// ==UserScript==
// @name         豆包视频&图片下载助手
// @namespace    https://www.doubao.com/
// @version      5.1.5
// @description  自动提取豆包原始图片与无水印视频下载地址，支持视频/图片预览、一键复制、批量下载，带可拖拽悬浮按钮和红点提醒
// @author       Doubao Downloader
// @match        https://www.doubao.com/*
// @grant        GM_addStyle
// @grant        GM_getValue
// @grant        GM_setValue
// @grant        GM_notification
// @grant        GM_xmlhttpRequest
// @grant        unsafeWindow
// @connect      doubao.com
// @connect      doubaocdn.com
// @connect      byteimg.com
// @connect      snssdk.com
// @run-at       document-start
// @noframes
// @supportURL   https://github.com
// @homepageURL  https://github.com
// @license MIT
//
// 免责声明：本脚本仅供学习和参考，切勿用于违法或商用，否则后果自负。
//
// ==/UserScript==

(function () {
  'use strict';

  const videoLinks = new Map();
  const imageLinks = new Map();
  const processedVideoSrcs = new Set();
  const processedImageSrcs = new Set();
  const videoAliasToKey = new Map();
  const imageAliasToKey = new Map();
  const pageWindow = typeof unsafeWindow !== 'undefined' ? unsafeWindow : window;
  let activeTab = 'video';
  let dataHooksInstalled = false;
  let creationNodeCache = null;
  let refreshTimer = null;

  const API_QUERY = 'aid=497858&device_platform=web&samantha_web=1&use-olympus-account=1&version_code=20800&pkg_type=release_version';
  const API_HOME = `/samantha/aispace/homepage?${API_QUERY}`;
  const API_NODE = `/samantha/aispace/node_info?${API_QUERY}`;
  const API_DOWNLOAD = `/samantha/aispace/get_download_info?${API_QUERY}`;

  GM_addStyle(`
    #db-dl-btn, #db-dl-panel {
      --bg: #ffffff;
      --bg-sub: #f8fafc;
      --bg-elevated: #f1f5f9;
      --bg-hover: #f1f5f9;
      --border: #e2e8f0;
      --border-strong: #cbd5e1;
      --text: #0f172a;
      --text-sub: #475569;
      --text-muted: #94a3b8;
      --primary: #2563eb;
      --primary-hover: #1d4ed8;
      --primary-soft: #eff6ff;
      --danger: #ef4444;
      --danger-soft: #fef2f2;
      --danger-hover: #dc2626;
      --success: #10b981;
      --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.04);
      --shadow: 0 2px 8px rgba(15, 23, 42, 0.06);
      --shadow-lg: -8px 0 32px rgba(15, 23, 42, 0.12);
    }

    #db-dl-panel, #db-dl-btn, #db-dl-toast {
      font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

    #db-dl-btn {
      position: fixed;
      bottom: 24px;
      right: 24px;
      z-index: 2147483646;
      width: 48px;
      height: 48px;
      border-radius: 12px;
      background: #ffffff;
      box-shadow: 0 4px 14px rgba(15, 23, 42, 0.18);
      cursor: move;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: transform 0.2s ease, box-shadow 0.2s ease;
      border: 1px solid var(--border);
      outline: none;
      user-select: none;
      -webkit-tap-highlight-color: transparent;
    }
    #db-dl-btn:hover { transform: translateY(-2px); box-shadow: 0 6px 20px rgba(15, 23, 42, 0.25); }
    #db-dl-btn:active { transform: translateY(0); cursor: grabbing; }
    #db-dl-btn img { width: 32px; height: 32px; pointer-events: none; border-radius: 6px; }
    #db-dl-btn .badge {
      position: absolute;
      top: -4px;
      right: -4px;
      width: 14px;
      height: 14px;
      border-radius: 50%;
      background: #ef4444;
      box-shadow: 0 0 0 2px #ffffff, 0 2px 8px rgba(239, 68, 68, 0.5);
      pointer-events: none;
      transition: transform 0.2s ease;
      z-index: 10;
    }
    #db-dl-btn .badge.hidden { display: none; }
    #db-dl-btn .badge.pulse { animation: db-badge-pulse 1.6s ease-in-out infinite; }
    @keyframes db-badge-pulse {
      0%,100% { box-shadow: 0 0 0 2px #ffffff, 0 2px 6px rgba(239, 68, 68, 0.4); transform: scale(1); }
      50% { box-shadow: 0 0 0 2px #ffffff, 0 0 0 8px rgba(239, 68, 68, 0.15), 0 2px 8px rgba(239, 68, 68, 0.5); transform: scale(1.05); }
    }

    #db-dl-overlay {
      position: fixed;
      inset: 0;
      z-index: 2147483647;
      background: rgba(15, 23, 42, 0.4);
      opacity: 0;
      pointer-events: none;
      transition: opacity 0.25s ease;
    }
    #db-dl-overlay.show { opacity: 1; pointer-events: auto; }

    #db-dl-panel {
      position: fixed;
      top: 0;
      right: 0;
      bottom: 0;
      width: 480px;
      max-width: 92vw;
      z-index: 2147483648;
      background: var(--bg);
      color: var(--text);
      box-shadow: var(--shadow-lg);
      transform: translateX(105%);
      transition: transform 0.3s cubic-bezier(0.22, 0.61, 0.36, 1);
      display: flex;
      flex-direction: column;
      font-size: 14px;
    }
    #db-dl-panel.open { transform: translateX(0); }

    .db-panel-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 18px 16px 0 20px;
      flex-shrink: 0;
      background: var(--bg);
    }
    .db-panel-header .title {
      font-size: 16px;
      font-weight: 600;
      color: var(--text);
      display: flex;
      align-items: center;
      gap: 8px;
      letter-spacing: -0.01em;
      flex: 1;
      min-width: 0;
    }
    .db-panel-header .title svg { width: 22px; height: 22px; flex-shrink: 0; border-radius: 5px; }
    .db-panel-header .title-text { flex-shrink: 0; }
    .db-panel-header .count-tag {
      background: var(--primary);
      color: #ffffff;
      font-size: 11px;
      font-weight: 700;
      padding: 3px 9px;
      border-radius: 10px;
      min-width: 24px;
      text-align: center;
      flex-shrink: 0;
    }
    .db-panel-header .close-btn {
      width: 30px;
      height: 30px;
      border-radius: 8px;
      border: 1px solid var(--border);
      background: var(--bg);
      color: var(--text-sub);
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: all 0.15s ease;
      line-height: 1;
      font-size: 18px;
      flex-shrink: 0;
    }
    .db-panel-header .close-btn:hover { background: var(--danger-soft); color: var(--danger); border-color: var(--danger); }

    .db-panel-tabs {
      display: flex;
      gap: 4px;
      padding: 12px 20px 0;
      flex-shrink: 0;
      background: var(--bg);
    }
    .db-panel-tabs button {
      flex: 1;
      padding: 8px 12px;
      border: none;
      background: transparent;
      color: var(--text-sub);
      font-size: 13px;
      font-weight: 500;
      cursor: pointer;
      transition: all 0.15s ease;
      border-radius: 8px 8px 0 0;
      font-family: inherit;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
      border-bottom: 2px solid transparent;
    }
    .db-panel-tabs button svg { width: 14px; height: 14px; fill: currentColor; }
    .db-panel-tabs button:hover { color: var(--text); background: var(--bg-hover); }
    .db-panel-tabs button.active {
      color: var(--primary);
      border-bottom-color: var(--primary);
    }
    .db-panel-tabs .tab-count {
      background: var(--bg-elevated);
      color: var(--text-sub);
      font-size: 10px;
      font-weight: 700;
      padding: 1px 6px;
      border-radius: 8px;
      min-width: 18px;
      text-align: center;
    }
    .db-panel-tabs button.active .tab-count {
      background: var(--primary-soft);
      color: var(--primary);
    }

