export default defineContentScript({
  matches: ["<all_urls>"],
  runAt: "document_idle", // 确保在页面加载完成后运行
  
  main(ctx) {
    console.log('Content script loaded on:', window.location.href);
    
    // 监听来自popup的消息
    const handleMessage = (request: any, sender: any, sendResponse: any) => {
      console.log('Received message:', request);
      
      // 处理测试消息
      if (request.action === "test") {
        sendResponse({ status: "success", message: "Content script is running" });
        return true;
      }
      
      if (request.action === "getImages") {
        try {
          // 获取页面上所有图片元素
          const imageElements = Array.from(document.querySelectorAll('img'));
          
          // 获取背景图片元素
          const allElements = Array.from(document.querySelectorAll('*'));
          const backgroundImages: Array<{url: string, element: string, class: string, id: string}> = [];
          
          // 提取<img>标签的图片
          const imgSources = imageElements
            .map(img => {
              let url = img.src;
              // 处理相对路径
              if (url && !url.startsWith('http') && !url.startsWith('data:')) {
                try {
                  url = new URL(url, window.location.origin).href;
                } catch (e) {
                  console.warn('Failed to resolve relative URL:', url);
                }
              }
              return {
                url,
                element: 'img',
                class: img.className || '',
                id: img.id || '',
                alt: img.alt || ''
              };
            })
            .filter(img => img.url && (img.url.startsWith('http') || img.url.startsWith('data:')));
          
          // 提取背景图片
          allElements.forEach(element => {
            const computedStyle = window.getComputedStyle(element);
            const backgroundImage = computedStyle.backgroundImage;
            
            // 检查是否有background-image
            if (backgroundImage && backgroundImage !== 'none' && backgroundImage.includes('url')) {
              // 提取URL
              const urlMatch = backgroundImage.match(/url\(["']?(.*?)["']?\)/);
              if (urlMatch && urlMatch[1]) {
                // 解码HTML实体
                const textarea = document.createElement('textarea');
                textarea.innerHTML = urlMatch[1];
                const decodedUrl = textarea.value;
                
                backgroundImages.push({
                  url: decodedUrl,
                  element: element.tagName.toLowerCase(),
                  class: element.className || '',
                  id: element.id || ''
                });
              }
            }
          });
          
          // 合并所有图片
          const allImages = [...imgSources, ...backgroundImages];
          
          console.log('Found images:', allImages);
          sendResponse({ images: allImages });
        } catch (error: any) {
          console.error('Error extracting images:', error);
          sendResponse({ images: [], error: error.message });
        }
        return true; // 保持消息通道开放
      }
    };
    
    // 添加消息监听器
    browser.runtime.onMessage.addListener(handleMessage);
    
    // 清理函数
    ctx.onInvalidated(() => {
      browser.runtime.onMessage.removeListener(handleMessage);
    });
  }
});