#include "boo/graphicsdev/GL.hpp"
#include "boo/graphicsdev/glew.h"
#include "boo/IApplication.hpp"
#include "Common.hpp"
#include <thread>
#include <condition_variable>
#include <array>
#include <unordered_map>
#include <unordered_set>
#include "xxhash.h"

#include "logvisor/logvisor.hpp"

#undef min
#undef max

namespace boo
{
static logvisor::Module Log("boo::GL");
class GLDataFactoryImpl;

struct GLShareableShader : IShareableShader<GLDataFactoryImpl, GLShareableShader>
{
    GLuint m_shader = 0;
    GLShareableShader(GLDataFactoryImpl& fac, uint64_t srcKey, GLuint s)
    : IShareableShader(fac, srcKey, 0), m_shader(s) {}
    ~GLShareableShader() { glDeleteShader(m_shader); }
};

class GLDataFactoryImpl : public GLDataFactory, public GraphicsDataFactoryHead
{
    friend struct GLCommandQueue;
    friend class GLDataFactory::Context;
    IGraphicsContext* m_parent;
    uint32_t m_drawSamples;
    std::unordered_map<uint64_t, std::unique_ptr<GLShareableShader>> m_sharedShaders;
public:
    GLDataFactoryImpl(IGraphicsContext* parent, uint32_t drawSamples)
    : m_parent(parent), m_drawSamples(drawSamples) {}

    Platform platform() const { return Platform::OpenGL; }
    const SystemChar* platformName() const { return _S("OpenGL"); }
    void commitTransaction(const FactoryCommitFunc&);
    ObjToken<IGraphicsBufferD> newPoolBuffer(BufferUse use, size_t stride, size_t count);
    void _unregisterShareableShader(uint64_t srcKey, uint64_t binKey) { m_sharedShaders.erase(srcKey); }
};

static const GLenum USE_TABLE[] =
{
    GL_INVALID_ENUM,
    GL_ARRAY_BUFFER,
    GL_ELEMENT_ARRAY_BUFFER,
    GL_UNIFORM_BUFFER
};

class GLGraphicsBufferS : public GraphicsDataNode<IGraphicsBufferS>
{
    friend class GLDataFactory;
    friend struct GLCommandQueue;
    GLuint m_buf;
    GLenum m_target;
    GLGraphicsBufferS(const ObjToken<BaseGraphicsData>& parent, BufferUse use, const void* data, size_t sz)
    : GraphicsDataNode<IGraphicsBufferS>(parent)
    {
        m_target = USE_TABLE[int(use)];
        glGenBuffers(1, &m_buf);
        glBindBuffer(m_target, m_buf);
        glBufferData(m_target, sz, data, GL_STATIC_DRAW);
    }
public:
    ~GLGraphicsBufferS() { glDeleteBuffers(1, &m_buf); }

    void bindVertex() const
    {glBindBuffer(GL_ARRAY_BUFFER, m_buf);}
    void bindIndex() const
    {glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_buf);}
    void bindUniform(size_t idx) const
    {glBindBufferBase(GL_UNIFORM_BUFFER, idx, m_buf);}
    void bindUniformRange(size_t idx, GLintptr off, GLsizeiptr size) const
    {glBindBufferRange(GL_UNIFORM_BUFFER, idx, m_buf, off, size);}
};

template<class DataCls>
class GLGraphicsBufferD : public GraphicsDataNode<IGraphicsBufferD, DataCls>
{
    friend class GLDataFactory;
    friend class GLDataFactoryImpl;
    friend struct GLCommandQueue;
    GLuint m_bufs[3];
    GLenum m_target;
    std::unique_ptr<uint8_t[]> m_cpuBuf;
    size_t m_cpuSz = 0;
    int m_validMask = 0;
    GLGraphicsBufferD(const ObjToken<DataCls>& parent, BufferUse use, size_t sz)
    : GraphicsDataNode<IGraphicsBufferD, DataCls>(parent),
      m_target(USE_TABLE[int(use)]), m_cpuBuf(new uint8_t[sz]), m_cpuSz(sz)
    {
        glGenBuffers(3, m_bufs);
        for (int i=0 ; i<3 ; ++i)
        {
            glBindBuffer(m_target, m_bufs[i]);
            glBufferData(m_target, m_cpuSz, nullptr, GL_STREAM_DRAW);
        }
    }
public:
    ~GLGraphicsBufferD() { glDeleteBuffers(3, m_bufs); }

    void update(int b)
    {
        int slot = 1 << b;
        if ((slot & m_validMask) == 0)
        {
            glBindBuffer(m_target, m_bufs[b]);
            glBufferSubData(m_target, 0, m_cpuSz, m_cpuBuf.get());
            m_validMask |= slot;
        }
    }

    void load(const void* data, size_t sz)
    {
        size_t bufSz = std::min(sz, m_cpuSz);
        memcpy(m_cpuBuf.get(), data, bufSz);
        m_validMask = 0;
    }
    void* map(size_t sz)
    {
        if (sz < m_cpuSz)
            return nullptr;
        return m_cpuBuf.get();
    }
    void unmap()
    {
        m_validMask = 0;
    }
    void bindVertex(int b)
    {glBindBuffer(GL_ARRAY_BUFFER, m_bufs[b]);}
    void bindIndex(int b)
    {glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_bufs[b]);}
    void bindUniform(size_t idx, int b)
    {glBindBufferBase(GL_UNIFORM_BUFFER, idx, m_bufs[b]);}
    void bindUniformRange(size_t idx, GLintptr off, GLsizeiptr size, int b)
    {glBindBufferRange(GL_UNIFORM_BUFFER, idx, m_bufs[b], off, size);}
};

ObjToken<IGraphicsBufferS>
GLDataFactory::Context::newStaticBuffer(BufferUse use, const void* data, size_t stride, size_t count)
{
    return {new GLGraphicsBufferS(m_data, use, data, stride * count)};
}

static void SetClampMode(GLenum target, TextureClampMode clampMode)
{
    switch (clampMode)
    {
    case TextureClampMode::Repeat:
    {
        glTexParameteri(target, GL_TEXTURE_WRAP_S, GL_REPEAT);
        glTexParameteri(target, GL_TEXTURE_WRAP_T, GL_REPEAT);
        glTexParameteri(target, GL_TEXTURE_WRAP_R, GL_REPEAT);
        break;
    }
    case TextureClampMode::ClampToWhite:
    {
        glTexParameteri(target, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
        glTexParameteri(target, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
        glTexParameteri(target, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_BORDER);
        GLfloat color[] = {1.f, 1.f, 1.f, 1.f};
        glTexParameterfv(target, GL_TEXTURE_BORDER_COLOR, color);
        break;
    }
    }
}

class GLTextureS : public GraphicsDataNode<ITextureS>
{
    friend class GLDataFactory;
    GLuint m_tex;
    GLTextureS(const ObjToken<BaseGraphicsData>& parent, size_t width, size_t height, size_t mips,
               TextureFormat fmt, TextureClampMode clampMode, const void* data, size_t sz)
    : GraphicsDataNode<ITextureS>(parent)
    {
        const uint8_t* dataIt = static_cast<const uint8_t*>(data);
        glGenTextures(1, &m_tex);
        glBindTexture(GL_TEXTURE_2D, m_tex);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        if (mips > 1)
        {
            glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
            glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, mips-1);
        }
        else
            glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

        SetClampMode(GL_TEXTURE_2D, clampMode);

