feat: implement queue management system

- Add QueueManager in Rust backend with shuffle, repeat modes, and history
- Create queue Tauri commands (add, remove, next, previous, play_index, etc.)
- Wire Next/Previous buttons to backend queue
- Auto-advance to next track when current track ends
- Sync queue state with frontend QueuePanel
- Wire shuffle and repeat toggles to backend
- Add queue population when playing from album detail view

src-tauri/src/commands/mod.rs

@@ -4,8 +4,10 @@
 
 pub mod auth;
 pub mod playback;
+pub mod queue;
 pub mod search;
 
 pub use auth::*;
 pub use playback::*;
+pub use queue::*;
 pub use search::*;

src-tauri/src/commands/queue.rs

@@ -0,0 +1,122 @@
+//! Queue management Tauri commands
+
+use tauri::State;
+
+use crate::queue::{QueueState, QueueTrack, RepeatMode};
+use crate::AppState;
+
+/// Add a track to the queue
+#[tauri::command]
+pub fn add_to_queue(track: QueueTrack, state: State<'_, AppState>) -> Result<(), String> {
+    log::info!("Command: add_to_queue - {} by {}", track.title, track.artist);
+    state.queue.add_track(track);
+    Ok(())
+}
+
+/// Add multiple tracks to the queue
+#[tauri::command]
+pub fn add_tracks_to_queue(tracks: Vec<QueueTrack>, state: State<'_, AppState>) -> Result<(), String> {
+    log::info!("Command: add_tracks_to_queue - {} tracks", tracks.len());
+    state.queue.add_tracks(tracks);
+    Ok(())
+}
+
+/// Set the entire queue (replaces existing)
+#[tauri::command]
+pub fn set_queue(tracks: Vec<QueueTrack>, start_index: Option<usize>, state: State<'_, AppState>) -> Result<(), String> {
+    log::info!("Command: set_queue - {} tracks, start at {:?}", tracks.len(), start_index);
+    state.queue.set_queue(tracks, start_index);
+    Ok(())
+}
+
+/// Clear the queue
+#[tauri::command]
+pub fn clear_queue(state: State<'_, AppState>) -> Result<(), String> {
+    log::info!("Command: clear_queue");
+    state.queue.clear();
+    Ok(())
+}
+
+/// Remove a track from the queue by index
+#[tauri::command]
+pub fn remove_from_queue(index: usize, state: State<'_, AppState>) -> Result<Option<QueueTrack>, String> {
+    log::info!("Command: remove_from_queue - index {}", index);
+    Ok(state.queue.remove_track(index))
+}
+
+/// Get current track in queue
+#[tauri::command]
+pub fn get_current_queue_track(state: State<'_, AppState>) -> Result<Option<QueueTrack>, String> {
+    Ok(state.queue.current_track())
+}
+
+/// Get next track (for pre-loading/display)
+#[tauri::command]
+pub fn peek_next_track(state: State<'_, AppState>) -> Result<Option<QueueTrack>, String> {
+    Ok(state.queue.peek_next())
+}
+
+/// Advance to next track and return it
+#[tauri::command]
+pub fn next_track(state: State<'_, AppState>) -> Result<Option<QueueTrack>, String> {
+    log::info!("Command: next_track");
+    Ok(state.queue.next())
+}
+
+/// Go to previous track and return it
+#[tauri::command]
+pub fn previous_track(state: State<'_, AppState>) -> Result<Option<QueueTrack>, String> {
+    log::info!("Command: previous_track");
+    Ok(state.queue.previous())
+}
+
+/// Jump to a specific track by index
+#[tauri::command]
+pub fn play_queue_index(index: usize, state: State<'_, AppState>) -> Result<Option<QueueTrack>, String> {
+    log::info!("Command: play_queue_index - {}", index);
+    Ok(state.queue.play_index(index))
+}
+
+/// Set shuffle mode
+#[tauri::command]
+pub fn set_shuffle(enabled: bool, state: State<'_, AppState>) -> Result<(), String> {
+    log::info!("Command: set_shuffle - {}", enabled);
+    state.queue.set_shuffle(enabled);
+    Ok(())
+}
+
+/// Get shuffle status
+#[tauri::command]
+pub fn get_shuffle(state: State<'_, AppState>) -> Result<bool, String> {
+    Ok(state.queue.is_shuffle())
+}
+
+/// Set repeat mode
+#[tauri::command]
+pub fn set_repeat(mode: String, state: State<'_, AppState>) -> Result<(), String> {
+    log::info!("Command: set_repeat - {}", mode);
+    let repeat_mode = match mode.to_lowercase().as_str() {
+        "all" => RepeatMode::All,
+        "one" => RepeatMode::One,
+        _ => RepeatMode::Off,
+    };
+    state.queue.set_repeat(repeat_mode);
+    Ok(())
+}
+
+/// Get repeat mode
+#[tauri::command]
+pub fn get_repeat(state: State<'_, AppState>) -> Result<String, String> {
+    let mode = state.queue.get_repeat();
+    Ok(match mode {
+        RepeatMode::Off => "off".to_string(),
+        RepeatMode::All => "all".to_string(),
+        RepeatMode::One => "one".to_string(),
+    })
+}
+
+/// Get full queue state for frontend
+#[tauri::command]
+pub fn get_queue_state(state: State<'_, AppState>) -> Result<QueueState, String> {
+    Ok(state.queue.get_state())
+}