    .db-panel-toolbar {
      display: flex;
      gap: 6px;
      padding: 10px 16px;
      flex-shrink: 0;
      background: var(--bg);
      border-bottom: 1px solid var(--border);
    }
    .db-panel-toolbar button {
      flex: 1;
      padding: 7px 0;
      border-radius: 6px;
      border: 1px solid var(--border);
      background: var(--bg);
      color: var(--text-sub);
      font-size: 12px;
      cursor: pointer;
      transition: all 0.15s ease;
      font-weight: 500;
      font-family: inherit;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 4px;
    }
    .db-panel-toolbar button svg { width: 12px; height: 12px; fill: currentColor; }
    .db-panel-toolbar button:hover { background: var(--primary-soft); color: var(--primary); border-color: var(--primary); }
    .db-panel-toolbar button.primary {
      background: var(--primary);
      color: #fff;
      border-color: var(--primary);
      box-shadow: 0 1px 2px rgba(37, 99, 235, 0.25);
    }
    .db-panel-toolbar button.primary:hover { background: var(--primary-hover); border-color: var(--primary-hover); color: #fff; }

    .db-panel-list {
      flex: 1;
      overflow-y: auto;
      padding: 12px;
      overscroll-behavior: contain;
      background: var(--bg-sub);
    }
    .db-panel-list::-webkit-scrollbar { width: 6px; }
    .db-panel-list::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 3px; }
    .db-panel-list::-webkit-scrollbar-track { background: transparent; }

    .db-disclaimer {
      flex-shrink: 0;
      padding: 10px 16px;
      border-top: 1px solid var(--border);
      font-size: 11px;
      color: var(--text-muted);
      text-align: center;
      line-height: 1.5;
      background: var(--bg);
    }

    .db-empty-state {
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      height: 100%;
      color: var(--text-muted);
      text-align: center;
      padding: 40px 20px;
      gap: 6px;
    }
    .db-empty-state .icon-wrap {
      width: 64px;
      height: 64px;
      border-radius: 16px;
      background: var(--bg);
      border: 1px solid var(--border);
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 14px;
    }
    .db-empty-state .icon-wrap svg { width: 28px; height: 28px; fill: var(--primary); opacity: 0.5; }
    .db-empty-state .hint { font-size: 12px; color: var(--text-muted); margin-top: 2px; }

    .db-video-card, .db-image-card {
      background: var(--bg);
      border: 1px solid var(--border);
      border-radius: 10px;
      padding: 12px;
      margin-bottom: 10px;
      transition: border-color 0.15s ease, box-shadow 0.15s ease;
      animation: db-card-in 0.3s ease;
      position: relative;
    }
    @keyframes db-card-in {
      from { opacity: 0; transform: translateY(4px); }
      to { opacity: 1; transform: translateY(0); }
    }
    @keyframes db-card-out {
      to { opacity: 0; transform: translateX(40px); height: 0; padding: 0; margin: 0; border-width: 0; }
    }
    .db-video-card:hover, .db-image-card:hover { border-color: var(--primary); box-shadow: 0 2px 12px rgba(37, 99, 235, 0.08); }

    .db-card-row {
      display: flex;
      align-items: center;
      gap: 10px;
      margin-bottom: 12px;
    }
    .db-thumb {
      width: 80px;
      height: 60px;
      border-radius: 6px;
      background: var(--bg-elevated);
      flex-shrink: 0;
      display: flex;
      align-items: center;
      justify-content: center;
      overflow: hidden;
      border: 1px solid var(--border);
    }
    .db-thumb.video { height: 45px; }
    .db-thumb img { width: 100%; height: 100%; object-fit: cover; pointer-events: none; }
    .db-thumb svg { width: 22px; height: 22px; fill: var(--primary); opacity: 0.5; }

    .db-card-info { flex: 1; min-width: 0; }
    .db-card-info .meta {
      display: flex;
      align-items: center;
      gap: 6px;
      font-size: 11px;
      color: var(--text-muted);
      margin-bottom: 4px;
    }
    .db-card-info .meta .dot { width: 3px; height: 3px; border-radius: 50%; background: var(--border-strong); }
    .db-card-info .meta .badge-mini {
      background: var(--primary-soft);
      color: var(--primary);
      font-size: 10px;
      font-weight: 600;
      padding: 1px 6px;
      border-radius: 4px;
    }
    .db-card-info .filename {
      font-size: 12px;
      color: var(--text);
      font-weight: 500;
      overflow: hidden;
      text-overflow: ellipsis;
      white-space: nowrap;
      font-family: 'SF Mono', 'Cascadia Code', Consolas, monospace;
      line-height: 1.4;
    }

    .db-delete-btn {
      position: absolute;
      top: 8px;
      right: 8px;
      width: 22px;
      height: 22px;
      border-radius: 5px;
      border: none;
      background: transparent;
      color: var(--text-muted);
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      opacity: 0;
      transition: all 0.15s ease;
    }
    .db-video-card:hover .db-delete-btn, .db-image-card:hover .db-delete-btn { opacity: 1; }
    .db-delete-btn:hover { background: var(--danger-soft); color: var(--danger); }
    .db-delete-btn svg { width: 12px; height: 12px; fill: currentColor; }

    .db-card-actions { display: flex; gap: 6px; }
    .db-card-actions button {
      flex: 1;
      padding: 7px 0;
      border-radius: 6px;
      border: 1px solid var(--border);
      background: var(--bg);
      color: var(--text-sub);
      font-size: 12px;
      font-weight: 500;
      cursor: pointer;
      transition: all 0.15s ease;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 4px;
      font-family: inherit;
    }
    .db-card-actions button svg { width: 13px; height: 13px; fill: currentColor; }
    .db-card-actions button.copy-btn:hover { background: var(--primary-soft); color: var(--primary); border-color: var(--primary); }
    .db-card-actions button.dl-btn {
      background: var(--primary);
      color: #fff;
      border-color: var(--primary);
    }
    .db-card-actions button.dl-btn:hover { background: var(--primary-hover); border-color: var(--primary-hover); }
    .db-card-actions button.copied {
      background: var(--success) !important;
      border-color: var(--success) !important;
      color: #fff !important;
    }

    #db-dl-toast {
      position: fixed;
      bottom: 88px;
      left: 50%;
      transform: translateX(-50%) translateY(8px);
      z-index: 2147483649;
      background: var(--text);
      color: var(--bg);
      padding: 9px 18px;
      border-radius: 8px;
      font-size: 12px;
      font-weight: 500;
      opacity: 0;
      pointer-events: none;
      transition: all 0.2s ease;
      white-space: nowrap;
      box-shadow: 0 4px 16px rgba(15, 23, 42, 0.2);
    }
    #db-dl-toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

    #db-preview-modal {
      position: fixed;
      inset: 0;
      z-index: 2147483650;
      background: rgba(0, 0, 0, 0.85);
      display: none;
      align-items: center;
      justify-content: center;
      padding: 32px;
      backdrop-filter: blur(8px);
    }
    #db-preview-modal.show { display: flex; animation: db-modal-in 0.25s ease; }
    @keyframes db-modal-in {
      from { opacity: 0; }
      to { opacity: 1; }
    }
    #db-preview-modal .preview-content {
      position: relative;
      max-width: 92vw;
      max-height: 92vh;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    #db-preview-modal img,
    #db-preview-modal video {
      max-width: 92vw;
      max-height: 88vh;
      border-radius: 8px;
      box-shadow: 0 8px 40px rgba(0, 0, 0, 0.5);
      background: #000;
      display: block;
    }
    #db-preview-modal .preview-close {
      position: fixed;
      top: 20px;
      right: 24px;
      width: 40px;
      height: 40px;
      border-radius: 50%;
      border: none;
      background: rgba(255, 255, 255, 0.15);
      color: #fff;
      font-size: 22px;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: background 0.15s;
      z-index: 10;
      line-height: 1;
    }
    #db-preview-modal .preview-close:hover { background: rgba(255, 255, 255, 0.3); }
    #db-preview-modal .preview-info {
      position: fixed;
      bottom: 24px;
      left: 50%;
      transform: translateX(-50%);
      background: rgba(0, 0, 0, 0.7);
      color: #fff;
      padding: 10px 18px;
      border-radius: 8px;
      font-size: 12px;
      max-width: 80vw;
      overflow: hidden;
      text-overflow: ellipsis;
      white-space: nowrap;
      font-family: 'SF Mono', 'Cascadia Code', Consolas, monospace;
    }
    #db-preview-modal video {
      outline: none;
    }