        GLenum intFormat, format;
        int pxPitch;
        bool compressed = false;
        switch (fmt)
        {
        case TextureFormat::RGBA8:
            intFormat = GL_RGBA8;
            format = GL_RGBA;
            pxPitch = 4;
            break;
        case TextureFormat::I8:
            intFormat = GL_R8;
            format = GL_RED;
            pxPitch = 1;
            break;
        case TextureFormat::DXT1:
            intFormat = GL_COMPRESSED_RGBA_S3TC_DXT1_EXT;
            compressed = true;
            break;
        default:
            Log.report(logvisor::Fatal, "unsupported tex format");
        }

        if (compressed)
        {
            for (size_t i=0 ; i<mips ; ++i)
            {
                size_t dataSz = width * height / 2;
                glCompressedTexImage2D(GL_TEXTURE_2D, i, intFormat, width, height, 0, dataSz, dataIt);
                dataIt += dataSz;
                if (width > 1)
                    width /= 2;
                if (height > 1)
                    height /= 2;
            }
        }
        else
        {
            for (size_t i=0 ; i<mips ; ++i)
            {
                glTexImage2D(GL_TEXTURE_2D, i, intFormat, width, height, 0, format, GL_UNSIGNED_BYTE, dataIt);
                dataIt += width * height * pxPitch;
                if (width > 1)
                    width /= 2;
                if (height > 1)
                    height /= 2;
            }
        }
    }
public:
    ~GLTextureS() { glDeleteTextures(1, &m_tex); }

    void bind(size_t idx) const
    {
        glActiveTexture(GL_TEXTURE0 + idx);
        glBindTexture(GL_TEXTURE_2D, m_tex);
    }
};

class GLTextureSA : public GraphicsDataNode<ITextureSA>
{
    friend class GLDataFactory;
    GLuint m_tex;
    GLTextureSA(const ObjToken<BaseGraphicsData>& parent, size_t width, size_t height, size_t layers, size_t mips,
                TextureFormat fmt, TextureClampMode clampMode, const void* data, size_t sz)
    : GraphicsDataNode<ITextureSA>(parent)
    {
        const uint8_t* dataIt = static_cast<const uint8_t*>(data);
        glGenTextures(1, &m_tex);
        glBindTexture(GL_TEXTURE_2D_ARRAY, m_tex);
        glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        if (mips > 1)
        {
            glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
            glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_MAX_LEVEL, mips-1);
        }
        else
            glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

        SetClampMode(GL_TEXTURE_2D_ARRAY, clampMode);

        GLenum intFormat, format;
        int pxPitch;
        if (fmt == TextureFormat::RGBA8)
        {
            intFormat = GL_RGBA8;
            format = GL_RGBA;
            pxPitch = 4;
        }
        else if (fmt == TextureFormat::I8)
        {
            intFormat = GL_R8;
            format = GL_RED;
            pxPitch = 1;
        }

        for (size_t i=0 ; i<mips ; ++i)
        {
            glTexImage3D(GL_TEXTURE_2D_ARRAY, i, intFormat, width, height, layers, 0, format, GL_UNSIGNED_BYTE, dataIt);
            dataIt += width * height * layers * pxPitch;
            if (width > 1)
                width /= 2;
            if (height > 1)
                height /= 2;
        }
    }
public:
    ~GLTextureSA() { glDeleteTextures(1, &m_tex); }

    void bind(size_t idx) const
    {
        glActiveTexture(GL_TEXTURE0 + idx);
        glBindTexture(GL_TEXTURE_2D_ARRAY, m_tex);
    }
};

class GLTextureD : public GraphicsDataNode<ITextureD>
{
    friend class GLDataFactory;
    friend struct GLCommandQueue;
    GLuint m_texs[3];
    std::unique_ptr<uint8_t[]> m_cpuBuf;
    size_t m_cpuSz = 0;
    GLenum m_intFormat, m_format;
    size_t m_width = 0;
    size_t m_height = 0;
    int m_validMask = 0;
    GLTextureD(const ObjToken<BaseGraphicsData>& parent, size_t width, size_t height,
               TextureFormat fmt, TextureClampMode clampMode)
    : GraphicsDataNode<ITextureD>(parent), m_width(width), m_height(height)
    {
        int pxPitch = 4;
        switch (fmt)
        {
        case TextureFormat::RGBA8:
            m_intFormat = GL_RGBA8;
            m_format = GL_RGBA;
            pxPitch = 4;
            break;
        case TextureFormat::I8:
            m_intFormat = GL_R8;
            m_format = GL_RED;
            pxPitch = 1;
            break;
        default:
            Log.report(logvisor::Fatal, "unsupported tex format");
        }
        m_cpuSz = width * height * pxPitch;
        m_cpuBuf.reset(new uint8_t[m_cpuSz]);

        glGenTextures(3, m_texs);
        for (int i=0 ; i<3 ; ++i)
        {
            glBindTexture(GL_TEXTURE_2D, m_texs[i]);
            glTexImage2D(GL_TEXTURE_2D, 0, m_intFormat, width, height, 0, m_format, GL_UNSIGNED_BYTE, nullptr);
            glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
            glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
            SetClampMode(GL_TEXTURE_2D, clampMode);
        }
    }

public:
    ~GLTextureD() { glDeleteTextures(3, m_texs); }

    void update(int b)
    {
        int slot = 1 << b;
        if ((slot & m_validMask) == 0)
        {
            glBindTexture(GL_TEXTURE_2D, m_texs[b]);
            glTexImage2D(GL_TEXTURE_2D, 0, m_intFormat, m_width, m_height, 0, m_format, GL_UNSIGNED_BYTE, m_cpuBuf.get());
            m_validMask |= slot;
        }
    }

    void load(const void* data, size_t sz)
    {
        size_t bufSz = std::min(sz, m_cpuSz);
        memcpy(m_cpuBuf.get(), data, bufSz);
        m_validMask = 0;
    }
    void* map(size_t sz)
    {
        if (sz > m_cpuSz)
            return nullptr;
        return m_cpuBuf.get();
    }
    void unmap()
    {
        m_validMask = 0;
    }

    void bind(size_t idx, int b)
    {
        glActiveTexture(GL_TEXTURE0 + idx);
        glBindTexture(GL_TEXTURE_2D, m_texs[b]);
    }
};

#define MAX_BIND_TEXS 4

class GLTextureR : public GraphicsDataNode<ITextureR>
{
    friend class GLDataFactory;
    friend struct GLCommandQueue;
    struct GLCommandQueue* m_q;
    GLuint m_texs[2] = {};
    GLuint m_bindTexs[2][MAX_BIND_TEXS] = {};
    GLuint m_fbo = 0;
    size_t m_width = 0;
    size_t m_height = 0;
    size_t m_samples = 0;
    GLenum m_target;
    GLTextureR(const ObjToken<BaseGraphicsData>& parent, GLCommandQueue* q, size_t width, size_t height, size_t samples,
               TextureClampMode clampMode, size_t colorBindCount, size_t depthBindCount);
public:
    ~GLTextureR()
    {
        glDeleteTextures(2, m_texs);
        glDeleteTextures(MAX_BIND_TEXS * 2, m_bindTexs[0]);
        glDeleteFramebuffers(1, &m_fbo);
    }

    void bind(size_t idx, int bindIdx, bool depth) const
    {
        glActiveTexture(GL_TEXTURE0 + idx);
        glBindTexture(m_target, m_bindTexs[depth][bindIdx]);
    }

    void resize(size_t width, size_t height)
    {
        m_width = width;
        m_height = height;

