ndjsxh
/
study_sm


			
				
					
						
						
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							<!DOCTYPE html>
<html lang="zh-CN">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>视频播放 - 宁德市建筑业协会</title>
  <script src="/static/js/hls.min.js"></script>
  <script src="/static/js/md5.min.js"></script>
  <style>
    * { margin: 0; padding: 0; box-sizing: border-box; }
    body {
      font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
      background: #f0f2f5;
      min-height: 100vh;
    }
    .pc-player-container {
      min-height: 100vh;
      background: #f0f2f5;
      padding: 20px;
    }
    .pc-player-wrapper {
      max-width: 1440px;
      margin: 0 auto;
      display: flex;
      gap: 20px;
      height: calc(100vh - 40px);
    }
    .pc-player-left { flex: 1; min-width: 0; display: flex; flex-direction: column; }
    .panel-toggle {
      flex-shrink: 0; width: 20px; display: flex; align-items: center; justify-content: center;
      cursor: pointer; color: #999; font-size: 14px; user-select: none;
    }
    .panel-toggle:hover { color: #409EFF; }
    .video-section {
      background: #fff; border-radius: 12px; box-shadow: 0 2px 12px rgba(0,0,0,0.08); overflow: hidden;
      display: flex; flex-direction: column; height: 100%;
    }
    .video-title {
      padding: 16px 20px; font-size: 16px; font-weight: 600; color: #1a1a2e;
      border-bottom: 1px solid #f0f0f0; white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
      flex-shrink: 0;
    }
    .video-player-wrap {
      width: 100%; background: #000; position: relative; flex: 1; min-height: 0;
      display: flex; align-items: center; justify-content: center;
    }
    .video-player-wrap video {
      width: 100%; height: 100%; display: block; outline: none;
      max-height: calc(100vh - 200px);
    }
    .loading-overlay {
      position: absolute; inset: 0; display: flex; align-items: center; justify-content: center;
      background: rgba(0,0,0,0.5); color: #fff; font-size: 16px; z-index: 10;
      transition: opacity .3s;
    }
    .loading-overlay.hidden { opacity: 0; pointer-events: none; }
    .loading-spinner { width: 40px; height: 40px; border: 3px solid rgba(255,255,255,.3); border-top-color: #fff; border-radius: 50%; animation: spin .8s linear infinite; margin-right: 12px; }
    @keyframes spin { to { transform: rotate(360deg); } }
    .dialog-footer {
      padding: 8px 16px; border-top: 1px solid #f0f0f0; background: #fafafa; flex-shrink: 0;
    }
    .media-footer { display: flex; align-items: center; line-height: 1; }
    .media-time {
      font-size: 14px; color: #666; white-space: nowrap; font-variant-numeric: tabular-nums;
      display: flex; align-items: center; gap: 4px;
    }
    .media-center { display: flex; align-items: center; justify-content: center; gap: 12px; flex:1; }
    .btn-icon {
      display: inline-flex; align-items: center; gap: 4px; font-size: 12px; font-weight: 600;
      cursor: pointer; user-select: none; padding: 4px 8px; border: 1px solid #dcdfe6;
      border-radius: 4px; color: #606266; background: #fff; transition: all .2s;
    }
    .btn-icon:hover { color: #409EFF; border-color: #c6e2ff; background: #ecf5ff; }
    .btn-icon.is-active { color: #409EFF; border-color: #409EFF; background: #ecf5ff; }
    .volume-group { display: inline-flex; align-items: center; gap: 6px; }
    .volume-slider { width: 100px; height: 4px; -webkit-appearance: none; appearance: none; background: #dcdfe6; border-radius: 2px; outline: none; }
    .volume-slider::-webkit-slider-thumb { -webkit-appearance: none; width: 12px; height: 12px; border-radius: 50%; background: #409EFF; cursor: pointer; }
    .quality-select {
      height: 28px; font-size: 12px; padding: 0 8px; border: 1px solid #dcdfe6;
      border-radius: 4px; outline: none; color: #606266; background: #fff; cursor: pointer;
    }
    .quality-select:focus { border-color: #409EFF; }

