feat(music): progress/seek bar in popup

Resolves #128.

src/clients/music/mod.rs

@@ -9,9 +9,17 @@ pub mod mpd;
 #[cfg(feature = "music+mpris")]
 pub mod mpris;
 
+pub const TICK_INTERVAL_MS: u64 = 200;
+
 #[derive(Clone, Debug)]
 pub enum PlayerUpdate {
+    /// Triggered when the track or player state notably changes,
+    /// such as a new track playing, the player being paused, or a volume change.
     Update(Box<Option<Track>>, Status),
+    /// Triggered at regular intervals while a track is playing.
+    /// Used to keep track of the progress through the current track.
+    ProgressTick(ProgressTick),
+    /// Triggered when the client disconnects from the player.
     Disconnect,
 }
 
@@ -27,23 +35,27 @@ pub struct Track {
     pub cover_path: Option<String>,
 }
 
-#[derive(Clone, Debug)]
+#[derive(Clone, Copy, Debug)]
 pub enum PlayerState {
     Playing,
     Paused,
     Stopped,
 }
 
-#[derive(Clone, Debug)]
+#[derive(Clone, Copy, Debug)]
 pub struct Status {
     pub state: PlayerState,
-    pub volume_percent: u8,
-    pub duration: Option<Duration>,
-    pub elapsed: Option<Duration>,
+    pub volume_percent: Option<u8>,
     pub playlist_position: u32,
     pub playlist_length: u32,
 }
 
+#[derive(Clone, Copy, Debug)]
+pub struct ProgressTick {
+    pub duration: Option<Duration>,
+    pub elapsed: Option<Duration>,
+}
+
 pub trait MusicClient {
     fn play(&self) -> Result<()>;
     fn pause(&self) -> Result<()>;
@@ -51,6 +63,7 @@ pub trait MusicClient {
     fn prev(&self) -> Result<()>;
 
     fn set_volume_percent(&self, vol: u8) -> Result<()>;
+    fn seek(&self, duration: Duration) -> Result<()>;
 
     fn subscribe_change(&self) -> broadcast::Receiver<PlayerUpdate>;
 }