    .db-thumb { cursor: pointer; position: relative; }
    .db-thumb::after {
      content: '预览';
      position: absolute;
      inset: 0;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 12px;
      font-weight: 600;
      color: rgba(255, 255, 255, 0);
      letter-spacing: 0.5px;
      transition: all 0.15s ease;
      pointer-events: none;
      border-radius: 6px;
    }
    .db-video-card:hover .db-thumb::after,
    .db-image-card:hover .db-thumb::after {
      background: rgba(15, 23, 42, 0.55);
      color: #fff;
    }
  `);

  function showToast(msg, duration) {
    let toast = document.getElementById('db-dl-toast');
    if (!toast) {
      toast = document.createElement('div');
      toast.id = 'db-dl-toast';
      document.body.appendChild(toast);
    }
    toast.textContent = msg;
    toast.classList.add('show');
    clearTimeout(toast._timer);
    toast._timer = setTimeout(() => toast.classList.remove('show'), duration || 1800);
  }

  function normalizeKey(url) {
    try {
      const u = new URL(url, location.href);
      if (/flow-imagex|byteimg/i.test(u.hostname)) {
        return 'image:' + u.pathname.split('~tplv-')[0];
      }
      return u.origin + u.pathname;
    } catch (e) {
      return url.split('?')[0].split('#')[0];
    }
  }

  function decodeHtmlUrl(url) {
    return String(url || '')
      .replace(/&/g, '&')
      .replace(/\\u002F/gi, '/')
      .replace(/\\\//g, '/');
  }

  function hasWatermark(url) {
    const value = decodeHtmlUrl(url).toLowerCase();
    return /(^|[\/_:=&-])(?:watermark|video_gen_watermark[^\/?]*)|(?:^|[\/_:=&-])lwm\d+/.test(value);
  }

  function isStaticUiImage(url) {
    const value = String(url || '').toLowerCase();
    return value.includes('user-avatar') ||
      value.includes('/rc/icon/') ||
      value.includes('/favicon/') ||
      value.includes('doubao_avatar') ||
      value.includes('/logo');
  }

  function isVideoUrl(url) {
    if (!url) return false;
    if (url.includes('.mp4') || url.includes('.m3u8') || url.includes('.flv') || url.includes('.webm')) return true;
    if (url.includes('mime_type=video')) return true;
    if (url.includes('/video/') && url.includes('douyin')) return true;
    return false;
  }

  function isImageUrl(url) {
    if (!url) return false;
    if (/\.(png|jpg|jpeg|webp|gif|bmp|svg)(\?|$|#)/i.test(url)) return true;
    if (url.includes('mime_type=image')) return true;
    if (url.includes('imagex') || url.includes('rc_gen_image')) return true;
    if (url.includes('p1-sign') || url.includes('p3-flow-imagex') || url.includes('byteimg.com')) return true;
    return false;
  }

  function extractVideoSrc(element) {
    if (!element) return null;
    if (element.tagName === 'VIDEO') {
      if (element.src && element.src.startsWith('http')) return element.src;
      if (element.currentSrc && element.currentSrc.startsWith('http')) return element.currentSrc;
      const source = element.querySelector('source[src]');
      if (source && source.src.startsWith('http')) return source.src;
    }
    if (element.querySelectorAll) {
      const innerVid = element.querySelector('video[src]');
      if (innerVid && innerVid.src && innerVid.src.startsWith('http')) return innerVid.src;
    }
    const dataUrl = element.getAttribute && element.getAttribute('data-url');
    if (dataUrl && dataUrl.startsWith('http')) return dataUrl;
    return null;
  }

  function extractImageSrc(element) {
    if (!element) return null;
    if (element.tagName === 'IMG') {
      const src = element.src || element.currentSrc;
      if (src && src.startsWith('http')) return src;
      const dataSrc = element.getAttribute('data-src') || element.getAttribute('data-original');
      if (dataSrc && dataSrc.startsWith('http')) return dataSrc;
    }
    if (element.tagName === 'SOURCE') {
      if (element.src && element.src.startsWith('http')) return element.src;
      const srcset = element.srcset;
      if (srcset) {
        const firstUrl = srcset.split(',')[0].trim().split(' ')[0];
        if (firstUrl.startsWith('http')) return firstUrl;
      }
    }
    if (element.querySelectorAll) {
      const innerImg = element.querySelector('img[src]');
      if (innerImg) {
        const src = innerImg.src || innerImg.currentSrc;
        if (src && src.startsWith('http')) return src;
      }
    }
    const bgImg = element.style && element.style.backgroundImage;
    if (bgImg && bgImg.includes('url(')) {
      const match = bgImg.match(/url\(["']?(https?:\/\/[^"')]+)["']?\)/);
      if (match) return match[1];
    }
    return null;
  }

  function getObjectUrl(value) {
    if (!value) return '';
    if (typeof value === 'string') return decodeHtmlUrl(value);
    if (typeof value === 'object' && typeof value.url === 'string') return decodeHtmlUrl(value.url);
    return '';
  }

  function collectUrls(value, result, depth) {
    if (value == null || depth > 5) return result;
    if (typeof value === 'string') {
      const url = decodeHtmlUrl(value);
      if (/^https?:\/\//i.test(url)) result.add(url);
      return result;
    }
    if (typeof value !== 'object') return result;
    if (Array.isArray(value)) {
      value.forEach(item => collectUrls(item, result, depth + 1));
      return result;
    }
    for (const [key, item] of Object.entries(value)) {
      if (typeof item === 'string' && /^https?:\/\//i.test(decodeHtmlUrl(item))) {
        result.add(decodeHtmlUrl(item));
      } else if (item && typeof item === 'object' && (key === 'url' || key === 'url_formats' || key === 'format_urls' || depth < 2)) {
        collectUrls(item, result, depth + 1);
      }
    }
    return result;
  }

  function chooseImageDownloadUrl(image) {
    const rawCandidates = [
      getObjectUrl(image && image.image_ori_raw),
      getObjectUrl(image && image.raw_image),
      getObjectUrl(image && image.image_original),
      getObjectUrl(image && image.original_image),
      getObjectUrl(image && image.image_ori),
      getObjectUrl(image && image.image_preview),
      getObjectUrl(image && image.image_thumb),
      getObjectUrl(image && image.url)
    ].filter(Boolean);
    const raw = rawCandidates.find(url => isImageUrl(url) && !hasWatermark(url));
    return raw || '';
  }

  function chooseImagePreviewUrl(image) {
    return [
      getObjectUrl(image && image.image_thumb),
      getObjectUrl(image && image.image_preview),
      getObjectUrl(image && image.image_ori),
      getObjectUrl(image && image.image_ori_raw),
      getObjectUrl(image && image.raw_image),
      chooseImageDownloadUrl(image)
    ].find(url => url && isImageUrl(url)) || '';
  }

  function findImageEntryForAliases(aliasKeys) {
    for (const alias of aliasKeys) {
      const key = imageAliasToKey.get(alias);
      if (key && imageLinks.has(key)) return key;
    }
    for (const [key, item] of imageLinks) {
      const candidates = [item.downloadSrc, item.previewSrc, item.src];
      if (candidates.some(url => url && aliasKeys.includes(normalizeKey(url)))) return key;
    }
    return null;
  }

  function registerImageData(image) {
    if (!image || typeof image !== 'object') return;
    const downloadSrc = chooseImageDownloadUrl(image);
    if (!downloadSrc) return;
    const previewSrc = chooseImagePreviewUrl(image) || downloadSrc;
    const allUrls = collectUrls(image, new Set(), 0);
    allUrls.add(downloadSrc);
    if (previewSrc) allUrls.add(previewSrc);
    const aliasKeys = [...allUrls].map(normalizeKey);
    const key = normalizeKey(downloadSrc);
    const existingKey = (imageLinks.has(key) && key) || findImageEntryForAliases(aliasKeys);
    const timestamp = new Date().toLocaleTimeString('zh-CN', { hour12: false });
    const item = existingKey ? imageLinks.get(existingKey) : {
      src: downloadSrc,
      previewSrc,
      downloadSrc,
      type: 'image',
      title: extractFilename(downloadSrc, '.png'),
      timestamp
    };

    const finalKey = existingKey || key;
    item.src = downloadSrc;
    item.downloadSrc = downloadSrc;
    item.previewSrc = previewSrc;
    item.sizeKb = item.sizeKb || Math.round((Number(image.image_ori_raw?.size) || Number(image.image_ori?.size) || 0) / 1024) || 0;
    imageLinks.set(finalKey, item);
    processedImageSrcs.add(finalKey);
    aliasKeys.forEach(alias => {
      imageAliasToKey.set(alias, finalKey);
      processedImageSrcs.add(alias);
    });

