feat(app): desktop notifications, paste a share link anywhere

- a finished batch of downloads, and a crawl long enough to walk away
  from, notify through org.freedesktop.Notifications when the window is
  not focused; once per batch, not once per file
- Ctrl+V with a share link outside a text field opens the add form
  with the link in it

crates/pstr-app/src/app.rs

@@ -105,6 +105,8 @@ pub enum Action {
     Crawl(Option<String>),
     /// Stop the crawls still listing.
     StopCrawl,
+    /// A share link was pasted outside the form: open the form with it.
+    PasteShare(String),
     AddShare {
         name: String,
         url: String,
@@ -434,6 +436,7 @@ pub struct App {
     media_cover: Option<(u64, Option<String>)>,
     /// Holds the screensaver off while a film is on screen and playing.
     inhibitor: crate::inhibit::Inhibitor,
+    notifier: crate::notify::Notifier,
     pub downloads: Vec<DownloadItem>,
     pub offline_files: std::collections::HashSet<DownloadKey>,
     pub confirm_partial_delete: Option<DownloadKey>,
@@ -503,6 +506,7 @@ impl App {
             media: crate::media::MediaSession::new(&cc.egui_ctx, window_handle(cc)),
             media_cover: None,
             inhibitor: crate::inhibit::Inhibitor::new(),
+            notifier: crate::notify::Notifier::new(),
             downloads: Vec::new(),
             offline_files: std::collections::HashSet::new(),
             confirm_partial_delete: None,
@@ -573,6 +577,10 @@ impl App {
                         format!("{name}: {files} playable of {nodes} nodes in {seconds:.0}s"),
                         false,
                     );
+                    // Only a crawl long enough to have walked away from.
+                    if seconds >= 30.0 {
+                        self.notify(ctx, &format!("Crawled {name}"), &format!("{files} files"));
+                    }
                 }
                 Event::CrawlFinished => {
                     self.crawling = false;
@@ -582,6 +590,21 @@ impl App {
                     self.crawling = true;
                     self.crawl_progress.insert(share, found);
                 }
+                Event::Downloaded(name) => {
+                    self.note(ctx, format!("{name} is available offline"), false);
+                    // Once per batch, when the last of it lands: a season is
+                    // two dozen files, and two dozen notifications is spam.
+                    let more = self.downloads.iter().any(|item| {
+                        matches!(
+                            item.state,
+                            crate::engine::DownloadState::Queued
+                                | crate::engine::DownloadState::Running
+                        )
+                    });
+                    if !more {
+                        self.notify(ctx, "Downloads finished", &name);
+                    }
+                }
                 Event::CrawlStopped { share_id } => {
                     let name = self.share_name(&share_id);
                     self.crawl_progress.remove(&name);
@@ -777,6 +800,15 @@ impl App {
         cover
     }
 
+    /// A desktop notification, if the window is not what the viewer is
+    /// looking at. When it is, the toast already said it.
+    fn notify(&self, ctx: &egui::Context, summary: &str, body: &str) {
+        let focused = ctx.input(|input| input.viewport().focused.unwrap_or(true));
+        if !focused {
+            self.notifier.send(summary, body);
+        }
+    }
+
     fn share_name(&self, id: &str) -> String {
         self.shares
             .iter()
@@ -1125,6 +1157,12 @@ impl App {
                 self.engine.crawl(share);
             }
             Action::StopCrawl => self.engine.stop_crawl(),
+            Action::PasteShare(url) => {
+                self.page = Page::Shares;
+                self.form.url = url;
+                self.form.error = None;
+                self.note(ctx, "share link pasted — name it and add it", false);
+            }
             Action::AddShare {
                 name,
                 url,
@@ -1807,6 +1845,17 @@ fn global_shortcuts(ctx: &egui::Context, page: &Page, actions: &mut Vec<Action>)
         if input.consume_key(Modifiers::COMMAND, Key::Comma) {
             tab = Some(3);
         }
+        // A share link pasted anywhere outside a text field is someone adding
+        // a share, wherever they happen to be.
+        if !typing {
+            for event in &input.events {
+                if let egui::Event::Paste(text) = event
+                    && pstr_core::shares::share_token(text.trim()).is_ok()
+                {
+                    actions.push(Action::PasteShare(text.trim().to_owned()));
+                }
+            }
+        }
     });
     if let Some(index) = tab {
         let page = [Page::Library, Page::Shares, Page::Downloads, Page::Settings][index].clone();

crates/pstr-app/src/engine.rs

@@ -186,6 +186,8 @@ pub enum Event {
     CrawlProgress { share: String, found: usize },
     /// Every requested crawl is done.
     CrawlFinished,
+    /// A download finished; this is what it was.
+    Downloaded(String),
     /// That share's crawl was stopped before it stored anything.
     CrawlStopped { share_id: String },
     /// A decoded Proton thumbnail, keyed as [`thumbnail_key`].
@@ -1145,10 +1147,7 @@ impl Engine {
                         item.state = DownloadState::Completed;
                     });
                     engine.load_offline_files();
-                    engine.emit(Event::Status(format!(
+                    engine.emit(Event::Downloaded(task_target.caption_or_name()));
-                        "{} is available offline",
-                        task_target.name
-                    )));
                 }
                 Ok(DownloadEnd::Cancelled) => {
                     engine.update_download(&task_key, |item| item.state = DownloadState::Cancelled);

