/*
 *  Copyright 2019-2021 Diligent Graphics LLC
 *  Copyright 2015-2019 Egor Yusov
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *  In no event and under no legal theory, whether in tort (including negligence),
 *  contract, or otherwise, unless required by applicable law (such as deliberate
 *  and grossly negligent acts) or agreed to in writing, shall any Contributor be
 *  liable for any damages, including any direct, indirect, special, incidental,
 *  or consequential damages of any character arising as a result of this License or
 *  out of the use or inability to use the software (including but not limited to damages
 *  for loss of goodwill, work stoppage, computer failure or malfunction, or any and
 *  all other commercial damages or losses), even if such Contributor has been advised
 *  of the possibility of such damages.
 */

#pragma once

#include <memory>
#include "../../../DiligentCore/Primitives/interface/BasicTypes.h"
#include "../../../DiligentCore/Common/interface/BasicMath.hpp"
#include "../../../DiligentCore/Common/interface/RefCntAutoPtr.hpp"
#include "../../../DiligentCore/Graphics/GraphicsEngine/interface/GraphicsTypes.h"
#include "imgui.h"

struct ImDrawData;

namespace Diligent
{

struct IRenderDevice;
struct IDeviceContext;
struct IBuffer;
struct IPipelineState;
struct ITextureView;
struct IShaderResourceBinding;
struct IShaderResourceVariable;
enum TEXTURE_FORMAT : Uint16;
enum SURFACE_TRANSFORM : Uint32;

class ImGuiDiligentRenderer
{
public:
    ImGuiDiligentRenderer(IRenderDevice* pDevice,
                          TEXTURE_FORMAT BackBufferFmt,
                          TEXTURE_FORMAT DepthBufferFmt,
                          Uint32         InitialVertexBufferSize,
                          Uint32         InitialIndexBufferSize);
    ~ImGuiDiligentRenderer();
    void NewFrame(Uint32            RenderSurfaceWidth,
                  Uint32            RenderSurfaceHeight,
                  SURFACE_TRANSFORM SurfacePreTransform);
    void EndFrame();
    void RenderDrawData(IDeviceContext* pCtx, ImDrawData* pDrawData);
    void InvalidateDeviceObjects();
    void CreateDeviceObjects();
    void CreateFontsTexture();

private:
    inline float4 TransformClipRect(const ImVec2& DisplaySize, const float4& rect) const;

private:
    RefCntAutoPtr<IRenderDevice>          m_pDevice;
    RefCntAutoPtr<IBuffer>                m_pVB;
    RefCntAutoPtr<IBuffer>                m_pIB;
    RefCntAutoPtr<IBuffer>                m_pVertexConstantBuffer;
    RefCntAutoPtr<IPipelineState>         m_pPSO;
    RefCntAutoPtr<ITextureView>           m_pFontSRV;
    RefCntAutoPtr<IShaderResourceBinding> m_pSRB;
    IShaderResourceVariable*              m_pTextureVar = nullptr;

    const TEXTURE_FORMAT m_BackBufferFmt;
    const TEXTURE_FORMAT m_DepthBufferFmt;
    Uint32               m_VertexBufferSize    = 0;
    Uint32               m_IndexBufferSize     = 0;
    Uint32               m_RenderSurfaceWidth  = 0;
    Uint32               m_RenderSurfaceHeight = 0;
    SURFACE_TRANSFORM    m_SurfacePreTransform = SURFACE_TRANSFORM_IDENTITY;
};

} // namespace Diligent