what the bridge sends.
+            val file = "[Group] Oshi no Ko - S%02dE%02d.mkv".format(season.toInt(), number.toInt())
+            return episodeRecord(season, number, file, watched, progress)
+        }
+
+        fun episodeRecord(season: UInt, number: UInt, file: String, watched: Boolean, progress: Double?) = EpisodeRecord(
+            shareId = "share",
+            volumeId = "volume",
+            linkId = "s${season}e$number",
+            name = file,
+            label = "S%02dE%02d".format(season.toInt(), number.toInt()),
+            detail = file,
+            season = season,
+            number = number,
+            size = 1_300_000_000uL,
+            progress = progress,
+            resumeAt = progress?.let { it * 1440 },
+            watched = watched,
+            offline = false,
+            providerName = if (number == 1u) "Mother and Children" else null,
+            providerOverview = null,
+            stillUrl = null,
+            airDate = null,
+            // 2026-09-21 for the part-watched one, the day before for the rest.
+            lastPlayed = when {
+                progress != null -> 1_790_000_000L
+                watched -> 1_789_900_000L - number.toLong() * 600
+                else -> 0L
+            },
+        )
+
+        fun title(key: String, name: String, seasons: List<SeasonRecord>, overview: String? = null) = TitleRecord(
+            key = key,
+            name = name,
+            year = 2023u,
+            kind = TitleType.SERIES,
+            watchedCount = seasons.sumOf { s -> s.episodes.count { it.watched } }.toULong(),
+            episodeCount = seasons.sumOf { it.episodes.size }.toULong(),
+            canonicalName = null,
+            originalName = null,
+            overview = overview,
+            metadataProvider = null,
+            metadataId = null,
+            metadataYear = null,
+            metadataKind = null,
+            posterUrl = null,
+            backdropUrl = null,
+            rating = 8.4,
+            genres = listOf("Drama", "Mystery"),
+            providerEpisodeCount = null,
+            externalUrl = null,
+            manualMatch = false,
+            seasons = seasons,
+            displayName = name,
+            wideUrl = null,
+            formatLabel = null,
+            seasonLabel = null,
+            studios = emptyList(),
+            directors = emptyList(),
+            tags = emptyList(),
+            airing = false,
+            nextEpisode = null,
+            nextAiringAt = null,
+            franchise = emptyList(),
+            // What the engine would pick for these fixtures: the part-watched episode.
+            continueIndex = seasons.flatMap { it.episodes }.indexOfFirst { it.resumeAt != null }
+                .takeIf { it >= 0 }?.toUInt(),
+        )
+
+        val SERIES = title(
+            "oshi-no-ko",
+            "Oshi no Ko",
+            listOf(
+                SeasonRecord(1u, "Season 1", (1u..4u).map { episode(1u, it, watched = it < 3u) }),