crates/pstr-app/src/lib.rs

@@ -23,6 +23,7 @@ pub mod app;
 pub mod engine;
 pub mod inhibit;
 pub mod media;
+pub mod notify;
 pub mod pacing;
 pub mod playback;
 pub mod theme;

crates/pstr-app/src/notify.rs

@@ -0,0 +1,95 @@
+//! Desktop notifications, for things that finish while nobody is looking.
+//!
+//! Only when the window does not have focus: a viewer who is looking at the
+//! app already has the toast, and a second copy of it from the panel is noise.
+//! That rule is the caller's — see `App::notify`.
+//!
+//! Linux only, over `org.freedesktop.Notifications`. Windows wants an
+//! application id registered by an installer before a toast will show, and a
+//! notification that silently never appears is worse than none.
+
+/// Sends notifications from a thread of its own, so a notification daemon
+/// that is slow to answer never costs a frame.
+pub struct Notifier {
+    #[cfg(target_os = "linux")]
+    orders: Option<std::sync::mpsc::Sender<(String, String)>>,
+}
+
+impl Notifier {
+    pub fn new() -> Self {
+        Self {
+            #[cfg(target_os = "linux")]
+            orders: linux::spawn(),
+        }
+    }
+
+    pub fn send(&self, summary: impl Into<String>, body: impl Into<String>) {
+        #[cfg(target_os = "linux")]
+        if let Some(orders) = &self.orders {
+            let _ = orders.send((summary.into(), body.into()));
+        }
+        #[cfg(not(target_os = "linux"))]
+        let _ = (summary.into(), body.into());
+    }
+}
+
+impl Default for Notifier {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+#[cfg(target_os = "linux")]
+mod linux {
+    use std::sync::mpsc::{Sender, channel};
+    use std::time::Duration;
+
+    use dbus::arg::PropMap;
+    use dbus::blocking::Connection;
+
+    pub fn spawn() -> Option<Sender<(String, String)>> {
+        let (orders, receiver) = channel::<(String, String)>();
+        std::thread::Builder::new()
+            .name("notify".into())
+            .spawn(move || {
+                // Connected on first use rather than at startup: most sessions
+                // never send one.
+                let mut connection: Option<Connection> = None;
+                for (summary, body) in receiver {
+                    if connection.is_none() {
+                        connection = Connection::new_session()
+                            .inspect_err(|error| tracing::debug!("notifications: {error}"))
+                            .ok();
+                    }
+                    let Some(connection) = &connection else {
+                        continue;
+                    };
+                    let proxy = connection.with_proxy(
+                        "org.freedesktop.Notifications",
+                        "/org/freedesktop/Notifications",
+                        Duration::from_secs(2),
+                    );
+                    let answer: Result<(u32,), _> = proxy.method_call(
+                        "org.freedesktop.Notifications",
+                        "Notify",
+                        (
+                            "proton-stream",
+                            0u32,
+                            "io.narl.proton-stream",
+                            summary,
+                            body,
+                            Vec::<String>::new(),
+                            PropMap::new(),
+                            -1i32,
+                        ),
+                    );
+                    if let Err(error) = answer {
+                        tracing::debug!("notification: {error}");
+                    }
+                }
+            })
+            .inspect_err(|error| tracing::debug!("notify thread: {error}"))
+            .ok()?;
+        Some(orders)
+    }
+}

crates/pstr-app/src/playback.rs

@@ -110,6 +110,16 @@ impl PlaybackTarget {
 
     /// The line under the title while this plays: the numbering, and the
     /// episode's name when a provider has given one.
+    /// How to name this file to someone not looking at its title page:
+    /// the title and the episode, or the file name when there is no title.
+    pub fn caption_or_name(&self) -> String {
+        match (self.title_name.is_empty(), self.caption()) {
+            (false, caption) if !caption.is_empty() => format!("{} — {caption}", self.title_name),
+            (false, _) => self.title_name.clone(),
+            (true, _) => self.name.clone(),
+        }
+    }
+
     pub fn caption(&self) -> String {
         match &self.episode_name {
             Some(name) if !self.subtitle.is_empty() => format!("{}  ·  {name}", self.subtitle),

crates/pstr-app/src/ui/shortcuts.rs

@@ -15,6 +15,7 @@ const GROUPS: &[(&str, &[(&str, &str)])] = &[
             ("F5  or  Ctrl R", "Crawl every share again"),
             ("Ctrl 1 – 4", "Library, Shares, Downloads, Settings"),
             ("Ctrl ,", "Settings"),
+            ("Ctrl V", "Paste a share link to add it"),
             ("Alt ←  or  mouse back", "Back"),
             ("?", "This list"),
         ],