// ==UserScript==
// @name         CX 课程联播
// @namespace    cxq.queue
// @version      1.0.2
// @description  超星学习通：按队列依次自动学习多门课程。一门课的可自动任务点全部完成后，自动跳转下一门；答题类任务点会被跳过并记入报表。需与 OCS 网课助手配合使用。
// @author       cxq
// @match        *://*.chaoxing.com/*
// @grant        GM_getValue
// @grant        GM_setValue
// @grant        GM_notification
// @grant        GM_setClipboard
// @grant        unsafeWindow
// @run-at       document-idle
// ==/UserScript==

(function () {
  'use strict';

  // ============ 常量 ============

  var KEY = 'cxq.state.v1';
  var TICK_MS = 2000;
  var MIN_STAY_MS = 20 * 1000;       // 进入课程后至少待 20 秒才允许判定
  var QUIET_MS = 90 * 1000;          // 无变化静默阈值（兜底通道）
  var QUIZ_QUIET_MS = 25 * 1000;     // 已确认"只剩答题"时的缩短阈值
  var NAV_DELAY_MIN = 2000;          // 课程之间随机间隔下限
  var NAV_DELAY_MAX = 10000;         // 上限
  var NAV_MAX_TRIES = 3;             // 同一门课最多尝试进入几次
  var STALL_LIMIT = 90;              // 连续 90 次 tick 读不到目录 → 判失败
  var FRAME_IDLE_MAX = 60000;        // 内嵌页 1 分钟无心跳 → 视为空课程/卡死
  var FRAME_BEAT_MS = 10000;         // 子帧心跳间隔（必须明显小于上面的闲置阈值）
  var QUIZ_MODULES = ['work', 'exam'];

  // ============ 小工具 ============

  function $(s, r) { try { return (r || document).querySelector(s); } catch (e) { return null; } }
  function $$(s, r) { try { return Array.prototype.slice.call((r || document).querySelectorAll(s)); } catch (e) { return []; } }

  function eachDoc(cb, doc, depth) {
    doc = doc || document; depth = depth || 0;
    if (depth > 4) return;
    try { cb(doc, depth); } catch (e) { /* 单帧失败不影响整体 */ }
    $$('iframe', doc).forEach(function (f) {
      var d = null;
      try { d = f.contentDocument; } catch (e) { d = null; }
      if (d) eachDoc(cb, d, depth + 1);
    });
  }

  function hhmmss(ms) {
    if (!ms || ms < 0) return '0分';
    var s = Math.floor(ms / 1000);
    var h = Math.floor(s / 3600), m = Math.floor((s % 3600) / 60);
    return h ? (h + '小时' + m + '分') : (m + '分');
  }

  function clock() {
    var d = new Date();
    return [d.getHours(), d.getMinutes(), d.getSeconds()].map(function (n) {
      return String(n).padStart(2, '0');
    }).join(':');
  }

  function esc(s) {
    return String(s == null ? '' : s)
      .replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/"/g, '&quot;');
  }

  // ============ 存储 ============

  var hasGM = (typeof GM_getValue === 'function' && typeof GM_setValue === 'function');

  function blank() {
    return { v: 1, running: false, cursor: 0, queue: [], lastNav: null, navGuard: null, incDone: false, logs: [], updatedAt: 0 };
  }

  function readState() {
    var s = blank();
    try {
      var raw = hasGM ? GM_getValue(KEY, '') : localStorage.getItem(KEY);
      if (!raw) return s;
      var o = (typeof raw === 'string') ? JSON.parse(raw) : raw;
      if (o && typeof o === 'object') {
        s.running = !!o.running;
        s.cursor = Number(o.cursor) || 0;
        s.queue = Array.isArray(o.queue) ? o.queue : [];
        s.lastNav = o.lastNav || null;
        s.navGuard = o.navGuard || null;
        s.incDone = !!o.incDone;
        s.logs = Array.isArray(o.logs) ? o.logs : [];
        s.updatedAt = Number(o.updatedAt) || 0;
      }
    } catch (e) { /* 存储损坏则回退到空状态 */ }
    return s;
  }

  function writeState(s) {
    s.updatedAt = Date.now();
    try {
      var v = JSON.stringify(s);
      if (hasGM) GM_setValue(KEY, v);
      else localStorage.setItem(KEY, v);
    } catch (e) { /* 忽略写失败 */ }
  }

  var S = readState();

  function save() { writeState(S); }

  function log(msg) {
    S.logs.push(clock() + '  ' + msg);
    if (S.logs.length > 120) S.logs = S.logs.slice(-120);
    save();                       // 立刻落盘：跳转后内存里的日志会丢
    console.log('[cxq] ' + msg);
  }

  function notify(text) {
    try {
      if (typeof GM_notification === 'function') GM_notification({ title: 'CX 课程联播', text: text, timeout: 8000 });
    } catch (e) { /* 忽略 */ }
  }

  // ============ 页面探测 ============

  function urlCourseId() {
    try {
      var p = new URLSearchParams(location.search);
      return p.get('courseId') || p.get('courseid') || p.get('courseID') || null;
    } catch (e) { return null; }
  }

  function isStudyPage() {
    return /\/mycourse\/studentstudy/.test(location.pathname);
  }

  function readChapters() {
    return $$('[onclick^="getTeacherAjax"]').map(function (el, i) {
      var row = el.parentElement;
      var cnt = row ? $('input.jobUnfinishCount', row) : null;
      var m = (el.getAttribute('onclick') || '').match(/\('(.*?)','(.*?)','(.*?)'\)/);
      return {
        i: i,
        chapterId: m ? m[3] : null,
        unFinish: cnt ? (Number(cnt.value) || 0) : 0,
        hasCount: !!cnt,
        active: row ? row.classList.contains('posCatalog_active') : false,
        text: (el.textContent || '').replace(/\s+/g, ' ').trim()
      };
    });
  }

  function anyMediaPlaying() {
    var playing = false;
    eachDoc(function (doc) {
      $$('video,audio', doc).forEach(function (m) {
        if (!m.paused && !m.ended && m.duration > 0) playing = true;
      });
    });
    return playing;
  }

  // 当前章节的任务点类型（来自卡片 iframe 的 window.attachments）
  function currentJobModules(chapterId) {
    if (!chapterId) return null;
    var found = [];
    eachDoc(function (doc) {
      var a = null;
      try { a = doc.defaultView && doc.defaultView.attachments; } catch (e) { a = null; }
      if (Array.isArray(a) && a.length) found = found.concat(a);
    });
    if (!found.length) return null;
    var mine = found.filter(function (x) {
      return String((x && x.otherInfo) || '').indexOf('nodeId_' + chapterId) >= 0;
    });
    if (!mine.length) return null;
    return mine.map(function (x) {
      return (x.property && x.property.module) || x.type || '?';
    });
  }