src-tauri/src/lib.rs

@@ -16,11 +16,13 @@ use tokio::sync::Mutex;
 use api::QobuzClient;
 use media_controls::{MediaControlsManager, TrackInfo};
 use player::Player;
+use queue::QueueManager;
 
 /// Application state shared across commands
 pub struct AppState {
     pub client: Arc<Mutex<QobuzClient>>,
     pub player: Player,
+    pub queue: QueueManager,
     pub media_controls: MediaControlsManager,
 }
 
@@ -29,6 +31,7 @@ impl AppState {
         Self {
             client: Arc::new(Mutex::new(QobuzClient::default())),
             player: Player::new(),
+            queue: QueueManager::new(),
             media_controls: MediaControlsManager::new(),
         }
     }
@@ -93,6 +96,22 @@ pub fn run() {
             commands::seek,
             commands::get_playback_state,
             commands::set_media_metadata,
+            // Queue commands
+            commands::add_to_queue,
+            commands::add_tracks_to_queue,
+            commands::set_queue,
+            commands::clear_queue,
+            commands::remove_from_queue,
+            commands::get_current_queue_track,
+            commands::peek_next_track,
+            commands::next_track,
+            commands::previous_track,
+            commands::play_queue_index,
+            commands::set_shuffle,
+            commands::get_shuffle,
+            commands::set_repeat,
+            commands::get_repeat,
+            commands::get_queue_state,
         ])
         .run(tauri::generate_context!())
         .expect("error while running tauri application");

src-tauri/src/queue/mod.rs

@@ -1,10 +1,476 @@
 //! Queue management module
 //!
 //! Handles playback queue with:
-//! - Queue manipulation (add, remove, reorder)
-//! - Shuffle modes
-//! - Repeat modes
-//! - Play history
+//! - Queue manipulation (add, remove, reorder, clear)
+//! - Current track tracking
+//! - Shuffle mode
+//! - Repeat modes (off, all, one)
+//! - Play history for going back
 