        if (m_samples > 1)
        {
            glBindTexture(GL_TEXTURE_2D_MULTISAMPLE, m_texs[0]);
            glTexImage2DMultisample(GL_TEXTURE_2D_MULTISAMPLE, m_samples, GL_RGBA, width, height, GL_FALSE);
            glBindTexture(GL_TEXTURE_2D_MULTISAMPLE, m_texs[1]);
            glTexImage2DMultisample(GL_TEXTURE_2D_MULTISAMPLE, m_samples, GL_DEPTH_COMPONENT24, width, height, GL_FALSE);
        }
        else
        {
            glBindTexture(GL_TEXTURE_2D, m_texs[0]);
            glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
            glBindTexture(GL_TEXTURE_2D, m_texs[1]);
            glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT24, width, height, 0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, nullptr);

            glBindFramebuffer(GL_FRAMEBUFFER, m_fbo);
            glDepthMask(GL_TRUE);
            glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        }

        for (int i=0 ; i<MAX_BIND_TEXS ; ++i)
        {
            if (m_bindTexs[0][i])
            {
                glBindTexture(GL_TEXTURE_2D, m_bindTexs[0][i]);
                glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
            }
        }

        for (int i=0 ; i<MAX_BIND_TEXS ; ++i)
        {
            if (m_bindTexs[1][i])
            {
                glBindTexture(GL_TEXTURE_2D, m_bindTexs[1][i]);
                glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT24, width, height, 0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, nullptr);
            }
        }
    }
};

ObjToken<ITextureS>
GLDataFactory::Context::newStaticTexture(size_t width, size_t height, size_t mips, TextureFormat fmt,
                                         TextureClampMode clampMode, const void* data, size_t sz)
{
    return {new GLTextureS(m_data, width, height, mips, fmt, clampMode, data, sz)};
}

ObjToken<ITextureSA>
GLDataFactory::Context::newStaticArrayTexture(size_t width, size_t height, size_t layers, size_t mips,
                                              TextureFormat fmt, TextureClampMode clampMode,
                                              const void *data, size_t sz)
{
    return {new GLTextureSA(m_data, width, height, layers, mips, fmt, clampMode, data, sz)};
}

class GLShaderPipeline : public GraphicsDataNode<IShaderPipeline>
{
    friend class GLDataFactory;
    friend struct GLCommandQueue;
    friend struct GLShaderDataBinding;
    mutable GLShareableShader::Token m_vert;
    mutable GLShareableShader::Token m_frag;
    mutable GLuint m_prog = 0;
    GLenum m_sfactor = GL_ONE;
    GLenum m_dfactor = GL_ZERO;
    GLenum m_drawPrim = GL_TRIANGLES;
    ZTest m_depthTest = ZTest::LEqual;
    bool m_depthWrite = true;
    bool m_colorWrite = true;
    bool m_alphaWrite = true;
    bool m_subtractBlend = false;
    CullMode m_culling;
    mutable std::vector<GLint> m_uniLocs;
    mutable std::vector<std::string> m_texNames;
    mutable std::vector<std::string> m_blockNames;
    GLShaderPipeline(const ObjToken<BaseGraphicsData>& parent)
    : GraphicsDataNode<IShaderPipeline>(parent) {}
public:
    ~GLShaderPipeline() { if (m_prog) glDeleteProgram(m_prog); }

    GLuint bind() const
    {
        if (!m_prog)
        {
            m_prog = glCreateProgram();
            if (!m_prog)
            {
                Log.report(logvisor::Error, "unable to create shader program");
                return 0;
            }

            glAttachShader(m_prog, m_vert.get().m_shader);
            glAttachShader(m_prog, m_frag.get().m_shader);

            glLinkProgram(m_prog);

            glDetachShader(m_prog, m_vert.get().m_shader);
            glDetachShader(m_prog, m_frag.get().m_shader);

            m_vert.reset();
            m_frag.reset();

            GLint status;
            glGetProgramiv(m_prog, GL_LINK_STATUS, &status);
            if (status != GL_TRUE)
            {
                GLint logLen;
                glGetProgramiv(m_prog, GL_INFO_LOG_LENGTH, &logLen);
                std::unique_ptr<char[]> log(new char[logLen]);
                glGetProgramInfoLog(m_prog, logLen, nullptr, log.get());
                Log.report(logvisor::Error, "unable to link shader program\n%s\n", log.get());
                return 0;
            }

            glUseProgram(m_prog);

            if (m_blockNames.size())
            {
                m_uniLocs.reserve(m_blockNames.size());
                for (size_t i=0 ; i<m_blockNames.size() ; ++i)
                {
                    GLint uniLoc = glGetUniformBlockIndex(m_prog, m_blockNames[i].c_str());
                    //if (uniLoc < 0)
                    //    Log.report(logvisor::Warning, "unable to find uniform block '%s'", uniformBlockNames[i]);
                    m_uniLocs.push_back(uniLoc);
                }
                m_blockNames = std::vector<std::string>();
            }

            if (m_texNames.size())
            {
                for (int i=0 ; i<m_texNames.size() ; ++i)
                {
                    GLint texLoc = glGetUniformLocation(m_prog, m_texNames[i].c_str());
                    if (texLoc < 0)
                    { /* Log.report(logvisor::Warning, "unable to find sampler variable '%s'", texNames[i]); */ }
                    else
                        glUniform1i(texLoc, i);
                }
                m_texNames = std::vector<std::string>();
            }
        }
        else
        {
            glUseProgram(m_prog);
        }

        if (m_dfactor != GL_ZERO)
        {
            glEnable(GL_BLEND);
            glBlendFuncSeparate(m_sfactor, m_dfactor, GL_ONE, GL_ZERO);
            if (m_subtractBlend)
                glBlendEquation(GL_FUNC_SUBTRACT);
            else
                glBlendEquation(GL_FUNC_ADD);
        }
        else
            glDisable(GL_BLEND);

        if (m_depthTest != ZTest::None)
        {
            glEnable(GL_DEPTH_TEST);
            switch (m_depthTest)
            {
            case ZTest::LEqual:
            default:
                glDepthFunc(GL_LEQUAL);
                break;
            case ZTest::Greater:
                glDepthFunc(GL_GREATER);
                break;
            case ZTest::GEqual:
                glDepthFunc(GL_GEQUAL);
                break;
            case ZTest::Equal:
                glDepthFunc(GL_EQUAL);
                break;
            }
        }
        else
            glDisable(GL_DEPTH_TEST);
        glDepthMask(m_depthWrite);
        glColorMask(m_colorWrite, m_colorWrite, m_colorWrite, m_alphaWrite);

        if (m_culling != CullMode::None)
        {
            glEnable(GL_CULL_FACE);
            glCullFace(m_culling == CullMode::Backface ? GL_BACK : GL_FRONT);
        }
        else
            glDisable(GL_CULL_FACE);

        return m_prog;
    }
};

static const GLenum PRIMITIVE_TABLE[] =
{
    GL_TRIANGLES,
    GL_TRIANGLE_STRIP
};

static const GLenum BLEND_FACTOR_TABLE[] =
{
    GL_ZERO,
    GL_ONE,
    GL_SRC_COLOR,
    GL_ONE_MINUS_SRC_COLOR,
    GL_DST_COLOR,
    GL_ONE_MINUS_DST_COLOR,
    GL_SRC_ALPHA,
    GL_ONE_MINUS_SRC_ALPHA,
    GL_DST_ALPHA,
    GL_ONE_MINUS_DST_ALPHA,
    GL_SRC1_COLOR,
    GL_ONE_MINUS_SRC1_COLOR
};