    for (const [otherKey, otherItem] of imageLinks) {
      if (otherKey === finalKey) continue;
      const otherAliases = [otherItem.downloadSrc, otherItem.previewSrc, otherItem.src]
        .filter(Boolean)
        .map(normalizeKey);
      if (otherAliases.some(alias => aliasKeys.includes(alias))) {
        imageLinks.delete(otherKey);
        processedImageSrcs.delete(otherKey);
      }
    }
    scheduleMediaRefresh();
  }

  function isMediaImageObject(image) {
    if (!image || typeof image !== 'object') return false;
    if (image.image_ori_raw || image.image_ori || image.raw_image || image.image_720) return true;
    return typeof image.key === 'string' && /(image|rc_gen_image)/i.test(image.key);
  }

  function registerVideoData(video) {
    if (!video || typeof video !== 'object' || !video.vid) return;
    const vid = String(video.vid);
    const allUrls = collectUrls(video, new Set(), 0);
    const messageUrls = [...allUrls].filter(isVideoUrl);
    const previewSrc = messageUrls.find(url => url) || '';
    const cleanSrc = messageUrls.find(url => !hasWatermark(url)) || '';
    const aliasKeys = [
      `vid:${vid}`,
      ...allUrls.map(normalizeKey)
    ];
    const key = `video:${vid}`;
    const existingKey = videoAliasToKey.get(`vid:${vid}`) ||
      aliasKeys.map(alias => videoAliasToKey.get(alias)).find(Boolean) ||
      (videoLinks.has(key) ? key : null);
    const item = existingKey ? videoLinks.get(existingKey) : {
      src: previewSrc,
      previewSrc,
      downloadSrc: cleanSrc,
      type: 'video',
      title: extractFilename(cleanSrc || previewSrc, '.mp4'),
      timestamp: new Date().toLocaleTimeString('zh-CN', { hour12: false })
    };

    const finalKey = existingKey || key;
    item.vid = vid;
    item.previewSrc = item.previewSrc || previewSrc;
    item.src = item.previewSrc || previewSrc;
    if (cleanSrc && !hasWatermark(cleanSrc)) item.downloadSrc = cleanSrc;
    if (!item.resolution && video.width && video.height) item.resolution = `${video.width}×${video.height}`;
    if (!item.duration && video.duration) item.duration = Number(video.duration);
    videoLinks.set(finalKey, item);
    processedVideoSrcs.add(finalKey);
    aliasKeys.forEach(alias => {
      videoAliasToKey.set(alias, finalKey);
      processedVideoSrcs.add(alias);
    });

    for (const [otherKey, otherItem] of videoLinks) {
      if (otherKey === finalKey || otherItem.vid) continue;
      const otherAliases = [otherItem.previewSrc, otherItem.src]
        .filter(Boolean)
        .map(normalizeKey);
      if (otherAliases.some(alias => aliasKeys.includes(alias))) {
        videoLinks.delete(otherKey);
        processedVideoSrcs.delete(otherKey);
      }
    }
    scheduleMediaRefresh();
  }

  function captureMediaData(root) {
    if (!root || typeof root !== 'object') return;
    const visited = new WeakSet();
    let inspected = 0;

    function walk(value, depth, mediaContext) {
      if (!value || typeof value !== 'object' || depth > 24 || inspected > 12000 || visited.has(value)) return;
      visited.add(value);
      inspected++;

      const looksLikeCreation = Boolean(value.gen_detail || value.creation_meta || value.can_publish !== undefined);
      if ((mediaContext || looksLikeCreation) && value.video && typeof value.video === 'object' && value.video.vid) {
        registerVideoData(value.video);
      }
      if ((mediaContext || looksLikeCreation) && value.image && isMediaImageObject(value.image)) {
        registerImageData(value.image);
      }

      if (Array.isArray(value)) {
        for (const child of value) walk(child, depth + 1, mediaContext);
      } else {
        for (const [key, child] of Object.entries(value)) {
          const childContext = mediaContext || key === 'creations' || key === 'attachments' || key === 'creation_list';
          walk(child, depth + 1, childContext);
        }
      }
    }

    try {
      walk(root, 0, false);
    } catch (e) {
      console.debug('[豆包下载助手] 媒体数据解析失败', e);
    }
  }

  function installDataHooks() {
    if (dataHooksInstalled) return;
    dataHooksInstalled = true;

    try {
      const pageJSON = pageWindow.JSON;
      if (pageJSON && typeof pageJSON.parse === 'function' && !pageJSON.parse.__dbWrapped) {
        const nativeParse = pageJSON.parse;
        const wrappedParse = function () {
          const value = Reflect.apply(nativeParse, pageJSON, arguments);
          captureMediaData(value);
          return value;
        };
        wrappedParse.__dbWrapped = true;
        pageJSON.parse = wrappedParse;
      }
    } catch (e) {
      console.debug('[豆包下载助手] 无法挂接 JSON 解析器', e);
    }

    try {
      const nativeFetch = pageWindow.fetch;
      if (typeof nativeFetch === 'function' && !nativeFetch.__dbWrapped) {
        const wrappedFetch = function () {
          return Reflect.apply(nativeFetch, this, arguments).then(response => {
            if (response && typeof response.json === 'function') {
              const nativeJson = response.json;
              response.json = function () {
                return Reflect.apply(nativeJson, response, arguments).then(data => {
                  captureMediaData(data);
                  return data;
                });
              };
            }
            return response;
          });
        };
        wrappedFetch.__dbWrapped = true;
        pageWindow.fetch = wrappedFetch;
      }
    } catch (e) {
      console.debug('[豆包下载助手] 无法挂接网络响应', e);
    }
  }

  function scanEmbeddedData() {
    const globals = [
      '_ROUTER_DATA',
      '__NEXT_DATA__',
      '__INITIAL_STATE__',
      '__FLOW_STATE__',
      '__DOUBAO_STATE__'
    ];
    for (const name of globals) {
      try {
        if (pageWindow[name]) captureMediaData(pageWindow[name]);
      } catch (e) {}
    }
    document.querySelectorAll('script[type="application/json"]').forEach(script => {
      try {
        captureMediaData(pageWindow.JSON.parse(script.textContent || 'null'));
      } catch (e) {}
    });
  }

  function getActiveMap() { return activeTab === 'video' ? videoLinks : imageLinks; }
  function getActiveProcessed() { return activeTab === 'video' ? processedVideoSrcs : processedImageSrcs; }
  function getActiveExtractor() { return activeTab === 'video' ? extractVideoSrc : extractImageSrc; }

  function processVideo(el) {
    const src = extractVideoSrc(el);
    if (!src) return;
    const cleanSrc = decodeHtmlUrl(src);
    const key = normalizeKey(cleanSrc);
    const capturedKey = videoAliasToKey.get(key);
    if (capturedKey && videoLinks.has(capturedKey)) {
      const item = videoLinks.get(capturedKey);
      if (!item.previewSrc) item.previewSrc = cleanSrc;
      return;
    }
    if (processedVideoSrcs.has(key)) return;

    const timestamp = new Date().toLocaleTimeString('zh-CN', { hour12: false });
    const filename = extractFilename(cleanSrc, '.mp4');
    videoLinks.set(key, {
      src: cleanSrc,
      previewSrc: cleanSrc,
      downloadSrc: hasWatermark(cleanSrc) ? '' : cleanSrc,
      type: 'video',
      title: filename,
      timestamp,
      resolution: extractResolution(cleanSrc)
    });
    processedVideoSrcs.add(key);
    scheduleMediaRefresh();
  }

  function processImage(src, sizeKb) {
    if (!src || !src.startsWith('http')) return;
    if (!isImageUrl(src)) return;
    if (isStaticUiImage(src)) return;
    const cleanSrc = decodeHtmlUrl(src);
    const key = normalizeKey(cleanSrc);
    const capturedKey = imageAliasToKey.get(key);
    if (capturedKey && imageLinks.has(capturedKey)) return;
    if (processedImageSrcs.has(key)) return;

    const timestamp = new Date().toLocaleTimeString('zh-CN', { hour12: false });
    const filename = extractFilename(cleanSrc, '.png');

    imageLinks.set(key, {
      src: cleanSrc,
      previewSrc: cleanSrc,
      downloadSrc: hasWatermark(cleanSrc) ? '' : cleanSrc,
      type: 'image',
      title: filename,
      timestamp,
      sizeKb
    });
    processedImageSrcs.add(key);
    scheduleMediaRefresh();
  }