-// TODO: Implement queue management
-// pub mod manager;
+use std::collections::VecDeque;
+use std::sync::Mutex;
+
+/// Track info stored in the queue
+#[derive(Debug, Clone, serde::Serialize, serde::Deserialize)]
+pub struct QueueTrack {
+    pub id: u64,
+    pub title: String,
+    pub artist: String,
+    pub album: String,
+    pub duration_secs: u64,
+    pub artwork_url: Option<String>,
+}
+
+/// Repeat mode options
+#[derive(Debug, Clone, Copy, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
+pub enum RepeatMode {
+    Off,
+    All,
+    One,
+}
+
+impl Default for RepeatMode {
+    fn default() -> Self {
+        Self::Off
+    }
+}
+
+/// Queue state snapshot for frontend
+#[derive(Debug, Clone, serde::Serialize)]
+pub struct QueueState {
+    pub current_track: Option<QueueTrack>,
+    pub current_index: Option<usize>,
+    pub upcoming: Vec<QueueTrack>,
+    pub history: Vec<QueueTrack>,
+    pub shuffle: bool,
+    pub repeat: RepeatMode,
+    pub total_tracks: usize,
+}
+
+/// Queue manager for handling playback queue
+pub struct QueueManager {
+    /// All tracks in the queue (original order)
+    tracks: Mutex<Vec<QueueTrack>>,
+    /// Current playback index
+    current_index: Mutex<Option<usize>>,
+    /// Shuffle mode enabled
+    shuffle: Mutex<bool>,
+    /// Shuffled indices (when shuffle is on)
+    shuffle_order: Mutex<Vec<usize>>,
+    /// Position in shuffle order
+    shuffle_position: Mutex<usize>,
+    /// Repeat mode
+    repeat: Mutex<RepeatMode>,
+    /// History of played track indices (for going back)
+    history: Mutex<VecDeque<usize>>,
+}
+
+impl Default for QueueManager {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl QueueManager {
+    pub fn new() -> Self {
+        Self {
+            tracks: Mutex::new(Vec::new()),
+            current_index: Mutex::new(None),
+            shuffle: Mutex::new(false),
+            shuffle_order: Mutex::new(Vec::new()),
+            shuffle_position: Mutex::new(0),
+            repeat: Mutex::new(RepeatMode::Off),
+            history: Mutex::new(VecDeque::with_capacity(50)),
+        }
+    }
+
+    /// Add a track to the end of the queue
+    pub fn add_track(&self, track: QueueTrack) {
+        let mut tracks = self.tracks.lock().unwrap();
+        tracks.push(track);
+
+        // Update shuffle order if needed
+        if *self.shuffle.lock().unwrap() {
+            let mut order = self.shuffle_order.lock().unwrap();
+            order.push(tracks.len() - 1);
+        }
+    }
+
+    /// Add multiple tracks to the queue
+    pub fn add_tracks(&self, new_tracks: Vec<QueueTrack>) {
+        let mut tracks = self.tracks.lock().unwrap();
+        let start_idx = tracks.len();
+        tracks.extend(new_tracks);
+
+        // Update shuffle order if needed
+        if *self.shuffle.lock().unwrap() {
+            let mut order = self.shuffle_order.lock().unwrap();
+            for i in start_idx..tracks.len() {
+                order.push(i);
+            }
+        }
+    }
+
+    /// Set the entire queue (replaces existing)
+    pub fn set_queue(&self, new_tracks: Vec<QueueTrack>, start_index: Option<usize>) {
+        let mut tracks = self.tracks.lock().unwrap();
+        *tracks = new_tracks;
+
+        let mut current = self.current_index.lock().unwrap();
+        *current = start_index;
+
+        // Reset shuffle order
+        self.regenerate_shuffle_order();
+
+        // Clear history
+        self.history.lock().unwrap().clear();
+    }
+
+    /// Clear the queue
+    pub fn clear(&self) {
+        self.tracks.lock().unwrap().clear();
+        *self.current_index.lock().unwrap() = None;
+        self.shuffle_order.lock().unwrap().clear();
+        *self.shuffle_position.lock().unwrap() = 0;
+        self.history.lock().unwrap().clear();
+    }
+
+    /// Remove a track by index
+    pub fn remove_track(&self, index: usize) -> Option<QueueTrack> {
+        let mut tracks = self.tracks.lock().unwrap();
+        if index >= tracks.len() {
+            return None;
+        }
+
+        let removed = tracks.remove(index);
+
+        // Adjust current index if needed
+        let mut current = self.current_index.lock().unwrap();
+        if let Some(curr_idx) = *current {
+            if index < curr_idx {
+                *current = Some(curr_idx - 1);
+            } else if index == curr_idx {
+                // Currently playing track was removed
+                if curr_idx >= tracks.len() {
+                    *current = if tracks.is_empty() { None } else { Some(tracks.len() - 1) };
+                }
+            }
+        }
+
+        // Regenerate shuffle order
+        self.regenerate_shuffle_order();
+
+        Some(removed)
+    }
+
+    /// Get current track
+    pub fn current_track(&self) -> Option<QueueTrack> {
+        let tracks = self.tracks.lock().unwrap();
