feat: 实现批量下载功能

entrypoints/background.ts

@@ -1,3 +1,88 @@
 export default defineBackground(() => {
   console.log('Hello background!', { id: browser.runtime.id });
+
+  // 监听下载请求
+  browser.runtime.onMessage.addListener(async (msg) => {
+    if (msg.type === 'DOWNLOAD_PINS') {
+      const pins: PinData[] = msg.pins;
+      const concurrency: number = msg.concurrency || 3;
+      const result = await startBatchDownload(pins, concurrency);
+      // 通知 popup 下载完成
+      browser.runtime.sendMessage({
+        type: 'DOWNLOAD_DONE',
+        success: result.success,
+        failed: result.failed,
+        total: result.total,
       });
+    }
+  });
+});
+
+// 定义单个下载任务 (封装成 Promise)
+async function downloadOne(pin: PinData): Promise<void> {
+  return new Promise(async (resolve) => {
+    // 处理文件名非法字符（清理文件名）
+    const safeName = (pin.title || 'image').replace(/[\n\r\t]/g, ' ').replace(/[<>:"/\\|?*]/g, '').replace(/\s+/g, ' ').trim().slice(0, 100);
+    const filename = `Pins/${safeName}.jpg`;
+
+    browser.downloads.download({
+      url: pin.imgSrc,
+      filename: filename,
+      headers: [{ name: 'Referer', value: 'https://huaban.com/' }],
+      conflictAction: 'uniquify'
+    }, (id) => {
+      if (!id) {
+        console.warn(`跳过: ${pin.title} (可能 URL 无效)`);
+        return resolve(); // 即使失败也要 resolve，否则会阻塞队列
+      }
+
+      // 监听下载状态，只有当下载真正完成（或中断）时才释放资源
+      const listener = (delta: Browser.downloads.DownloadDelta) => {
+        if (delta.id !== id) return;
+
+        if (delta.state && delta.state.current === 'complete') {
+          browser.downloads.onChanged.removeListener(listener);
+          resolve();
+        }
+        // 处理中断或取消的情况，防止队列卡死
+        else if (delta.state && delta.state.current === 'interrupted') {
+          browser.downloads.onChanged.removeListener(listener);
+          console.warn(`下载中断: ${pin.title}`, JSON.stringify(delta));
+          resolve();
+        }
+      };
+      browser.downloads.onChanged.addListener(listener);
+    });
+  });
+}
+
+// 并发调度器
+export async function startBatchDownload(pins: PinData[], limit: number = 3) {
+  let success = 0;
+  let failed = 0;
+
+  const executing: Promise<void>[] = []; // 正在运行的任务池
+
+  for (const pin of pins) {
+    // 创建任务
+    const task = downloadOne(pin);
+
+    // 加入任务池
+    const wrapper = task.finally(() => {
+      const idx = executing.indexOf(wrapper);
+      if (idx !== -1) executing.splice(idx, 1);
+    });
+    executing.push(wrapper);
+
+    // 关键逻辑：如果池子满了（达到 limit），等待任意一个任务完成
+    if (executing.length >= limit) {
+      await Promise.race(executing);
+    }
+  }
+
+  // 等待剩余任务全部完成
+  await Promise.all(executing);
+  console.log("所有下载任务已处理完毕");
+
+  return { success, failed, total: pins.length };
+}

entrypoints/popup/main.ts

@@ -1,5 +1,6 @@
 import './style.css';
 import type { PinData } from '../../components/pin-collector';
+import { startBatchDownload } from '../background';
 
 document.querySelector<HTMLDivElement>('#app')!.innerHTML = `
   <div class="popup">
@@ -10,11 +11,6 @@ document.querySelector<HTMLDivElement>('#app')!.innerHTML = `
       <button id="start-btn">▶ 开始加载</button>
       <button id="stop-btn">⏹ 停止</button>
     </div>
-    <div class="download-options">
-      <label>
-        并行数: <input type="number" id="concurrency" value="5" min="1" max="20" style="width:50px" />
-      </label>
-    </div>
     <div id="status"></div>
     <div id="pinList"></div>
   </div>
@@ -24,19 +20,18 @@ document.querySelector<HTMLDivElement>('#app')!.innerHTML = `
 document.getElementById('collectBtn')!.addEventListener('click', async () => {
   showStatus('收集中...', 'info');
   try {
-    const [tab] = await browser.tabs.query({ active: true, currentWindow: true });
-    if (!tab?.id) {
-      showStatus('无法获取当前标签页', 'error');
-      return;
-    }
-    const response = await browser.tabs.sendMessage(tab.id, {
-      type: 'COLLECT_PINS',
-    });
-    if (response?.success) {
-      // await browser.storage.local.set({ collectedPins: response.pins });
-      // renderPins(response.pins as PinData[]);
     await loadAndRender();
-      showStatus(`✅ 已收集 ${response.count} 个 Pin`, 'success');
+
+    // 下载
+    const result = (await browser.storage.local.get('collectedPins')) as {
+      collectedPins?: PinData[];
+    };
+    const pins: PinData[] = result.collectedPins || [];
+    if (pins.length > 0) {
+      showStatus(`开始下载 ${pins.length} 张...`, 'info');
+      browser.runtime.sendMessage({ type: 'DOWNLOAD_PINS', pins, concurrency: 3 });
+    } else {
+      showStatus('没有可下载的图片', 'error');
     }
   } catch (e) {
     const errMsg = e instanceof Error ? e.message : String(e);
@@ -126,4 +121,11 @@ browser.runtime.onMessage.addListener(async (msg) => {
         `✅ 加载完成 · 共 ${msg.totalItems} 条`;
     }
   }
+  if (msg.type === 'DOWNLOAD_DONE') {
+    showStatus(
+      `✅ 下载完成: ${msg.success}/${msg.total}` +
+        (msg.failed > 0 ? ` (${msg.failed} 失败)` : ''),
+      'success'
+    );
+  }
 });