    .pc-player-right {
      width: 380px; flex-shrink: 0; background: #fff; border-radius: 12px;
      box-shadow: 0 2px 12px rgba(0,0,0,0.08); display: flex; flex-direction: column; overflow: hidden;
    }
    .playlist-header {
      padding: 16px 20px 12px; border-bottom: 1px solid #f0f0f0; flex-shrink: 0;
    }
    .playlist-title { font-size: 16px; font-weight: 600; color: #1a1a2e; }
    .playlist-header-row {
      display: flex; align-items: center; justify-content: space-between; margin-top: 6px;
    }
    .playlist-count { font-size: 12px; color: #999; }
    .finished-count { color: #67C23A; }
    .hide-toggle { display: flex; align-items: center; gap: 6px; font-size: 12px; cursor: pointer; color: #666; user-select: none; }
    .hide-toggle input { cursor: pointer; }
    .playlist-body { flex: 1; overflow-y: auto; padding: 8px 0; }
    .playlist-body::-webkit-scrollbar { width: 6px; }
    .playlist-body::-webkit-scrollbar-thumb { background: #ddd; border-radius: 3px; }
    .playlist-item {
      display: flex; align-items: center; padding: 12px 20px; cursor: pointer;
      transition: all .2s; border-left: 3px solid transparent; gap: 12px;
    }
    .playlist-item:hover { background: #f5f7fa; }
    .playlist-item.is-active { background: #ecf5ff; border-left-color: #409EFF; }
    .playlist-item.is-finished { opacity: .65; }
    .item-index {
      width: 28px; height: 28px; border-radius: 50%; background: #f0f2f5;
      display: flex; align-items: center; justify-content: center; font-size: 12px;
      font-weight: 600; color: #666; flex-shrink: 0;
    }
    .item-index.active-index { background: #409EFF; color: #fff; }
    .finish-badge { color: #67C23A; font-size: 14px; }
    .item-info { flex: 1; min-width: 0; }
    .item-name { font-size: 14px; color: #333; font-weight: 500; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; margin-bottom: 2px; }
    .is-finished .item-name { color: #999; text-decoration: line-through; }
    .is-active .item-name { color: #409EFF; }
    .item-meta { display: flex; gap: 12px; font-size: 12px; color: #999; }
    .item-progress { color: #409EFF; }
    .is-finished .item-progress { color: #67C23A; }
    .item-action { flex-shrink: 0; }
    .play-btn {
      padding: 4px 10px; font-size: 12px; border: 1px solid #409EFF; color: #409EFF;
      background: transparent; border-radius: 4px; cursor: pointer; transition: all .2s;
    }
    .play-btn:hover { background: #409EFF; color: #fff; }
    .play-btn.pause-btn { background: #e6a23c; border-color: #e6a23c; color: #fff; }
    .playlist-empty { text-align: center; padding: 60px 20px; color: #ccc; font-size: 14px; }

    .toast {
      position: fixed; top: 20px; left: 50%; transform: translateX(-50%); z-index: 9999;
      padding: 10px 24px; border-radius: 6px; font-size: 14px; color: #fff;
      transition: all .3s; opacity: 0; pointer-events: none;
    }
    .toast.show { opacity: 1; }
    .toast.success { background: #67C23A; }
    .toast.error { background: #F56C6C; }
    .toast.info { background: #909399; }

    @media (max-width: 900px) {
      .pc-player-wrapper { flex-direction: column; height: auto; }
      .pc-player-right { width: 100%; max-height: 400px; }
      .pc-player-container { padding: 12px; }
      .volume-slider { width: 60px; }
    }
  </style>
</head>
<body>
  <div class="pc-player-container">
    <div class="pc-player-wrapper">
      <div class="pc-player-left">
        <div class="video-section">
          <div class="video-title" id="videoTitle">加载中...</div>
          <div class="video-player-wrap">
            <video id="videoElement" playsinline preload="auto"></video>
            <div class="loading-overlay" id="loadingOverlay">
              <div class="loading-spinner"></div>
              <span>加载中...</span>
            </div>
          </div>
          <div class="dialog-footer">
            <div class="media-footer">
              <div class="media-time">
                <span id="currentTime">00:00:00</span>
                <strong>/</strong>
                <span id="totalTime">00:00:00</span>
              </div>
              <div class="media-center">
                <span class="volume-group">
                  <span class="btn-icon" id="muteBtn">音量</span>
                  <input type="range" class="volume-slider" id="volumeSlider" min="0" max="1" step="0.05" value="0.5">
                </span>
                <span class="btn-icon" id="pipBtn">画中画</span>
              </div>
              <div style="display:flex;align-items:center;justify-content:flex-end;flex:1;">
                <select class="quality-select" id="qualitySelect">
                  <option value="ld">流畅</option>
                  <option value="hls" selected>标清</option>
                </select>
              </div>
            </div>
          </div>
        </div>
      </div>