+                SeasonRecord(2u, "Season 2", (1u..3u).map { episode(2u, it, progress = if (it == 1u) 0.4 else null) }),
+            ),
+            overview = "A doctor in a countryside clinic is reborn as the child of the idol he followed.",
+        ).copy(
+            formatLabel = "TV",
+            seasonLabel = "Spring 2023",
+            studios = listOf("Doga Kobo"),
+            directors = listOf("Daisuke Hiramaki"),
+            tags = listOf("Idol", "Reincarnation"),
+            franchise = listOf("oshi-no-ko", "oshi-no-ko-film"),
+        )
+
+        /** The rest of [SERIES]'s franchise, for the title page's row of it. */
+        val SEQUEL = title("oshi-no-ko-film", "Oshi no Ko: The Final Act", listOf(SeasonRecord(null, "Film", listOf(episode(1u, 1u)))))
+            .copy(kind = TitleType.FILM, year = 2024u, formatLabel = "Film", franchise = SERIES.franchise)
+
+        val FILM = title("akira", "Akira", listOf(SeasonRecord(null, "Film", listOf(episode(1u, 1u)))))
+            .copy(kind = TitleType.FILM, year = 1988u)
+
+        /** [LIBRARY] with posters on, as the shelf above its grid implies. */
+        val MATCHED get() = LIBRARY.copy(
+            metadataSettings = MetadataSettingsRecord(
+                enabled = true,
+                provider = MetadataProvider.ANI_LIST,
+                language = "en",
+                ready = true,
+            ),
+        )
+
+        val LIBRARY = AppUiState(
+            loading = false,
+            titles = listOf(
+                FILM,
+                SERIES,
+                title("ano-hana", "Ano Hi Mita Hana no Namae o Bokutachi wa Mada Shiranai.", listOf(SeasonRecord(1u, "Season 1", (1u..11u).map { episode(1u, it) }))),
+                title("bleach", "Bleach", listOf(SeasonRecord(1u, "Season 1", (1u..2u).map { episode(1u, it) }))),
+            ),
+            // Bleach stands for one more title of its franchise, and one shelf
+            // sits above the grid: what the bridge's arrangement would give.
+            arrangement = ArrangementRecord(
+                tiles = listOf("akira", "ano-hana", "bleach", "oshi-no-ko").map {
+                    TileRecord(it, if (it == "bleach") 1u else 0u)
+                },
+                shelves = listOf(ShelfRecord("From MAPPA", listOf("oshi-no-ko", "bleach", "akira"))),
+            ),
+            // Crawled relative to the clock, so the row reads "2 h ago" on
+            // whatever day the test runs.
+            shares = listOf(
+                ShareRecord(
+                    "anime",
+                    "anime",
+                    true,
+                    crawledAt = System.currentTimeMillis() / 1_000 - 2 * 3_600,
+                    crawlFiles = 120uL,
+                ),
+                ShareRecord("films", "films", false, crawlError = "the link was revoked or has expired"),
+            ),
+            storage = StorageUsageRecord(6_400_000_000uL, 3uL, 0uL, 1_100_000_000uL),
+        )
+    }
+}

