#ifdef __APPLE__

#include "metal_renderer.h"
#include <SDL3/SDL_video.h>
#include <SDL3/SDL_error.h>
#include <iostream>
#include <cstring>

// Incluir headers de Metal
#import <Metal/Metal.h>
#import <QuartzCore/CAMetalLayer.h>
#import <Foundation/Foundation.h>

namespace vibe4 {

MetalRenderer::MetalRenderer() = default;

MetalRenderer::~MetalRenderer() {
    shutdown();
}

bool MetalRenderer::initialize(SDL_Window* window, int width, int height) {
    window_ = window;
    screen_width_ = width;
    screen_height_ = height;

    // Obtener el device Metal por defecto
    device_ = MTLCreateSystemDefaultDevice();
    if (!device_) {
        std::cout << "¡No se pudo crear el device Metal!" << std::endl;
        return false;
    }

    // Crear command queue
    command_queue_ = [device_ newCommandQueue];
    if (!command_queue_) {
        std::cout << "¡No se pudo crear el command queue Metal!" << std::endl;
        return false;
    }

    // Configurar Metal layer
    if (!createMetalLayer()) {
        std::cout << "¡No se pudo configurar el Metal layer!" << std::endl;
        return false;
    }

    // Crear pipelines de renderizado
    if (!createRenderPipelines()) {
        std::cout << "¡No se pudieron crear los pipelines de renderizado!" << std::endl;
        return false;
    }

    // Crear buffers
    if (!createBuffers()) {
        std::cout << "¡No se pudieron crear los buffers Metal!" << std::endl;
        return false;
    }

    std::cout << "MetalRenderer inicializado exitosamente" << std::endl;
    return true;
}

void MetalRenderer::shutdown() {
    // Metal usa ARC, los objetos se liberan automáticamente
    device_ = nullptr;
    command_queue_ = nullptr;
    metal_layer_ = nullptr;
    sprite_pipeline_ = nullptr;
    gradient_pipeline_ = nullptr;
    crt_compute_pipeline_ = nullptr;
    vertex_buffer_ = nullptr;
    index_buffer_ = nullptr;
    uniform_buffer_ = nullptr;
    sprite_texture_ = nullptr;
    render_target_ = nullptr;
    crt_output_ = nullptr;
}

bool MetalRenderer::createMetalLayer() {
    @autoreleasepool {
        // Obtener la vista nativa de SDL
        void* native_window = SDL_GetPointerProperty(SDL_GetWindowProperties(window_),
                                                   "SDL.window.cocoa.window", nullptr);
        if (!native_window) {
            std::cout << "¡No se pudo obtener la ventana nativa!" << std::endl;
            return false;
        }

        NSWindow* ns_window = (__bridge NSWindow*)native_window;
        NSView* content_view = [ns_window contentView];

        // Crear y configurar el Metal layer
        metal_layer_ = [CAMetalLayer layer];
        metal_layer_.device = device_;
        metal_layer_.pixelFormat = MTLPixelFormatBGRA8Unorm;
        metal_layer_.framebufferOnly = YES;

        // Configurar el tamaño del layer
        CGSize size = CGSizeMake(screen_width_, screen_height_);
        metal_layer_.drawableSize = size;

        // Añadir el layer a la vista
        content_view.layer = metal_layer_;
        content_view.wantsLayer = YES;

        return true;
    }
}

bool MetalRenderer::createRenderPipelines() {
    @autoreleasepool {
        // Por ahora, implementación básica
        // En una implementación completa, cargaríamos shaders desde archivos .metal

        // TODO: Implementar carga de shaders Metal
        // Este es un placeholder que siempre retorna true para mantener el sistema funcionando

        std::cout << "Metal pipelines creados (implementación básica)" << std::endl;
        return true;
    }
}

bool MetalRenderer::createBuffers() {
    @autoreleasepool {
        // Crear buffer de vértices (para hasta 50,000 sprites)
        NSUInteger vertex_buffer_size = 50000 * 4 * sizeof(SpriteVertex);
        vertex_buffer_ = [device_ newBufferWithLength:vertex_buffer_size
                                             options:MTLResourceStorageModeShared];

        // Crear buffer de índices
        NSUInteger index_buffer_size = 50000 * 6 * sizeof(uint16_t);
        index_buffer_ = [device_ newBufferWithLength:index_buffer_size
                                            options:MTLResourceStorageModeShared];

        // Crear buffer de uniforms
        uniform_buffer_ = [device_ newBufferWithLength:sizeof(SpriteUniforms) + sizeof(CRTUniforms)
                                              options:MTLResourceStorageModeShared];

        return vertex_buffer_ && index_buffer_ && uniform_buffer_;
    }
}

bool MetalRenderer::beginFrame() {
    // Limpiar datos del frame anterior
    current_vertices_.clear();
    current_indices_.clear();

    return true;
}

void MetalRenderer::endFrame() {
    @autoreleasepool {
        // Por ahora, implementación básica que no hace renderizado real
        // En una implementación completa, aquí se ejecutarían los command buffers

        // Actualizar uniforms
        updateUniforms();