  function processImageElement(el) {
    if (!el || el.closest?.('#db-dl-panel, #db-preview-modal, .flow_chat_sidebar, [class*="sidebar"], nav')) return;
    if (el.closest?.('[data-remote-icon], header')) return;
    const rect = el.getBoundingClientRect?.();
    if (rect && rect.width < 72) return;
    const url = extractImageSrc(el);
    if (url && isImageUrl(url) && !isStaticUiImage(url)) processImage(url);
  }

  function processElement(el) {
    const element = el && el.nodeType === Node.TEXT_NODE ? el.parentElement : el;
    if (!element) return;
    const url = extractImageSrc(element);
    if (url && isImageUrl(url) && !isStaticUiImage(url)) {
      processImageElement(element);
      return;
    }
    const vidUrl = extractVideoSrc(element);
    if (vidUrl) processVideo(element);
  }

  function extractFilename(url, defaultExt) {
    try {
      const u = new URL(url);
      const pathParts = u.pathname.split('/').filter(Boolean);
      if (pathParts.length > 0) {
        const last = decodeURIComponent(pathParts[pathParts.length - 1]).split('~tplv-')[0];
        if (/\.(png|jpe?g|webp|gif|bmp|svg|mp4|webm|mov|flv)$/i.test(last)) return last;
        return last + defaultExt;
      }
    } catch (e) {}
    return 'file_' + Date.now() + defaultExt;
  }

  function extractResolution(url) {
    const match = url.match(/br=(\d+)/);
    if (match) {
      const br = parseInt(match[1]);
      return br > 1000 ? (br / 1000).toFixed(1) + ' Mbps' : br + ' kbps';
    }
    return '';
  }

  function formatSize(kb) {
    if (!kb) return '';
    if (kb > 1024) return (kb / 1024).toFixed(1) + ' MB';
    return kb + ' KB';
  }

  function scheduleMediaRefresh() {
    clearTimeout(refreshTimer);
    refreshTimer = setTimeout(() => {
      updateCounts();
      updateBadge();
      const panel = document.getElementById('db-dl-panel');
      if (panel && panel.classList.contains('open')) renderActiveTab();
    }, 120);
  }

  async function apiPost(url, body) {
    const response = await pageWindow.fetch(url, {
      method: 'POST',
      credentials: 'include',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify(body || {})
    });
    if (!response.ok) throw new Error(`请求失败：${response.status} ${response.statusText}`);
    const data = await response.json();
    if (data && data.code !== undefined && data.code !== 0) {
      throw new Error(data.message || '豆包接口请求失败');
    }
    return data;
  }

  async function getCreationNodes(forceRefresh) {
    if (creationNodeCache && !forceRefresh) return creationNodeCache;
    creationNodeCache = (async () => {
      const home = await apiPost(API_HOME, {});
      const creationId = home.data?.children?.find(item => item.name === '我的创作')?.id;
      if (!creationId) throw new Error('未找到“我的创作”节点');

      const result = await apiPost(API_NODE, {
        node_id: creationId,
        need_full_path: true,
        size: 500,
        sort_param: {
          need_sort_config: true,
          sort_order: 1,
          sort_type: 0
        }
      });
      const index = new Map();
      for (const node of result.data?.children || []) {
        if (node && node.key && node.id) index.set(String(node.key), String(node.id));
      }
      return index;
    })().catch(error => {
      creationNodeCache = null;
      throw error;
    });
    return creationNodeCache;
  }

  async function resolveVideoDownload(item) {
    if (item.downloadSrc && isVideoUrl(item.downloadSrc) && !hasWatermark(item.downloadSrc)) {
      return item.downloadSrc;
    }
    if (!item.vid) {
      throw new Error('未捕获视频标识，请刷新页面并播放一次视频');
    }

    let nodeIndex = await getCreationNodes(false);
    let nodeId = nodeIndex.get(String(item.vid));
    if (!nodeId) {
      nodeIndex = await getCreationNodes(true);
      nodeId = nodeIndex.get(String(item.vid));
    }
    if (!nodeId) throw new Error('豆包创作列表中暂未找到该视频');

    const data = await apiPost(API_DOWNLOAD, { requests: [{ node_id: nodeId }] });
    const info = data.data?.download_infos?.[0];
    const cleanUrl = [info?.main_url, info?.backup_url]
      .find(url => url && isVideoUrl(url) && !hasWatermark(url));
    if (!cleanUrl) throw new Error('豆包未返回可用的无水印视频地址');

    item.downloadSrc = cleanUrl;
    scheduleMediaRefresh();
    return cleanUrl;
  }

  async function resolveDownloadUrl(item) {
    if (!item) throw new Error('资源不存在');
    if (item.type === 'video') return resolveVideoDownload(item);

    if (item.downloadSrc && !hasWatermark(item.downloadSrc)) return item.downloadSrc;
    scanEmbeddedData();
    if (item.downloadSrc && !hasWatermark(item.downloadSrc)) return item.downloadSrc;
    throw new Error('未捕获该图片的原始地址，请刷新页面后重试');
  }

  function scanPage() {
    document.querySelectorAll('div[class*="video-canvas-panel-player"]').forEach(processVideo);
    document.querySelectorAll('.xgplayer').forEach(processVideo);
    document.querySelectorAll('video').forEach(processVideo);

    document.querySelectorAll('img[src]').forEach(el => {
      processImageElement(el);
    });
    document.querySelectorAll('img[data-src]').forEach(el => {
      processImageElement(el);
    });
    document.querySelectorAll('source[srcset]').forEach(el => {
      const srcset = el.srcset;
      if (srcset) {
        const firstUrl = srcset.split(',')[0].trim().split(' ')[0];
        if (firstUrl.startsWith('http') && !isStaticUiImage(firstUrl)) processImage(firstUrl);
      }
    });
  }

  function setupPerformanceObserver() {
    if (!window.PerformanceObserver) return;
    try {
      const obs = new PerformanceObserver((list) => {
        for (const entry of list.getEntries()) {
          const url = entry.name;
          if (!url || !url.startsWith('http')) continue;
          if (!isImageUrl(url)) continue;
          if (!url.includes('/rc_gen_image/')) continue;
          const size = entry.transferSize ? Math.round(entry.transferSize / 1024) : 0;
          processImage(url, size);
        }
      });
      obs.observe({ type: 'resource', buffered: true });
    } catch (e) {}
  }

  function setupObserver() {
    const observer = new MutationObserver((mutations) => {
      let shouldScan = false;
      for (const mutation of mutations) {
        if (mutation.type === 'childList' && mutation.addedNodes.length > 0) {
          for (const node of mutation.addedNodes) {
            if (node.nodeType === Node.ELEMENT_NODE) {
              if (node.querySelectorAll) {
                const matches = node.querySelectorAll('video[src], img[src], img[data-src], .xgplayer, div[class*="video-canvas-panel-player"]');
                if (matches.length > 0) { shouldScan = true; break; }
              }
              if (node.tagName === 'VIDEO' || node.tagName === 'IMG' || node.tagName === 'SOURCE') {
                shouldScan = true; break;
              }
            }
          }
        }
        if (mutation.type === 'attributes') {
          if (mutation.target.tagName === 'VIDEO' && mutation.attributeName === 'src') {
            if (mutation.target.src && mutation.target.src.startsWith('http')) processVideo(mutation.target);
          }
          if (mutation.target.tagName === 'IMG' && (mutation.attributeName === 'src' || mutation.attributeName === 'data-src')) {
            processImageElement(mutation.target);
          }
        }
      }
      if (shouldScan) {
        clearTimeout(observer._debounce);
        observer._debounce = setTimeout(scanPage, 500);
      }
    });
    observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['src', 'data-src'] });
    return observer;
  }

  function buildUI() {
    const btn = document.createElement('button');
    btn.id = 'db-dl-btn';
    btn.title = '豆包视频&图片下载助手';
    btn.innerHTML = `
      <img src="https://lf-flow-web-cdn.doubao.com/obj/flow-doubao/doubao/web/doubao_avatar_new.png" width="32" height="32"
           style="border-radius:6px;display:block"
           onerror="this.replaceWith(document.createElement('span'))" />
      <span class="badge hidden"></span>
    `;
    btn.addEventListener('click', togglePanel);
    setupDrag(btn);
    restorePosition(btn);
    document.body.appendChild(btn);

    const overlay = document.createElement('div');
    overlay.id = 'db-dl-overlay';
    overlay.addEventListener('click', closePanel);
    document.body.appendChild(overlay);