  // 挡路弹窗：需要人工点「同意」才能进入的页面（诚信承诺书等）
  var BLOCKERS = [
    ['a.commitBtn.agreeStart', '需要先同意「诚信承诺书」'],
    ['.commitment-content-dialog', '需要先同意「诚信承诺书」'],
    ['.commitBtn.agreeStart', '需要先同意「诚信承诺书」'],
    ['.popDiv.course-pop', '有弹窗挡住页面']
  ];

  function isVisible(el) {
    if (!el) return false;
    var r = el.getBoundingClientRect();
    if (r.width <= 0 || r.height <= 0) return false;
    try {
      var st = el.ownerDocument.defaultView.getComputedStyle(el);
      if (st.display === 'none' || st.visibility === 'hidden' || st.opacity === '0') return false;
    } catch (e) { /* 忽略 */ }
    return true;
  }

  function detectBlocker() {
    for (var i = 0; i < BLOCKERS.length; i++) {
      var els = $$(BLOCKERS[i][0]);
      for (var j = 0; j < els.length; j++) {
        if (isVisible(els[j])) return BLOCKERS[i][1];
      }
    }
    return '';
  }

  function probe() {
    var chapters = readChapters();
    if (!chapters.length) return { state: 'empty' };

    var tabs = $$('.prev_ul li');
    var inFinalTab = tabs.length === 0 ? true : tabs[tabs.length - 1].classList.contains('active');
    var activeIdx = chapters.findIndex(function (c) { return c.active; });
    if (activeIdx < 0) return { state: 'noactive', chapters: chapters };

    var cur = chapters[activeIdx];
    var after = chapters.slice(activeIdx + 1).filter(function (c) { return c.hasCount && c.unFinish > 0; });
    var total = chapters.reduce(function (a, c) { return a + (c.hasCount ? c.unFinish : 0); }, 0);
    var playing = anyMediaPlaying();
    var mods = currentJobModules(cur.chapterId);
    var quizOnly = !!(mods && mods.length && mods.every(function (m) { return QUIZ_MODULES.indexOf(m) >= 0; }));

    return {
      state: 'ok',
      chapters: chapters,
      total: total,
      activeIdx: activeIdx,
      activeText: cur.text,
      activeId: cur.chapterId,
      inFinalTab: inFinalTab,
      afterCount: after.length,
      playing: playing,
      modules: mods,
      quizOnly: quizOnly,
      structOk: inFinalTab && after.length === 0
    };
  }

  // ============ 调度 ============

  var startedAt = Date.now();
  var lastChangeAt = Date.now();
  var lastSig = '';
  var stall = 0;
  var navPending = false;   // 已经安排了一次跳转，跳走之前不再做任何调度决策
  var navTimer = null;      // 延迟跳转定时器，暂停/清空/手动跳课时必须取消
  var navToken = 0;         // 防止已进入事件队列的旧回调在取消后仍执行
  var nameTries = 0;        // 本页已尝试补正课名的次数（最多 12 次 ≈ 24 秒）
  var blockerTicks = 0;     // 挡路弹窗连续出现次数
  var entryTries = 0;       // 入口解析尝试次数
  var navTry = 0;           // 已尝试点击左侧「章节」的次数
  var entryClickIdx = 0;    // 下一个尝试点击的章节条目序号
  var lastAutoIdx = -1;     // 上次自动选中的小节序号（避免连点同一个）
  var lastEntryClickAt = 0; // 上次点击章节条目的时间
  var frameWait = false;    // 是否已转入"等待内嵌页回报"模式
  var frameWaitAt = 0;      // 进入该模式的时间
  var lastFrameLogAt = 0;   // 已消费的子帧日志时间戳

  function findCourseIndexByUrl() {
    var cid = urlCourseId();
    if (!cid) return -1;
    for (var i = 0; i < S.queue.length; i++) {
      if (String(S.queue[i].courseId) === String(cid)) return i;
    }
    return -1;
  }

  function normUrl(u) {
    try { var x = new URL(u); x.hash = ''; return x.href; } catch (e) { return String(u); }
  }

  function onTargetPage(courseId) {
    return isStudyPage() && String(urlCourseId()) === String(courseId);
  }

  // 是不是"这门课"的任意页面（课程主页 / 学习页都算）
  function onCoursePage(courseId) {
    return !!courseId && String(urlCourseId()) === String(courseId);
  }

  function findVisible(sel, textRe) {
    var els = $$(sel);
    for (var i = 0; i < els.length; i++) {
      if (textRe && !textRe.test(String(els[i].textContent || '').replace(/\s+/g, ''))) continue;
      if (isVisible(els[i])) return els[i];
    }
    return null;
  }

  // 跨同源 iframe 找第一个可见元素
  function pick(sel, textRe) {
    var hit = null;
    eachDoc(function (doc) {
      if (hit) return;
      var els = $$(sel, doc);
      for (var i = 0; i < els.length; i++) {
        if (textRe && !textRe.test(String(els[i].textContent || '').replace(/\s+/g, ''))) continue;
        if (isVisible(els[i])) { hit = els[i]; return; }
      }
    });
    return hit;
  }

  function pageWin() {
    try { return (typeof unsafeWindow !== 'undefined' && unsafeWindow) || window; } catch (e) { return window; }
  }

  // 跨同源 iframe 收集所有可见元素
  function pickAll(sel) {
    var out = [];
    eachDoc(function (doc) {
      var els = $$(sel, doc);
      for (var i = 0; i < els.length; i++) {
        if (isVisible(els[i])) out.push(els[i]);
      }
    });
    return out;
  }

  // 章节条目里，"1.1" 这种带小数点的是具体小节（点了进学习页）；
  // 只有 "1" 的多半是章目录，点了只会展开/收起。返回应点击的下标，找不到返回 -1
  function pickChapterIndex(items) {
    for (var i = 0; i < items.length; i++) {
      var bar = items[i].querySelector('.catalog_sbar, .catalog_sbar2, em, i, .num');
      if (bar) {
        var t = String(bar.textContent || '').replace(/\s+/g, '');
        if (/^\d+(\.\d+)+$/.test(t)) return i;
        continue;
      }
      var txt = String(items[i].textContent || '').replace(/\s+/g, ' ').trim();
      if (/^\d+(\.\d+)+\s/.test(txt)) return i;
    }
    return -1;
  }
  function clickByText(txt) {
    var best = null, bestScore = 1e9;
    eachDoc(function (doc) {
      var els = doc.querySelectorAll('a, span, li, div, dt, dd, em, i, b');
      for (var i = 0; i < els.length; i++) {
        var el = els[i];
        if (!isVisible(el)) continue;
        var t = String(el.textContent || '').replace(/\s+/g, '');
        if (t !== txt && t !== txt + 'NEW') continue;
        var score = el.querySelectorAll('*').length;
        if (score < bestScore) { bestScore = score; best = el; }
      }
    });
    return best;
  }

  // 从课程主页进入学习页：直达链接 → 页面自身的 getTeacherAjax → 目录节点 → 点左侧【章节】
  function resolveEntry(cur) {
    entryTries++;
    if (!frameWait && entryTries > 25) {
      cur.status = 'failed';
      cur.reason = '找不到章节入口（可能是空课程）';
      save();
      log('跳过课程：' + cur.name + '（没找到任何章节入口，可能是空课程）');
      notify(cur.name + '：找不到章节入口，已跳过');
      goNext();
      return;
    }

    // 1) 页面上已经有直达学习页的链接
    var direct = pick('a[href*="studentstudy"]') || pick('a[href*="knowledge/cards"]');
    if (direct) {
      log('进入学习页：' + (direct.textContent || '').replace(/\s+/g, ' ').trim().slice(0, 20));
      location.href = direct.href;
      return;
    }

    // 2) onclick 里藏着 learning 地址
    var ocEl = pick('[onclick*="studentstudy"]');
    if (ocEl) {
      var m = String(ocEl.getAttribute('onclick') || '').match(/['"]([^'"]*studentstudy[^'"]*)['"]/);
      if (m) { log('从 onclick 取到学习页地址'); location.href = m[1]; return; }
    }