      <div class="panel-toggle" id="panelToggle">&lt;</div>

      <div class="pc-player-right" id="playlistPanel">
        <div class="playlist-header">
          <div class="playlist-title">课程列表</div>
          <div class="playlist-header-row">
            <div class="playlist-count">
              共 <span id="totalCount">0</span> 个视频
              <span class="finished-count" id="finishedCountWrap" style="display:none;">，已完成 <span id="finishedCount">0</span> 个</span>
            </div>
            <label class="hide-toggle">
              <input type="checkbox" id="hideFinishedCheck"> 隐藏已完成
            </label>
          </div>
        </div>
        <div class="playlist-body" id="playlistBody"></div>
      </div>
    </div>
  </div>

  <div class="toast" id="toast"></div>

  <script>
    const VERSION = '1.0';
    const SECRET = '017c0743819088468e590246464cc75f';
    const API_BASE = 'https://ndapi.hqedust.com:18443/rental';

    // ---- DOM refs ----
    const video = document.getElementById('videoElement');
    const loadingOverlay = document.getElementById('loadingOverlay');
    const videoTitle = document.getElementById('videoTitle');
    const currentTimeEl = document.getElementById('currentTime');
    const totalTimeEl = document.getElementById('totalTime');
    const volumeSlider = document.getElementById('volumeSlider');
    const muteBtn = document.getElementById('muteBtn');
    const pipBtn = document.getElementById('pipBtn');
    const qualitySelect = document.getElementById('qualitySelect');
    const panelToggle = document.getElementById('panelToggle');
    const playlistPanel = document.getElementById('playlistPanel');
    const playlistBody = document.getElementById('playlistBody');
    const totalCount = document.getElementById('totalCount');
    const finishedCount = document.getElementById('finishedCount');
    const finishedCountWrap = document.getElementById('finishedCountWrap');
    const hideFinishedCheck = document.getElementById('hideFinishedCheck');
    const toast = document.getElementById('toast');

    // ---- state ----
    let uid = 0, token = '', courseId = 0, mediaId = 0;
    let mediaList = [];
    let currentMedia = null;
    let currentMediaUrl = '';
    let isPlaying = false;
    let isMuted = false;
    let volume = 0.5;
    let curTimes = 0;
    let tickTimer = null;
    let tickNum = 0;
    let hasSeeked = false;
    let hiddenStartTime = 0;
    let hiddenBasePosition = 0;
    let isPiP = false;
    let hls = null;
    let showPanel = true;

    // ---- utils ----
    function parseTime(seconds) {
      seconds = parseInt(seconds) || 0;
      const h = String(Math.floor(seconds / 3600)).padStart(2, '0');
      const m = String(Math.floor((seconds % 3600) / 60)).padStart(2, '0');
      const s = String(seconds % 60).padStart(2, '0');
      return h + ':' + m + ':' + s;
    }

    function getPercent(item) {
      if (item.isFinish == 1) return 100;
      if (!item.duration) return 0;
      let p = parseInt((item.position || 0) * 10000 / item.duration) / 100;
      return p >= 100 ? 99.99 : p;
    }

    function showToast(msg, type, duration) {
      toast.textContent = msg;
      toast.className = 'toast ' + type + ' show';
      clearTimeout(toast._timer);
      toast._timer = setTimeout(() => toast.classList.remove('show'), duration || 3000);
    }

    // ---- API ----
    function signRequest(method, data) {
      const body = JSON.stringify(data);
      const mtime = Math.floor(Date.now() / 1000);
      const raw = 'hall_' + VERSION + token + body + method + mtime + SECRET;
      const sign = md5(raw);
      const u = method.startsWith('Auth.') ? '0' : (uid || 0);
      return API_BASE + '/' + method + '?t=' + mtime + '&u=' + u + '&v=' + VERSION + '&s=' + sign;
    }

    async function api(method, data) {
      const url = signRequest(method, data);
      const res = await fetch(url, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(data)
      });
      const json = await res.json();
      if (json.code === 401) {
        showToast('用户被踢下线，请重新登入', 'error', 5000);
        return json;
      }
      if (json.code !== 200) {
        showToast(json.msg || '请求失败', 'error');
      }
      return json;
    }

    function report(action, msg) {
      api('course.report', { action, msg });
    }