android/app/src/test/java/io/narl/protonstream/ui/theme/SchemeRolesTest.kt

@@ -0,0 +1,129 @@
+package io.narl.protonstream.ui.theme
+
+import androidx.compose.material3.ColorScheme
+import androidx.compose.material3.darkColorScheme
+import androidx.compose.material3.lightColorScheme
+import androidx.compose.ui.graphics.Color
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertTrue
+import org.junit.Test
+import uniffi.pstr_android.PaletteRecord
+
+/**
+ * That every Material colour role is answered by the palette.
+ *
+ * Material names roughly fifty roles and a `ColorScheme` is built by copying a
+ * baseline, so a role nobody names keeps Material's own purple-and-grey —
+ * silently, and only where that particular role happens to be drawn. That is
+ * how `surfaceContainerHighest` went unnoticed: nothing referred to it by name,
+ * but it is what `Card` fills with, so every tile, episode row, share and
+ * download in the app was baseline neutral on a flavoured page.
+ *
+ * The check is reflective rather than a list, because a list is exactly as
+ * incomplete as the mapping it was written from — and because Material adds
+ * roles between versions, and a role added tomorrow should fail this the day
+ * the dependency moves.
+ */
+class SchemeRolesTest {
+    /**
+     * A palette whose every colour is distinct and none of which Material would
+     * ever produce, so that "this role came from the palette" is decidable by
+     * looking at the value.
+     */
+    private fun sentinels(light: Boolean) = PaletteRecord(
+        background = 0xFF010203u,
+        surface = 0xFF040506u,
+        sunken = 0xFF070809u,
+        card = 0xFF0A0B0Cu,
+        cardHover = 0xFF0D0E0Fu,
+        border = 0xFF101112u,
+        text = 0xFF131415u,
+        muted = 0xFF161718u,
+        accent = 0xFF191A1Bu,
+        accentAlt = 0xFF1C1D1Eu,
+        accentDim = 0xFF1F2021u,
+        onAccent = 0xFF222324u,
+        danger = 0xFF252627u,
+        elevated = 0xFF28292Au,
+        dangerDim = 0xFF2B2C2Du,
+        light = light,
+    )
+
+    /** Every role on a `ColorScheme`, read by name, whatever the version names. */
+    private fun roles(scheme: ColorScheme): Map<String, Color> =
+        ColorScheme::class.java.declaredMethods
+            .filter { it.name.startsWith("get") && it.parameterCount == 0 && it.returnType == Long::class.java }
+            .associate { method ->
+                method.isAccessible = true
+                // Kotlin mangles the getter of a value-class property:
+                // `getPrimary-0d7_KjU`. The property is what the name says up
+                // to the dash.
+                method.name.removePrefix("get").substringBefore('-') to
+                    Color((method.invoke(scheme) as Long).toULong())
+            }
+
+    @Test
+    fun `every role is answered by the palette`() {
+        for (light in listOf(false, true)) {
+            val palette = sentinels(light)
+            val allowed = buildSet {
+                addAll(
+                    listOf(
+                        palette.background, palette.surface, palette.sunken, palette.card,
+                        palette.cardHover, palette.border, palette.text, palette.muted,
+                        palette.accent, palette.accentAlt, palette.accentDim, palette.onAccent,
+                        palette.danger, palette.elevated, palette.dangerDim,
+                    ).map { Color(it.toInt()) },
+                )
+                // The two roles that are deliberately not a palette colour: no
+                // elevation tint at all, and a scrim that is an absence of
+                // light rather than a hue.
+                add(Color.Transparent)
+                add(Color.Black)
+            }
+
+            val leaked = roles(schemeOf(palette)).filterValues { it !in allowed }
+            assertTrue(
+                "light=$light: ${leaked.keys.sorted()} still carry Material's baseline",
+                leaked.isEmpty(),
+            )
+        }
+    }
+
+    /**
+     * The count is asserted too. A reflective sweep that found no roles at all
+     * would pass the check above for the wrong reason.
+     */
+    @Test
+    fun `the sweep sees the whole scheme`() {
+        val count = roles(darkColorScheme()).size
+        assertTrue("only $count roles found; the reflective sweep is not working", count >= 40)
+        assertEquals(count, roles(lightColorScheme()).size)
+    }
+
+    /**
+     * Which baseline was copied stops being observable once every role is
+     * mapped — and that is the point.
+     *
+     * `light` still decides plenty, but it decides it in Rust, where it picks
+     * the flavour's colours. By the time a palette reaches Kotlin the
+     * light-or-dark question is already answered *inside* the colours, so two
+     * palettes that differ only in the flag have to produce the same scheme. If
+     * they ever stop doing so, something is reading `light` here rather than
+     * reading the colours.
+     */
+    @Test
+    fun `the baseline no longer shows through`() {
+        assertEquals(roles(schemeOf(sentinels(false))), roles(schemeOf(sentinels(true))))
+        assertEquals(Color.Transparent, schemeOf(sentinels(false)).surfaceTint)
+    }
+
+    /** The fallback goes through the same mapping as any other palette. */
+    @Test
+    fun `the shipped fallback is fully mapped too`() {
+        val scheme = schemeOf(ProtonFallback)
+        assertEquals(Color(ProtonFallback.elevated.toInt()), scheme.surfaceContainerHighest)
+        assertEquals(Color(ProtonFallback.card.toInt()), scheme.surfaceContainer)
+        assertEquals(Color(ProtonFallback.dangerDim.toInt()), scheme.errorContainer)
+    }
+}