    // 3) 章节目录节点：优先直接调页面自己的 getTeacherAjax（不新开标签页）
    var node = pick('[onclick*="getTeacherAjax"]');
    if (node) {
      var args = String(node.getAttribute('onclick') || '').match(/getTeacherAjax\(([^)]*)\)/);
      var fn = pageWin().getTeacherAjax;
      if (args && typeof fn === 'function') {
        var parts = args[1].split(',').map(function (s) {
          return s.trim().replace(/^['"]|['"]$/g, '');
        });
        if (parts.length >= 3) {
          log('调用 getTeacherAjax 进入章节：' + parts[2]);
          fn(parts[0], parts[1], parts[2]);
          return;
        }
      }
      log('点击章节目录节点');
      node.click();
      return;
    }

    // 4) 超星课程主页的章节条目：<a class="clicktitle">1.1 直流稳压电源</a>（无 href / onclick，纯 JS 绑定）
    var items = pickAll('a.clicktitle') || [];
    if (items.length) {
      if (Date.now() - lastEntryClickAt < 5000) { render(false, null); return; }
      var auto = pickChapterIndex(items);
      if (auto >= 0 && auto === lastAutoIdx) auto = -1;   // 同一节点连点无效，改走递进
      var idx = auto >= 0 ? auto : Math.min(entryClickIdx, items.length - 1);
      if (auto >= 0) lastAutoIdx = auto;
      entryClickIdx++;
      lastEntryClickAt = Date.now();
      var label = String(items[idx].textContent || '').replace(/\s+/g, ' ').trim().slice(0, 20);
      log('点击章节条目：' + label + '（第 ' + (idx + 1) + ' 个' + (auto >= 0 ? '·小节' : '·递进') + '）');
      items[idx].click();
      return;
    }

    // 5) 目录容器
    var cat = pick('.posCatalog_select a') || pick('.posCatalog_select');
    if (cat) { log('点击目录项'); cat.click(); return; }

    // 6) 左侧【章节】导航：事件常绑在 span.nav_content 这类最内层元素上，点外层 <a> 无效
    if (navTry < 2 && (navTry === 0 || Date.now() - lastEntryClickAt > 6000)) {
      var nav = navTry === 0 ? clickByText('章节') : pick('a', /章节/);
      if (nav) {
        navTry++;
        lastEntryClickAt = Date.now();
        var ncls = String(nav.className || '').trim();
        log('点击左侧「章节」（第 ' + navTry + ' 次 · ' + nav.tagName.toLowerCase() + (ncls ? '.' + ncls.split(/\s+/).join('.') : '') + '）');
        nav.click();
        return;
      }
    }

    // 章节在跨域 iframe 里：点完「章节」后顶层文档不会变，继续点也没有意义
    if (!frameWait && navTry >= 2 && $$('iframe').length) {
      frameWait = true;
      frameWaitAt = Date.now();
      log('章节在内嵌框里，顶层点不到，改为等待子页面回报');
    }
    if (frameWait && Date.now() - Math.max(frameWaitAt, lastFrameLogAt) > FRAME_IDLE_MAX) {
      cur.status = 'failed';
      cur.reason = '页面没有可进入的章节';
      save();
      log('跳过课程：' + cur.name + '（内嵌页 1 分钟无心跳，可能是空课程或页面卡住）');
      notify(cur.name + '：没有可进入的章节，已跳过');
      goNext();
      return;
    }

    render(false, null);
  }

  function clearNavGuard() {
    if (S.navGuard) { S.navGuard = null; save(); }
  }

  // 取消尚未执行的课程跳转。递增 token，确保旧定时器回调失效。
  function cancelPendingNavigation() {
    navToken++;
    if (navTimer !== null) {
      clearTimeout(navTimer);
      navTimer = null;
    }
    navPending = false;
  }

  function resetCourseRuntime() {
    startedAt = Date.now();
    lastChangeAt = Date.now();
    lastSig = '';
    stall = 0;
    blockerTicks = 0;
    entryTries = 0;
    navTry = 0;
    entryClickIdx = 0;
    lastAutoIdx = -1;
    lastEntryClickAt = 0;
    frameWait = false;
    frameWaitAt = 0;
    lastFrameLogAt = 0;
  }

  function navigate(url, reason) {
    if (navPending) return;                 // 已经安排跳转了，避免 tick 重复触发
    if (normUrl(url) === normUrl(location.href)) return;  // 已经在目标页，交给接管逻辑

    var g = S.navGuard;
    if (!g || g.url !== url) g = { url: url, n: 0 };
    g.n += 1;
    S.navGuard = g;

    if (g.n > NAV_MAX_TRIES) {
      S.running = false;
      S.navGuard = null;
      log('「' + reason + '」连续 ' + g.n + ' 次跳转都没能进入，已停机。该课程链接可能已失效，请重新收录');
      save();
      notify('多次跳转未成功，联播已暂停');
      render(true);
      return;
    }

    navPending = true;
    clearSignal();
    clearFrameLog();
    // 课程之间随机等待，避免出现"固定 2 秒一跳"的机械节奏
    var wait = NAV_DELAY_MIN + Math.floor(Math.random() * (NAV_DELAY_MAX - NAV_DELAY_MIN + 1));
    var thisToken = ++navToken;
    log('跳转：' + reason + '（第 ' + g.n + ' 次，' + (wait / 1000).toFixed(1) + ' 秒后）');
    save();
    render(true);
    navTimer = setTimeout(function () {
      navTimer = null;
      // 定时器到期时再次确认队列仍在运行，且该回调没有被更新/取消。
      if (thisToken !== navToken || !navPending || !S.running) return;
      navPending = false;
      location.replace(url);
    }, wait);
  }

  function startCourse(idx, opts) {
    var c = S.queue[idx];
    if (!c) { finishQueue(); return; }
    S.cursor = idx;
    c.status = 'running';
    clearSignal();
    clearFrameLog();
    c.startedAt = c.startedAt || Date.now();
    c.reason = '';
    save();
    log('开始课程：' + c.name);

    if (onTargetPage(c.courseId)) {
      clearNavGuard();
      resetCourseRuntime();
      render(true);
    } else if (onCoursePage(c.courseId)) {
      resetCourseRuntime();
      render(true);
    } else {
      navigate(c.url, c.name);
    }
  }

  function completeCourse(reason) {
    var c = S.queue[S.cursor];
    if (!c) return;
    c.status = 'done';
    c.finishedAt = Date.now();
    c.reason = reason || '完成';
    c.leftover = (typeof c._total === 'number') ? c._total : null;
    delete c._total;
    save();
    log('课程收工：' + c.name + '（' + c.reason + (c.leftover ? '，剩余 ' + c.leftover + ' 个答题任务点' : '') + '）');
    goNext();
  }

  function goNext() {
    var i = S.cursor + 1;
    while (i < S.queue.length && S.queue[i].status === 'done') i++;
    if (i >= S.queue.length) { finishQueue(); return; }
    startCourse(i);
  }

  function finishQueue() {
    S.running = false;
    cancelPendingNavigation();
    S.navGuard = null;
    save();
    var done = S.queue.filter(function (c) { return c.status === 'done'; }).length;
    var msg = '联播结束：' + done + ' / ' + S.queue.length + ' 门课完成';
    log(msg);
    render(true);
    notify(msg);
  }

  function tick() {
    if (navPending) return;

    var p = null;
    try { p = isStudyPage() ? probe() : null; } catch (e) { p = null; }