+        let current = self.current_index.lock().unwrap();
+
+        current.and_then(|idx| tracks.get(idx).cloned())
+    }
+
+    /// Get next track without advancing
+    pub fn peek_next(&self) -> Option<QueueTrack> {
+        let tracks = self.tracks.lock().unwrap();
+        if tracks.is_empty() {
+            return None;
+        }
+
+        let current = self.current_index.lock().unwrap();
+        let repeat = *self.repeat.lock().unwrap();
+        let shuffle = *self.shuffle.lock().unwrap();
+
+        // Handle repeat one - next is the same track
+        if repeat == RepeatMode::One {
+            return current.and_then(|idx| tracks.get(idx).cloned());
+        }
+
+        let next_idx = if shuffle {
+            let order = self.shuffle_order.lock().unwrap();
+            let pos = *self.shuffle_position.lock().unwrap();
+            let next_pos = pos + 1;
+
+            if next_pos < order.len() {
+                Some(order[next_pos])
+            } else if repeat == RepeatMode::All {
+                order.first().copied()
+            } else {
+                None
+            }
+        } else {
+            let curr_idx = current.unwrap_or(0);
+            let next_idx = curr_idx + 1;
+
+            if next_idx < tracks.len() {
+                Some(next_idx)
+            } else if repeat == RepeatMode::All {
+                Some(0)
+            } else {
+                None
+            }
+        };
+
+        next_idx.and_then(|idx| tracks.get(idx).cloned())
+    }
+
+    /// Advance to next track and return it
+    pub fn next(&self) -> Option<QueueTrack> {
+        let tracks = self.tracks.lock().unwrap();
+        if tracks.is_empty() {
+            return None;
+        }
+
+        let mut current = self.current_index.lock().unwrap();
+        let repeat = *self.repeat.lock().unwrap();
+        let shuffle = *self.shuffle.lock().unwrap();
+
+        // Save current to history before moving
+        if let Some(curr_idx) = *current {
+            let mut history = self.history.lock().unwrap();
+            history.push_back(curr_idx);
+            // Keep history limited
+            while history.len() > 50 {
+                history.pop_front();
+            }
+        }
+
+        // Handle repeat one
+        if repeat == RepeatMode::One {
+            return current.and_then(|idx| tracks.get(idx).cloned());
+        }
+
+        let next_idx = if shuffle {
+            let order = self.shuffle_order.lock().unwrap();
+            let mut pos = self.shuffle_position.lock().unwrap();
+            *pos += 1;
+
+            if *pos < order.len() {
+                Some(order[*pos])
+            } else if repeat == RepeatMode::All {
+                *pos = 0;
+                order.first().copied()
+            } else {
+                None
+            }
+        } else {
+            let curr_idx = current.unwrap_or(0);
+            let next_idx = curr_idx + 1;
+
+            if next_idx < tracks.len() {
+                Some(next_idx)
+            } else if repeat == RepeatMode::All {
+                Some(0)
+            } else {
+                None
+            }
+        };
+
+        *current = next_idx;
+        drop(current);
+        drop(tracks);
+
+        self.current_track()
+    }
+
+    /// Go to previous track and return it
+    pub fn previous(&self) -> Option<QueueTrack> {
+        let tracks = self.tracks.lock().unwrap();
+        if tracks.is_empty() {
+            return None;
+        }
+
+        let mut current = self.current_index.lock().unwrap();
+        let repeat = *self.repeat.lock().unwrap();
+        let shuffle = *self.shuffle.lock().unwrap();
+
+        // Try to get from history first
+        let mut history = self.history.lock().unwrap();
+        if let Some(prev_idx) = history.pop_back() {
+            *current = Some(prev_idx);
+
+            // Adjust shuffle position if needed
+            if shuffle {
+                let order = self.shuffle_order.lock().unwrap();
+                if let Some(pos) = order.iter().position(|&x| x == prev_idx) {
+                    *self.shuffle_position.lock().unwrap() = pos;
+                }
+            }
+
+            return tracks.get(prev_idx).cloned();
+        }
+        drop(history);
+
+        // No history, go to previous in order
+        let prev_idx = if shuffle {
+            let order = self.shuffle_order.lock().unwrap();
+            let mut pos = self.shuffle_position.lock().unwrap();
+
+            if *pos > 0 {
+                *pos -= 1;
+                Some(order[*pos])
+            } else if repeat == RepeatMode::All {
+                *pos = order.len().saturating_sub(1);
+                order.last().copied()
+            } else {
+                Some(order.first().copied().unwrap_or(0))
+            }
+        } else {
