/*
 *  Copyright 2019-2020 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 "RenderDeviceBase.hpp"
#include "GLContext.hpp"
#include "VAOCache.hpp"
#include "BaseInterfacesGL.h"
#include "FBOCache.hpp"
#include "TexRegionRender.hpp"

enum class GPU_VENDOR
{
    UNKNOWN,
    INTEL,
    ATI,
    NVIDIA,
    QUALCOMM
};

struct GPUInfo
{
    GPU_VENDOR Vendor = GPU_VENDOR::UNKNOWN;
};

namespace Diligent
{

/// Render device implementation in OpenGL backend.
// RenderDeviceGLESImpl is inherited from RenderDeviceGLImpl
class RenderDeviceGLImpl : public RenderDeviceBase<IGLDeviceBaseInterface>
{
public:
    using TRenderDeviceBase = RenderDeviceBase<IGLDeviceBaseInterface>;

    RenderDeviceGLImpl(IReferenceCounters*       pRefCounters,
                       IMemoryAllocator&         RawMemAllocator,
                       IEngineFactory*           pEngineFactory,
                       const EngineGLCreateInfo& InitAttribs,
                       const SwapChainDesc*      pSCDesc = nullptr);
    ~RenderDeviceGLImpl();

    virtual void DILIGENT_CALL_TYPE QueryInterface(const INTERFACE_ID& IID, IObject** ppInterface) override;

    /// Implementation of IRenderDevice::CreateBuffer() in OpenGL backend.
    void                            CreateBuffer(const BufferDesc& BuffDesc,
                                                 const BufferData* pBuffData,
                                                 IBuffer**         ppBuffer,
                                                 bool              bIsDeviceInternal);
    virtual void DILIGENT_CALL_TYPE CreateBuffer(const BufferDesc& BuffDesc,
                                                 const BufferData* BuffData,
                                                 IBuffer**         ppBuffer) override final;

    /// Implementation of IRenderDevice::CreateShader() in OpenGL backend.
    void                            CreateShader(const ShaderCreateInfo& ShaderCreateInfo,
                                                 IShader**               ppShader,
                                                 bool                    bIsDeviceInternal);
    virtual void DILIGENT_CALL_TYPE CreateShader(const ShaderCreateInfo& ShaderCreateInfo,
                                                 IShader**               ppShader) override final;

    /// Implementation of IRenderDevice::CreateTexture() in OpenGL backend.
    void                            CreateTexture(const TextureDesc& TexDesc,
                                                  const TextureData* pData,
                                                  ITexture**         ppTexture,
                                                  bool               bIsDeviceInternal);
    virtual void DILIGENT_CALL_TYPE CreateTexture(const TextureDesc& TexDesc,
                                                  const TextureData* Data,
                                                  ITexture**         ppTexture) override final;

    /// Implementation of IRenderDevice::CreateSampler() in OpenGL backend.
    void                            CreateSampler(const SamplerDesc& SamplerDesc,
                                                  ISampler**         ppSampler,
                                                  bool               bIsDeviceInternal);
    virtual void DILIGENT_CALL_TYPE CreateSampler(const SamplerDesc& SamplerDesc,
                                                  ISampler**         ppSampler) override final;

    /// Implementation of IRenderDevice::CreatePipelineState() in OpenGL backend.
    void                            CreatePipelineState(const PipelineStateCreateInfo& PSOCreateInfo,
                                                        IPipelineState**               ppPipelineState,
                                                        bool                           bIsDeviceInternal);
    virtual void DILIGENT_CALL_TYPE CreatePipelineState(const PipelineStateCreateInfo& PSOCreateInfo,
                                                        IPipelineState**               ppPipelineState) override final;

    /// Implementation of IRenderDevice::CreateFence() in OpenGL backend.
    virtual void DILIGENT_CALL_TYPE CreateFence(const FenceDesc& Desc, IFence** ppFence) override final;

    /// Implementation of IRenderDevice::CreateQuery() in OpenGL backend.
    virtual void DILIGENT_CALL_TYPE CreateQuery(const QueryDesc& Desc, IQuery** ppQuery) override final;

    /// Implementation of IRenderDeviceGL::CreateTextureFromGLHandle().
    virtual void DILIGENT_CALL_TYPE CreateTextureFromGLHandle(Uint32             GLHandle,
                                                              Uint32             GLBindTarget,
                                                              const TextureDesc& TexDesc,
                                                              RESOURCE_STATE     InitialState,
                                                              ITexture**         ppTexture) override final;

    /// Implementation of IRenderDeviceGL::CreateBufferFromGLHandle().
    virtual void DILIGENT_CALL_TYPE CreateBufferFromGLHandle(Uint32            GLHandle,
                                                             const BufferDesc& BuffDesc,
                                                             RESOURCE_STATE    InitialState,
                                                             IBuffer**         ppBuffer) override final;

    /// Implementation of IRenderDeviceGL::CreateDummyTexture().
    virtual void DILIGENT_CALL_TYPE CreateDummyTexture(const TextureDesc& TexDesc,
                                                       RESOURCE_STATE     InitialState,
                                                       ITexture**         ppTexture) override final;

    /// Implementation of IRenderDevice::ReleaseStaleResources() in OpenGL backend.
    virtual void DILIGENT_CALL_TYPE ReleaseStaleResources(bool ForceRelease = false) override final {}

    /// Implementation of IRenderDevice::IdleGPU() in OpenGL backend.
    virtual void DILIGENT_CALL_TYPE IdleGPU() override final;

    const GPUInfo& GetGPUInfo() { return m_GPUInfo; }

    FBOCache& GetFBOCache(GLContext::NativeGLContextType Context);
    void      OnReleaseTexture(ITexture* pTexture);

    VAOCache& GetVAOCache(GLContext::NativeGLContextType Context);
    void      OnDestroyPSO(IPipelineState* pPSO);
    void      OnDestroyBuffer(IBuffer* pBuffer);

    size_t GetCommandQueueCount() const { return 1; }
    Uint64 GetCommandQueueMask() const { return Uint64{1}; }

    void InitTexRegionRender();

protected:
    friend class DeviceContextGLImpl;
    friend class TextureBaseGL;
    friend class PipelineStateGLImpl;
    friend class ShaderGLImpl;
    friend class BufferGLImpl;
    friend class TextureViewGLImpl;
    friend class SwapChainGLImpl;
    friend class GLContextState;

    // Must be the first member because its constructor initializes OpenGL
    GLContext m_GLContext;

    std::unordered_set<String> m_ExtensionStrings;

    ThreadingTools::LockFlag                                     m_VAOCacheLockFlag;
    std::unordered_map<GLContext::NativeGLContextType, VAOCache> m_VAOCache;

    ThreadingTools::LockFlag                                     m_FBOCacheLockFlag;
    std::unordered_map<GLContext::NativeGLContextType, FBOCache> m_FBOCache;

    GPUInfo m_GPUInfo;

    std::unique_ptr<TexRegionRender> m_pTexRegionRender;

private:
    virtual void TestTextureFormat(TEXTURE_FORMAT TexFormat) override final;
    bool         CheckExtension(const Char* ExtensionString);
    void         FlagSupportedTexFormats();
    void         QueryDeviceCaps();
};

} // namespace Diligent