    const panel = document.createElement('div');
    panel.id = 'db-dl-panel';
    panel.innerHTML = `
      <div class="db-panel-header">
        <div class="title">
          <img src="https://lf-flow-web-cdn.doubao.com/obj/flow-doubao/favicon/new-doubao/64x64.png" width="22" height="22" style="border-radius:4px;flex-shrink:0;display:block" />
          <span class="title-text">豆包视频&amp;图片下载助手</span>
        </div>
        <button class="close-btn" id="db-close-btn" aria-label="关闭">&times;</button>
      </div>
      <div class="db-panel-tabs">
        <button data-tab="video" class="active" id="db-tab-video">
          <svg viewBox="0 0 24 24"><path d="M8 5v14l11-7z"/></svg>
          视频
          <span class="tab-count" id="db-tab-video-count">0</span>
        </button>
        <button data-tab="image" id="db-tab-image">
          <svg viewBox="0 0 24 24"><path d="M21 19V5a2 2 0 0 0-2-2H5a2 2 0 0 0-2 2v14a2 2 0 0 0 2 2h14a2 2 0 0 0 2-2zM8.5 13.5l2.5 3.01L14.5 12l4.5 6H5l3.5-4.5z"/></svg>
          图片
          <span class="tab-count" id="db-tab-image-count">0</span>
        </button>
      </div>
      <div class="db-panel-toolbar">
        <button id="db-scan-btn">
          <svg viewBox="0 0 24 24"><path d="M17.65 6.35A7.95 7.95 0 0 0 12 4a8 8 0 1 0 7.74 10h-2.08A6 6 0 1 1 12 6c1.66 0 3.14.69 4.22 1.78L13 11h7V4l-2.35 2.35z"/></svg>
          重新扫描
        </button>
        <button id="db-copyall-btn">
          <svg viewBox="0 0 24 24"><path d="M16 1H4a2 2 0 0 0-2 2v14h2V3h12V1zm3 4H8a2 2 0 0 0-2 2v14a2 2 0 0 0 2 2h11a2 2 0 0 0 2-2V7a2 2 0 0 0-2-2zm0 16H8V7h11v14z"/></svg>
          复制全部
        </button>
        <button class="primary" id="db-dlall-btn">
          <svg viewBox="0 0 24 24"><path d="M19 9h-4V3H9v6H5l7 7 7-7zM5 18v2h14v-2H5z"/></svg>
          下载全部
        </button>
      </div>
      <div class="db-panel-list" id="db-list-container"></div>
      <div class="db-disclaimer">
        免责声明：本脚本仅供学习和参考，切勿用于违法或商用，否则后果自负。
      </div>
    `;
    document.body.appendChild(panel);

    document.getElementById('db-close-btn').addEventListener('click', closePanel);
    document.getElementById('db-scan-btn').addEventListener('click', () => { scanPage(); showToast('扫描完成'); });
    document.getElementById('db-copyall-btn').addEventListener('click', copyAllLinks);
    document.getElementById('db-dlall-btn').addEventListener('click', downloadAll);
    document.getElementById('db-tab-video').addEventListener('click', () => switchTab('video'));
    document.getElementById('db-tab-image').addEventListener('click', () => switchTab('image'));

    renderActiveTab();
  }

  function switchTab(tab) {
    activeTab = tab;
    document.getElementById('db-tab-video').classList.toggle('active', tab === 'video');
    document.getElementById('db-tab-image').classList.toggle('active', tab === 'image');
    renderActiveTab();
  }

  function renderActiveTab() {
    const container = document.getElementById('db-list-container');
    if (!container) return;
    container.innerHTML = '';
    const items = Array.from(getActiveMap().values());
    if (items.length === 0) {
      container.innerHTML = `
        <div class="db-empty-state">
          <div class="icon-wrap">
            <svg viewBox="0 0 24 24"><path d="${activeTab === 'video' ? 'M18 4l2 4h-3l-2-4h-2l2 4h-3l-2-4H8l2 4H7L5 4H4a2 2 0 0 0-2 2v12a2 2 0 0 0 2 2h16a2 2 0 0 0 2-2V4h-4z' : 'M21 19V5a2 2 0 0 0-2-2H5a2 2 0 0 0-2 2v14a2 2 0 0 0 2 2h14a2 2 0 0 0 2-2zM8.5 13.5l2.5 3.01L14.5 12l4.5 6H5l3.5-4.5z'}"/></svg>
          </div>
          <span>暂无检测到${activeTab === 'video' ? '视频' : '图片'}</span>
          <span class="hint">${activeTab === 'video' ? '播放页面中的视频后将自动捕获' : '浏览页面或等待图片加载完成'}</span>
        </div>
      `;
      return;
    }
    items.forEach(item => addCard(null, item.type, item));
  }

  function addCard(key, type, preloadedItem) {
    const container = document.getElementById('db-list-container');
    if (!container) return;
    const emptyEl = container.querySelector('.db-empty-state');
    if (emptyEl) emptyEl.remove();

    const map = type === 'video' ? videoLinks : imageLinks;
    const item = preloadedItem || map.get(key);
    if (!item) return;
    const itemKey = key || [...map.entries()].find(([, value]) => value === item)?.[0] ||
      normalizeKey(item.downloadSrc || item.previewSrc || item.src);

    const card = document.createElement('div');
    card.className = type === 'video' ? 'db-video-card' : 'db-image-card';
    const previewSrc = item.previewSrc || item.src;
    card.dataset.src = previewSrc;
    card.dataset.download = item.downloadSrc || '';
    card.dataset.key = itemKey;

    const metaParts = [`<span class="badge-mini">${type === 'video' ? 'MP4' : 'IMG'}</span>`, `<span>${item.timestamp}</span>`];
    if (type === 'video' && item.resolution) metaParts.push(`<span class="dot"></span><span>${item.resolution}</span>`);
    if (type === 'video' && item.preparedBlob) metaParts.push(`<span class="dot"></span><span>无水印已准备</span>`);
    if (type === 'image' && item.sizeKb) metaParts.push(`<span class="dot"></span><span>${formatSize(item.sizeKb)}</span>`);

    card.innerHTML = `
      <button class="db-delete-btn" title="删除">
        <svg viewBox="0 0 24 24"><path d="M19 6.41L17.59 5 12 10.59 6.41 5 5 6.41 10.59 12 5 17.59 6.41 19 12 13.41 17.59 19 19 17.59 13.41 12z"/></svg>
      </button>
      <div class="db-card-row">
        <div class="db-thumb ${type === 'video' ? 'video' : 'image'}">
          <svg viewBox="0 0 24 24"><path d="${type === 'video' ? 'M8 5v14l11-7z' : 'M21 19V5a2 2 0 0 0-2-2H5a2 2 0 0 0-2 2v14a2 2 0 0 0 2 2h14a2 2 0 0 0 2-2zM8.5 13.5l2.5 3.01L14.5 12l4.5 6H5l3.5-4.5z'}"/></svg>
        </div>
        <div class="db-card-info">
          <div class="meta">${metaParts.join('')}</div>
          <div class="filename" title="${item.title}">${item.title}</div>
        </div>
      </div>
      <div class="db-card-actions">
        <button class="copy-btn">
          <svg viewBox="0 0 24 24"><path d="M16 1H4a2 2 0 0 0-2 2v14h2V3h12V1zm3 4H8a2 2 0 0 0-2 2v14a2 2 0 0 0 2 2h11a2 2 0 0 0 2-2V7a2 2 0 0 0-2-2zm0 16H8V7h11v14z"/></svg>
          复制
        </button>
        <button class="dl-btn">
          <svg viewBox="0 0 24 24"><path d="M19 9h-4V3H9v6H5l7 7 7-7zM5 18v2h14v-2H5z"/></svg>
          ${type === 'video' ? (item.preparedBlob ? '保存' : '准备视频') : '下载'}
        </button>
      </div>
    `;

    card.querySelector('.copy-btn').addEventListener('click', function () {
      copyItemLink(item, this);
    });
    card.querySelector('.dl-btn').addEventListener('click', function () {
      downloadFile(item, item.title);
    });
    card.querySelector('.db-delete-btn').addEventListener('click', function (e) {
      e.stopPropagation();
      deleteCard(itemKey, type, card);
    });
    card.addEventListener('click', function (e) {
      if (e.target.closest('.db-card-actions') || e.target.closest('.db-delete-btn')) return;
      openPreview(previewSrc, type, previewSrc);
    });

