BansheeEngine/BansheeD3D9RenderSystem/Include/CmD3D9IndexBuffer.h

#pragma once

#include "CmD3D9Prerequisites.h"
#include "CmIndexBuffer.h"
#include "CmD3D9Resource.h"

namespace BansheeEngine 
{ 
    class BS_D3D9_EXPORT D3D9IndexBuffer : public IndexBuffer, public D3D9Resource
    {
	protected:
		struct BufferResources
		{
			IDirect3DIndexBuffer9* mBuffer;
			bool mOutOfDate;
			UINT32 mLockOffset;
			UINT32 mLockLength;
			GpuLockOptions mLockOptions;
		};

    public:
        ~D3D9IndexBuffer();

        /** See HardwareBuffer. */
        void readData(UINT32 offset, UINT32 length, void* dest);
        /** See HardwareBuffer. */
		void writeData(UINT32 offset, UINT32 length, const void* source, BufferWriteType writeFlags = BufferWriteType::Normal);

		/**
		 * @copydoc	D3D9Resource::notifyOnDeviceCreate
		 */
		virtual void notifyOnDeviceCreate(IDirect3DDevice9* d3d9Device);

		/**
		 * @copydoc	D3D9Resource::notifyOnDeviceDestroy
		 */
		virtual void notifyOnDeviceDestroy(IDirect3DDevice9* d3d9Device);

		/**
		 * @copydoc	D3D9Resource::notifyOnDeviceLost
		 */
		virtual void notifyOnDeviceLost(IDirect3DDevice9* d3d9Device);

		/**
		 * @copydoc	D3D9Resource::notifyOnDeviceReset
		 */
		virtual void notifyOnDeviceReset(IDirect3DDevice9* d3d9Device);

		// Create the actual index buffer.
		void createBuffer(IDirect3DDevice9* d3d9Device, D3DPOOL ePool);
	
		/// Get the D3D-specific index buffer
        IDirect3DIndexBuffer9* getD3DIndexBuffer();		

	protected:
		friend class D3D9HardwareBufferManager;

		D3D9IndexBuffer(IndexType idxType, UINT32 numIndexes, GpuBufferUsage usage, bool useSystemMem);

		/** See HardwareBuffer. */
		void* lockImpl(UINT32 offset, UINT32 length, GpuLockOptions options);
		/** See HardwareBuffer. */
		void unlockImpl();
		// updates buffer resources from system memory buffer.
		bool updateBufferResources(const UINT8* systemMemoryBuffer, BufferResources* bufferResources);

		/**
		 * @copydoc IndexBuffer::initialize_internal()
		 */
		void initialize_internal();	
		
		/**
		 * @copydoc IndexBuffer::destroy_internal()
		 */
		void destroy_internal();

	protected:		
		Map<IDirect3DDevice9*, BufferResources*> mMapDeviceToBufferResources;	// Map between device to buffer resources.	
		D3DINDEXBUFFER_DESC	mBufferDesc;					// Buffer description.		
		UINT8* mSystemMemoryBuffer;			// Consistent system memory buffer for multiple devices support.
    };
}