#pragma once

#include <SDL3/SDL_gpu.h>
#include <map>
#include <memory>
#include <string>
#include <vector>

#include "gpu_shader_preset.hpp"

// ============================================================================
// ShaderManager — discovers and manages runtime shader presets under
// a root directory (e.g., data/shaders/).
//
// Each subdirectory with a preset.ini is treated as a shader preset.
// ============================================================================
class ShaderManager {
public:
    // Scan root_dir for preset subdirectories (each must contain preset.ini).
    void scan(const std::string& root_dir);

    // Available preset names (e.g. {"ntsc-md-rainbows"}).
    const std::vector<std::string>& names() const { return names_; }

    // Load and return a preset (cached). Returns null on failure.
    GpuShaderPreset* load(SDL_GPUDevice* device,
                          const std::string& name,
                          SDL_GPUTextureFormat swapchain_fmt,
                          int w, int h);

    // Recreate intermediate render targets on resolution change.
    void onResize(SDL_GPUDevice* device, SDL_GPUTextureFormat swapchain_fmt, int w, int h);

    void destroyAll(SDL_GPUDevice* device);

private:
    std::string              root_dir_;
    std::vector<std::string> names_;
    std::map<std::string, std::string>                   dirs_;
    std::map<std::string, std::unique_ptr<GpuShaderPreset>> loaded_;
};