    // 进到某门课就补一次课名；页面可能还没渲染完，因此在 24 秒内最多重试 12 次
    if (nameTries < 12 && isStudyPage()) {
      var ci = findCourseIndexByUrl();
      if (ci >= 0 && isAutoName(S.queue[ci])) {
        nameTries++;
        if (refreshNameIfNeeded(S.queue[ci])) nameTries = 99;
      } else {
        nameTries = 99;
      }
    }

    if (!S.running) { render(false, p); return; }

    var cur = S.queue[S.cursor];
    if (!cur) { finishQueue(); return; }

    // 子帧的动作通过独立通道回报，显示在面板日志里
    var fl = readFrameLog();
    if (fl && fl.at > lastFrameLogAt) {
      lastFrameLogAt = fl.at;                       // 心跳只续命，不写进日志
      if (fl.kind !== 'beat') log('[帧] ' + fl.msg);
    }

    // iframe 内的学习页学完了会写信号过来，由顶层负责切课
    var sg = readSignal();
    if (sg && String(sg.courseId) === String(cur.courseId) && sg.at > startedAt) {
      clearSignal();
      completeCourse('内嵌学习页判定完成');
      return;
    }

    var hereCid = String(urlCourseId() || '');
    if (hereCid !== String(cur.courseId)) {
      navigate(cur.url, '进入课程');
      return;
    }
    if (!isStudyPage()) {
      // 已经在这门课的页面上，但还没到学习页 → 解析入口
      resolveEntry(cur);
      return;
    }
    clearNavGuard();

    // 被弹窗挡住的课既读不到目录也学不了：连续 3 次（约 6 秒）确认后跳过，不拖住整条队列
    var block = detectBlocker();
    if (block) {
      blockerTicks++;
      if (blockerTicks >= 3) {
        blockerTicks = 0;
        cur.status = 'failed';
        cur.reason = block;
        save();
        log('跳过课程：' + cur.name + '（' + block + '）');
        notify(cur.name + '：' + block + '，已跳过');
        goNext();
        return;
      }
      render(false, p);
      return;
    }
    blockerTicks = 0;

    if (!p || p.state === 'empty') {
      stall++;
      if (stall >= STALL_LIMIT) {
        cur.status = 'failed';
        cur.reason = '3 分钟内读不到章节目录';
        save();
        log('课程失败：' + cur.name + '，读不到章节目录');
        goNext();
      } else {
        render(false, p);
      }
      return;
    }
    if (p.state !== 'ok') { render(false, p); return; }
    stall = 0;

    cur._total = p.total;

    var sig = [p.total, p.activeIdx, p.inFinalTab, p.afterCount, p.playing, p.quizOnly].join('|');
    if (sig !== lastSig) {
      lastSig = sig;
      lastChangeAt = Date.now();
    }

    var quiet = Date.now() - lastChangeAt;
    var stayed = Date.now() - startedAt;
    var quietNeed = p.quizOnly ? QUIZ_QUIET_MS : QUIET_MS;

    // 当前章节只剩答题时，章节里不可能还有视频任务点，此时任何播放都不该阻塞判定
    var noMediaBlock = p.quizOnly || !p.playing;
    var done = p.structOk && noMediaBlock && stayed > MIN_STAY_MS && quiet > quietNeed;

    render(false, p);

    if (done) {
      completeCourse('后面无未完成任务点' + (p.quizOnly ? '，当前章节仅剩答题' : ''));
    }
  }

  // ============ 跨 frame 协作 ============
  // 课程主页的章节常放在跨域 iframe 里，顶层点不到；让脚本在 iframe 内也跑一份，
  // 由子页面判断"学完了"，写一个信号，顶层读到后切下一门。

  var SIGNAL_KEY = 'cxq.signal.v1';
  var FLOG_KEY = 'cxq.framelog.v1';

  // 子帧不能直接改主状态（会和顶层抢写），单独写一个"最近动作"让顶层去取
  // kind: 'act' 有意义的动作（会显示到面板日志）；'beat' 纯心跳（只用来续命，不显示）
  function writeFrameLog(msg, kind) {
    try {
      var v = JSON.stringify({ msg: String(msg).slice(0, 140), kind: kind || 'act', at: Date.now() });
      if (hasGM) GM_setValue(FLOG_KEY, v);
      else localStorage.setItem(FLOG_KEY, v);
    } catch (e) { /* 忽略 */ }
  }

  function readFrameLog() {
    try {
      var raw = hasGM ? GM_getValue(FLOG_KEY, '') : localStorage.getItem(FLOG_KEY);
      return raw ? JSON.parse(raw) : null;
    } catch (e) { return null; }
  }

  function clearFrameLog() {
    try {
      if (hasGM) GM_setValue(FLOG_KEY, '');
      else localStorage.removeItem(FLOG_KEY);
    } catch (e) { /* 忽略 */ }
  }

  function writeSignal(courseId, kind) {
    try {
      var v = JSON.stringify({ courseId: String(courseId), kind: kind, at: Date.now() });
      if (hasGM) GM_setValue(SIGNAL_KEY, v);
      else localStorage.setItem(SIGNAL_KEY, v);
    } catch (e) { /* 忽略 */ }
  }

  function readSignal() {
    try {
      var raw = hasGM ? GM_getValue(SIGNAL_KEY, '') : localStorage.getItem(SIGNAL_KEY);
      return raw ? JSON.parse(raw) : null;
    } catch (e) { return null; }
  }

  function clearSignal() {
    try {
      if (hasGM) GM_setValue(SIGNAL_KEY, '');
      else localStorage.removeItem(SIGNAL_KEY);
    } catch (e) { /* 忽略 */ }
  }

  function startFrameWatcher() {
    var fStarted = Date.now();
    var fSig = '', fChange = Date.now(), sent = false;
    var clickIdx = 0, lastClick = 0, lastAutoIdx = -1, lastBeat = 0;
    // 目录点击后如果 DOM 没变化，最多对同一份目录尝试两次，避免每 6 秒重复点击
    var lastItemsSig = '', sameSigAttempts = 0, gaveUpLogged = false;

    console.log('[cxq] 子页面接管：' + location.href.slice(0, 80));

    setInterval(function () {
      try {
        if (sent) return;
        var st = readState();
        if (!st.running) return;
        var cur = st.queue[st.cursor];
        if (!cur) return;

        // 阶段一：这个 frame 里就是章节目录 → 由它自己点进章节（顶层点不到跨域 iframe 内部）
        if (!isStudyPage()) {
          if (!document.querySelector('a.clicktitle')) return;
          var items = pickAll('a.clicktitle');
          if (!items.length) return;
          if (Date.now() - lastClick < 6000) return;

          // 用目录条目文本构造稳定签名；内容没变就别反复点
          var itemsSig = items.map(function (el) {
            return String(el.textContent || '').replace(/\s+/g, ' ').trim();
          }).join('||');
          if (itemsSig !== lastItemsSig) {
            lastItemsSig = itemsSig;
            sameSigAttempts = 0;
            gaveUpLogged = false;
          }
          if (sameSigAttempts >= 2) {
            if (!gaveUpLogged) {
              gaveUpLogged = true;
              writeFrameLog('目录点了 2 次没变化，停止点击（可能不是可跳转的章节条目）');
            }
            return;
          }

          var auto = pickChapterIndex(items);
          if (auto >= 0 && auto === lastAutoIdx) auto = -1;
          var idx = auto >= 0 ? auto : Math.min(clickIdx, items.length - 1);
          if (auto >= 0) lastAutoIdx = auto;
          clickIdx++;
          sameSigAttempts++;
          lastClick = Date.now();

          var label = String(items[idx].textContent || '').replace(/\s+/g, ' ').trim().slice(0, 20);
          writeFrameLog('子页面点击章节：' + label + '（第 ' + (idx + 1) + ' 个' + (auto >= 0 ? '·小节' : '·递进') + '）');
          items[idx].click();
          return;
        }