+            let curr_idx = current.unwrap_or(0);
+
+            if curr_idx > 0 {
+                Some(curr_idx - 1)
+            } else if repeat == RepeatMode::All {
+                Some(tracks.len().saturating_sub(1))
+            } else {
+                Some(0) // Stay at beginning
+            }
+        };
+
+        *current = prev_idx;
+        drop(current);
+        drop(tracks);
+
+        self.current_track()
+    }
+
+    /// Jump to a specific track by index
+    pub fn play_index(&self, index: usize) -> Option<QueueTrack> {
+        let tracks = self.tracks.lock().unwrap();
+        if index >= tracks.len() {
+            return None;
+        }
+
+        // Save current to history
+        let mut current = self.current_index.lock().unwrap();
+        if let Some(curr_idx) = *current {
+            let mut history = self.history.lock().unwrap();
+            history.push_back(curr_idx);
+            while history.len() > 50 {
+                history.pop_front();
+            }
+        }
+
+        *current = Some(index);
+
+        // Update shuffle position if needed
+        if *self.shuffle.lock().unwrap() {
+            let order = self.shuffle_order.lock().unwrap();
+            if let Some(pos) = order.iter().position(|&x| x == index) {
+                *self.shuffle_position.lock().unwrap() = pos;
+            }
+        }
+
+        tracks.get(index).cloned()
+    }
+
+    /// Toggle shuffle mode
+    pub fn set_shuffle(&self, enabled: bool) {
+        let mut shuffle = self.shuffle.lock().unwrap();
+        if *shuffle == enabled {
+            return;
+        }
+        *shuffle = enabled;
+        drop(shuffle);
+
+        if enabled {
+            self.regenerate_shuffle_order();
+        }
+    }
+
+    /// Get shuffle status
+    pub fn is_shuffle(&self) -> bool {
+        *self.shuffle.lock().unwrap()
+    }
+
+    /// Set repeat mode
+    pub fn set_repeat(&self, mode: RepeatMode) {
+        *self.repeat.lock().unwrap() = mode;
+    }
+
+    /// Get repeat mode
+    pub fn get_repeat(&self) -> RepeatMode {
+        *self.repeat.lock().unwrap()
+    }
+
+    /// Get queue state for frontend
+    pub fn get_state(&self) -> QueueState {
+        let tracks = self.tracks.lock().unwrap();
+        let current_index = *self.current_index.lock().unwrap();
+        let shuffle = *self.shuffle.lock().unwrap();
+        let repeat = *self.repeat.lock().unwrap();
+        let history = self.history.lock().unwrap();
+
+        let current_track = current_index.and_then(|idx| tracks.get(idx).cloned());
+
+        // Get upcoming tracks (after current)
+        let upcoming: Vec<QueueTrack> = if let Some(curr_idx) = current_index {
+            if shuffle {
+                let order = self.shuffle_order.lock().unwrap();
+                let pos = *self.shuffle_position.lock().unwrap();
+                order.iter()
+                    .skip(pos + 1)
+                    .take(20)
+                    .filter_map(|&idx| tracks.get(idx).cloned())
+                    .collect()
+            } else {
+                tracks.iter()
+                    .skip(curr_idx + 1)
+                    .take(20)
+                    .cloned()
+                    .collect()
+            }
+        } else {
+            tracks.iter().take(20).cloned().collect()
+        };
+
+        // Get history tracks (recent first)
+        let history_tracks: Vec<QueueTrack> = history.iter()
+            .rev()
+            .take(10)
+            .filter_map(|&idx| tracks.get(idx).cloned())
+            .collect();
+
+        QueueState {
+            current_track,
+            current_index,
+            upcoming,
+            history: history_tracks,
+            shuffle,
+            repeat,
+            total_tracks: tracks.len(),
+        }
+    }
+
+    /// Regenerate shuffle order
+    fn regenerate_shuffle_order(&self) {
+        let tracks = self.tracks.lock().unwrap();
+        let current_index = *self.current_index.lock().unwrap();
+
+        let mut order: Vec<usize> = (0..tracks.len()).collect();
+
+        // Fisher-Yates shuffle
+        use std::time::{SystemTime, UNIX_EPOCH};
+        let seed = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .unwrap_or_default()
+            .as_nanos() as usize;
+
+        for i in (1..order.len()).rev() {
+            let j = (seed.wrapping_mul(i + 1)) % (i + 1);
+            order.swap(i, j);
+        }
+
+        // If there's a current track, move it to the front
+        if let Some(curr_idx) = current_index {
+            if let Some(pos) = order.iter().position(|&x| x == curr_idx) {
+                order.remove(pos);
+                order.insert(0, curr_idx);
+            }
+        }
+
+        *self.shuffle_order.lock().unwrap() = order;
+        *self.shuffle_position.lock().unwrap() = 0;
+    }
+}