    loadThumb(card.querySelector('.db-thumb'), previewSrc, type);

    container.insertBefore(card, container.firstChild);
    updateCounts();
  }

  function deleteCard(key, type, cardEl) {
    if (!cardEl) return;
    cardEl.style.animation = 'db-card-out 0.3s ease forwards';
    setTimeout(() => {
      cardEl.remove();
      if (type === 'video') {
        videoLinks.delete(key);
        processedVideoSrcs.delete(key);
      } else {
        imageLinks.delete(key);
        processedImageSrcs.delete(key);
      }
      updateCounts();
      updateBadge();
      const container = document.getElementById('db-list-container');
      if (container && container.children.length === 0) renderActiveTab();
      showToast('已删除');
    }, 280);
  }

  function loadThumb(thumbEl, src, type) {
    if (type === 'image') {
      const img = document.createElement('img');
      img.crossOrigin = 'anonymous';
      img.referrerPolicy = 'no-referrer';
      img.onload = () => {
        thumbEl.innerHTML = '';
        thumbEl.appendChild(img);
      };
      img.onerror = () => {};
      img.src = src;
    } else {
      // 视频：先用 canvas 截取第一帧
      const video = document.createElement('video');
      video.src = src;
      video.crossOrigin = 'anonymous';
      video.preload = 'metadata';
      video.muted = true;
      video.style.cssText = 'width:100%;height:100%;object-fit:cover;';

      let thumbLoaded = false;

      video.addEventListener('loadeddata', () => {
        try { video.currentTime = Math.min(0.1, video.duration * 0.05); }
        catch (e) {}
      });

      video.addEventListener('seeked', () => {
        if (thumbLoaded) return;
        thumbLoaded = true;
        try {
          const canvas = document.createElement('canvas');
          canvas.width = 160;
          canvas.height = 90;
          const ctx = canvas.getContext('2d');
          ctx.drawImage(video, 0, 0, canvas.width, canvas.height);
          const img = document.createElement('img');
          img.src = canvas.toDataURL('image/jpeg', 0.7);
          img.style.cssText = 'width:100%;height:100%;object-fit:cover;';
          thumbEl.innerHTML = '';
          thumbEl.appendChild(img);
        } catch (e) {}
        cleanup();
      });

      video.addEventListener('error', () => {
        if (thumbLoaded) return;
        thumbLoaded = true;
        cleanup();
      });

      function cleanup() {
        try { video.pause(); video.removeAttribute('src'); video.load(); } catch (e) {}
      }

      // 兜底：2秒后还没加载就用 img 标签加载视频 URL（部分浏览器支持）
      setTimeout(() => {
        if (thumbLoaded) return;
        thumbLoaded = true;
        const img = document.createElement('img');
        img.crossOrigin = 'anonymous';
        img.referrerPolicy = 'no-referrer';
        img.style.cssText = 'width:100%;height:100%;object-fit:cover;';
        img.onload = () => {
          if (img.naturalWidth > 0) {
            thumbEl.innerHTML = '';
            thumbEl.appendChild(img);
          }
        };
        img.src = src;
      }, 2500);
    }
  }

  function openPreview(src, type, title) {
    let modal = document.getElementById('db-preview-modal');
    if (!modal) {
      modal = document.createElement('div');
      modal.id = 'db-preview-modal';
      modal.innerHTML = `
        <button class="preview-close" aria-label="关闭">&times;</button>
        <div class="preview-content"></div>
        <div class="preview-info"></div>
      `;
      document.body.appendChild(modal);
      modal.addEventListener('click', (e) => {
        if (e.target === modal) closePreview();
      });
      modal.querySelector('.preview-close').addEventListener('click', closePreview);
    }
    const content = modal.querySelector('.preview-content');
    const info = modal.querySelector('.preview-info');
    content.innerHTML = '';
    info.textContent = title || '';

    if (type === 'video') {
      const video = document.createElement('video');
      video.src = src;
      video.controls = true;
      video.autoplay = true;
      video.style.cssText = 'max-width:92vw;max-height:88vh;';
      content.appendChild(video);
    } else {
      const img = document.createElement('img');
      img.src = src;
      img.alt = title || '';
      content.appendChild(img);
    }

    modal.classList.add('show');
  }

  function closePreview() {
    const modal = document.getElementById('db-preview-modal');
    if (!modal) return;
    modal.classList.remove('show');
    const content = modal.querySelector('.preview-content');
    if (content) {
      content.querySelectorAll('video').forEach(v => { try { v.pause(); v.removeAttribute('src'); v.load(); } catch (e) {} });
      content.innerHTML = '';
    }
  }

  function updateCounts() {
    const videoCount = document.getElementById('db-tab-video-count');
    const imageCount = document.getElementById('db-tab-image-count');
    if (!videoCount || !imageCount) return;
    const vc = videoLinks.size;
    const ic = imageLinks.size;
    videoCount.textContent = vc;
    imageCount.textContent = ic;
  }

  function updateBadge() {
    const badge = document.querySelector('#db-dl-btn .badge');
    if (!badge) return;
    const total = videoLinks.size + imageLinks.size;
    if (total === 0) {
      badge.classList.add('hidden');
      badge.classList.remove('pulse');
    } else {
      badge.classList.remove('hidden');
      badge.style.display = 'block';
      badge.classList.remove('pulse');
      void badge.offsetWidth;
      badge.classList.add('pulse');
    }
  }

  function togglePanel() {
    const panel = document.getElementById('db-dl-panel');
    if (panel.classList.contains('open')) closePanel(); else openPanel();
  }
  function openPanel() {
    document.getElementById('db-dl-panel').classList.add('open');
    document.getElementById('db-dl-overlay').classList.add('show');
    document.body.style.overflow = 'hidden';
    renderActiveTab();
    updateCounts();
  }
  function closePanel() {
    document.getElementById('db-dl-panel').classList.remove('open');
    document.getElementById('db-dl-overlay').classList.remove('show');
    document.body.style.overflow = '';
  }

  async function copyToClipboard(text, btnEl) {
    const originalHTML = btnEl.innerHTML;
    try {
      await navigator.clipboard.writeText(text);
      if (btnEl) {
        btnEl.classList.add('copied');
        btnEl.textContent = '✓ 已复制';
        setTimeout(() => { btnEl.classList.remove('copied'); btnEl.innerHTML = originalHTML; }, 1800);
      }
      showToast('链接已复制');
    } catch (e) {
      const ta = document.createElement('textarea');
      ta.value = text;
      ta.style.cssText = 'position:fixed;left:-9999px;';
      document.body.appendChild(ta);
      ta.select();
      document.execCommand('copy');
      document.body.removeChild(ta);
      showToast('链接已复制');
    }
  }

  async function copyItemLink(item, btnEl) {
    try {
      const url = await resolveDownloadUrl(item);
      await copyToClipboard(url, btnEl);
    } catch (error) {
      showToast(error.message || '获取无水印链接失败', 3200);
    }
  }

  async function copyAllLinks() {
    const map = getActiveMap();
    if (map.size === 0) { showToast('没有可复制的链接'); return; }
    const urls = [];
    let failed = 0;
    for (const item of map.values()) {
      try {
        urls.push(await resolveDownloadUrl(item));
      } catch (error) {
        failed++;
      }
    }
    if (urls.length === 0) {
      showToast('没有可复制的无水印链接', 3200);
      return;
    }
    await copyToClipboard(urls.join('\n'), null);
    showToast(failed ? `已复制 ${urls.length} 个链接，${failed} 个获取失败` : `已复制 ${urls.length} 个无水印链接`);
  }

  function safeFilename(filename, type) {
    const fallback = type === 'video' ? 'doubao_video.mp4' : 'doubao_image.png';
    let name = String(filename || fallback)
      .replace(/[<>:"/\\|?*\u0000-\u001f]/g, '_')
      .replace(/^\.+|\.+$/g, '')
      .slice(0, 180) || fallback;
    if (type === 'video' && !/\.(mp4|webm|mov)$/i.test(name)) name += '.mp4';
    if (type === 'image' && !/\.(png|jpe?g|webp|gif|bmp)$/i.test(name)) name += '.png';
    return name;
  }

  function triggerAnchorDownload(url, filename) {
    const a = document.createElement('a');
    a.href = url;
    a.download = filename;
    a.rel = 'noopener noreferrer';
    a.style.display = 'none';
    document.body.appendChild(a);
    a.click();
    setTimeout(() => a.remove(), 200);
  }