        // 阶段二：已经是学习页 → 判定是否学完
        var p = probe();

        // 心跳：不论目录是否可读都要发。否则"切章节/加载中"那几秒会被顶层误判成空课程
        if (Date.now() - lastBeat > FRAME_BEAT_MS) {
          lastBeat = Date.now();
          writeFrameLog('存活·' + (p.state === 'ok' ? ('剩余 ' + p.total + ' 个任务点') : '目录加载中'), 'beat');
        }

        if (p.state !== 'ok') return;
        var sig = [p.total, p.activeIdx, p.inFinalTab, p.afterCount, p.playing, p.quizOnly].join('|');
        if (sig !== fSig) { fSig = sig; fChange = Date.now(); }

        var quiet = Date.now() - fChange;
        var need = p.quizOnly ? 25000 : 90000;
        if (p.structOk && (p.quizOnly || !p.playing) && (Date.now() - fStarted) > 20000 && quiet > need) {
          sent = true;
          writeSignal(cur.courseId, 'done');
          writeFrameLog('子页面判定完成：' + cur.name);
        }
      } catch (e) { /* 忽略 */ }
    }, 2000);
  }

  // ============ 面板 ============

  // 非顶层 frame：只做"学完回报"，不建面板、不调度
  var IS_TOP = (function () {
    try { return window.top === window.self; } catch (e) { return false; }
  })();

  if (!IS_TOP) {
    try { startFrameWatcher(); } catch (e) { console.error('[cxq] frame watcher', e); }
    return;
  }

  var host = document.createElement('div');
  host.id = 'cxq-host';
  host.style.cssText = 'all:initial;position:fixed;right:18px;bottom:18px;z-index:2147483646;';
  var root = host.attachShadow({ mode: 'open' });

  root.innerHTML = [
    '<style>',
    ':host{all:initial;color-scheme:light}',
    '*{box-sizing:border-box;font-family:"Microsoft YaHei",system-ui,sans-serif}',
    '.panel{width:390px;max-height:76vh;display:flex;flex-direction:column;background:#fff;border:1px solid #e6eaf0;border-radius:16px;box-shadow:0 12px 38px rgba(20,35,55,.18);overflow:hidden;color:#202938;font-size:13px}',
    '.hd{display:flex;align-items:center;gap:10px;padding:13px 15px;border-bottom:1px solid #edf0f4;background:linear-gradient(135deg,#fbfcfe,#f5f8fc)}',
    '.brandmark{width:30px;height:30px;display:grid;place-items:center;border-radius:10px;background:#e8f1ff;color:#245da8;font-size:15px;font-weight:800;flex:none}',
    '.brand{min-width:0;display:flex;flex-direction:column;gap:2px}',
    '.brand b{font-size:14px;line-height:1.2;font-weight:700;letter-spacing:.1px}',
    '.brand small{font-size:10px;color:#8993a2}',
    '.hd-right{margin-left:auto;display:flex;align-items:center;gap:8px}',
    '.dot{width:8px;height:8px;border-radius:50%;background:#aab3c0;flex:none}',
    '.dot.on{background:#20a36b;box-shadow:0 0 0 3px rgba(32,163,107,.12)}',
    '.badge{padding:4px 9px;border-radius:20px;font-size:11px;background:#eef1f5;color:#667184;white-space:nowrap}',
    '.badge.on{background:#e8f7ef;color:#168253}',
    '.iconbtn{width:27px;height:27px;border:0;border-radius:8px;background:transparent;color:#7d8796;cursor:pointer;font-size:17px;line-height:1}',
    '.iconbtn:hover{background:#e9eef5;color:#26364b}',
    '.body{overflow:auto;padding:12px 14px 13px;min-height:120px}',
    '.panel.min .body,.panel.min .ft{display:none}',
    '.tabs{display:flex;gap:5px;padding:3px;background:#f1f4f8;border-radius:10px;margin-bottom:13px}',
    '.tab{flex:1;border:0;border-radius:8px;padding:7px 8px;background:transparent;color:#788395;font-size:12px;cursor:pointer}',
    '.tab.active{background:#fff;color:#245da8;box-shadow:0 1px 4px rgba(25,45,70,.10);font-weight:700}',
    '.section-head{display:flex;align-items:center;justify-content:space-between;margin:13px 0 8px}',
    '.section-head:first-child{margin-top:0}',
    '.section-title{font-size:12px;font-weight:700;color:#39475a}',
    '.section-sub{font-size:10px;color:#929baa}',
    '.stats{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:7px;margin-bottom:12px}',
    '.stat{padding:9px 10px;border:1px solid #edf0f4;border-radius:11px;background:#fbfcfe;min-width:0}',
    '.stat strong{display:block;font-size:18px;line-height:1.15;color:#26364b;font-weight:750;font-variant-numeric:tabular-nums}',
    '.stat span{display:block;margin-top:4px;font-size:10px;color:#8993a2}',
    '.stat.good strong{color:#168253}.stat.warn strong{color:#c17a25}.stat.bad strong{color:#c34b4b}',
    '.progress-card{padding:12px;border:1px solid #e8edf4;border-radius:12px;background:#f9fbfe;margin-bottom:12px}',
    '.progress-top{display:flex;align-items:center;justify-content:space-between;gap:8px;margin-bottom:9px}',
    '.progress-name{font-size:12px;font-weight:700;color:#334258;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}',
    '.progress-value{font-size:11px;color:#60728a;font-variant-numeric:tabular-nums;white-space:nowrap}',
    '.track{height:6px;background:#e7edf5;border-radius:99px;overflow:hidden}',
    '.track>i{display:block;height:100%;border-radius:99px;background:linear-gradient(90deg,#4d8de0,#2b70c5);transition:width .2s ease}',
    '.current{padding:12px;border:1px solid #dce8f8;border-radius:12px;background:linear-gradient(135deg,#f7faff,#f2f7ff);margin-bottom:13px}',
    '.current-label{display:flex;align-items:center;gap:6px;color:#4b6f9e;font-size:10px;font-weight:700;letter-spacing:.3px;margin-bottom:6px}',
    '.current-title{font-size:13px;font-weight:700;color:#253b59;line-height:1.45;overflow-wrap:anywhere}',
    '.current-detail{margin-top:7px;font-size:11px;color:#718198;line-height:1.55}',
    '.current-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:7px 12px;margin-top:10px;padding-top:9px;border-top:1px solid #e4edf8}',
    '.metric{min-width:0}.metric span{display:block;color:#8a96a7;font-size:10px;margin-bottom:2px}.metric b{font-size:11px;color:#45566d;font-weight:600;overflow-wrap:anywhere}',
    '.queue-list{display:flex;flex-direction:column;gap:7px}',
    '.course{display:grid;grid-template-columns:25px minmax(0,1fr) auto;gap:8px;align-items:center;padding:9px 9px;border:1px solid #edf0f4;border-radius:11px;background:#fff;transition:border-color .15s,background .15s}',
    '.course.cur{border-color:#a9c8f0;background:#f7faff}',
    '.course-index{width:24px;height:24px;display:grid;place-items:center;border-radius:8px;background:#f0f3f7;color:#7b8798;font-size:10px;font-weight:700;font-variant-numeric:tabular-nums}',
    '.course.cur .course-index{background:#e2edfc;color:#2865ae}',
    '.course-main{min-width:0}',
    '.course-name{display:block;max-width:100%;padding:0;border:0;background:transparent;text-align:left;color:#344257;font-size:12px;font-weight:600;line-height:1.4;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;cursor:pointer}',
    '.course-name:hover{color:#2467b4}',
    '.course-meta{display:flex;align-items:center;gap:6px;margin-top:4px;min-width:0}',
    '.status{font-size:10px;color:#7d8999}',
    '.status.done{color:#168253}.status.failed{color:#c34b4b}.status.running{color:#286bc0}.status.pending{color:#8993a2}',
    '.course-actions{display:flex;align-items:center;gap:2px}',
    '.action{min-width:23px;height:24px;padding:0 5px;border:0;border-radius:6px;background:transparent;color:#8b95a3;font-size:11px;cursor:pointer}',
    '.action:hover{background:#edf2f8;color:#315d91}',
    '.action.danger:hover{background:#fff0f0;color:#c34b4b}',
    '.empty{padding:22px 10px;text-align:center;color:#98a2b0;font-size:12px;line-height:1.6;border:1px dashed #e3e8ef;border-radius:11px;background:#fbfcfe}',
    '.tool-card{padding:12px;border:1px solid #edf0f4;border-radius:11px;background:#fff;margin-bottom:9px}',
    '.tool-card-title{font-size:12px;font-weight:700;color:#39475a;margin-bottom:5px}',
    '.tool-card-desc{font-size:11px;color:#8a95a5;line-height:1.5;margin-bottom:9px}',
    '.tool-row{display:flex;gap:7px}',
    'button.tool{flex:1;min-width:0;padding:8px 9px;border:1px solid #dfe6ef;border-radius:8px;background:#fff;color:#4c5d73;font-size:11px;cursor:pointer}',
    'button.tool:hover{border-color:#9dbbe1;background:#f7faff;color:#245da8}',
    'button.tool.primary{border-color:#c8daf2;background:#eff6ff;color:#245da8}',
    '.chk{display:flex;align-items:center;gap:6px;margin-top:9px;font-size:11px;color:#718096;cursor:pointer}',
    '.result{white-space:pre-wrap;word-break:break-word;padding:9px;border-radius:8px;background:#f6f8fb;border:1px solid #edf0f4;color:#657287;font:10px/1.55 Consolas,monospace;max-height:150px;overflow:auto;margin-top:8px}',
    '.log-list{display:flex;flex-direction:column;gap:6px}',
    '.log-line{padding:7px 9px;border-left:2px solid #d9e4f2;background:#f8fafc;border-radius:0 7px 7px 0;color:#66758a;font:10px/1.5 Consolas,monospace;overflow-wrap:anywhere}',
    '.ft{display:flex;gap:7px;padding:10px 13px;border-top:1px solid #edf0f4;background:#fbfcfe}',
    'button.b{flex:1;min-width:0;padding:9px 6px;border:1px solid #dfe5ed;background:#fff;border-radius:9px;cursor:pointer;font-size:11px;color:#566477}',
    'button.b:hover{border-color:#a9c4e7;color:#245da8}',
    'button.b.primary{background:#286fc2;border-color:#286fc2;color:#fff;font-weight:700}',
    'button.b.primary:hover{background:#1e5fa9}',
    'button.b:disabled{opacity:.45;cursor:not-allowed}',
    '@media(max-width:440px){.panel{width:min(390px,calc(100vw - 20px))}}',
    '</style>',
    '<div class="panel">',
    '  <div class="hd">',
    '    <span class="brandmark">CX</span>',
    '    <div class="brand"><b>CX 课程联播</b><small>课程队列控制台</small></div>',
    '    <div class="hd-right"><span class="dot" id="dot"></span><span class="badge" id="badge">待机</span><button class="iconbtn" data-act="min" id="btn-min" title="收起面板">−</button></div>',
    '  </div>',
    '  <div class="body" id="body"></div>',
    '  <div class="ft">',
    '    <button class="b primary" data-act="toggle" id="btn-toggle">开始联播</button>',
    '    <button class="b" data-act="add" title="把当前学习页加入队列">收录当前</button>',
    '    <button class="b" data-act="report">生成报表</button>',
    '  </div>',
    '</div>'
  ].join('');