ObjToken<IShaderPipeline> GLDataFactory::Context::newShaderPipeline
(const char* vertSource, const char* fragSource,
 size_t texCount, const char** texNames,
 size_t uniformBlockCount, const char** uniformBlockNames,
 BlendFactor srcFac, BlendFactor dstFac, Primitive prim,
 ZTest depthTest, bool depthWrite, bool colorWrite,
 bool alphaWrite, CullMode culling)
{
    GLDataFactoryImpl& factory = static_cast<GLDataFactoryImpl&>(m_parent);
    ObjToken<IShaderPipeline> retval(new GLShaderPipeline(m_data));
    GLShaderPipeline& shader = *retval.cast<GLShaderPipeline>();

    XXH64_state_t hashState;
    uint64_t hashes[2];
    XXH64_reset(&hashState, 0);
    XXH64_update(&hashState, vertSource, strlen(vertSource));
    hashes[0] = XXH64_digest(&hashState);
    XXH64_reset(&hashState, 0);
    XXH64_update(&hashState, fragSource, strlen(fragSource));
    hashes[1] = XXH64_digest(&hashState);

    GLint status;
    auto vertFind = factory.m_sharedShaders.find(hashes[0]);
    if (vertFind != factory.m_sharedShaders.end())
    {
        shader.m_vert = vertFind->second->lock();
    }
    else
    {
        GLuint sobj = glCreateShader(GL_VERTEX_SHADER);
        if (!sobj)
        {
            Log.report(logvisor::Error, "unable to create vert shader");
            return {};
        }

        glShaderSource(sobj, 1, &vertSource, nullptr);
        glCompileShader(sobj);
        glGetShaderiv(sobj, GL_COMPILE_STATUS, &status);
        if (status != GL_TRUE)
        {
            GLint logLen;
            glGetShaderiv(sobj, GL_INFO_LOG_LENGTH, &logLen);
            std::unique_ptr<char[]> log(new char[logLen]);
            glGetShaderInfoLog(sobj, logLen, nullptr, log.get());
            Log.report(logvisor::Error, "unable to compile vert source\n%s\n%s\n", log.get(), vertSource);
            return {};
        }

        auto it =
        factory.m_sharedShaders.emplace(std::make_pair(hashes[0],
            std::make_unique<GLShareableShader>(factory, hashes[0], sobj))).first;
        shader.m_vert = it->second->lock();
    }
    auto fragFind = factory.m_sharedShaders.find(hashes[1]);
    if (fragFind != factory.m_sharedShaders.end())
    {
        shader.m_frag = fragFind->second->lock();
    }
    else
    {
        GLuint sobj = glCreateShader(GL_FRAGMENT_SHADER);
        if (!sobj)
        {
            Log.report(logvisor::Error, "unable to create frag shader");
            return {};
        }

        glShaderSource(sobj, 1, &fragSource, nullptr);
        glCompileShader(sobj);
        glGetShaderiv(sobj, GL_COMPILE_STATUS, &status);
        if (status != GL_TRUE)
        {
            GLint logLen;
            glGetShaderiv(sobj, GL_INFO_LOG_LENGTH, &logLen);
            std::unique_ptr<char[]> log(new char[logLen]);
            glGetShaderInfoLog(sobj, logLen, nullptr, log.get());
            Log.report(logvisor::Error, "unable to compile frag source\n%s\n%s\n", log.get(), fragSource);
            return {};
        }

        auto it =
        factory.m_sharedShaders.emplace(std::make_pair(hashes[1],
            std::make_unique<GLShareableShader>(factory, hashes[1], sobj))).first;
        shader.m_frag = it->second->lock();
    }

    shader.m_texNames.reserve(texCount);
    for (int i=0 ; i<texCount ; ++i)
        shader.m_texNames.emplace_back(texNames[i]);

    shader.m_blockNames.reserve(uniformBlockCount);
    for (int i=0 ; i<uniformBlockCount ; ++i)
        shader.m_blockNames.emplace_back(uniformBlockNames[i]);

    if (srcFac == BlendFactor::Subtract || dstFac == BlendFactor::Subtract)
    {
        shader.m_sfactor = GL_DST_COLOR;
        shader.m_dfactor = GL_SRC_COLOR;
        shader.m_subtractBlend = true;
    }
    else
    {
        shader.m_sfactor = BLEND_FACTOR_TABLE[int(srcFac)];
        shader.m_dfactor = BLEND_FACTOR_TABLE[int(dstFac)];
        shader.m_subtractBlend = false;
    }

    shader.m_depthTest = depthTest;
    shader.m_depthWrite = depthWrite;
    shader.m_colorWrite = colorWrite;
    shader.m_alphaWrite = alphaWrite;
    shader.m_culling = culling;
    shader.m_drawPrim = PRIMITIVE_TABLE[int(prim)];

    return retval;
}

struct GLVertexFormat : GraphicsDataNode<IVertexFormat>
{
    GLuint m_vao[3] = {};
    GLuint m_baseVert, m_baseInst;
    std::vector<VertexElementDescriptor> m_elements;
    GLVertexFormat(const ObjToken<BaseGraphicsData>& parent, GLCommandQueue* q,
                   size_t elementCount, const VertexElementDescriptor* elements,
                   size_t baseVert, size_t baseInst);
    ~GLVertexFormat() { glDeleteVertexArrays(3, m_vao); }
    void bind(int idx) const { glBindVertexArray(m_vao[idx]); }
};

struct GLShaderDataBinding : GraphicsDataNode<IShaderDataBinding>
{
    ObjToken<IShaderPipeline> m_pipeline;
    ObjToken<IVertexFormat> m_vtxFormat;
    std::vector<ObjToken<IGraphicsBuffer>> m_ubufs;
    std::vector<std::pair<size_t,size_t>> m_ubufOffs;
    struct BoundTex
    {
        ObjToken<ITexture> tex;
        int idx;
        bool depth;
    };
    std::vector<BoundTex> m_texs;

