began new infrastructure

Yep, this is another one of my "famous" sweeping rewrites. Expect things to break.

Goals for this are:
- Greatly simplify node connections (particularly with arrays) so the code requires less maintenance/is more stable
- Redesign node structure to address issues where UI would stall for lengthy periods of time
- Less reliance on shared ptrs/greater reliance on QObject system for inheritance/memory management
- General code cleanup and improvements

app/node/graph.cpp

@@ -22,8 +22,7 @@
 
 namespace olive {
 
-NodeGraph::NodeGraph() :
-  operation_stack_(0)
+NodeGraph::NodeGraph()
 {
 }
 
@@ -35,133 +34,25 @@ void NodeGraph::Clear()
   node_children_.clear();
 }
 
-void NodeGraph::AddNode(Node *node)
+void NodeGraph::childEvent(QChildEvent *event)
 {
-  if (ContainsNode(node)) {
-    return;
-  }
+  Item::childEvent(event);
 
-  node->setParent(this);
+  Node* node = dynamic_cast<Node*>(event->child());
 
-  connect(node, &Node::EdgeAdded, this, &NodeGraph::SignalEdgeAdded);
-  connect(node, &Node::EdgeRemoved, this, &NodeGraph::SignalEdgeRemoved);
+  if (node) {
+    if (event->type() == QEvent::ChildAdded) {
 
-  node_children_.append(node);
+      node_children_.append(node);
+      emit NodeAdded(node);
 
-  emit NodeAdded(node);
-}
+    } else if (event->type() == QEvent::ChildRemoved) {
 
-void NodeGraph::BeginOperation()
-{
-  operation_stack_++;
-}
+      node_children_.removeOne(node);
+      emit NodeRemoved(node);
 
-void NodeGraph::EndOperation()
-{
-  operation_stack_--;
-
-  if (!operation_stack_) {
-    // Signal everything that we cached during the operation
-
-    // First, signal the removed edges
-    foreach (NodeEdgePtr e, cached_removed_edges_) {
-      emit EdgeRemoved(e);
     }
-    cached_removed_edges_.clear();
-
-    // Next, signal the removed nodes
-    foreach (Node* n, cached_removed_nodes_) {
-      emit NodeRemoved(n);
-    }
-    cached_removed_nodes_.clear();
-
-    // Next, signal the added nodes
-    foreach (Node* n, cached_added_nodes_) {
-      emit NodeAdded(n);
-    }
-    cached_added_nodes_.clear();
-
-    // Finally, signal the added edges
-    foreach (NodeEdgePtr e, cached_added_edges_) {
-      emit EdgeAdded(e);
-    }
-    cached_added_edges_.clear();
   }
 }
 
-void NodeGraph::SignalNodeAdded(Node* node)
-{
-  if (!operation_stack_) {
-    emit NodeAdded(node);
-  } else if (!cached_removed_nodes_.removeOne(node)) {
-    // If we already removed this node during the operation (appending a signal to
-    // cached_removed_nodes_), we just remove that instead of appending a new signal. However if we
-    // didn't (removeOne returning false), only then do we append an add signal
-    cached_added_nodes_.append(node);
-  }
-}
-
-void NodeGraph::SignalNodeRemoved(Node *node)
-{
-  if (!operation_stack_) {
-    emit NodeRemoved(node);
-  } else if (!cached_added_nodes_.removeOne(node)) {
-    // See SignalNodeAdded() for explanation of this
-    cached_removed_nodes_.append(node);
-  }
-}
-
-void NodeGraph::SignalEdgeAdded(NodeEdgePtr edge)
-{
-  if (!operation_stack_) {
-    emit EdgeAdded(edge);
-  } else if (!cached_removed_edges_.removeOne(edge)) {
-    // See SignalNodeAdded() for explanation of this
-    cached_added_edges_.append(edge);
-  }
-}
-
-void NodeGraph::SignalEdgeRemoved(NodeEdgePtr edge)
-{
-  if (!operation_stack_) {
-    emit EdgeRemoved(edge);
-  } else if (!cached_added_edges_.removeOne(edge)) {
-    // See SignalNodeAdded() for explanation of this
-    cached_removed_edges_.append(edge);
-  }
-}
-
-void NodeGraph::TakeNode(Node *node, QObject* new_parent)
-{
-  if (!ContainsNode(node)) {
-    return;
-  }
-
-  if (!node->CanBeDeleted()) {
-    qWarning() << "Tried to delete a Node that's been flagged as not deletable";
-    return;
-  }
-
-  node->DisconnectAll();
-
-  disconnect(node, &Node::EdgeAdded, this, &NodeGraph::EdgeAdded);
-  disconnect(node, &Node::EdgeRemoved, this, &NodeGraph::EdgeRemoved);
-
-  node->setParent(new_parent);
-
-  node_children_.removeAll(node);
-
-  emit NodeRemoved(node);
-}
-
-const QList<Node *> &NodeGraph::nodes() const
-{
-  return node_children_;
-}
-
-bool NodeGraph::ContainsNode(Node *n) const
-{
-  return (n->parent() == this);
-}
-
 }