feat(android): a history page

History sits second in the navigation, as on the desktop: every played
episode, newest first, under Today, Yesterday, a weekday or a date. The
still plays the episode, the text opens its title, and the cross takes
it off the page — forgetting its position and watched mark — with Undo.

The list is the desktop's Library::history rule over the records the
library already holds, so no bridge call is added; HistoryTest pins the
rule and the day headings.

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

@@ -231,6 +231,19 @@ class AppViewModel(context: Context, private val workManager: WorkManager) : Vie
         }
     }
 
+    /**
+     * 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.canonicalName ?: title.name} 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

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

@@ -0,0 +1,178 @@
+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()) {
+        Box(Modifier.fillMaxSize().padding(padding)) {
+            EmptyState("Nothing watched yet", "Episodes you play show up here, newest first.")
+        }
+        return
+    }
+    LazyColumn(Modifier.fillMaxSize().padding(padding), 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,
+            )
+            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.canonicalName ?: entry.title.name,
+                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/ProtonStreamApp.kt

@@ -33,6 +33,7 @@ import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.VideoLibrary
 import androidx.compose.material.icons.filled.Share
 import androidx.compose.material.icons.filled.Download
+import androidx.compose.material.icons.filled.History
 import androidx.compose.material.icons.filled.Settings
 import androidx.compose.material.icons.filled.Refresh
 import androidx.compose.material.icons.filled.Close
@@ -79,6 +80,7 @@ private data class PlayRequest(
 
 private enum class Destination(val label: String, val icon: ImageVector) {
     Library("Library", Icons.Default.VideoLibrary),
+    History("History", Icons.Default.History),
     Shares("Shares", Icons.Default.Share),
     Downloads("Downloads", Icons.Default.Download),
     Settings("Settings", Icons.Default.Settings),
@@ -239,6 +241,17 @@ fun ProtonStreamApp(
                         onShareLinkTaken,
                         body,
                     )
+                    Destination.History -> HistoryScreen(
+                        state,
+                        { title, index ->
+                            playingTitleKey = title.key
+                            playingIndex = index
+                            playerMinimized = false
+                        },
+                        { destination = Destination.Library; selectedTitleKey = it.key },
+                        model::removeFromHistory,
+                        body,
+                    )
                     Destination.Downloads -> DownloadsScreen(
                         state,
                         model::removeOffline,

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

@@ -0,0 +1,55 @@
+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())),
+    )
+
+    @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/ScreenshotTest.kt

@@ -14,6 +14,8 @@ import androidx.work.testing.WorkManagerTestInitHelper
 import com.github.takahirom.roborazzi.RobolectricDeviceQualifiers
 import com.github.takahirom.roborazzi.captureRoboImage
 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
@@ -98,6 +100,13 @@ class ScreenshotTest {
         SettingsScreen(LIBRARY, { _, _, _, _ -> }, {}, {}, {}, PaddingValues())
     }
 
+    @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 nothing offline`() = capture("downloads-empty") {
         DownloadsScreen(LIBRARY, {}, {}, {}, {}, PaddingValues())
@@ -129,7 +138,12 @@ class ScreenshotTest {
             providerOverview = null,
             stillUrl = null,
             airDate = null,
-            lastPlayed = if (progress != null) 1_790_000_000L else 0L,
+            // 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(

docs/TESTING.md

@@ -213,7 +213,7 @@ across fails here rather than being noticed in a screenshot.
 
 **Screenshot tests** (`ScreenshotTest`, Roborazzi) draw each screen from fixed
 records — Library on a phone, a tablet and at font scale 1.5, an empty library,
-a title, Shares, Settings and Downloads — and `check` compares them with the
+a title, History, Shares, Settings and Downloads — and `check` compares them with the
 images in `app/src/test/screenshots`. A layout regression compiles and passes
 everything else; here it fails, and the review shows the changed image. After a
 deliberate change, `gradlew recordRoborazziDebug` rewrites the images and they