    GLShaderDataBinding(const ObjToken<BaseGraphicsData>& d,
                        const ObjToken<IShaderPipeline>& pipeline,
                        const ObjToken<IVertexFormat>& vtxFormat,
                        size_t ubufCount, const ObjToken<IGraphicsBuffer>* ubufs,
                        const size_t* ubufOffs, const size_t* ubufSizes,
                        size_t texCount, const ObjToken<ITexture>* texs,
                        const int* bindTexIdx,
                        const bool* depthBind)
    : GraphicsDataNode<IShaderDataBinding>(d),
      m_pipeline(pipeline),
      m_vtxFormat(vtxFormat)
    {
        if (ubufOffs && ubufSizes)
        {
            m_ubufOffs.reserve(ubufCount);
            for (size_t i=0 ; i<ubufCount ; ++i)
            {
#ifndef NDEBUG
                if (ubufOffs[i] % 256)
                    Log.report(logvisor::Fatal, "non-256-byte-aligned uniform-offset %d provided to newShaderDataBinding", int(i));
#endif
                m_ubufOffs.emplace_back(ubufOffs[i], (ubufSizes[i] + 255) & ~255);
            }
        }
        m_ubufs.reserve(ubufCount);
        for (size_t i=0 ; i<ubufCount ; ++i)
        {
#ifndef NDEBUG
            if (!ubufs[i])
                Log.report(logvisor::Fatal, "null uniform-buffer %d provided to newShaderDataBinding", int(i));
#endif
            m_ubufs.push_back(ubufs[i]);
        }
        m_texs.reserve(texCount);
        for (size_t i=0 ; i<texCount ; ++i)
        {
            m_texs.push_back({texs[i], bindTexIdx ? bindTexIdx[i] : 0, depthBind ? depthBind[i] : false});
        }
    }
    void bind(int b) const
    {
        GLShaderPipeline& pipeline = *m_pipeline.cast<GLShaderPipeline>();
        GLuint prog = pipeline.bind();
        m_vtxFormat.cast<GLVertexFormat>()->bind(b);
        if (m_ubufOffs.size())
        {
            for (size_t i=0 ; i<m_ubufs.size() && i<pipeline.m_uniLocs.size() ; ++i)
            {
                GLint loc = pipeline.m_uniLocs[i];
                if (loc < 0)
                    continue;
                IGraphicsBuffer* ubuf = m_ubufs[i].get();
                const std::pair<size_t,size_t>& offset = m_ubufOffs[i];
                if (ubuf->dynamic())
                    static_cast<GLGraphicsBufferD<BaseGraphicsData>*>(ubuf)->bindUniformRange(i, offset.first, offset.second, b);
                else
                    static_cast<GLGraphicsBufferS*>(ubuf)->bindUniformRange(i, offset.first, offset.second);
                glUniformBlockBinding(prog, loc, i);
            }
        }
        else
        {
            for (size_t i=0 ; i<m_ubufs.size() && i<pipeline.m_uniLocs.size() ; ++i)
            {
                GLint loc = pipeline.m_uniLocs[i];
                if (loc < 0)
                    continue;
                IGraphicsBuffer* ubuf = m_ubufs[i].get();
                if (ubuf->dynamic())
                    static_cast<GLGraphicsBufferD<BaseGraphicsData>*>(ubuf)->bindUniform(i, b);
                else
                    static_cast<GLGraphicsBufferS*>(ubuf)->bindUniform(i);
                glUniformBlockBinding(prog, loc, i);
            }
        }
        for (size_t i=0 ; i<m_texs.size() ; ++i)
        {
            const BoundTex& tex = m_texs[i];
            if (tex.tex)
            {
                switch (tex.tex->type())
                {
                case TextureType::Dynamic:
                    tex.tex.cast<GLTextureD>()->bind(i, b);
                    break;
                case TextureType::Static:
                    tex.tex.cast<GLTextureS>()->bind(i);
                    break;
                case TextureType::StaticArray:
                    tex.tex.cast<GLTextureSA>()->bind(i);
                    break;
                case TextureType::Render:
                    tex.tex.cast<GLTextureR>()->bind(i, tex.idx, tex.depth);
                    break;
                default: break;
                }
            }
        }
    }
};

ObjToken<IShaderDataBinding>
GLDataFactory::Context::newShaderDataBinding(const ObjToken<IShaderPipeline>& pipeline,
                                             const ObjToken<IVertexFormat>& vtxFormat,
                                             const ObjToken<IGraphicsBuffer>& vbo,
                                             const ObjToken<IGraphicsBuffer>& instVbo,
                                             const ObjToken<IGraphicsBuffer>& ibo,
                                             size_t ubufCount, const ObjToken<IGraphicsBuffer>* ubufs,
                                             const PipelineStage* ubufStages,
                                             const size_t* ubufOffs, const size_t* ubufSizes,
                                             size_t texCount, const ObjToken<ITexture>* texs,
                                             const int* texBindIdx, const bool* depthBind,
                                             size_t baseVert, size_t baseInst)
{
    return {new GLShaderDataBinding(m_data, pipeline, vtxFormat, ubufCount, ubufs,
                                    ubufOffs, ubufSizes, texCount, texs, texBindIdx, depthBind)};
}

GLDataFactory::Context::Context(GLDataFactory& parent)
: m_parent(parent), m_data(new BaseGraphicsData(static_cast<GLDataFactoryImpl&>(parent)))
{}

GLDataFactory::Context::~Context() {}

void GLDataFactoryImpl::commitTransaction(const FactoryCommitFunc& trans)
{
    GLDataFactory::Context ctx(*this);
    if (!trans(ctx))
        return;

    /* Let's go ahead and flush to ensure our data gets to the GPU
       While this isn't strictly required, some drivers might behave
       differently */
    //glFlush();
}

ObjToken<IGraphicsBufferD> GLDataFactoryImpl::newPoolBuffer(BufferUse use, size_t stride, size_t count)
{
    ObjToken<BaseGraphicsPool> pool(new BaseGraphicsPool(*this));
    return {new GLGraphicsBufferD<BaseGraphicsPool>(pool, use, stride * count)};
}

static const GLint SEMANTIC_COUNT_TABLE[] =
{
    0,
    3,
    4,
    3,
    4,
    4,
    4,
    2,
    4,
    4,
    4
};

static const size_t SEMANTIC_SIZE_TABLE[] =
{
    0,
    12,
    16,
    12,
    16,
    16,
    4,
    8,
    16,
    16,
    16
};

static const GLenum SEMANTIC_TYPE_TABLE[] =
{
    GL_INVALID_ENUM,
    GL_FLOAT,
    GL_FLOAT,
    GL_FLOAT,
    GL_FLOAT,
    GL_FLOAT,
    GL_UNSIGNED_BYTE,
    GL_FLOAT,
    GL_FLOAT,
    GL_FLOAT,
    GL_FLOAT
};

struct GLCommandQueue : IGraphicsCommandQueue
{
    Platform platform() const { return IGraphicsDataFactory::Platform::OpenGL; }
    const SystemChar* platformName() const { return _S("OpenGL"); }
    IGraphicsContext* m_parent = nullptr;

    std::mutex m_mt;
    std::condition_variable m_cv;
    std::mutex m_initmt;
    std::condition_variable m_initcv;
    std::unique_lock<std::mutex> m_initlk;
    std::thread m_thr;
    
    struct Command
    {
        enum class Op
        {
            SetShaderDataBinding,
            SetRenderTarget,
            SetViewport,
            SetScissor,
            SetClearColor,
            ClearTarget,
            Draw,
            DrawIndexed,
            DrawInstances,
            DrawInstancesIndexed,
            ResolveBindTexture,
            Present
        } m_op;
        union
        {
            struct
            {
                SWindowRect rect;
                float znear, zfar;
            } viewport;
            float rgba[4];
            GLbitfield flags;
            struct
            {
                size_t start;
                size_t count;
                size_t instCount;
            };
        };
        ObjToken<IShaderDataBinding> binding;
        ObjToken<ITextureR> target;
        ObjToken<ITextureR> source;
        ObjToken<ITextureR> resolveTex;
        int bindIdx;
        bool resolveColor : 1;
        bool resolveDepth : 1;
        Command(Op op) : m_op(op) {}
        Command(const Command&) = delete;
        Command& operator=(const Command&) = delete;
        Command(Command&&) = default;
        Command& operator=(Command&&) = default;
    };
    std::vector<Command> m_cmdBufs[3];
    int m_fillBuf = 0;
    int m_completeBuf = 0;
    int m_drawBuf = 0;
    bool m_running = true;

    struct RenderTextureResize
    {
        ObjToken<ITextureR> tex;
        size_t width;
        size_t height;
    };