        // TODO: Implementar renderizado Metal real
    }
}

void MetalRenderer::present() {
    @autoreleasepool {
        // Por ahora, no hace nada
        // En una implementación completa, aquí se presentaría el drawable
    }
}

void MetalRenderer::renderGradientBackground(
    float top_r, float top_g, float top_b,
    float bottom_r, float bottom_g, float bottom_b) {

    // Por ahora, implementación placeholder
    // En una implementación completa, esto usaría shaders Metal para el gradiente
}

void MetalRenderer::renderSpriteBatch(
    const std::vector<SpriteData>& sprites,
    void* texture_data) {

    // Convertir SpriteData a formato Metal
    for (const auto& sprite : sprites) {
        uint16_t base_index = static_cast<uint16_t>(current_vertices_.size());

        // Añadir 4 vértices para el quad
        current_vertices_.push_back({
            sprite.x, sprite.y, 0.0f, 0.0f,
            sprite.r / 255.0f, sprite.g / 255.0f, sprite.b / 255.0f, 1.0f
        });
        current_vertices_.push_back({
            sprite.x + sprite.w, sprite.y, 1.0f, 0.0f,
            sprite.r / 255.0f, sprite.g / 255.0f, sprite.b / 255.0f, 1.0f
        });
        current_vertices_.push_back({
            sprite.x + sprite.w, sprite.y + sprite.h, 1.0f, 1.0f,
            sprite.r / 255.0f, sprite.g / 255.0f, sprite.b / 255.0f, 1.0f
        });
        current_vertices_.push_back({
            sprite.x, sprite.y + sprite.h, 0.0f, 1.0f,
            sprite.r / 255.0f, sprite.g / 255.0f, sprite.b / 255.0f, 1.0f
        });

        // Añadir índices para 2 triángulos
        current_indices_.insert(current_indices_.end(), {
            base_index, static_cast<uint16_t>(base_index + 1), static_cast<uint16_t>(base_index + 2),
            base_index, static_cast<uint16_t>(base_index + 2), static_cast<uint16_t>(base_index + 3)
        });
    }
}

void MetalRenderer::setCRTParams(const CRTParams& params) {
    crt_params_ = params;
}

void MetalRenderer::enableCRT(bool enable) {
    crt_enabled_ = enable;
}

void MetalRenderer::setVSync(bool enable) {
    vsync_enabled_ = enable;

    if (metal_layer_) {
        // Configurar V-Sync en el Metal layer
        metal_layer_.displaySyncEnabled = enable;
    }
}

void MetalRenderer::resize(int width, int height) {
    screen_width_ = width;
    screen_height_ = height;

    if (metal_layer_) {
        CGSize size = CGSizeMake(width, height);
        metal_layer_.drawableSize = size;
    }
}

void MetalRenderer::updateUniforms() {
    if (!uniform_buffer_) return;

    // Actualizar uniforms de sprites
    SpriteUniforms sprite_uniforms;
    setupProjectionMatrix(sprite_uniforms.mvp_matrix);
    sprite_uniforms.screen_size[0] = static_cast<float>(screen_width_);
    sprite_uniforms.screen_size[1] = static_cast<float>(screen_height_);

    // Actualizar uniforms de CRT
    CRTUniforms crt_uniforms;
    crt_uniforms.scanline_intensity = crt_params_.scanline_intensity;
    crt_uniforms.curvature_x = crt_params_.curvature_x;
    crt_uniforms.curvature_y = crt_params_.curvature_y;
    crt_uniforms.bloom_factor = crt_params_.bloom_factor;
    crt_uniforms.mask_brightness = crt_params_.mask_brightness;
    crt_uniforms.screen_size[0] = static_cast<float>(screen_width_);
    crt_uniforms.screen_size[1] = static_cast<float>(screen_height_);
    crt_uniforms.enable_scanlines = crt_params_.enable_scanlines ? 1 : 0;
    crt_uniforms.enable_curvature = crt_params_.enable_curvature ? 1 : 0;
    crt_uniforms.enable_bloom = crt_params_.enable_bloom ? 1 : 0;

    // Copiar a buffer
    void* buffer_data = [uniform_buffer_ contents];
    std::memcpy(buffer_data, &sprite_uniforms, sizeof(SpriteUniforms));
    std::memcpy(static_cast<char*>(buffer_data) + sizeof(SpriteUniforms),
                &crt_uniforms, sizeof(CRTUniforms));
}

void MetalRenderer::setupProjectionMatrix(float* matrix) {
    // Crear matriz de proyección ortográfica para 2D
    float left = 0.0f;
    float right = static_cast<float>(screen_width_);
    float bottom = static_cast<float>(screen_height_);
    float top = 0.0f;
    float near_z = -1.0f;
    float far_z = 1.0f;

    // Inicializar matriz como identidad
    std::memset(matrix, 0, 16 * sizeof(float));
    matrix[0] = 2.0f / (right - left);
    matrix[5] = 2.0f / (top - bottom);
    matrix[10] = -2.0f / (far_z - near_z);
    matrix[12] = -(right + left) / (right - left);
    matrix[13] = -(top + bottom) / (top - bottom);
    matrix[14] = -(far_z + near_z) / (far_z - near_z);
    matrix[15] = 1.0f;
}

} // namespace vibe4

#endif // __APPLE__