Restore undo/redo

Signed-off-by: carlitosan <82187351+carlitosan@users.noreply.github.com>

Gems/ScriptCanvas/Code/Editor/Assets/ScriptCanvasUndoHelper.h

@@ -8,22 +8,27 @@
 
 #pragma once
 #include <ScriptCanvas/Bus/UndoBus.h>
+#include <Editor/Undo/ScriptCanvasUndoManager.h>
 
 namespace ScriptCanvasEditor
 {
-    class ScriptCanvasMemoryAsset;
 
     // Helper class that provides the implementation for UndoRequestBus
-    class UndoHelper : UndoRequestBus::Handler
+    class UndoHelper
+        : public UndoRequestBus::Handler
+        , public AzToolsFramework::UndoSystem::IUndoNotify
     {
     public:
 
-        UndoHelper(ScriptCanvasMemoryAsset& memoryAsset);
+        UndoHelper();
+        UndoHelper(SourceHandle source);
         ~UndoHelper();
 
         UndoCache* GetSceneUndoCache()  override;
         UndoData CreateUndoData() override;
 
+        void SetSource(SourceHandle source);
+
         void BeginUndoBatch(AZStd::string_view label) override;
         void EndUndoBatch() override;
         void AddUndo(AzToolsFramework::UndoSystem::URSequencePoint* seqPoint) override;
@@ -41,6 +46,7 @@ namespace ScriptCanvasEditor
         bool CanRedo() const override;
 
     private:
+        void OnUndoStackChanged() override;
 
         void UpdateCache();
 
@@ -51,7 +57,7 @@ namespace ScriptCanvasEditor
         };
 
         Status m_status = Status::Idle;
-
-        ScriptCanvasMemoryAsset& m_memoryAsset;
+        SceneUndoState m_undoState;
+        SourceHandle m_memoryAsset;
     };
 }