android/app/src/test/java/io/narl/protonstream/ui/theme/TypeRampTest.kt

@@ -0,0 +1,109 @@
+package io.narl.protonstream.ui.theme
+
+import androidx.compose.material3.Typography
+import androidx.compose.ui.text.TextStyle
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+/**
+ * That the type ramp is the ramp, and the corner radius is the radius.
+ *
+ * The two clients share a palette because one Rust function resolves it for
+ * both. Type and shape have no such bridge — they are named in
+ * `pstr_app::theme::Role` and copied here — so what stops them drifting is this
+ * test and the numbers in it. Change the Rust ramp and this fails; that is the
+ * point of it.
+ *
+ * Every style is named rather than checked against a set, because "some rung"
+ * is not the property that matters: `bodyMedium`'s Material default is 14sp,
+ * which is a rung, so a `bodyMedium` nobody mapped would pass a looser check
+ * while sitting one step off where it belongs.
+ */
+class TypeRampTest {
+    /** `Role::size()`, in the order `theme.rs` declares it. */
+    private val ramp = listOf(26f, 20f, 18f, 17f, 15f, 14f, 13f, 12f, 11f)
+
+    private val expected = mapOf(
+        "displayLarge" to 26f,
+        "displayMedium" to 26f,
+        "displaySmall" to 20f,
+        "headlineLarge" to 26f,
+        "headlineMedium" to 26f,
+        "headlineSmall" to 18f,
+        "titleLarge" to 20f,
+        "titleMedium" to 17f,
+        "titleSmall" to 15f,
+        "bodyLarge" to 14f,
+        "bodyMedium" to 13f,
+        "bodySmall" to 12f,
+        "labelLarge" to 13f,
+        "labelMedium" to 12f,
+        "labelSmall" to 11f,
+    )
+
+    @Test
+    fun `every text style sits on the shared ramp`() {
+        expected.forEach { (name, size) ->
+            assertEquals(name, size, styles().getValue(name).fontSize.value, 0.001f)
+        }
+    }
+
+    /**
+     * Material adds type styles between versions, and one added tomorrow would
+     * arrive at whatever size Material chose for it. The list above is only as
+     * complete as the day it was written unless something says so.
+     */
+    @Test
+    fun `no text style is left at Material's own size`() {
+        assertEquals(expected.keys, styles().keys)
+    }
+
+    /**
+     * Leading is derived from the size, so the only thing worth asserting is
+     * that it *was* derived — a style that kept Material's line height carries
+     * a number with no relation to its own size.
+     */
+    @Test
+    fun `line height follows the size it belongs to`() {
+        styles().forEach { (name, style) ->
+            assertEquals(name, style.fontSize.value * 1.35f, style.lineHeight.value, 0.01f)
+        }
+    }
+
+    @Test
+    fun `the ramp has no rung the styles never reach`() {
+        val drawn = styles().values.map { it.fontSize.value }.toSet()
+        ramp.forEach { rung -> assertTrue("$rung is named but never drawn", rung in drawn) }
+    }
+
+    @Test
+    fun `every surface is drawn at the desktop's radius`() {
+        listOf(ProtonShapes.small, ProtonShapes.medium, ProtonShapes.large).forEach { shape ->
+            // `CornerSize` resolves against a size and a density, and neither is
+            // available to a unit test; `toString` is the only handle on the
+            // value that does not need a composition.
+            assertTrue("$shape is not radius $CORNER", shape.toString().contains("$CORNER"))
+        }
+    }
+
+    /**
+     * Every text style a caller can set, read by name, whatever the version
+     * names.
+     *
+     * Material 1.4 carries a second, `Emphasized` copy of all fifteen for its
+     * expressive components. Those are `internal` — the constructor takes them
+     * but Kotlin will not let this module pass them — so they keep Material's
+     * own sizes and nothing here can do anything about it. Their getters are
+     * name-mangled with `$material3`, which is how they are told apart from a
+     * public style that genuinely went unmapped.
+     */
+    private fun styles(): Map<String, TextStyle> = Typography::class.java.declaredMethods
+        .filter { it.parameterCount == 0 && it.returnType == TextStyle::class.java }
+        .filterNot { '$' in it.name }
+        .associate { method ->
+            method.isAccessible = true
+            method.name.removePrefix("get").replaceFirstChar(Char::lowercaseChar) to
+                method.invoke(ProtonTypography) as TextStyle
+        }
+}

android/app/src/test/resources/robolectric.properties

@@ -0,0 +1,11 @@
+# Robolectric ships no Android image for API 36 yet, and defaults to the app's
+# targetSdk, so host tests would fail to start. 34 is the newest it has and is
+# well above minSdk 31; anything whose behaviour actually turns on the API level
+# belongs in androidTest, on a real device, not here.
+sdk=34
+
+# ProtonStreamApplication.onCreate() calls System.loadLibrary("pstr_android"),
+# which has no host build. Host tests get a plain Application; everything that
+# needs the bridge is an instrumentation test by construction — see
+# androidTest/.../UniFfiBoundaryTest.
+application=android.app.Application

android/gradle/libs.versions.toml

@@ -6,10 +6,15 @@ activity = "1.11.0"
 lifecycle = "2.9.4"
 navigation = "2.9.5"
 work = "2.10.5"
-media3 = "1.8.0"
 adaptive = "1.1.0"
 jna = "5.17.0"
 junit = "4.13.2"
+robolectric = "4.16"
+androidx-test-core = "1.7.0"
+androidx-test-junit = "1.3.0"
+androidx-test-runner = "1.7.0"
+ktlint-plugin = "13.1.0"
+roborazzi = "1.76.0"
 