  function saveBlob(blob, filename) {
    if (!blob || !blob.size) throw new Error('下载文件为空');
    const blobUrl = URL.createObjectURL(blob);
    triggerAnchorDownload(blobUrl, filename);
    setTimeout(() => URL.revokeObjectURL(blobUrl), 60000);
  }

  async function downloadViaPageFetch(url, filename) {
    const response = await pageWindow.fetch(url, { credentials: 'omit', cache: 'no-store' });
    if (!response.ok) throw new Error(`原图请求失败：HTTP ${response.status}`);
    const blob = await response.blob();
    saveBlob(blob, filename);
  }

  function downloadBlobViaGM(url, timeoutMs, onProgress) {
    return new Promise((resolve, reject) => {
      if (typeof GM_xmlhttpRequest !== 'function') {
        reject(new Error('GM_xmlhttpRequest 不可用'));
        return;
      }
      GM_xmlhttpRequest({
        method: 'GET',
        url,
        responseType: 'blob',
        timeout: timeoutMs || 180000,
        onprogress: progress => {
          if (typeof onProgress === 'function') onProgress(progress);
        },
        onload: response => {
          try {
            if (response.status < 200 || response.status >= 300) {
              throw new Error(`文件下载失败：HTTP ${response.status}`);
            }
            let blob = response.response;
            if (blob instanceof ArrayBuffer) {
              blob = new Blob([blob], { type: 'application/octet-stream' });
            }
            if (!blob || !blob.size) throw new Error('下载文件为空');
            resolve(blob);
          } catch (error) {
            reject(error);
          }
        },
        onerror: error => reject(error || new Error('文件下载失败')),
        ontimeout: () => reject(new Error('下载超时'))
      });
    });
  }

  async function prepareVideoBlob(item, url, filename) {
    let lastProgressAt = 0;
    try {
      item.preparedBlob = await downloadBlobViaGM(url, 180000, progress => {
        const now = Date.now();
        if (now - lastProgressAt < 700 || !progress.total) return;
        lastProgressAt = now;
        const percent = Math.min(100, Math.round(progress.loaded / progress.total * 100));
        showToast(`正在准备无水印视频 ${percent}%`, 1600);
      });
    } catch (gmRequestError) {
      throw gmRequestError;
    }
    item.preparedName = filename;
    scheduleMediaRefresh();
  }

  async function downloadFile(item, filename) {
    const name = safeFilename(filename || item.title, item.type);
    if (item.type === 'video' && item.preparedBlob) {
      const blob = item.preparedBlob;
      item.preparedBlob = null;
      item.preparedName = '';
      saveBlob(blob, name);
      scheduleMediaRefresh();
      showToast(`已开始保存：${name}`, 2600);
      return true;
    }

    showToast(item.type === 'video' ? '正在获取无水印视频地址…' : '正在准备原图…', 2400);
    try {
      const url = await resolveDownloadUrl(item);
      if (item.type === 'video') {
        await prepareVideoBlob(item, url, name);
        showToast('无水印视频已准备好，请再点一次“保存”', 6000);
        return true;
      }
      try {
        await downloadViaPageFetch(url, name);
      } catch (pageFetchError) {
        console.debug('[豆包下载助手] 页面 Blob 下载失败，尝试扩展下载', pageFetchError);
        const blob = await downloadBlobViaGM(url, 60000);
        saveBlob(blob, name);
      }
      showToast(`开始下载：${name}`, 2400);
      return true;
    } catch (error) {
      showToast(error?.message || error?.error || '下载失败', 3500);
      return false;
    }
  }

  async function downloadAll() {
    const map = getActiveMap();
    if (map.size === 0) { showToast('没有可下载的资源'); return; }
    const items = Array.from(map.values());
    let failed = 0;
    let preparedVideos = 0;
    for (let index = 0; index < items.length; index++) {
      showToast(`正在处理 ${index + 1}/${items.length}（仅下载无水印原文件）`, 2400);
      const ok = await downloadFile(items[index], items[index].title);
      if (!ok) failed++;
      if (ok && items[index].preparedBlob) preparedVideos++;
      if (index < items.length - 1) await new Promise(resolve => setTimeout(resolve, 700));
    }
    if (preparedVideos > 0) {
      showToast(`已准备 ${preparedVideos} 个无水印视频，请逐个点击“保存”`, 6000);
    } else {
      showToast(failed ? `批量下载完成，${failed} 个资源失败` : `已开始下载 ${items.length} 个无水印资源`, 3200);
    }
  }

  function setupDrag(btn) {
    let isDragging = false;
    let startX, startY, startRight, startBottom;
    let moved = false;

    const onStart = (e) => {
      if (e.button !== 0) return;
      isDragging = true;
      moved = false;
      startX = e.clientX;
      startY = e.clientY;
      const rect = btn.getBoundingClientRect();
      startRight = window.innerWidth - rect.right;
      startBottom = window.innerHeight - rect.bottom;
      btn.style.transition = 'none';
      document.body.style.userSelect = 'none';
    };

    const onMove = (e) => {
      if (!isDragging) return;
      const dx = e.clientX - startX;
      const dy = e.clientY - startY;
      if (Math.abs(dx) > 3 || Math.abs(dy) > 3) moved = true;
      const newRight = Math.max(0, Math.min(window.innerWidth - 48, startRight - dx));
      const newBottom = Math.max(0, Math.min(window.innerHeight - 48, startBottom - dy));
      btn.style.right = newRight + 'px';
      btn.style.bottom = newBottom + 'px';
    };

    const onEnd = () => {
      if (!isDragging) return;
      isDragging = false;
      btn.style.transition = '';
      document.body.style.userSelect = '';
      if (moved) {
        savePosition(btn);
        btn._suppressClick = true;
        setTimeout(() => { btn._suppressClick = false; }, 50);
      }
    };

    btn.addEventListener('mousedown', onStart);
    document.addEventListener('mousemove', onMove);
    document.addEventListener('mouseup', onEnd);

    btn.addEventListener('click', (e) => {
      if (btn._suppressClick) { e.stopImmediatePropagation(); e.preventDefault(); }
    }, true);

    btn.addEventListener('touchstart', (e) => {
      const t = e.touches[0];
      onStart({ button: 0, clientX: t.clientX, clientY: t.clientY });
    }, { passive: true });
    btn.addEventListener('touchmove', (e) => {
      const t = e.touches[0];
      onMove({ clientX: t.clientX, clientY: t.clientY });
    }, { passive: true });
    btn.addEventListener('touchend', onEnd);
  }

  function savePosition(btn) {
    try {
      const rect = btn.getBoundingClientRect();
      localStorage.setItem('db-dl-btn-pos', JSON.stringify({
        right: window.innerWidth - rect.right,
        bottom: window.innerHeight - rect.bottom
      }));
    } catch (e) {}
  }

  function restorePosition(btn) {
    try {
      const saved = localStorage.getItem('db-dl-btn-pos');
      if (saved) {
        const pos = JSON.parse(saved);
        if (typeof pos.right === 'number') btn.style.right = pos.right + 'px';
        if (typeof pos.bottom === 'number') btn.style.bottom = pos.bottom + 'px';
      }
    } catch (e) {}
  }

  function setupKeyboard() {
    document.addEventListener('keydown', (e) => {
      if (e.ctrlKey && e.shiftKey && e.key === 'D') { e.preventDefault(); togglePanel(); }
      if (e.key === 'Escape') {
        const modal = document.getElementById('db-preview-modal');
        if (modal && modal.classList.contains('show')) {
          closePreview();
          return;
        }
        const panel = document.getElementById('db-dl-panel');
        if (panel && panel.classList.contains('open')) closePanel();
      }
    });
  }

  function init() {
    buildUI();
    setupKeyboard();
    scanEmbeddedData();
    setTimeout(scanPage, 300);
    setupPerformanceObserver();
    setupObserver();
    setInterval(scanPage, 2000);
    console.log('[豆包下载助手] v5.1.5 已启动，图片与视频均使用无水印原文件，快捷键 Ctrl+Shift+D');
    console.debug('[豆包下载助手] GM_xmlhttpRequest:', typeof GM_xmlhttpRequest);
  }

  installDataHooks();

  if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', () => setTimeout(init, 300), { once: true });
  } else {
    setTimeout(init, 300);
  }
})();