#pragma once
#include <SDL_video.h>

#include "imgui.h"
#include "slang_handle.h"

class shader;
class render_target;
class texture;
constexpr ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f);
constexpr float clear_color_with_alpha[4] = { clear_color.x * clear_color.w, clear_color.y * clear_color.w, clear_color.z * clear_color.w, clear_color.w };

class renderer
{
public:
    virtual ~renderer() = default;
    virtual void pre_init() {}
    virtual bool init(SDL_Window* window_handle) = 0;
    virtual void shutdown() = 0;

    void init_slang(const std::string& shader_path);
    virtual Slang::ComPtr<slang::ISession> create_slang_session(const std::string& shader_path) = 0;
    virtual Slang::ComPtr<slang::ISession> get_slang_session() { return session_; }
    virtual std::shared_ptr<shader> load_shader(const std::string& entry_name) = 0;
    virtual std::shared_ptr<shader> get_pixel_shader_render_default_vs();
    
    virtual void new_frame(SDL_Window* window_handle) = 0;
    virtual void end_frame(SDL_Window* window_handle) = 0;

    virtual void resize(int width, int height) = 0;
    virtual std::shared_ptr<texture> create_texture(const unsigned char* data, int width, int height) = 0;
    virtual std::shared_ptr<render_target> create_render_target(int width, int height, texture_format format) = 0;
    
    void set_vsync(const bool vsync) { vsync_ = vsync; }
protected:
    Slang::ComPtr<slang::ISession> session_;
    std::shared_ptr<shader> default_vs_;
    bool vsync_ = true;
};