 [libraries]
 androidx-core = { module = "androidx.core:core-ktx", version = "1.17.0" }
@@ -18,8 +23,7 @@ androidx-lifecycle-runtime = { module = "androidx.lifecycle:lifecycle-runtime-kt
 androidx-lifecycle-viewmodel-compose = { module = "androidx.lifecycle:lifecycle-viewmodel-compose", version.ref = "lifecycle" }
 androidx-navigation-compose = { module = "androidx.navigation:navigation-compose", version.ref = "navigation" }
 androidx-work-runtime = { module = "androidx.work:work-runtime-ktx", version.ref = "work" }
-androidx-media3-session = { module = "androidx.media3:media3-session", version.ref = "media3" }
+androidx-work-testing = { module = "androidx.work:work-testing", version.ref = "work" }
-androidx-media3-exoplayer = { module = "androidx.media3:media3-exoplayer", version.ref = "media3" }
 androidx-compose-bom = { module = "androidx.compose:compose-bom", version.ref = "compose-bom" }
 androidx-compose-ui = { module = "androidx.compose.ui:ui" }
 androidx-compose-ui-tooling = { module = "androidx.compose.ui:ui-tooling" }
@@ -29,11 +33,22 @@ androidx-compose-material3 = { module = "androidx.compose.material3:material3" }
 androidx-compose-material3-adaptive = { module = "androidx.compose.material3.adaptive:adaptive", version.ref = "adaptive" }
 androidx-compose-material3-navigation-suite = { module = "androidx.compose.material3:material3-adaptive-navigation-suite", version.ref = "adaptive" }
 androidx-compose-material-icons-extended = { module = "androidx.compose.material:material-icons-extended" }
+androidx-compose-ui-test-junit4 = { module = "androidx.compose.ui:ui-test-junit4" }
+androidx-compose-ui-test-manifest = { module = "androidx.compose.ui:ui-test-manifest" }
 jna = { module = "net.java.dev.jna:jna", version.ref = "jna" }
 rustls-platform-verifier = { module = "rustls:rustls-platform-verifier", version = "0.1.1" }
 junit = { module = "junit:junit", version.ref = "junit" }
+robolectric = { module = "org.robolectric:robolectric", version.ref = "robolectric" }
+androidx-test-core = { module = "androidx.test:core-ktx", version.ref = "androidx-test-core" }
+androidx-test-junit = { module = "androidx.test.ext:junit", version.ref = "androidx-test-junit" }
+androidx-test-runner = { module = "androidx.test:runner", version.ref = "androidx-test-runner" }
+roborazzi = { module = "io.github.takahirom.roborazzi:roborazzi", version.ref = "roborazzi" }
+roborazzi-compose = { module = "io.github.takahirom.roborazzi:roborazzi-compose", version.ref = "roborazzi" }
+roborazzi-junit-rule = { module = "io.github.takahirom.roborazzi:roborazzi-junit-rule", version.ref = "roborazzi" }
 
 [plugins]
 android-application = { id = "com.android.application", version.ref = "agp" }
 kotlin-android = { id = "org.jetbrains.kotlin.android", version.ref = "kotlin" }
 kotlin-compose = { id = "org.jetbrains.kotlin.plugin.compose", version.ref = "kotlin" }
+ktlint = { id = "org.jlleitschuh.gradle.ktlint", version.ref = "ktlint-plugin" }
+roborazzi = { id = "io.github.takahirom.roborazzi", version.ref = "roborazzi" }

crates/pstr-android/Cargo.toml

@@ -24,11 +24,13 @@ pstr-core.workspace = true
 pstr-meta.workspace = true
 pstr-stream.workspace = true
 tokio.workspace = true
+futures.workspace = true
 parking_lot.workspace = true
 thiserror.workspace = true
 uniffi.workspace = true
 serde.workspace = true
 serde_json.workspace = true
+log = "0.4"
 
 [target.'cfg(target_os = "android")'.dependencies]
 # Match rustls-platform-verifier's JNI types: Java objects from different
@@ -36,4 +38,3 @@ serde_json.workspace = true
 jni = "0.21.1"
 rustls-platform-verifier = "0.6.2"
 android_logger = "0.14"
-log = "0.4"