    // ---- player ----
    function loadVideo(src, position) {
      if (hls) {
        hls.destroy();
        hls = null;
      }
      video.removeAttribute('src');

      if (Hls.isSupported()) {
        hls = new Hls({
          enableWorker: true,
          xhrSetup: function(xhr) {
            xhr.setRequestHeader('Cache-Control', 'no-cache, no-store, must-revalidate');
            xhr.setRequestHeader('Pragma', 'no-cache');
          }
        });
        hls.loadSource(src);
        hls.attachMedia(video);
        hls.on(Hls.Events.MANIFEST_PARSED, function() {
          loadingOverlay.classList.add('hidden');
          if (position > 0) {
            video.currentTime = position;
          }
          safePlay();
        });
        hls.on(Hls.Events.ERROR, function(e, data) {
          if (data.fatal) {
            showToast('视频加载失败，尝试切换清晰度', 'error');
          }
        });
      } else if (video.canPlayType('application/vnd.apple.mpegurl')) {
        video.src = src;
        video.addEventListener('loadedmetadata', function() {
          loadingOverlay.classList.add('hidden');
          if (position > 0) video.currentTime = position;
          safePlay();
        }, { once: true });
      } else {
        showToast('您的浏览器不支持 HLS 播放', 'error');
      }
    }

    function safePlay() {
      const p = video.play();
      if (p && p.catch) p.catch(function() {});
    }

    function setVolume(val) {
      volume = Math.max(0, Math.min(1, val));
      video.volume = volume;
      video.muted = isMuted;
      volumeSlider.value = volume;
      muteBtn.textContent = volume === 0 || isMuted ? '静音' : '音量';
    }

    function setPosition(pos) {
      if (pos < 10) return;
      if (pos > (currentMedia ? currentMedia.duration : Infinity)) pos = currentMedia.duration;
      video.currentTime = pos;
      safePlay();
      if (currentMedia && currentMedia.isFinish) return;
      if (currentMedia && currentMedia.position >= currentMedia.duration - 10 && !currentMedia.isFinish) {
        tick(true);
      }
    }

    // ---- course loading ----
    async function loadCourse() {
      const res = await api('course.getCourse', { courseId });
      if (res.code !== 200) return;
      const { info, extra, list, tpl } = res.data;
      const courseInfo = Object.assign(info || {}, extra || {});
      mediaList = (list || []).map(function(item) {
        item.percent = getPercent(item);
        return item;
      });
      updatePlaylist();

      let target = null;
      if (mediaId) {
        target = mediaList.find(function(i) { return i.id == mediaId || i.mediaId == mediaId; });
      }
      if (!target) target = mediaList.find(function(i) { return i.isFinish != 1; });
      if (!target && mediaList.length) target = mediaList[0];
      if (target) {
        loadMedia(target);
      } else {
        videoTitle.textContent = (tpl || {}).name || '暂无视频';
      }
    }

    async function loadMedia(item) {
      currentMedia = item;
      videoTitle.textContent = item.name;
      loadingOverlay.classList.remove('hidden');
      hasSeeked = false;
      isPlaying = false;
      stopTick();

      const res = await api('course.GetMedia', { id: item.id });
      if (res.code !== 200) {
        loadingOverlay.classList.add('hidden');
        return;
      }
      const data = res.data || {};
      let mediaUrl = data.mediaUrl || '';
      const position = (data.position || 0) < 10 ? 0 : (data.position || 0);
      const duration = data.duration || 0;

      currentMediaUrl = mediaUrl;
      currentMedia.position = position;
      currentMedia.duration = duration;
      currentMedia.id = data.id || item.id;

      qualitySelect.value = mediaUrl.includes('/ld/') ? 'ld' : 'hls';

      curTimes = 0;
      loadVideo(mediaUrl, position);
      startTick();
      updatePlaylist();
      report('play', 'start');
    }

    function changeMedia(quality) {
      if (!currentMediaUrl) return;
      let url = currentMediaUrl;
      if (quality === 'ld') {
        url = url.replace('/hls/', '/ld/');
      } else {
        url = url.replace('/ld/', '/hls/');
      }
      currentMediaUrl = url;
      const pos = video.currentTime || 0;
      loadVideo(url, pos > 0 ? pos : 0);
    }

