feat: open selected YouTube video in browser

src/keys.rs

@@ -119,6 +119,7 @@ actions! {
     ViewTabPrevious, "view.tab.previous", "Select the previous view tab", VIEW, ["shift+tab"];
     ViewRefresh, "view.refresh", "Refresh the current view and configuration", VIEW, ["r"];
     VideoPlay, "video.play", "Play the selected video", VIEW, ["enter"];
+    VideoOpen, "video.open", "Open the selected YouTube video in the default browser", VIEW, ["o"];
     VideoNext, "video.select.next", "Select the next video", VIEW, ["j", "down", "ctrl+j"];
     VideoPrevious, "video.select.previous", "Select the previous video", VIEW, ["k", "up", "ctrl+k"];
     VideoFirst, "video.select.first", "Select the first video", VIEW, ["g", "home"];
@@ -479,6 +480,10 @@ impl Bindings {
                 &[
                     (&[VideoNext, VideoPrevious], "Select next / previous video"),
                     (&[VideoPlay], "Play the selected video in Terebi"),
+                    (
+                        &[VideoOpen],
+                        "Open the selected YouTube video in the default browser",
+                    ),
                     (
                         &[WatchStatusWatching],
                         "Mark selected as watching (clear watched)",

src/main.rs

@@ -948,6 +948,7 @@ struct App {
     description_viewport: Option<(u16, u16)>,
     job: Option<Job>,
     player_launch: Option<PlayerLaunch>,
+    browser_launch: Option<std::sync::mpsc::Receiver<Result<(), String>>>,
     status: String,
 }
 
@@ -1023,6 +1024,7 @@ impl App {
             description_viewport: None,
             job: None,
             player_launch: None,
+            browser_launch: None,
             status: "Enter a query to search YouTube.".into(),
         }
     }
@@ -2553,6 +2555,24 @@ impl App {
         }
     }
 
+    fn open_video_in_browser(&mut self) {
+        let view = &self.views[self.view_index];
+        let Some(video) = view
+            .selection
+            .selected()
+            .and_then(|index| view.videos.get(index))
+        else {
+            return;
+        };
+        match youtube::open_in_browser(&video.id) {
+            Ok(launch) => {
+                self.browser_launch = Some(launch);
+                self.status = format!("Opening {} in the default browser...", video.title);
+            }
+            Err(error) => self.status = error.to_string(),
+        }
+    }
+
     fn finish_description(&mut self, id: String, result: Result<String, String>) {
         match result.and_then(|output| youtube::full_description(&output, &id)) {
             Ok(description) => self.remember_description(id, description),
@@ -2601,6 +2621,17 @@ impl App {
                 Err(error) => error,
             };
         }
+        if let Some(result) = self
+            .browser_launch
+            .as_ref()
+            .and_then(|launch| launch.try_recv().ok())
+        {
+            self.browser_launch = None;
+            self.status = match result {
+                Ok(()) => "Video handed to the default browser.".into(),
+                Err(error) => error,
+            };
+        }
         match self.video_state.poll_progress() {
             Ok(true) => {
                 self.rebuild_collections();
@@ -2869,6 +2900,7 @@ impl App {
                     self.browse_category_collection(CollectionKind::Saved)
                 }
                 Some(Action::VideoPlay) => self.play(),
+                Some(Action::VideoOpen) => self.open_video_in_browser(),
                 Some(Action::VideoNext) => {
                     self.views[self.view_index].prefetch_requested = true;
                     self.views[self.view_index].selection.select_next();

src/youtube.rs

@@ -805,6 +805,52 @@ fn failure(errors: &Receiver<io::Result<String>>, fallback: String) -> Option<Re
     }
 }
 
+pub fn open_in_browser(id: &str) -> io::Result<Receiver<Result<(), String>>> {
+    if !valid_video_id(id) {
+        return Err(io::Error::new(
+            io::ErrorKind::InvalidInput,
+            "Invalid YouTube video ID",
+        ));
+    }
+    let opener = if cfg!(target_os = "macos") {
+        "open"
+    } else {
+        "xdg-open"
+    };
+    let child = isolated_command(OsStr::new(opener))
+        .arg(format!("https://www.youtube.com/watch?v={id}"))
+        .stdin(Stdio::null())
+        .stdout(Stdio::null())
+        .stderr(Stdio::piped())
+        .spawn()
+        .map_err(|error| {
+            io::Error::new(
+                error.kind(),
+                format!("Cannot start browser opener: {error}"),
+            )
+        })?;
+    let (sender, receiver) = mpsc::channel();
+    thread::spawn(move || {
+        let result = child
+            .wait_with_output()
+            .map_err(|error| format!("Cannot wait for browser opener: {error}"))
+            .and_then(|output| {
+                if output.status.success() {
+                    Ok(())
+                } else {
+                    let error = String::from_utf8_lossy(&output.stderr);
+                    Err(format!(
+                        "Browser opener exited with {}: {}",
+                        output.status,
+                        error.trim()
+                    ))
+                }
+            });
+        let _ = sender.send(result);
+    });
+    Ok(receiver)
+}
+
 pub struct PlayerLaunch {
     player: Child,
     player_errors: Receiver<io::Result<String>>,
@@ -1465,6 +1511,16 @@ mod tests {
         }
     }
 
+    #[test]
+    fn browser_open_rejects_unsafe_video_ids_before_spawning() {
+        for id in ["", "--help", "jNQXAC9IVRw&list=other", "日本語"] {
+            assert!(matches!(
+                open_in_browser(id),
+                Err(error) if error.kind() == io::ErrorKind::InvalidInput
+            ));
+        }
+    }
+
     #[test]
     fn publication_dates_prefer_exact_metadata_and_handle_utc_boundaries_and_invalid_dates() {
         for feed in [false, true] {