    /* These members are locked for multithreaded access */
    std::vector<RenderTextureResize> m_pendingResizes;
    std::vector<std::function<void(void)>> m_pendingPosts1;
    std::vector<std::function<void(void)>> m_pendingPosts2;
    std::vector<ObjToken<IVertexFormat>> m_pendingFmtAdds;
    std::vector<ObjToken<ITextureR>> m_pendingFboAdds;

    static void ConfigureVertexFormat(GLVertexFormat* fmt)
    {
        glGenVertexArrays(3, fmt->m_vao);

        size_t stride = 0;
        size_t instStride = 0;
        for (size_t i=0 ; i<fmt->m_elements.size() ; ++i)
        {
            const VertexElementDescriptor& desc = fmt->m_elements[i];
            if ((desc.semantic & VertexSemantic::Instanced) != VertexSemantic::None)
                instStride += SEMANTIC_SIZE_TABLE[int(desc.semantic & VertexSemantic::SemanticMask)];
            else
                stride += SEMANTIC_SIZE_TABLE[int(desc.semantic & VertexSemantic::SemanticMask)];
        }

        for (int b=0 ; b<3 ; ++b)
        {
            size_t offset = fmt->m_baseVert * stride;
            size_t instOffset = fmt->m_baseInst * instStride;
            glBindVertexArray(fmt->m_vao[b]);
            IGraphicsBuffer* lastVBO = nullptr;
            IGraphicsBuffer* lastEBO = nullptr;
            for (size_t i=0 ; i<fmt->m_elements.size() ; ++i)
            {
                const VertexElementDescriptor& desc = fmt->m_elements[i];
                if (desc.vertBuffer.get() != lastVBO)
                {
                    lastVBO = desc.vertBuffer.get();
                    if (lastVBO->dynamic())
                        static_cast<GLGraphicsBufferD<BaseGraphicsData>*>(lastVBO)->bindVertex(b);
                    else
                        static_cast<GLGraphicsBufferS*>(lastVBO)->bindVertex();
                }
                if (desc.indexBuffer.get() != lastEBO)
                {
                    lastEBO = desc.indexBuffer.get();
                    if (lastEBO->dynamic())
                        static_cast<GLGraphicsBufferD<BaseGraphicsData>*>(lastEBO)->bindIndex(b);
                    else
                        static_cast<GLGraphicsBufferS*>(lastEBO)->bindIndex();
                }
                glEnableVertexAttribArray(i);
                int maskedSem = int(desc.semantic & VertexSemantic::SemanticMask);
                if ((desc.semantic & VertexSemantic::Instanced) != VertexSemantic::None)
                {
                    glVertexAttribPointer(i, SEMANTIC_COUNT_TABLE[maskedSem],
                            SEMANTIC_TYPE_TABLE[maskedSem], GL_TRUE, instStride, (void*)instOffset);
                    glVertexAttribDivisor(i, 1);
                    instOffset += SEMANTIC_SIZE_TABLE[maskedSem];
                }
                else
                {
                    glVertexAttribPointer(i, SEMANTIC_COUNT_TABLE[maskedSem],
                            SEMANTIC_TYPE_TABLE[maskedSem], GL_TRUE, stride, (void*)offset);
                    offset += SEMANTIC_SIZE_TABLE[maskedSem];
                }
            }
        }
    }

    static void ConfigureFBO(GLTextureR* tex)
    {
        glGenFramebuffers(1, &tex->m_fbo);
        glBindFramebuffer(GL_FRAMEBUFFER, tex->m_fbo);
        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, tex->m_texs[0], 0);
        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, tex->m_texs[1], 0);
    }

    static void RenderingWorker(GLCommandQueue* self)
    {
        std::string thrName = APP->getFriendlyName() + " GL Rendering Thread";
        logvisor::RegisterThreadName(thrName.c_str());
        {
            std::unique_lock<std::mutex> lk(self->m_initmt);
            self->m_parent->makeCurrent();
            if (glewInit() != GLEW_OK)
                Log.report(logvisor::Fatal, "unable to init glew");
            const GLubyte* version = glGetString(GL_VERSION);
            Log.report(logvisor::Info, "OpenGL Version: %s", version);
            self->m_parent->postInit();
            glClearColor(0.f, 0.f, 0.f, 0.f);
        }
        self->m_initcv.notify_one();
        while (self->m_running)
        {
            std::vector<std::function<void(void)>> posts;
            {
                std::unique_lock<std::mutex> lk(self->m_mt);
                self->m_cv.wait(lk);
                if (!self->m_running)
                    break;
                self->m_drawBuf = self->m_completeBuf;

                glBindFramebuffer(GL_FRAMEBUFFER, 0);

                if (self->m_pendingFboAdds.size())
                {
                    for (ObjToken<ITextureR>& tex : self->m_pendingFboAdds)
                        ConfigureFBO(tex.cast<GLTextureR>());
                    self->m_pendingFboAdds.clear();
                }

                if (self->m_pendingResizes.size())
                {
                    for (const RenderTextureResize& resize : self->m_pendingResizes)
                        resize.tex.cast<GLTextureR>()->resize(resize.width, resize.height);
                    self->m_pendingResizes.clear();
                }

                if (self->m_pendingFmtAdds.size())
                {
                    for (ObjToken<IVertexFormat>& fmt : self->m_pendingFmtAdds)
                        if (fmt) ConfigureVertexFormat(fmt.cast<GLVertexFormat>());
                    self->m_pendingFmtAdds.clear();
                }

                if (self->m_pendingPosts2.size())
                    posts.swap(self->m_pendingPosts2);
            }
            std::vector<Command>& cmds = self->m_cmdBufs[self->m_drawBuf];
            GLenum currentPrim = GL_TRIANGLES;
            const GLShaderDataBinding* curBinding = nullptr;
            for (const Command& cmd : cmds)
            {
                switch (cmd.m_op)
                {
                case Command::Op::SetShaderDataBinding:
                {
                    const GLShaderDataBinding* binding = cmd.binding.cast<GLShaderDataBinding>();
                    binding->bind(self->m_drawBuf);
                    curBinding = binding;
                    currentPrim = binding->m_pipeline.cast<GLShaderPipeline>()->m_drawPrim;
                    break;
                }
                case Command::Op::SetRenderTarget:
                {
                    const GLTextureR* tex = cmd.target.cast<GLTextureR>();
                    if (!tex)
                        glBindFramebuffer(GL_FRAMEBUFFER, 0);
                    else
                        glBindFramebuffer(GL_FRAMEBUFFER, tex->m_fbo);
                    break;
                }
                case Command::Op::SetViewport:
                    glViewport(cmd.viewport.rect.location[0], cmd.viewport.rect.location[1],
                               cmd.viewport.rect.size[0], cmd.viewport.rect.size[1]);
                    glDepthRange(cmd.viewport.znear, cmd.viewport.zfar);
                    break;
                case Command::Op::SetScissor:
                    if (cmd.viewport.rect.size[0] == 0 && cmd.viewport.rect.size[1] == 0)
                        glDisable(GL_SCISSOR_TEST);
                    else
                    {
                        glEnable(GL_SCISSOR_TEST);
                        glScissor(cmd.viewport.rect.location[0], cmd.viewport.rect.location[1],
                                  cmd.viewport.rect.size[0], cmd.viewport.rect.size[1]);
                    }
                    break;
                case Command::Op::SetClearColor:
                    glClearColor(cmd.rgba[0], cmd.rgba[1], cmd.rgba[2], cmd.rgba[3]);
                    break;
                case Command::Op::ClearTarget:
                    if (cmd.flags & GL_COLOR_BUFFER_BIT)
                        glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
                    if (cmd.flags & GL_DEPTH_BUFFER_BIT)
                        glDepthMask(GL_TRUE);
                    glClear(cmd.flags);
                    break;
                case Command::Op::Draw:
                    glDrawArrays(currentPrim, cmd.start, cmd.count);
                    break;
                case Command::Op::DrawIndexed:
                    glDrawElements(currentPrim, cmd.count, GL_UNSIGNED_INT,
                                   reinterpret_cast<void*>(cmd.start * 4));
                    break;
                case Command::Op::DrawInstances:
                    glDrawArraysInstanced(currentPrim, cmd.start, cmd.count, cmd.instCount);
                    break;
                case Command::Op::DrawInstancesIndexed:
                    glDrawElementsInstanced(currentPrim, cmd.count, GL_UNSIGNED_INT,
                                            reinterpret_cast<void*>(cmd.start * 4), cmd.instCount);
                    break;
                case Command::Op::ResolveBindTexture:
                {
                    const GLTextureR* tex = cmd.resolveTex.cast<GLTextureR>();
                    GLenum target = (tex->m_samples > 1) ? GL_TEXTURE_2D_MULTISAMPLE : GL_TEXTURE_2D;
                    glBindFramebuffer(GL_READ_FRAMEBUFFER, tex->m_fbo);
                    glActiveTexture(GL_TEXTURE9);
                    if (cmd.resolveColor && tex->m_bindTexs[0][cmd.bindIdx])
                    {
                        glBindTexture(target, tex->m_bindTexs[0][cmd.bindIdx]);
                        glCopyTexSubImage2D(target, 0, cmd.viewport.rect.location[0], cmd.viewport.rect.location[1],
                                            cmd.viewport.rect.location[0], cmd.viewport.rect.location[1],
                                            cmd.viewport.rect.size[0], cmd.viewport.rect.size[1]);
                    }
                    if (cmd.resolveDepth && tex->m_bindTexs[1][cmd.bindIdx])
                    {
                        glBindTexture(target, tex->m_bindTexs[1][cmd.bindIdx]);
                        glCopyTexSubImage2D(target, 0, cmd.viewport.rect.location[0], cmd.viewport.rect.location[1],
                                            cmd.viewport.rect.location[0], cmd.viewport.rect.location[1],
                                            cmd.viewport.rect.size[0], cmd.viewport.rect.size[1]);
                    }
                    break;
                }
                case Command::Op::Present:
                {
                    if (const GLTextureR* tex = cmd.source.cast<GLTextureR>())
                    {
                        glBindFramebuffer(GL_READ_FRAMEBUFFER, tex->m_fbo);
                        glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
                        glBlitFramebuffer(0, 0, tex->m_width, tex->m_height, 0, 0,
                                          tex->m_width, tex->m_height, GL_COLOR_BUFFER_BIT, GL_NEAREST);
                    }
                    self->m_parent->present();
                    break;
                }
                default: break;
                }
            }
            for (auto& p : posts)
                p();
            cmds.clear();
        }
    }

