nodes: link edges to IDs rather than objects

Allows code to know whether the connected parameters has been removed or
not.

app/node/output/track/track.cpp

@@ -55,6 +55,11 @@ TrackOutput::TrackOutput() :
   track_height_ = kTrackHeightDefault;
 }
 
+TrackOutput::~TrackOutput()
+{
+  DisconnectAll();
+}
+
 void TrackOutput::set_track_type(const Timeline::TrackType &track_type)
 {
   track_type_ = track_type;
@@ -553,7 +558,7 @@ void TrackOutput::BlockConnected(NodeEdgePtr edge)
 
 void TrackOutput::BlockDisconnected(NodeEdgePtr edge)
 {
-  Block* b = static_cast<Block*>(edge->output()->parentNode());
+  Block* b = static_cast<Block*>(edge->output_node());
 
   if (block_cache_.contains(b)) {
     block_cache_.removeOne(b);

app/node/output/track/track.h

@@ -36,6 +36,8 @@ class TrackOutput : public Node
 public:
   TrackOutput();
 
+  virtual ~TrackOutput() override;
+
   const Timeline::TrackType& track_type() const;
   void set_track_type(const Timeline::TrackType& track_type);
 

app/node/output/track/tracklist.cpp

@@ -134,7 +134,7 @@ TrackOutput* TrackList::AddTrack()
   return track;
 }
 
-void TrackList::RemoveTrack()
+void TrackList::RemoveTrack(QObject* new_parent)
 {
   if (track_cache_.isEmpty()) {
     return;
@@ -144,7 +144,11 @@ void TrackList::RemoveTrack()
 
   GetParentGraph()->TakeNode(track);
 
-  delete track;
+  if (!new_parent) {
+    delete track;
+  } else {
+    track->setParent(new_parent);
+  }
 
   track_input_->RemoveLast();
 }

app/node/output/track/tracklist.h

@@ -44,7 +44,7 @@ public:
 
   TrackOutput *AddTrack();
 
-  void RemoveTrack();
+  void RemoveTrack(QObject *new_parent);
 
   const rational& GetTotalLength() const;
 

app/node/output/viewer/viewer.cpp

@@ -62,6 +62,11 @@ ViewerOutput::ViewerOutput() :
   uuid_ = QUuid::createUuid();
 }
 
+ViewerOutput::~ViewerOutput()
+{
+  DisconnectAll();
+}
+
 Node *ViewerOutput::copy() const
 {
   return new ViewerOutput();

app/node/output/viewer/viewer.h

@@ -47,6 +47,8 @@ class ViewerOutput : public Node
 public:
   ViewerOutput();
 
+  virtual ~ViewerOutput() override;
+
   virtual Node* copy() const override;
 
   virtual QString Name() const override;