#pragma once

#include "../Pipeline.hpp"
#include <functional>
#include <memory>
#include <GL/gl3w.h>
#include "pass/WorldProgram.hpp"
#include "pass/EntityProgram.hpp"
#include "pass/SkyProgram.hpp"
#include "pass/ColorProgram.hpp"
#include "buffer/Colored.hpp"

namespace render::gl {

/// Handle OpenGL rendering passes and params
class Pipeline final: public render::Pipeline {
public:
    Pipeline(const options&);
    Pipeline(Pipeline &&) = delete;
    Pipeline(const Pipeline &) = delete;
    Pipeline &operator=(Pipeline &&) = delete;
    Pipeline &operator=(const Pipeline &) = delete;
    ~Pipeline();

    glm::vec3 LightInvDir = glm::vec3(0.5f, 2, 2);
    glm::vec3 FogColor;
    GLfloat FogDepth;

    /// Sphere bending
    /// offset.xyz radius.w
    glm::vec4 SphereProj;
    /// Ratio between spherical and cartesian
    float Curvature;

    bool SkyEnable;

    glm::mat4 getProjectionMatrix() const {
        return ProjectionMatrix;
    }
    glm::mat4 getViewMatrix() const {
        return ViewMatrix;
    }

    GLuint getTextureAtlas() const {
        return TextureAtlas;
    }
    GLuint getNormalAtlas() const {
        return NormalAtlas;
    }
    GLuint getHOSAtlas() const {
        return HOSAtlas;
    }
    GLuint getSkyTexture() const {
        return Skybox;
    }

    /// Start new frame and setup
    void beginFrame() override;
    /// Get started world program
    std::function<buffer::params(glm::mat4)> beginWorldPass();
    /// Get started entity program
    std::function<buffer::params(const std::vector<glm::mat4>&)> beginEntityPass();
    /// Draw cube indicator
    size_t drawIndicatorCube(glm::mat4 model);
    /// Apply postprocessing
    void endPass() override;
    void swapBuffer(GLFWwindow *) override;

    void setClearColor(glm::vec4) override;

    /// Apply camera matrices
    void lookFrom(const Camera&) override;
    void reloadShaders(const pass::VoxelProgram::options &);
    void reloadTextures(const std::string &, float mipMapLOD, float anisotropy);

private:
    GLuint VertexArrayID;

    std::unique_ptr<pass::WorldProgram> WorldPass;
    std::unique_ptr<pass::EntityProgram> EntityPass;
    std::unique_ptr<pass::SkyProgram> SkyPass;
    std::unique_ptr<pass::ColorProgram> IndicatorPass;
    buffer::Colored IndicatorCubeBuffer;

    glm::mat4 ProjectionMatrix;
    glm::mat4 ViewMatrix;

    GLuint TextureAtlas;
    GLuint NormalAtlas;
    GLuint HOSAtlas;
    GLuint Skybox;

    void loadTextures(const std::string &, float mipMapLOD, float anisotropy);
    void unloadTextures();
};

}