#pragma region CPL License
/*
Nuclex Native Framework
Copyright (C) 2002-2013 Nuclex Development Labs

This library is free software; you can redistribute it and/or
modify it under the terms of the IBM Common Public License as
published by the IBM Corporation; either version 1.0 of the
License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
IBM Common Public License for more details.

You should have received a copy of the IBM Common Public
License along with this library
*/
#pragma endregion // CPL License

#ifndef NUCLEX_GRAPHICS_RASTERIZATION_DIRECT3D11RENDERTARGET2OBSERVER_H
#define NUCLEX_GRAPHICS_RASTERIZATION_DIRECT3D11RENDERTARGET2OBSERVER_H

#include "Nuclex/Graphics/Config.h"
#include "Nuclex/Graphics/Rasterization/RenderTarget2.h"
#include "../Direct3D11Api.h"

namespace Nuclex { namespace Graphics { namespace Rasterization {

  // ------------------------------------------------------------------------------------------- //

  class Direct3D11RasterizerResources;

  // ------------------------------------------------------------------------------------------- //

}}} // namespace Nuclex::Graphics::Rasterization

namespace Nuclex { namespace Graphics { namespace Rasterization {

  // ------------------------------------------------------------------------------------------- //

  ///<summary>Manages an attached Direct3D 11 render target texture</summary>
  class Direct3D11RenderTarget2Observer : public RenderTarget2::BackingObserver {

    /// <summary>Initializes a new Direct3D 11 render target texture</summary>
    /// <param name="renderTarget">Render target the observer is attached to</param>
    /// <param name="resources">Manager the render target belongs to</param>
    /// <param name="swapChain">Swap chain the render target is part of</param>
    public: Direct3D11RenderTarget2Observer(
      Direct3D11RasterizerResources &resources, RenderTarget2 *renderTarget,
      const IDXGISwapChainNPtr &swapChain
    );

    /// <summary>Initializes a new Direct3D 11 render target texture</summary>
    /// <param name="renderTarget">Render target the observer is attached to</param>
    /// <param name="resources">Manager the render target belongs to</param>
    public: Direct3D11RenderTarget2Observer(
      Direct3D11RasterizerResources &resources, RenderTarget2 *renderTarget
    );

    /// <summary>Frees all resources owned by the rasterizer settings container</summary>
    public: virtual ~Direct3D11RenderTarget2Observer() {}

    /// <summary>Called right before the texture is destroyed</summary>
    public: void Destroying();

    /// <summary>Resizes the render target to the specified width and height</summary>
    /// <param name="width">New width of the render target</param>
    /// <param name="height">New height of the render target</param>
    public: void Resized(std::size_t width, std::size_t height);

    /// <summary>Called when the render target has been cleared</summary>
    public: void Cleared();

    /// <summary>Clears the render target to the specified values</summary>
    /// <param name="color">Color the render target will be cleared to</param>
    /// <param name="depth">Depth value the depth buffer will be cleared to</param>
    /// <param name="stencil">Stencil bits the stencil buffer will be cleared to</param>
    public: void Cleared(Color color, float depth, std::uint8_t stencil);

    /// <summary>Called when the render target has been modified</summary>
    /// <param name="changedBox">Box around the changed area</param>
    public: void Changed(const Box &changedBox);

    /// <summary>Reads the specified region of the render target</summary>
    /// <param name="region">Region of the render target that will be read</param>
    /// <param name="target">
    ///   Address at which the render target's pixels will be deposited
    /// </param>
    /// <param name="targetStride">Bytes required to get from one line to the next</param>
    public: void Read(const Rectangle &region, void *target, std::size_t targetStride);

    /// <summary>Retrieves the agnostic render target being observed</summary>
    /// <returns>The agnostic render target being observed</returns>
    public: RenderTarget2 *GetResource() const {
      return this->renderTarget2;
    }

    /// <summary>Returns the active view into the render target</summary>
    /// <returns>The render target's active view</returns>
    public: const ID3D11RenderTargetViewPtr &GetDirect3DRenderTargetView() const {
      return this->renderTargetView;
    }

    /// <summary>Returns the active view into the depth and stencil buffer</summary>
    /// <returns>The depth and stencil buffer's active view</returns>
    public: const ID3D11DepthStencilViewPtr &GetDirect3DDepthStencilView() const {
      return this->depthStencilView;
    }

    /// <summary>
    ///   Called by the rasterizer to shut down the render target before the swap chain
    ///   is recreated.
    /// </summary>
    public: void ShutdownForSwapChainRecreation();

    /// <summary>
    ///   Called by the rasterizer after the swap chain has been recreated to create
    ///   a new render target on the new swap chain.
    /// </summary>
    /// <param name="width">New width of the primary render target</param>
    /// <param name="height">New height of the primary render target</param>
    public: void RestoreAfterSwapChainRecreation(std::size_t width, std::size_t height);

    /// <summary>Retrieves the back buffer texture from a swap chain</summary>
    /// <param name="swapChain">Swap chain from which the back buffer will be retrieved</param>
    /// <returns>The swap chain's back buffer as a texture</returns>
    private: static ID3D11Texture2DPtr getTextureFromSwapChain(
      const IDXGISwapChainNPtr &swapChain
    );

    /// <summary>Creates a view through which the render target can be accessed</summary>
    private: void createRenderTargetView();
    /// <summary>Creates the depth buffer for the render target</summary>
    private: void createDepthBuffer();
    /// <summary>Creates a view thorugh which the depth buffer can be accessed</param>
    private: void createDepthView();

    private: Direct3D11RenderTarget2Observer(const Direct3D11RenderTarget2Observer &);
    private: Direct3D11RenderTarget2Observer &operator =(const Direct3D11RenderTarget2Observer &);

    /// <summary>Render target this observer is attached to</summary>
    private: RenderTarget2 *renderTarget2;
    /// <summary>Swap chain whose back buffer the render target represents</summary>
    /// <remarks>
    ///   This field is only set if the render target is part of a swap chain (which right
    ///   now only holds true for the primary render target)
    /// </remarks>
    private: IDXGISwapChainNPtr swapChain;
    /// <summary>Texture holding the render target's contents</summary>
    private: ID3D11Texture2DPtr renderTargetTexture;
    /// <summary>View through which the render target can be accessed</summary>
    private: ID3D11RenderTargetViewPtr renderTargetView;
    /// <summary>Texture holding the render target's depth and stencil buffer</summary>
    private: ID3D11Texture2DPtr depthStencilTexture;
    /// <summary>View through which the render target can be accessed</summary>
    private: ID3D11DepthStencilViewPtr depthStencilView;
    /// <summary>Resource manager the render target belongs to</summary>
    private: Direct3D11RasterizerResources &resources;

  };

  // ------------------------------------------------------------------------------------------- //

}}} // namespace Nuclex::Graphics::Rasterization

#endif // NUCLEX_GRAPHICS_RASTERIZATION_DIRECT3D11RENDERTARGET2OBSERVER_H