  document.body.appendChild(host);

  var elBody = root.getElementById('body');
  var elBadge = root.getElementById('badge');
  var elDot = root.getElementById('dot');
  var elToggle = root.getElementById('btn-toggle');
  var lastRender = '';
  var lastGrab = '';
  var lastScan = '';
  var uiTab = 'queue';

  function statusText(s) {
    return ({ pending: '待学', running: '进行中', done: '完成', failed: '失败' })[s] || s;
  }

  function render(force, p) {
    var doneCount = S.queue.filter(function (c) { return c.status === 'done'; }).length;
    var failedCount = S.queue.filter(function (c) { return c.status === 'failed'; }).length;
    var activeCount = S.queue.filter(function (c) { return c.status === 'pending' || c.status === 'running'; }).length;
    var progress = S.queue.length ? Math.round(doneCount / S.queue.length * 100) : 0;
    var cur = S.queue[S.cursor] || null;
    var sig = [
      S.running, S.cursor, S.queue.length, S.logs.length, uiTab,
      S.queue.map(function (c) { return c.status + (c.leftover || '') + c.name; }).join(','),
      p ? [p.total, p.activeIdx, p.structOk, p.playing, p.quizOnly].join('|') : 'x'
    ].join('#');

    if (!force && sig === lastRender) return;
    lastRender = sig;

    elToggle.textContent = S.running ? '暂停联播' : '开始联播';
    elDot.className = 'dot' + (S.running ? ' on' : '');
    elBadge.textContent = S.running ? (p && p.structOk ? '运行中' : '正在处理') : '待机';
    elBadge.className = 'badge' + (S.running ? ' on' : '');

    var h = [];
    h.push('<div class="tabs">' +
      '<button class="tab ' + (uiTab === 'queue' ? 'active' : '') + '" data-act="tab" data-tab="queue">课程队列</button>' +
      '<button class="tab ' + (uiTab === 'tools' ? 'active' : '') + '" data-act="tab" data-tab="tools">工具与日志</button>' +
      '</div>');

    if (uiTab === 'queue') {
      h.push('<div class="stats">' +
        '<div class="stat good"><strong>' + doneCount + '</strong><span>已完成</span></div>' +
        '<div class="stat"><strong>' + activeCount + '</strong><span>待处理</span></div>' +
        '<div class="stat ' + (failedCount ? 'bad' : '') + '"><strong>' + failedCount + '</strong><span>失败</span></div>' +
        '</div>');

      h.push('<div class="progress-card"><div class="progress-top"><span class="progress-name">队列整体进度</span><span class="progress-value">' + doneCount + ' / ' + S.queue.length + ' · ' + progress + '%</span></div>' +
        '<div class="track"><i style="width:' + progress + '%"></i></div></div>');

