Ensure mix parenting is updated in case of clip cut

src/timeline2/model/timelinefunctions.cpp

@@ -128,6 +128,7 @@ bool TimelineFunctions::processClipCut(const std::shared_ptr<TimelineItemModel>
         return false;
     }
     PlaylistState::ClipState state = timeline->m_allClips[clipId]->clipState();
+    // Check if clip has an end Mix
     bool res = cloneClip(timeline, clipId, newId, state, undo, redo);
     timeline->m_blockRefresh = true;
     res = res && timeline->requestItemResize(clipId, position - start, true, true, undo, redo);
@@ -141,6 +142,18 @@ bool TimelineFunctions::processClipCut(const std::shared_ptr<TimelineItemModel>
     // The next requestclipmove does not check for duration change since we don't invalidate timeline, so check duration change now
     bool durationChanged = trackDuration != timeline->getTrackById_const(trackId)->trackDuration();
     res = res && timeline->requestClipMove(newId, trackId, position, true, true, false, true, undo, redo);
+    
+    if (timeline->getTrackById_const(trackId)->hasEndMix(clipId)) {
+        Fun local_undo = [timeline, trackId, clipId, newId]() { 
+            timeline->getTrackById_const(trackId)->reAssignEndMix(newId, clipId);
+            return true; };
+        Fun local_redo = [timeline, trackId, clipId, newId]() {
+            timeline->getTrackById_const(trackId)->reAssignEndMix(clipId, newId);
+            return true; };
+        local_redo();
+        UPDATE_UNDO_REDO_NOLOCK(local_redo, local_undo, undo, redo);
+    }
+    
     if (durationChanged) {
         // Track length changed, check project duration
         Fun updateDuration = [timeline]() {

src/timeline2/model/trackmodel.cpp

@@ -2168,3 +2168,12 @@ const std::shared_ptr<AssetParameterModel> TrackModel::mixModel(int cid)
     }
     return nullptr;
 }
+
+bool TrackModel::reAssignEndMix(int currentId, int newId)
+{
+    Q_ASSERT(m_mixList.contains(currentId));
+    int mixedClip = m_mixList.value(currentId);
+    m_mixList.remove(currentId);
+    m_mixList.insert(newId, mixedClip);
+    return true;
+}

src/timeline2/model/trackmodel.hpp

@@ -132,6 +132,9 @@ public:
     bool createMix(std::pair<int, int> clipIds, std::pair<int, int> mixData);
     /** @brief Create a mix composition using mix info */
     bool createMix(MixInfo info, bool isAudio);
+    /** @brief Change id of first clip in a mix (in case of clip cut) */
+    bool reAssignEndMix(int currentId, int newId);
+    /** @brief Ensure we don't have unsynced mixes in the playlist (mixes without owner clip) */
     void syncronizeMixes(bool finalMove);
     /** @brief Switch a clip from one playlist to the other */
     bool switchPlaylist(int clipId, int position, int sourcePlaylist, int destPlaylist);