Fix end-of-track handoff by sending NEXT action

src/qconnect.rs

@@ -367,6 +367,18 @@ fn quality_to_format_id(quality: u32) -> u32 {
     }
 }
 
+/// RNDR_SRVR_RENDERER_ACTION (24): renderer reports a local user action.
+/// ActionType: 0=UNKNOWN, 1=PREVIOUS, 2=NEXT, 3=REPEAT_OFF, 4=REPEAT_ONE, 5=REPEAT_ALL,
+///             6=SHUFFLE_OFF, 7=SHUFFLE_ON, 8=SEEK
+fn msg_renderer_action(action: u64, seek_position: Option<u32>) -> Vec<u8> {
+    let mut payload = Vec::new();
+    if let Some(pos) = seek_position {
+        payload.extend(encode_field_varint(1, pos as u64)); // field 1: seek_position
+    }
+    payload.extend(encode_field_varint(2, action)); // field 2: action
+    build_qconnect_message(24, &payload)
+}
+
 /// RNDR_SRVR_VOLUME_CHANGED (25): renderer reports volume.
 fn msg_volume_changed(volume: u64) -> Vec<u8> {
     let payload = encode_field_varint(1, volume);
@@ -882,14 +894,19 @@ async fn run_connection(
                         && has_seen_position_progress
                         && elapsed_since_play > std::time::Duration::from_secs(3)
                     {
-                        // Track ended naturally — keep reporting PLAYING with position=duration
-                        // so the server detects end-of-track and sends next track via SET_STATE
                         if !track_ended {
-                            info!("[TICK] Track ended naturally, reporting position=duration ({}ms)", current_duration_ms);
+                            // Track ended naturally — send final position then request next track
+                            info!("[TICK] Track ended naturally, sending ACTION_TYPE_NEXT");
                             track_ended = true;
                             current_position_ms = current_duration_ms;
+                            send_state!(ws_tx, msg_id);
+
+                            // Tell server to advance to next track (ACTION_TYPE_NEXT = 2)
+                            let action_msg = msg_renderer_action(2, None);
+                            ws_tx.send(Message::Binary(build_payload_frame(msg_id, &action_msg).into())).await?;
+                            msg_id += 1;
                         }
-                        send_state!(ws_tx, msg_id);
+                        // Don't spam — wait for server to send new SET_STATE
                     } else if status.state == PlayerState::Stopped {
                         debug!("[TICK] Player stopped but grace period (elapsed={:?}, progress={}), ignoring",
                             elapsed_since_play, has_seen_position_progress);