    GLCommandQueue(IGraphicsContext* parent)
    : m_parent(parent),
      m_initlk(m_initmt),
      m_thr(RenderingWorker, this)
    {
        m_initcv.wait(m_initlk);
        m_initlk.unlock();
    }

    void stopRenderer()
    {
        if (m_running)
        {
            m_running = false;
            m_cv.notify_one();
            if (m_thr.joinable())
                m_thr.join();
            for (int i=0 ; i<3 ; ++i)
                m_cmdBufs[i].clear();
        }
    }

    ~GLCommandQueue()
    {
        stopRenderer();
    }

    void setShaderDataBinding(const ObjToken<IShaderDataBinding>& binding)
    {
        std::vector<Command>& cmds = m_cmdBufs[m_fillBuf];
        cmds.emplace_back(Command::Op::SetShaderDataBinding);
        cmds.back().binding = binding;
    }

    void setRenderTarget(const ObjToken<ITextureR>& target)
    {
        std::vector<Command>& cmds = m_cmdBufs[m_fillBuf];
        cmds.emplace_back(Command::Op::SetRenderTarget);
        cmds.back().target = target;
    }

    void setViewport(const SWindowRect& rect, float znear, float zfar)
    {
        std::vector<Command>& cmds = m_cmdBufs[m_fillBuf];
        cmds.emplace_back(Command::Op::SetViewport);
        cmds.back().viewport.rect = rect;
        cmds.back().viewport.znear = znear;
        cmds.back().viewport.zfar = zfar;
    }

    void setScissor(const SWindowRect& rect)
    {
        std::vector<Command>& cmds = m_cmdBufs[m_fillBuf];
        cmds.emplace_back(Command::Op::SetScissor);
        cmds.back().viewport.rect = rect;
    }

    void resizeRenderTexture(const ObjToken<ITextureR>& tex, size_t width, size_t height)
    {
        std::unique_lock<std::mutex> lk(m_mt);
        GLTextureR* texgl = tex.cast<GLTextureR>();
        m_pendingResizes.push_back({texgl, width, height});
    }

    void schedulePostFrameHandler(std::function<void(void)>&& func)
    {
        m_pendingPosts1.push_back(std::move(func));
    }

    void setClearColor(const float rgba[4])
    {
        std::vector<Command>& cmds = m_cmdBufs[m_fillBuf];
        cmds.emplace_back(Command::Op::SetClearColor);
        cmds.back().rgba[0] = rgba[0];
        cmds.back().rgba[1] = rgba[1];
        cmds.back().rgba[2] = rgba[2];
        cmds.back().rgba[3] = rgba[3];
    }

    void clearTarget(bool render=true, bool depth=true)
    {
        std::vector<Command>& cmds = m_cmdBufs[m_fillBuf];
        cmds.emplace_back(Command::Op::ClearTarget);
        cmds.back().flags = 0;
        if (render)
            cmds.back().flags |= GL_COLOR_BUFFER_BIT;
        if (depth)
            cmds.back().flags |= GL_DEPTH_BUFFER_BIT;
    }

    void draw(size_t start, size_t count)
    {
        std::vector<Command>& cmds = m_cmdBufs[m_fillBuf];
        cmds.emplace_back(Command::Op::Draw);
        cmds.back().start = start;
        cmds.back().count = count;
    }

    void drawIndexed(size_t start, size_t count)
    {
        std::vector<Command>& cmds = m_cmdBufs[m_fillBuf];
        cmds.emplace_back(Command::Op::DrawIndexed);
        cmds.back().start = start;
        cmds.back().count = count;
    }

    void drawInstances(size_t start, size_t count, size_t instCount)
    {
        std::vector<Command>& cmds = m_cmdBufs[m_fillBuf];
        cmds.emplace_back(Command::Op::DrawInstances);
        cmds.back().start = start;
        cmds.back().count = count;
        cmds.back().instCount = instCount;
    }

    void drawInstancesIndexed(size_t start, size_t count, size_t instCount)
    {
        std::vector<Command>& cmds = m_cmdBufs[m_fillBuf];
        cmds.emplace_back(Command::Op::DrawInstancesIndexed);
        cmds.back().start = start;
        cmds.back().count = count;
        cmds.back().instCount = instCount;
    }

    void resolveBindTexture(const ObjToken<ITextureR>& texture, const SWindowRect& rect, bool tlOrigin,
                            int bindIdx, bool color, bool depth)
    {
        GLTextureR* tex = texture.cast<GLTextureR>();
        std::vector<Command>& cmds = m_cmdBufs[m_fillBuf];
        cmds.emplace_back(Command::Op::ResolveBindTexture);
        cmds.back().resolveTex = texture;
        cmds.back().bindIdx = bindIdx;
        cmds.back().resolveColor = color;
        cmds.back().resolveDepth = depth;
        SWindowRect intersectRect = rect.intersect(SWindowRect(0, 0, tex->m_width, tex->m_height));
        SWindowRect& targetRect = cmds.back().viewport.rect;
        targetRect.location[0] = intersectRect.location[0];
        if (tlOrigin)
            targetRect.location[1] = tex->m_height - intersectRect.location[1] - intersectRect.size[1];
        else
            targetRect.location[1] = intersectRect.location[1];
        targetRect.size[0] = intersectRect.size[0];
        targetRect.size[1] = intersectRect.size[1];
    }