src/routes/+page.svelte

@@ -84,6 +84,26 @@
     duration: string;
   }
 
+  // Backend queue track format
+  interface BackendQueueTrack {
+    id: number;
+    title: string;
+    artist: string;
+    album: string;
+    duration_secs: number;
+    artwork_url: string | null;
+  }
+
+  interface BackendQueueState {
+    current_track: BackendQueueTrack | null;
+    current_index: number | null;
+    upcoming: BackendQueueTrack[];
+    history: BackendQueueTrack[];
+    shuffle: boolean;
+    repeat: 'Off' | 'All' | 'One';
+    total_tracks: number;
+  }
+
   interface PlayingTrack {
     id: number;
     title: string;
@@ -119,8 +139,9 @@
   let repeatMode = $state<'off' | 'all' | 'one'>('off');
   let isFavorite = $state(false);
 
-  // Queue State
+  // Queue State (synced from backend)
   let queue = $state<QueueTrack[]>([]);
+  let queueTotalTracks = $state(0);
 
   // Toast State
   let toast = $state<{ message: string; type: 'success' | 'error' | 'info' } | null>(null);
@@ -275,6 +296,32 @@
     duration = track.durationSeconds;
     currentTime = 0;
 
+    // Build queue from album tracks
+    if (selectedAlbum?.tracks) {
+      const trackIndex = selectedAlbum.tracks.findIndex(t => t.id === track.id);
+      const queueTracks: BackendQueueTrack[] = selectedAlbum.tracks.map(t => ({
+        id: t.id,
+        title: t.title,
+        artist: t.artist || selectedAlbum?.artist || 'Unknown Artist',
+        album: selectedAlbum?.title || '',
+        duration_secs: t.durationSeconds,
+        artwork_url: artwork || null
+      }));
+
+      // Set the queue starting at the clicked track
+      try {
+        await invoke('set_queue', {
+          tracks: queueTracks,
+          startIndex: trackIndex >= 0 ? trackIndex : 0
+        });
+        console.log(`Queue set with ${queueTracks.length} tracks, starting at index ${trackIndex}`);
+        // Sync queue state to update UI
+        await syncQueueState();
+      } catch (err) {
+        console.error('Failed to set queue:', err);
+      }
+    }
+
     // Try to play the track
     try {
       console.log('Invoking play_track with trackId:', track.id);
@@ -321,18 +368,27 @@
     invoke('set_volume', { volume: newVolume / 100 }).catch(console.error);
   }
 
-  function toggleShuffle() {
+  async function toggleShuffle() {
     isShuffle = !isShuffle;
-    showToast(isShuffle ? 'Shuffle enabled' : 'Shuffle disabled', 'info');
+    try {
+      await invoke('set_shuffle', { enabled: isShuffle });
+      showToast(isShuffle ? 'Shuffle enabled' : 'Shuffle disabled', 'info');
+    } catch (err) {
+      console.error('Failed to set shuffle:', err);
+      isShuffle = !isShuffle; // Revert
+    }
   }
 