      if (cur) {
        var currentTitle = esc(cur.name || '未命名课程');
        var detail = S.running ? (p && p.state === 'ok' ? '正在处理课程章节与任务点' : (isStudyPage() ? '正在读取章节目录…' : '正在进入课程页面…')) : '队列尚未启动';
        h.push('<div class="current"><div class="current-label"><span>●</span> 当前课程</div>' +
          '<div class="current-title">' + currentTitle + '</div>' +
          '<div class="current-detail">' + detail + '</div>');
        if (p && p.state === 'ok') {
          h.push('<div class="current-grid">' +
            '<div class="metric"><span>当前章节</span><b>' + (p.activeIdx + 1) + ' / ' + p.chapters.length + '</b></div>' +
            '<div class="metric"><span>剩余任务点</span><b>' + p.total + '</b></div>' +
            '<div class="metric"><span>后续有活章节</span><b>' + p.afterCount + '</b></div>' +
            '<div class="metric"><span>媒体播放</span><b>' + (p.playing ? '检测到播放' : '未检测到播放') + '</b></div>' +
            '<div class="metric"><span>仅剩答题</span><b>' + (p.quizOnly ? '是' : (p.modules ? '否' : '未知')) + '</b></div>' +
            '<div class="metric"><span>结构判据</span><b>' + (p.structOk ? '成立' : '未成立') + '</b></div>' +
            '</div>');
        }
        h.push('</div>');
      } else {
        h.push('<div class="empty">队列还是空的。可以先扫描课程列表，或进入一门课程后点击「收录当前」。</div>');
      }

      h.push('<div class="section-head"><span class="section-title">课程列表</span><span class="section-sub">' + S.queue.length + ' 门课程</span>' +
        (S.queue.length ? '<button class="action danger" data-act="clearq" title="清空整个队列">清空队列</button>' : '') + '</div>');
      if (!S.queue.length) {
        h.push('<div class="empty">暂无课程</div>');
      } else {
        h.push('<div class="queue-list">');
        S.queue.forEach(function (c, i) {
          var cls = 'course' + (i === S.cursor && S.running ? ' cur' : '');
          var st = c.status || 'pending';
          h.push('<div class="' + cls + '">' +
            '<span class="course-index">' + (i + 1) + '</span>' +
            '<div class="course-main">' +
            '<button class="course-name" data-act="rename" data-i="' + i + '" title="点击修改课程名称">' + esc(c.name) + '</button>' +
            '<div class="course-meta"><span class="status ' + st + '">' + statusText(st) + '</span>' +
            (c.leftover ? '<span class="status">剩余答题 ' + c.leftover + '</span>' : '') +
            (c.reason ? '<span class="status" title="' + esc(c.reason) + '">· ' + esc(c.reason).slice(0, 18) + '</span>' : '') +
            '</div></div><div class="course-actions">' +
            (isAutoName(c) ? '<button class="action" data-act="grabname" data-i="' + i + '" title="抓取课程名称候选">名</button>' : '') +
            ((c.status === 'done' || c.status === 'failed')
              ? '<button class="action" data-act="restore" data-i="' + i + '" title="恢复为待学">↺</button>'
              : '<button class="action" data-act="skip" data-i="' + i + '" title="跳过这门课">跳</button>') +
            '<button class="action danger" data-act="del" data-i="' + i + '" title="从队列删除">×</button>' +
            '</div></div>');
        });
        h.push('</div>');
      }
    } else {
      if (!isStudyPage()) {
        h.push('<div class="tool-card"><div class="tool-card-title">课程发现</div>' +
          '<div class="tool-card-desc">在「我的课程」等课程列表页面扫描可识别的课程，并导入当前队列。</div>' +
          '<div class="tool-row"><button class="tool primary" data-act="scan">扫描本页全部课程</button></div>' +
          '<label class="chk"><input type="checkbox" data-act="incdone"' + (S.incDone ? ' checked' : '') + '> 包含「已完成」的课程</label>' +
          (lastScan ? '<div class="result">' + esc(lastScan) + '</div>' : '') + '</div>');
        h.push('<div class="tool-card"><div class="tool-card-title">页面诊断</div>' +
          '<div class="tool-card-desc">用于排查课程入口、章节目录及课程名称识别问题。抓取结果会自动复制到剪贴板。</div>' +
          '<div class="tool-row"><button class="tool" data-act="entdump">抓取章节入口元素</button></div></div>');
      } else {
        h.push('<div class="tool-card"><div class="tool-card-title">当前页面</div><div class="tool-card-desc">当前处于课程学习页面。可使用下方操作查看运行日志或生成报表。</div></div>');
      }
      if (lastGrab) {
        h.push('<div class="tool-card"><div class="tool-card-title">最近一次抓取结果</div>' +
          '<div class="tool-card-desc">结果已尝试复制到剪贴板；如复制失败，可从这里手动查看。</div>' +
          '<div class="result" style="max-height:190px">' + esc(lastGrab) + '</div></div>');
      }
      h.push('<div class="section-head"><span class="section-title">运行日志</span><span class="section-sub">最近 ' + Math.min(20, S.logs.length) + ' 条</span></div>');
      if (S.logs.length) {
        h.push('<div class="log-list">');
        S.logs.slice(-20).forEach(function (line) { h.push('<div class="log-line">' + esc(line) + '</div>'); });
        h.push('</div>');
      } else {
        h.push('<div class="empty">暂无运行日志</div>');
      }
    }

    var keep = elBody.scrollTop;
    elBody.innerHTML = h.join('');
    elBody.scrollTop = keep;
  }

  // ============ 事件 ============

  var NAME_SELECTORS = [
    'dd.textHidden',
    '.courseName', '.course-name', '.courseTitle', '.course-title',
    '#courseName', '#courseTitle', '.posCatalog_title', '.catalog_title',
    '.Mooc2Head .title', '.Mooc2Head h1', '.ml_title', '.course_title',
    '.courseInfo .name', 'h1'
  ];
  var NAME_BAD = /学生学习界面|学习通|超星|我的课程|课程学习|学习页面|章节学习|^首页$/;
  var ACTIVE_CLS = ['active', 'cur', 'current', 'selected', 'on', 'check'];
  // 某些选择器天然就是课名容器，允许 2 字短名（例如「测量」「制图」）
  var NAME_MINLEN = { 'dd.textHidden': 2, '.courseName': 2, '.course-name': 2, '#courseName': 2 };

  function okName(t, min) {
    if (!t) return false;
    min = min || 3;
    if (t.length < min || t.length > 50) return false;
    return !NAME_BAD.test(t);
  }

  // 课程名优先取 title 属性：超星用 .textHidden 做视觉截断，textContent 可能不完整
  function readName(el) {
    return String(el.getAttribute('title') || el.textContent || '').replace(/\s+/g, ' ').trim();
  }

  function pickActive(list) {
    for (var i = 0; i < list.length; i++) {
      var cls = String(list[i].className || '').toLowerCase().split(/\s+/);
      for (var j = 0; j < ACTIVE_CLS.length; j++) {
        if (cls.indexOf(ACTIVE_CLS[j]) >= 0) return list[i];
      }
    }
    return null;
  }

  function guessCourseName() {
    for (var i = 0; i < NAME_SELECTORS.length; i++) {
      var sel = NAME_SELECTORS[i];
      var min = NAME_MINLEN[sel] || 3;
      var els = $$(sel).filter(function (el) { return okName(readName(el), min); });
      if (!els.length) continue;
      if (els.length > 1) {
        var act = pickActive(els);
        if (act) return readName(act);
      }
      return readName(els[0]);
    }
    var dt = (document.title || '').replace(/\s*[-—_|]\s*.*$/, '').trim();
    if (okName(dt)) return dt;
    console.warn('[cxq] 没找到课程名候选，已用 courseId 代替，可在面板点名字改名');
    return '';
  }

  function isAutoName(c) {
    if (!c) return false;
    if (typeof c.nameAuto === 'boolean') return !c.nameAuto;
    var n = String(c.name || '').trim();
    if (!n) return true;
    if (NAME_BAD.test(n)) return true;          // 旧版用 document.title 写进来的"学生学习界面"等
    return /^课程 \d+$/.test(n);
  }

