/**
 * @file main.cpp
 * @brief Extra2D 图片显示示例
 *
 * 演示如何使用 RenderBackend 抽象接口加载和显示图片
 * 此示例不依赖任何特定渲染后端（如 OpenGL）
 */

#include <extra2d/core/service_locator.h>
#include <extra2d/extra2d.h>
#include <extra2d/graphics/core/render_backend.h>
#include <extra2d/graphics/core/render_module.h>
#include <extra2d/graphics/texture/texture.h>
#include <extra2d/platform/input_module.h>
#include <extra2d/platform/window_module.h>
#include <extra2d/services/camera_service.h>
#include <extra2d/services/event_service.h>
#include <iostream>

using namespace extra2d;

class ImageDisplayScene : public Scene {
public:
    void onEnter() override {
        // 加载图片
        // 注意：请确保有图片文件在 assets/images/ 目录下
        try {
            texture_ = renderer_->loadTexture("assets/images/demo.jpg");
            std::cout << "Image loaded successfully!" << std::endl;
            std::cout << "  Size: " << texture_->getWidth() << "x" << texture_->getHeight() << std::endl;
        } catch (...) {
            std::cerr << "Failed to load image from assets/images/demo.jpg" << std::endl;
            // 尝试使用备用路径
            try {
                texture_ = renderer_->loadTexture("examples/image_display/assets/images/demo.jpg");
                std::cout << "Image loaded from alternate path!" << std::endl;
            } catch (...) {
                std::cerr << "Failed to load image from alternate path!" << std::endl;
                texture_ = nullptr;
            }
        }
    }

    void onExit() override {
        texture_.reset();
    }

    void onRender(RenderBackend& renderer) override {
        Scene::onRender(renderer);

        if (!texture_) {
            return;
        }

        // 使用 RenderBackend 的抽象接口绘制图片
    // 不依赖任何特定后端（如 OpenGL）
    // 自动批处理：无需手动调用 begin/endSpriteBatch

    // 计算图片显示位置（居中显示）
    float windowWidth = 1280.0f;
    float windowHeight = 720.0f;
    float imgWidth = static_cast<float>(texture_->getWidth());
    float imgHeight = static_cast<float>(texture_->getHeight());

    // 缩放图片以适应窗口（保持宽高比）
    float scale = 1.0f;
    if (imgWidth > windowWidth * 0.8f || imgHeight > windowHeight * 0.8f) {
      float scaleX = (windowWidth * 0.8f) / imgWidth;
      float scaleY = (windowHeight * 0.8f) / imgHeight;
      scale = std::min(scaleX, scaleY);
    }

    float displayWidth = imgWidth * scale;
    float displayHeight = imgHeight * scale;
    float x = (windowWidth - displayWidth) * 0.5f;
    float y = (windowHeight - displayHeight) * 0.5f;

    // 使用 RenderBackend 的 drawSprite 方法绘制图片
    // 参数：纹理、目标矩形、源矩形、颜色、旋转角度、锚点
    Rect destRect(x, y, displayWidth, displayHeight);
    Rect srcRect(0, 0, imgWidth, imgHeight);
    renderer.drawSprite(*texture_, destRect, srcRect, Colors::White, 0.0f, Vec2(0, 0));

    // 注意：无需手动调用 renderer.endSpriteBatch()，帧结束时会自动刷新
    }

    void setRenderer(RenderBackend* renderer) {
        renderer_ = renderer;
    }

private:
    Ptr<Texture> texture_;
    RenderBackend* renderer_ = nullptr;
};

int main(int argc, char* argv[]) {
    (void)argc;
    (void)argv;

    std::cout << "Extra2D Image Display Demo - Starting..." << std::endl;

    Application& app = Application::get();

    // 注册模块
    app.use<WindowModule>([](auto& cfg) {
        cfg.w = 1280;
        cfg.h = 720;
        cfg.title = "Extra2D Image Display Demo";
        cfg.priority = 0;
        cfg.backend = "glfw";
    });

    app.use<RenderModule>([](auto& cfg) { cfg.priority = 10; });

    app.use<InputModule>([](auto& cfg) { cfg.priority = 20; });

    std::cout << "Initializing application..." << std::endl;
    if (!app.init()) {
        std::cerr << "Failed to initialize application!" << std::endl;
        return -1;
    }

    std::cout << "Application initialized successfully!" << std::endl;

    auto* win = app.window();
    if (win) {
        std::cout << "Window: " << win->width() << "x" << win->height() << std::endl;
    }

    // 设置事件监听
    auto eventService = ServiceLocator::instance().getService<IEventService>();
    if (eventService) {
        eventService->addListener(EventType::KeyPressed, [](Event& e) {
            auto& keyEvent = std::get<KeyEvent>(e.data);
            if (keyEvent.keyCode == static_cast<int>(Key::Escape)) {
                e.handled = true;
                Application::get().quit();
            }
        });
    }

    // 获取渲染器
  RenderBackend* renderer = app.renderer();

  // 创建并配置场景
  auto scene = makeShared<ImageDisplayScene>();
  scene->setRenderer(renderer);
    scene->setBackgroundColor(Color(0.1f, 0.1f, 0.15f, 1.0f));

    if (win) {
        scene->setViewportSize(static_cast<float>(win->width()),
                               static_cast<float>(win->height()));
    }

    // 配置相机
    auto cameraService = ServiceLocator::instance().getService<ICameraService>();
    if (cameraService && win) {
        ViewportConfig vpConfig;
        vpConfig.logicWidth = static_cast<float>(win->width());
        vpConfig.logicHeight = static_cast<float>(win->height());
        vpConfig.mode = ViewportMode::AspectRatio;
        cameraService->setViewportConfig(vpConfig);
        cameraService->updateViewport(win->width(), win->height());
        cameraService->applyViewportAdapter();
    }

    app.enterScene(scene);

    std::cout << "\nControls:" << std::endl;
    std::cout << "  ESC - Exit" << std::endl;
    std::cout << "\nRunning main loop...\n" << std::endl;

    app.run();

    std::cout << "Shutting down..." << std::endl;
    app.shutdown();

    std::cout << "Goodbye!" << std::endl;
    return 0;
}