Fix bug where undoing+redoing AddWire multiple times crashes

CircuitBuffer.cpp

@@ -35,8 +35,8 @@ void CircuitBuffer::addFromScene(const QList<Part*> &parts, const QList<Wire*>&
     }
     for(auto wire : wires)
     {
-        auto wireInputPart = (Part*)wire->m_connectorInput->parentItem();
-        auto wireOutputPart = (Part*)wire->m_connectorOutput->parentItem();
+        auto wireInputPart = wire->m_connectorInput->parentPart();
+        auto wireOutputPart = wire->m_connectorOutput->parentPart();
 
         // Create wireData
         WireData wireData;

Connector.cpp

@@ -17,6 +17,11 @@ Connector::Connector(Scene* scene, Part *parentPart, ConnectorType::ConnectorTyp
     setFlag(QGraphicsItem::ItemSendsScenePositionChanges);
 }
 
+Part* Connector::parentPart()
+{
+    return (Part*)parentItem();
+}
+
 QRectF Connector::boundingRect() const
 {
     if(m_connectorType == ConnectorType::Output)

Connector.h

@@ -9,7 +9,7 @@ class Part;
 class Wire;
 class Scene;
 
-class Connector : public QGraphicsItem
+class Connector : private QGraphicsItem
 {
 public:
     friend class Scene;
@@ -24,6 +24,8 @@ public:
 
     Connector(Scene* scene, Part *parentPart, ConnectorType::ConnectorType side);
 
+    Part* parentPart();
+
     QRectF boundingRect() const override; // For drawing
     QPainterPath shape() const override; // For selection ("Hitbox")
     void paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget) override;

FileHandler.cpp

@@ -52,8 +52,8 @@ bool FileHandler::save(QString filename)
     fOut << "[wires]\n";
     for(auto wire : m_logic->m_wires)
     {
-        auto wireInputPart = (Part*)wire->m_connectorInput->parentItem();
-        auto wireOutputPart = (Part*)wire->m_connectorOutput->parentItem();
+        auto wireInputPart = wire->m_connectorInput->parentPart();
+        auto wireOutputPart = wire->m_connectorOutput->parentPart();
 
         fOut << wireInputPart << " " << wireInputPart->m_outputs.indexOf(wire->m_connectorInput) << " " << wireOutputPart << " " << wireOutputPart->m_inputs.indexOf(wire->m_connectorOutput) << "\n";
     }

Part.cpp

@@ -34,6 +34,16 @@ PartType::PartType Part::partType()
     return m_partType;
 }
 
+QPointF Part::getPos() const
+{
+    return pos();
+}
+
+void Part::setPos(QPointF pos)
+{
+    QGraphicsItem::setPos(pos);
+}
+
 void Part::addInputs(int amount)
 {
     for(int i = 0; i < amount; i++)

Part.h

@@ -9,7 +9,7 @@
 class Connector;
 class Logic;
 
-class Part : public QGraphicsItem
+class Part : protected QGraphicsItem
 {
 public:
     friend class Connector;
@@ -17,6 +17,7 @@ public:
     friend class Logic;
     friend class AddPart;
     friend class RemoveParts;
+    friend class AddWire;
     friend class RemoveWire;
     friend class CopyParts;
 
@@ -45,6 +46,9 @@ public:
 
     PartType::PartType partType();
 
+    QPointF getPos() const;
+    void setPos(QPointF pos);
+
     void addInputs(int amount);
     void addOutputs(int amount);
 

Wire.h

@@ -6,7 +6,7 @@
 class Connector;
 class Scene;
 
-class Wire : public QGraphicsLineItem
+class Wire : private QGraphicsLineItem
 {
 public:
     friend class Connector;