fix(remote playback): Move audio between remote players

src-tauri/src/playback_mode/mod.rs

@@ -215,8 +215,16 @@ impl PlaybackModeManager {
         log::info!("[PlaybackMode] transfer_to_remote_inner ENTERED");
         debug!("[PlaybackMode] transfer_to_remote_inner: session_id={}", session_id);
 
+        // If we're already controlling a remote session, that *old* session — not
+        // the idle local player — is the source of truth for the current track and
+        // position. Capture it so we can resume there and stop it afterwards.
+        let previous_remote_session = match self.get_mode() {
+            PlaybackMode::Remote { session_id: prev } if prev != session_id => Some(prev),
+            _ => None,
+        };
+
         // Get current player state and queue context
-        let (queue_ids, current_index, position_seconds, queue_context) = {
+        let (queue_ids, mut current_index, mut position_seconds, queue_context) = {
             log::info!("[PlaybackMode] Acquiring player controller lock...");
             debug!("[PlaybackMode] Acquiring player controller lock...");
             let player = self.player_controller.lock().await;
@@ -313,6 +321,46 @@ impl PlaybackModeManager {
             }
         };
 
+        // Remote -> remote switch: take the current track and position from the
+        // session we're leaving, since the local player is idle and reports 0.
+        if let Some(ref prev_session_id) = previous_remote_session {
+            log::info!(
+                "[PlaybackMode] Remote->remote switch; reading state from previous session {}",
+                prev_session_id
+            );
+            match client.get_session(prev_session_id).await {
+                Ok(Some(session)) => {
+                    // Resume at the previous session's position.
+                    if let Some(ticks) = session.play_state.as_ref().and_then(|ps| ps.position_ticks) {
+                        position_seconds = ticks as f64 / TICKS_PER_SECOND;
+                        log::info!(
+                            "[PlaybackMode] Using previous remote position: {:.2}s",
+                            position_seconds
+                        );
+                    }
+                    // Resume on whichever track the previous session reached.
+                    if let Some(now_id) = session.now_playing_item.as_ref().and_then(|i| i.id.as_deref()) {
+                        if let Some(idx) = queue_ids.iter().position(|id| id == now_id) {
+                            log::info!(
+                                "[PlaybackMode] Previous session is on track {} (queue index {})",
+                                now_id,
+                                idx
+                            );
+                            current_index = idx;
+                        } else {
+                            log::warn!(
+                                "[PlaybackMode] Previous session's track {} not found in queue; keeping index {}",
+                                now_id,
+                                current_index
+                            );
+                        }
+                    }
+                }
+                Ok(None) => log::warn!("[PlaybackMode] Previous remote session not found while reading state"),
+                Err(e) => log::warn!("[PlaybackMode] Failed to read previous remote session: {}", e),
+            }
+        }
+
         // Calculate position in ticks (from the live position read above)
         let start_position_ticks = start_position_ticks_from_seconds(position_seconds);
 
@@ -446,6 +494,16 @@ impl PlaybackModeManager {
             }
         }
 
+        // Remote -> remote switch: stop the session we just left so we don't end
+        // up with two devices playing at once. Do this only after the new session
+        // is confirmed playing, so a failure here doesn't leave us with silence.
+        if let Some(prev_session_id) = previous_remote_session {
+            log::info!("[PlaybackMode] Stopping previous remote session {}", prev_session_id);
+            if let Err(e) = client.send_session_command(prev_session_id, "Stop").await {
+                log::warn!("[PlaybackMode] Failed to stop previous remote session: {}", e);
+            }
+        }
+
         // Stop local playback (queue should remain intact for remote session)
         log::info!("[PlaybackMode] Stopping local playback - queue should NOT be cleared");
         {