Extra2D/Extra2D/include/extra2d/render/backends/opengl/gl_rhi_texture.h

#pragma once

#include <extra2d/render/rhi/rhi_texture.h>
#include <glad/glad.h>
#include <string>

namespace extra2d {
namespace rhi {

/**
 * @brief OpenGL 纹理实现
 * 
 * 使用 OpenGL 4.5 DSA 特性
 */
class GLRHITexture : public RHITexture {
public:
    /**
     * @brief 构造函数
     */
    GLRHITexture();

    /**
     * @brief 析构函数
     */
    ~GLRHITexture() override;

    /**
     * @brief 初始化纹理
     * @param desc 纹理描述
     * @return 成功返回 true
     */
    bool init(const TextureDesc& desc);

    /**
     * @brief 释放资源
     */
    void shutdown();

    // RHITexture 接口实现
    TextureType getType() const override { return type_; }
    Format getFormat() const override { return format_; }
    uint32_t getWidth() const override { return width_; }
    uint32_t getHeight() const override { return height_; }
    uint32_t getDepth() const override { return depth_; }
    uint32_t getMipLevels() const override { return mipLevels_; }
    uint32_t getArrayLayers() const override { return arrayLayers_; }
    uint32_t getSampleCount() const override { return sampleCount_; }
    void setData(const void* data, uint32_t mipLevel = 0, uint32_t arrayLayer = 0) override;
    void setSubData(const void* data, uint32_t x, uint32_t y, 
                    uint32_t width, uint32_t height, uint32_t mipLevel = 0) override;
    void generateMipmaps() override;
    bool isValid() const override { return textureID_ != 0; }
    uintptr_t getNativeHandle() const override { return static_cast<uintptr_t>(textureID_); }
    const std::string& getDebugName() const override { return debugName_; }
    void setDebugName(const std::string& name) override { debugName_ = name; }

    /**
     * @brief 获取 OpenGL 纹理 ID
     */
    GLuint getTextureID() const { return textureID_; }

    /**
     * @brief 绑定到纹理单元
     */
    void bind(uint32_t unit);

    /**
     * @brief 转换纹理类型到 OpenGL 目标
     */
    static GLenum convertType(TextureType type);

    /**
     * @brief 转换格式到 OpenGL 内部格式
     */
    static GLenum convertInternalFormat(Format format);

    /**
     * @brief 转换格式到 OpenGL 格式
     */
    static GLenum convertFormat(Format format);

    /**
     * @brief 转换格式到 OpenGL 类型
     */
    static GLenum convertDataType(Format format);

    /**
     * @brief 计算格式字节大小
     */
    static uint32_t getFormatBytes(Format format);

private:
    GLuint textureID_ = 0;
    TextureType type_ = TextureType::Texture2D;
    Format format_ = Format::RGBA8_UNORM;
    uint32_t width_ = 0;
    uint32_t height_ = 0;
    uint32_t depth_ = 1;
    uint32_t mipLevels_ = 1;
    uint32_t arrayLayers_ = 1;
    uint32_t sampleCount_ = 1;
    std::string debugName_;
};

/**
 * @brief OpenGL 采样器实现
 */
class GLRHISampler : public RHISampler {
public:
    /**
     * @brief 构造函数
     */
    GLRHISampler();

    /**
     * @brief 析构函数
     */
    ~GLRHISampler() override;

    /**
     * @brief 初始化采样器
     * @param desc 采样器描述
     * @return 成功返回 true
     */
    bool init(const SamplerDesc& desc);

    /**
     * @brief 释放资源
     */
    void shutdown();

    // RHISampler 接口实现
    FilterMode getMinFilter() const override { return minFilter_; }
    FilterMode getMagFilter() const override { return magFilter_; }
    FilterMode getMipFilter() const override { return mipFilter_; }
    AddressMode getAddressModeU() const override { return addressU_; }
    AddressMode getAddressModeV() const override { return addressV_; }
    AddressMode getAddressModeW() const override { return addressW_; }
    float getMaxAnisotropy() const override { return maxAnisotropy_; }
    ColorValue getBorderColor() const override { return borderColor_; }
    bool isValid() const override { return samplerID_ != 0; }
    uintptr_t getNativeHandle() const override { return static_cast<uintptr_t>(samplerID_); }
    const std::string& getDebugName() const override { return debugName_; }
    void setDebugName(const std::string& name) override { debugName_ = name; }

    /**
     * @brief 获取 OpenGL 采样器 ID
     */
    GLuint getSamplerID() const { return samplerID_; }

    /**
     * @brief 绑定到纹理单元
     */
    void bind(uint32_t unit);

private:
    GLuint samplerID_ = 0;
    FilterMode minFilter_ = FilterMode::Linear;
    FilterMode magFilter_ = FilterMode::Linear;
    FilterMode mipFilter_ = FilterMode::LinearMipmapLinear;
    AddressMode addressU_ = AddressMode::ClampToEdge;
    AddressMode addressV_ = AddressMode::ClampToEdge;
    AddressMode addressW_ = AddressMode::ClampToEdge;
    float maxAnisotropy_ = 1.0f;
    ColorValue borderColor_;
    std::string debugName_;

    /**
     * @brief 转换过滤模式到 OpenGL 枚举
     */
    static GLenum convertFilter(FilterMode filter, FilterMode mipFilter);

    /**
     * @brief 转换寻址模式到 OpenGL 枚举
     */
    static GLenum convertAddressMode(AddressMode mode);

    /**
     * @brief 转换比较函数到 OpenGL 枚举
     */
    static GLenum convertCompareFunc(CompareFunc func);
};

/**
 * @brief OpenGL 纹理视图实现
 */
class GLRHITextureView : public RHITextureView {
public:
    /**
     * @brief 构造函数
     */
    GLRHITextureView();

    /**
     * @brief 析构函数
     */
    ~GLRHITextureView() override;

    /**
     * @brief 初始化纹理视图
     */
    bool init(Ptr<RHITexture> texture, const TextureViewDesc& desc);

    /**
     * @brief 释放资源
     */
    void shutdown();

    // RHITextureView 接口实现
    Ptr<RHITexture> getTexture() const override { return texture_; }
    Format getFormat() const override { return format_; }
    uint32_t getBaseMipLevel() const override { return baseMipLevel_; }
    uint32_t getMipLevels() const override { return mipLevels_; }
    uint32_t getBaseArrayLayer() const override { return baseArrayLayer_; }
    uint32_t getArrayLayers() const override { return arrayLayers_; }
    bool isValid() const override { return viewID_ != 0; }
    uintptr_t getNativeHandle() const override { return static_cast<uintptr_t>(viewID_); }

    /**
     * @brief 获取 OpenGL 纹理视图 ID
     */
    GLuint getViewID() const { return viewID_; }

private:
    GLuint viewID_ = 0;
    Ptr<RHITexture> texture_;
    Format format_ = Format::RGBA8_UNORM;
    uint32_t baseMipLevel_ = 0;
    uint32_t mipLevels_ = 1;
    uint32_t baseArrayLayer_ = 0;
    uint32_t arrayLayers_ = 1;
};

} // namespace rhi
} // namespace extra2d