    void resolveDisplay(const ObjToken<ITextureR>& source)
    {
        std::vector<Command>& cmds = m_cmdBufs[m_fillBuf];
        cmds.emplace_back(Command::Op::Present);
        cmds.back().source = source;
    }

    void addVertexFormat(const ObjToken<IVertexFormat>& fmt)
    {
        std::unique_lock<std::mutex> lk(m_mt);
        m_pendingFmtAdds.push_back(fmt);
    }

    void addFBO(const ObjToken<ITextureR>& tex)
    {
        std::unique_lock<std::mutex> lk(m_mt);
        m_pendingFboAdds.push_back(tex);
    }

    void execute()
    {
        std::unique_lock<std::mutex> lk(m_mt);
        m_completeBuf = m_fillBuf;
        for (int i=0 ; i<3 ; ++i)
        {
            if (i == m_completeBuf || i == m_drawBuf)
                continue;
            m_fillBuf = i;
            break;
        }

        /* Update dynamic data here */
        GLDataFactoryImpl* gfxF = static_cast<GLDataFactoryImpl*>(m_parent->getDataFactory());
        std::unique_lock<std::mutex> datalk(gfxF->m_dataMutex);
        if (gfxF->m_dataHead)
        {
            for (BaseGraphicsData& d : *gfxF->m_dataHead)
            {
                if (d.m_DBufs)
                    for (IGraphicsBufferD& b : *d.m_DBufs)
                        static_cast<GLGraphicsBufferD<BaseGraphicsData>&>(b).update(m_completeBuf);
                if (d.m_DTexs)
                    for (ITextureD& t : *d.m_DTexs)
                        static_cast<GLTextureD&>(t).update(m_completeBuf);
            }
        }
        if (gfxF->m_poolHead)
        {
            for (BaseGraphicsPool& p : *gfxF->m_poolHead)
            {
                if (p.m_DBufs)
                    for (IGraphicsBufferD& b : *p.m_DBufs)
                        static_cast<GLGraphicsBufferD<BaseGraphicsData>&>(b).update(m_completeBuf);
            }
        }
        datalk.unlock();
        glFlush();

        for (auto& p : m_pendingPosts1)
            m_pendingPosts2.push_back(std::move(p));
        m_pendingPosts1.clear();

        lk.unlock();
        m_cv.notify_one();
        m_cmdBufs[m_fillBuf].clear();
    }
};

ObjToken<IGraphicsBufferD>
GLDataFactory::Context::newDynamicBuffer(BufferUse use, size_t stride, size_t count)
{
    return {new GLGraphicsBufferD<BaseGraphicsData>(m_data, use, stride * count)};
}

ObjToken<ITextureD>
GLDataFactory::Context::newDynamicTexture(size_t width, size_t height, TextureFormat fmt, TextureClampMode clampMode)
{
    return {new GLTextureD(m_data, width, height, fmt, clampMode)};
}

GLTextureR::GLTextureR(const ObjToken<BaseGraphicsData>& parent, GLCommandQueue* q, size_t width, size_t height,
                       size_t samples, TextureClampMode clampMode, size_t colorBindingCount, size_t depthBindingCount)
: GraphicsDataNode<ITextureR>(parent), m_q(q), m_width(width), m_height(height), m_samples(samples)
{
    glGenTextures(2, m_texs);
    if (colorBindingCount)
    {
        if (colorBindingCount > MAX_BIND_TEXS)
            Log.report(logvisor::Fatal, "too many color bindings for render texture");
        glGenTextures(colorBindingCount, m_bindTexs[0]);
    }
    if (depthBindingCount)
    {
        if (depthBindingCount > MAX_BIND_TEXS)
            Log.report(logvisor::Fatal, "too many depth bindings for render texture");
        glGenTextures(depthBindingCount, m_bindTexs[1]);
    }

    if (samples > 1)
    {
        m_target = GL_TEXTURE_2D_MULTISAMPLE;
        glBindTexture(GL_TEXTURE_2D_MULTISAMPLE, m_texs[0]);
        glTexImage2DMultisample(GL_TEXTURE_2D_MULTISAMPLE, samples, GL_RGBA, width, height, GL_FALSE);
        glBindTexture(GL_TEXTURE_2D_MULTISAMPLE, m_texs[1]);
        glTexImage2DMultisample(GL_TEXTURE_2D_MULTISAMPLE, samples, GL_DEPTH_COMPONENT24, width, height, GL_FALSE);
    }
    else
    {
        m_target = GL_TEXTURE_2D;
        glBindTexture(GL_TEXTURE_2D, m_texs[0]);
        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
        glBindTexture(GL_TEXTURE_2D, m_texs[1]);
        glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT24, width, height, 0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, nullptr);
    }

    for (int i=0 ; i<colorBindingCount ; ++i)
    {
        glBindTexture(GL_TEXTURE_2D, m_bindTexs[0][i]);
        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        SetClampMode(GL_TEXTURE_2D, clampMode);
    }
    for (int i=0 ; i<depthBindingCount ; ++i)
    {
        glBindTexture(GL_TEXTURE_2D, m_bindTexs[1][i]);
        glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT24, width, height, 0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, nullptr);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        SetClampMode(GL_TEXTURE_2D, clampMode);
    }

    m_q->addFBO(this);
}

ObjToken<ITextureR>
GLDataFactory::Context::newRenderTexture(size_t width, size_t height, TextureClampMode clampMode,
                                         size_t colorBindingCount, size_t depthBindingCount)
{
    GLDataFactoryImpl& factory = static_cast<GLDataFactoryImpl&>(m_parent);
    GLCommandQueue* q = static_cast<GLCommandQueue*>(factory.m_parent->getCommandQueue());
    ObjToken<ITextureR> retval(new GLTextureR(m_data, q, width, height, factory.m_drawSamples, clampMode,
                                              colorBindingCount, depthBindingCount));
    q->resizeRenderTexture(retval, width, height);
    return retval;
}

GLVertexFormat::GLVertexFormat(const ObjToken<BaseGraphicsData>& parent, GLCommandQueue* q,
                               size_t elementCount, const VertexElementDescriptor* elements,
                               size_t baseVert, size_t baseInst)
: GraphicsDataNode<IVertexFormat>(parent),
  m_baseVert(baseVert), m_baseInst(baseInst)
{
    m_elements.reserve(elementCount);
    for (size_t i=0 ; i<elementCount ; ++i)
        m_elements.push_back(elements[i]);
    q->addVertexFormat(this);
}

ObjToken<IVertexFormat> GLDataFactory::Context::newVertexFormat
(size_t elementCount, const VertexElementDescriptor* elements,
 size_t baseVert, size_t baseInst)
{
    GLDataFactoryImpl& factory = static_cast<GLDataFactoryImpl&>(m_parent);
    GLCommandQueue* q = static_cast<GLCommandQueue*>(factory.m_parent->getCommandQueue());
    return {new GLVertexFormat(m_data, q, elementCount, elements, baseVert, baseInst)};
}

IGraphicsCommandQueue* _NewGLCommandQueue(IGraphicsContext* parent)
{
    return new struct GLCommandQueue(parent);
}

IGraphicsDataFactory* _NewGLDataFactory(IGraphicsContext* parent, uint32_t drawSamples)
{
    return new class GLDataFactoryImpl(parent, drawSamples);
}

}