-  function toggleRepeat() {
-    if (repeatMode === 'off') repeatMode = 'all';
-    else if (repeatMode === 'all') repeatMode = 'one';
-    else repeatMode = 'off';
-
-    const messages = { off: 'Repeat off', all: 'Repeat all', one: 'Repeat one' };
-    showToast(messages[repeatMode], 'info');
+  async function toggleRepeat() {
+    const nextMode = repeatMode === 'off' ? 'all' : repeatMode === 'all' ? 'one' : 'off';
+    try {
+      await invoke('set_repeat', { mode: nextMode });
+      repeatMode = nextMode;
+      const messages = { off: 'Repeat off', all: 'Repeat all', one: 'Repeat one' };
+      showToast(messages[repeatMode], 'info');
+    } catch (err) {
+      console.error('Failed to set repeat:', err);
+    }
   }
 
   function toggleFavorite() {
@@ -340,23 +396,149 @@
     showToast(isFavorite ? 'Added to favorites' : 'Removed from favorites', 'success');
   }
 
-  // Skip track handlers (will be wired to queue when implemented)
-  function handleSkipBack() {
+  // Skip track handlers - wired to backend queue
+  async function handleSkipBack() {
     if (!currentTrack) return;
     // If more than 3 seconds in, restart track; otherwise go to previous
     if (currentTime > 3) {
       handleSeek(0);
-      showToast('Restarted track', 'info');
-    } else {
-      // TODO: Go to previous track in queue
-      showToast('Previous track (not implemented yet)', 'info');
+      return;
+    }
+
+    try {
+      const prevTrack = await invoke<BackendQueueTrack | null>('previous_track');
+      if (prevTrack) {
+        await playQueueTrack(prevTrack);
+      } else {
+        // No previous track, just restart
+        handleSeek(0);
+      }
+    } catch (err) {
+      console.error('Failed to go to previous track:', err);
+      showToast('Failed to go to previous track', 'error');
     }
   }
 
-  function handleSkipForward() {
+  async function handleSkipForward() {
     if (!currentTrack) return;
-    // TODO: Go to next track in queue
-    showToast('Next track (not implemented yet)', 'info');
+
+    try {
+      const nextTrackResult = await invoke<BackendQueueTrack | null>('next_track');
+      if (nextTrackResult) {
+        await playQueueTrack(nextTrackResult);
+      } else {
+        // No next track - stop playback
+        await invoke('stop_playback');
+        isPlaying = false;
+        showToast('Queue ended', 'info');
+      }
+    } catch (err) {
+      console.error('Failed to go to next track:', err);
+      showToast('Failed to go to next track', 'error');
+    }
+  }
+
+  // Helper to play a track from the queue
+  async function playQueueTrack(track: BackendQueueTrack) {
+    currentTrack = {
+      id: track.id,
+      title: track.title,
+      artist: track.artist,
+      album: track.album,
+      artwork: track.artwork_url || '',
+      duration: track.duration_secs,
+      quality: 'Hi-Res' // Will be updated by actual quality info
+    };
+
+    duration = track.duration_secs;
+    currentTime = 0;
+
+    try {
+      await invoke('play_track', { trackId: track.id });
+      isPlaying = true;
+
+      // Update MPRIS
+      await invoke('set_media_metadata', {
+        title: track.title,
+        artist: track.artist,
+        album: track.album,
+        durationSecs: track.duration_secs,
+        coverUrl: track.artwork_url
+      });
+
+      // Refresh queue state
+      await syncQueueState();
+    } catch (err) {
+      console.error('Failed to play queue track:', err);
+      showToast(`Playback error: ${err}`, 'error');
+      isPlaying = false;
+    }
+  }
+
+  // Sync queue state from backend
+  async function syncQueueState() {
+    try {
+      const queueState = await invoke<BackendQueueState>('get_queue_state');
+
+      // Convert backend queue tracks to frontend format
+      queue = queueState.upcoming.map(t => ({
+        id: String(t.id),
+        artwork: t.artwork_url || '',
+        title: t.title,
+        artist: t.artist,
+        duration: formatDuration(t.duration_secs)
+      }));
+
+      queueTotalTracks = queueState.total_tracks;
+      isShuffle = queueState.shuffle;
+      repeatMode = queueState.repeat.toLowerCase() as 'off' | 'all' | 'one';
+    } catch (err) {
+      console.error('Failed to sync queue state:', err);
+    }
+  }
+
+  // Play a specific track from the queue panel
+  async function handleQueueTrackPlay(trackId: string) {
+    try {
+      // Find the index in the queue
+      const queueState = await invoke<BackendQueueState>('get_queue_state');
+      const allTracks = [queueState.current_track, ...queueState.upcoming].filter(Boolean) as BackendQueueTrack[];
+      const trackIndex = allTracks.findIndex(t => String(t.id) === trackId);
+
+      if (trackIndex >= 0) {
+        // If it's the current track (index 0), just ensure it's playing
+        if (trackIndex === 0 && queueState.current_index !== null) {
+          // Already current, nothing to do
+          return;
+        }
+
+        // Play by index (accounting for current track offset)
+        const actualIndex = queueState.current_index !== null
+          ? queueState.current_index + trackIndex
+          : trackIndex;
+
+        const track = await invoke<BackendQueueTrack | null>('play_queue_index', { index: actualIndex });
+        if (track) {
+          await playQueueTrack(track);
+        }
+      }
+    } catch (err) {
+      console.error('Failed to play queue track:', err);
+      showToast('Failed to play track', 'error');
+    }
+  }
+
+  // Clear the queue
+  async function handleClearQueue() {
+    try {
+      await invoke('clear_queue');
+      queue = [];
+      queueTotalTracks = 0;
+      showToast('Queue cleared', 'info');
+    } catch (err) {
+      console.error('Failed to clear queue:', err);
+      showToast('Failed to clear queue', 'error');
+    }
   }
 
