ObjectMetaData.h

#pragma once
 
#include <Foundation/Communication/Event.h>
#include <Foundation/Containers/HashTable.h>
#include <Foundation/Reflection/ReflectionUtils.h>
#include <Foundation/Serialization/AbstractObjectGraph.h>
#include <Foundation/Types/RefCounted.h>
#include <Foundation/Types/SharedPtr.h>
#include <ToolsFoundation/ToolsFoundationDLL.h>
 
template <typename KEY, typename VALUE>
class plObjectMetaData
{
 
public:
  struct EventData
  {
    KEY m_ObjectKey;
    const VALUE* m_pValue;
    plUInt32 m_uiModifiedFlags;
  };
 
  plEvent<const EventData&> m_DataModifiedEvent;
 
  // \brief Storage for the meta data so it can be swapped when using multiple sub documents.
  class Storage : public plRefCounted
  {
  public:
    mutable enum class AccessMode { Nothing,
      Read,
      Write } m_AccessMode;
    mutable KEY m_AcessingKey;
    mutable plMutex m_Mutex;
    plHashTable<KEY, VALUE> m_MetaData;
 
    plEvent<const EventData&> m_DataModifiedEvent;
  };
 
  using plMetaStorageType = plObjectMetaData<KEY, VALUE>::Storage;
 
  plObjectMetaData();
 
  bool HasMetaData(const KEY objectKey) const;
 
  void ClearMetaData(const KEY objectKey);
 
  const VALUE* BeginReadMetaData(const KEY objectKey) const;
  void EndReadMetaData() const;
 
  VALUE* BeginModifyMetaData(const KEY objectKey);
  void EndModifyMetaData(plUInt32 uiModifiedFlags = 0xFFFFFFFF);
 
 
  plMutex& GetMutex() const { return m_pMetaStorage->m_Mutex; }
 
  const VALUE& GetDefaultValue() const { return m_DefaultValue; }
 
  void AttachMetaDataToAbstractGraph(plAbstractObjectGraph& inout_graph) const;
 
  void RestoreMetaDataFromAbstractGraph(const plAbstractObjectGraph& graph);
 
  plSharedPtr<plMetaStorageType> SwapStorage(plSharedPtr<plMetaStorageType> pNewStorage);
  plSharedPtr<plMetaStorageType> GetStorage() { return m_pMetaStorage; }
 
private:
  VALUE m_DefaultValue;
  plSharedPtr<plMetaStorageType> m_pMetaStorage;
  typename plEvent<const EventData&>::Unsubscriber m_EventsUnsubscriber;
};
 
#include <ToolsFoundation/Object/Implementation/ObjectMetaData_inl.h>