Synchronize AutoDJ next deck with top track in queue

src/library/autodj/autodjprocessor.cpp

@@ -534,6 +534,10 @@ AutoDJProcessor::AutoDJError AutoDJProcessor::toggleAutoDJ(bool enable) {
                 &DeckAttributes::rateChanged,
                 this,
                 &AutoDJProcessor::playerRateChanged);
+        connect(m_pAutoDJTableModel,
+                &PlaylistTableModel::firstTrackChanged,
+                this,
+                &AutoDJProcessor::playlistFirstTrackChanged);
 
         if (!leftDeckPlaying && !rightDeckPlaying) {
             // Both decks are stopped. Load a track into deck 1 and start it
@@ -1665,6 +1669,22 @@ void AutoDJProcessor::playerRateChanged(DeckAttributes* pAttributes) {
     calculateTransition(fromDeck, getOtherDeck(fromDeck), false);
 }
 
+void AutoDJProcessor::playlistFirstTrackChanged() {
+    if constexpr (sDebug) {
+        qDebug() << this << "playlistFirstTrackChanged";
+    }
+    if (m_eState != ADJ_DISABLED) {
+        DeckAttributes* pLeftDeck = getLeftDeck();
+        DeckAttributes* pRightDeck = getRightDeck();
+
+        if (!pLeftDeck->isPlaying()) {
+            loadNextTrackFromQueue(*pLeftDeck);
+        } else if (!pRightDeck->isPlaying()) {
+            loadNextTrackFromQueue(*pRightDeck);
+        }
+    }
+}
+
 void AutoDJProcessor::setTransitionTime(int time) {
     if constexpr (sDebug) {
         qDebug() << this << "setTransitionTime" << time;

src/library/autodj/autodjprocessor.h

@@ -219,6 +219,7 @@ class AutoDJProcessor : public QObject {
     void playerLoadingTrack(DeckAttributes* pDeck, TrackPointer pNewTrack, TrackPointer pOldTrack);
     void playerEmpty(DeckAttributes* pDeck);
     void playerRateChanged(DeckAttributes* pDeck);
+    void playlistFirstTrackChanged();
 
     void controlEnableChangeRequest(double value);
     void controlFadeNow(double value);

src/library/playlisttablemodel.cpp

@@ -250,6 +250,10 @@ void PlaylistTableModel::removeTracks(const QModelIndexList& indices) {
     m_pTrackCollectionManager->internalCollection()->getPlaylistDAO().removeTracksFromPlaylist(
             m_iPlaylistId,
             std::move(trackPositions));
+
+    if (trackPositions.contains(1)) {
+        emit firstTrackChanged();
+    }
 }
 
 void PlaylistTableModel::moveTrack(const QModelIndex& sourceIndex,
@@ -275,6 +279,10 @@ void PlaylistTableModel::moveTrack(const QModelIndex& sourceIndex,
     }
 
     m_pTrackCollectionManager->internalCollection()->getPlaylistDAO().moveTrack(m_iPlaylistId, oldPosition, newPosition);
+
+    if (oldPosition == 1 || newPosition == 1) {
+        emit firstTrackChanged();
+    }
 }
 
 bool PlaylistTableModel::isLocked() {

src/library/playlisttablemodel.h

@@ -38,6 +38,9 @@ class PlaylistTableModel final : public TrackSetTableModel {
   private slots:
     void playlistsChanged(const QSet<int>& playlistIds);
 
+  signals:
+    void firstTrackChanged();
+
   private:
     void initSortColumnMapping() override;