    // ---- tick system ----
    function startTick() {
      stopTick();
      tickTimer = setInterval(tryTick, 5000);
    }

    function stopTick() {
      if (tickTimer) {
        clearInterval(tickTimer);
        tickTimer = null;
      }
    }

    function getPlayerTime() {
      if (hiddenStartTime) {
        const elapsed = (Date.now() - hiddenStartTime) / 1000;
        const estimated = hiddenBasePosition + elapsed;
        const actual = video.currentTime || 0;
        if (actual >= estimated - 0.5) {
          hiddenStartTime = 0;
          return actual;
        }
        return Math.min(estimated, currentMedia ? currentMedia.duration : Infinity);
      }
      return video.currentTime || 0;
    }

    function tryTick() {
      try { doTick(); } catch (e) { report('play', '' + e.message); }
    }

    async function doTick(force) {
      if (!currentMedia || currentMedia.isFinish) return;
      tickNum++;
      const ct = Math.floor(getPlayerTime());
      curTimes = ct;

      if (navigator.webdriver) {
        report('play', 'webdriver');
        doPause();
        return;
      }

      let isFinish = force ? 1 : 0;
      if (ct >= currentMedia.duration) isFinish = 1;

      const res = await api('course.tick', {
        id: currentMedia.id,
        position: ct,
        isFinish: isFinish
      });
      if (res.code !== 200) return;
      const d = res.data || {};
      if (d.closed) {
        doPause();
        showToast(d.msg || '课程已关闭', 'error', 10000);
        return;
      }
      if (d.pause) {
        doPause();
        showToast(d.msg || '已暂停', 'info', 10000);
        setTimeout(async function() {
          await loadCourse();
        }, 30000);
        return;
      }
      if (!d.skip) {
        setPosition(d.position || 0);
      }
      Object.assign(currentMedia, d);
      if (d.isFinish == 1) {
        updatePlaylist();
        await new Promise(r => setTimeout(r, 1000));
        playNext();
      }
      updatePlaylist();
    }

    function tick(force) {
      doTick(force);
    }

    // ---- playlist ----
    function updatePlaylist() {
      const finished = mediaList.filter(function(i) { return i.isFinish == 1; }).length;
      totalCount.textContent = mediaList.length;
      if (finished > 0) {
        finishedCountWrap.style.display = 'inline';
        finishedCount.textContent = finished;
      } else {
        finishedCountWrap.style.display = 'none';
      }

      const hide = hideFinishedCheck.checked;
      const filtered = hide ? mediaList.filter(function(i) { return i.isFinish != 1; }) : mediaList;

      playlistBody.innerHTML = '';
      filtered.forEach(function(item, idx) {
        const div = document.createElement('div');
        div.className = 'playlist-item';
        if (currentMedia && currentMedia.id === item.id) div.classList.add('is-active');
        if (item.isFinish == 1) div.classList.add('is-finished');

        const isCurrent = currentMedia && currentMedia.id === item.id;
        const origIdx = mediaList.indexOf(item);

        div.innerHTML =
          '<div class="item-index' + (isCurrent ? ' active-index' : '') + '">' +
            (item.isFinish == 1 ? '<span class="finish-badge">&#10003;</span>' : '<span>' + (origIdx + 1) + '</span>') +
          '</div>' +
          '<div class="item-info">' +
            '<div class="item-name">' + item.name + '</div>' +
            '<div class="item-meta">' +
              '<span>学时：' + (item.xs / 10) + '</span>' +
              '<span class="item-progress">' + getPercent(item) + '%</span>' +
            '</div>' +
          '</div>' +
          '<div class="item-action">' +
            (isCurrent && isPlaying
              ? '<button class="play-btn pause-btn" data-action="pause">暂停</button>'
              : isCurrent
                ? '<button class="play-btn" data-action="play">播放</button>'
                : '<button class="play-btn" data-action="load">播放</button>') +
          '</div>';

        div.addEventListener('click', function(e) {
          if (e.target.tagName === 'BUTTON') return;
          loadMedia(item);
        });
        const btn = div.querySelector('button');
        if (btn) {
          btn.addEventListener('click', function(e) {
            e.stopPropagation();
            const action = btn.dataset.action;
            if (action === 'play') doPlay();
            else if (action === 'pause') doPause();
            else loadMedia(item);
          });
        }
        playlistBody.appendChild(div);
      });

      if (filtered.length === 0) {
        playlistBody.innerHTML = '<div class="playlist-empty">暂无视频</div>';
      }
    }