   // Toast Functions
@@ -440,6 +622,8 @@
 
   let pollInterval: ReturnType<typeof setInterval> | null = null;
 
+  let isAdvancingTrack = false; // Prevent multiple advances
+
   async function pollPlaybackState() {
     if (!currentTrack) return;
 
@@ -451,10 +635,24 @@
         currentTime = state.position;
         isPlaying = state.is_playing;
 
-        // Check if track ended
-        if (state.duration > 0 && state.position >= state.duration && !state.is_playing) {
-          // Track finished - could trigger next track here
-          console.log('Track finished playing');
+        // Check if track ended - auto-advance to next
+        if (state.duration > 0 && state.position >= state.duration - 1 && !state.is_playing && !isAdvancingTrack) {
+          console.log('Track finished, advancing to next...');
+          isAdvancingTrack = true;
+
+          try {
+            const nextTrackResult = await invoke<BackendQueueTrack | null>('next_track');
+            if (nextTrackResult) {
+              await playQueueTrack(nextTrackResult);
+            } else {
+              // Queue ended
+              console.log('Queue ended');
+            }
+          } catch (err) {
+            console.error('Failed to auto-advance:', err);
+          } finally {
+            isAdvancingTrack = false;
+          }
         }
       }
     } catch (err) {
@@ -483,6 +681,13 @@
     return () => document.removeEventListener('keydown', handleKeydown);
   });
 
+  // Sync queue state when opening queue panel
+  $effect(() => {
+    if (isQueueOpen) {
+      syncQueueState();
+    }
+  });
+
   // Derived values for NowPlayingBar
   const currentQueueTrack = $derived<QueueTrack | null>(currentTrack ? {
     id: String(currentTrack.id),
@@ -572,11 +777,9 @@
       onClose={() => (isQueueOpen = false)}
       currentTrack={currentQueueTrack ?? undefined}
       upcomingTracks={queue}
-      onClearQueue={() => {
-        queue = [];
-        showToast('Queue cleared', 'info');
-      }}
-      onSaveAsPlaylist={() => showToast('Saved as playlist', 'success')}
+      onPlayTrack={handleQueueTrackPlay}
+      onClearQueue={handleClearQueue}
+      onSaveAsPlaylist={() => showToast('Save as playlist coming soon', 'info')}
     />
 
     <!-- Full Screen Now Playing -->