/*     Copyright 2019 Diligent Graphics LLC
 *  
 *  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
 * 
 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF ANY PROPRIETARY RIGHTS.
 *
 *  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.h"
#include "GLContext.h"
#include "VAOCache.h"
#include "BaseInterfacesGL.h"
#include "FBOCache.h"
#include "TexRegionRender.h"

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

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

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

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

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

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

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

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

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

    void CreateDummyTexture(const TextureDesc& TexDesc, RESOURCE_STATE InitialState, class TextureBaseGL** ppTexture);

    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