    function playNext() {
      if (!currentMedia) return;
      const idx = mediaList.findIndex(function(i) { return i.id === currentMedia.id; });
      let next = null;
      for (let i = idx + 1; i < mediaList.length; i++) {
        if (mediaList[i].isFinish != 1) { next = mediaList[i]; break; }
      }
      if (!next) {
        for (let i = 0; i < idx; i++) {
          if (mediaList[i].isFinish != 1) { next = mediaList[i]; break; }
        }
      }
      if (next) {
        showToast('即将播放: ' + next.name, 'success');
        setTimeout(function() { loadMedia(next); }, 1000);
      }
    }

    function doPlay() {
      isPlaying = true;
      startTick();
      safePlay();
      tickNum = 0;
      updatePlaylist();
    }

    function doPause() {
      isPlaying = false;
      stopTick();
      video.pause();
      updatePlaylist();
    }

    // ---- PiP ----
    async function enterPiP() {
      if (!document.pictureInPictureEnabled || isPiP) return;
      try {
        await video.requestPictureInPicture();
      } catch (e) {}
    }

    async function exitPiP() {
      if (document.pictureInPictureElement) {
        try { await document.exitPictureInPicture(); } catch (e) {}
      }
    }

    function togglePiP() {
      if (document.pictureInPictureElement) {
        exitPiP();
      } else {
        enterPiP();
      }
    }

    // ---- visibility change ----
    function onVisibilityChange() {
      if (document.hidden) {
        hiddenStartTime = Date.now();
        hiddenBasePosition = video.currentTime || 0;
      } else if (hiddenStartTime) {
        const elapsed = (Date.now() - hiddenStartTime) / 1000;
        const estimated = hiddenBasePosition + elapsed;
        hiddenStartTime = 0;
        if (estimated < (currentMedia ? currentMedia.duration : Infinity)) {
          setPosition(estimated);
        }
      }
    }

    // ---- events ----
    video.addEventListener('timeupdate', function() {
      curTimes = video.currentTime || 0;
      currentTimeEl.textContent = parseTime(curTimes);
    });

    video.addEventListener('loadedmetadata', function() {
      totalTimeEl.textContent = parseTime(video.duration || currentMedia?.duration || 0);
    });

    video.addEventListener('play', function() {
      isPlaying = true;
      report('play', 'start');
      updatePlaylist();
    });

    video.addEventListener('pause', function() {
      isPlaying = false;
      report('play', 'pause');
      updatePlaylist();
    });

    video.addEventListener('ended', function() {
      report('play', 'end');
      tick(true);
      setTimeout(playNext, 500);
    });

    video.addEventListener('error', function(e) {
      showToast('视频播放出错', 'error');
      report('play', 'error');
    });

    video.addEventListener('enterpictureinpicture', function() {
      isPiP = true;
      pipBtn.textContent = '退出画中画';
      pipBtn.classList.add('is-active');
    });

    video.addEventListener('leavepictureinpicture', function() {
      isPiP = false;
      pipBtn.textContent = '画中画';
      pipBtn.classList.remove('is-active');
    });

    volumeSlider.addEventListener('input', function() {
      setVolume(this.valueAsNumber);
    });

    muteBtn.addEventListener('click', function() {
      isMuted = !isMuted;
      setVolume(volume);
    });

    pipBtn.addEventListener('click', togglePiP);

    qualitySelect.addEventListener('change', function() {
      changeMedia(this.value);
    });

    panelToggle.addEventListener('click', function() {
      showPanel = !showPanel;
      playlistPanel.style.display = showPanel ? '' : 'none';
      panelToggle.textContent = showPanel ? '>' : '<';
    });

    hideFinishedCheck.addEventListener('change', updatePlaylist);

    // ---- init ----
    function init() {
      const params = new URLSearchParams(window.location.search);
      uid = params.get('uid') || localStorage.getItem('uid') || 0;
      token = params.get('token') || localStorage.getItem('token') || '';
      courseId = parseInt(params.get('courseId') || params.get('id') || '0');
      mediaId = parseInt(params.get('mediaId') || '0');

      if (params.get('uid')) localStorage.setItem('uid', uid);
      if (params.get('token')) localStorage.setItem('token', token);

      document.addEventListener('visibilitychange', onVisibilityChange);
      window.addEventListener('beforeunload', function() {
        stopTick();
        exitPiP();
      });

      if (courseId) {
        loadCourse();
      } else {
        videoTitle.textContent = '缺少课程ID';
      }
    }

    init();
  </script>
</body>
</html>