  // 名字是兜底生成（或旧版本写入）时，进到该课程页再尝试识别一次；成功返回 true
  function refreshNameIfNeeded(c) {
    if (!isAutoName(c)) return false;
    var g = guessCourseName();
    if (!g || g === c.name) return false;
    c.name = g;
    c.nameAuto = true;
    save();
    log('自动补正课程名：' + g);
    render(true);
    return true;
  }

  // 登录区（用户名/头像/导航）标记出来，避免把真实姓名当成课程名
  var GRAB_SKIP = /(^|\s)(loginAfter|headRight|headLeft|headBottom|footer|nav|topBar)(\s|$)/;

  function insideSkipped(el) {
    var p = el;
    for (var i = 0; i < 6 && p; i++) {
      if (GRAB_SKIP.test(String(p.className || ''))) return true;
      p = p.parentElement;
    }
    return false;
  }

  // 全页转储"短文本叶子节点"，按纵向位置排序；隐藏元素、有 title 的、在登录区的都会标记
  // 用途：当自动识别失败时，人工找出课程名到底挂在哪个元素上
  function collectNameCandidates() {
    var out = [], seen = {};
    var all = document.querySelectorAll('body *');

    for (var i = 0; i < all.length; i++) {
      var el = all[i];
      if (el.children.length) continue;

      var raw = String(el.getAttribute('title') || el.textContent || '').replace(/\s+/g, ' ').trim();
      if (!raw || raw.length < 2 || raw.length > 40) continue;

      var ec = String(el.className || '').trim();
      var key = raw + '@' + el.tagName + '.' + ec;
      if (seen[key]) continue;
      seen[key] = 1;

      var r = el.getBoundingClientRect();
      var hidden = (r.width <= 0 || r.height <= 0) ? ' [隐藏]' : '';
      var hasTitle = el.getAttribute('title') ? ' [有title]' : '';
      var inHead = insideSkipped(el) ? ' [登录区]' : '';

      var chain = [], p = el.parentElement, n = 0;
      while (p && n < 3) {
        var pc = String(p.className || '').trim();
        chain.push(p.tagName.toLowerCase() + (pc ? '.' + pc.split(/\s+/).join('.') : ''));
        p = p.parentElement; n++;
      }

      out.push({
        top: Math.round(r.top),
        line: 'y=' + Math.round(r.top) + '\t' +
          el.tagName.toLowerCase() +
          (ec ? '.' + ec.split(/\s+/).join('.') : '') +
          (el.id ? '#' + el.id : '') +
          hidden + hasTitle + inHead +
          '  ::  "' + raw + '"  <-  ' + chain.join(' < ')
      });
    }

    out.sort(function (a, b) { return a.top - b.top; });
    return out.slice(0, 60).map(function (x) { return x.line; });
  }

  // ---------- 课程列表扫描 ----------

  function parseParams(str) {
    var out = {};
    var re = /(?:^|[?&;'"\s\\])(courseid|clazzid|cpi|enc|openc)=([^&'"\s>]+)/gi;
    var m;
    while ((m = re.exec(str))) {
      var k = m[1].toLowerCase();
      if (!out[k]) out[k] = m[2];
    }
    return out;
  }

  function cardInfo(el) {
    var p = el, n = 0, best = null;
    while (p && n < 6) {
      var cls = String(p.className || '').toLowerCase();
      if (p !== el && /(^|\s|-|_)(course|card|item)(\s|-|_|$)/.test(cls)) { best = p; break; }
      p = p.parentElement; n++;
    }
    if (!best) { try { best = el.closest('li,dl,dd,article,section') || el; } catch (e) { best = el; } }
    var txt = String(best.textContent || '').replace(/\s+/g, ' ').trim();
    return { cls: String(best.className || '').slice(0, 60), text: txt.slice(0, 90) };
  }

  function parseProgress(txt) {
    var t = String(txt || '');
    var m = t.match(/任务点进度[:：]?\s*(\d+)\s*\/\s*(\d+)/);
    if (m) return { done: Number(m[1]), total: Number(m[2]) };
    if (/已完成\s*100\s*%/.test(t)) return { done: 1, total: 1 };
    return null;
  }

  // 课名通常在卡片的 h3 / .course-name 里，cover 层只有按钮和进度
  function cardName(el) {
    var base = el.getBoundingClientRect();
    var node = el, n = 0;
    while (node && n < 4) {
      var cands = node.querySelectorAll('h1,h2,h3,h4,h5,.course-name,.courseName,.course_title,dt');
      for (var i = 0; i < cands.length; i++) {
        var rc = cands[i].getBoundingClientRect();
        // 距离锚点太远的候选多半是隔壁卡片的课名，跳过
        if (rc.width > 0 && Math.abs(rc.top - base.top) > 300) continue;
        var t = String(cands[i].getAttribute('title') || cands[i].textContent || '').replace(/\s+/g, ' ').trim();
        if (t.length >= 2 && t.length <= 40 && !/任务点进度|移动到|退课|置顶|课程已结束/.test(t)) return t;
      }
      node = node.parentElement; n++;
    }
    return '';
  }

  function scanCourses() {
    var found = [];
    eachDoc(function (doc) {
      var els = doc.querySelectorAll('a[href], [onclick]');
      for (var i = 0; i < els.length; i++) {
        var el = els[i];
        var sig = String(el.getAttribute('href') || '') + ' ' + String(el.getAttribute('onclick') || '');
        if (!/courseid=/i.test(sig)) continue;

        var pr = parseParams(sig);
        var cid = pr.courseid;
        if (!cid) continue;

        var card = cardInfo(el);
        var wide = card.text;
        if (!/任务点进度|已完成/.test(wide)) {
          try {
            var outer = el.closest('li,dl,article,section,tr');
            if (outer) wide += ' ' + String(outer.textContent || '').replace(/\s+/g, ' ').trim();
          } catch (e) { /* 忽略 */ }
        }
        found.push({
          courseId: cid,
          clazzid: pr.clazzid || '',
          cpi: pr.cpi || '',
          enc: pr.enc || '',
          openc: pr.openc || '',
          name: cardName(el),
          progress: parseProgress(wide),
          ended: /课程已结束/.test(wide),
          titleAttr: String(el.getAttribute('title') || '').trim(),
          cardCls: card.cls,
          cardText: wide.slice(0, 120),
          href: String(el.getAttribute('href') || el.getAttribute('onclick') || '').slice(0, 200)
        });
      }
    });

    var map = {}, out = [];
    found.forEach(function (x) {
      var k = x.courseId + '_' + x.clazzid;
      if (map[k]) return;
      map[k] = 1;
      out.push(x);
    });
    return out;
  }

  // 转储课程页上所有可点击元素，用于排查"点不进章节"
  function dumpEntryCandidates() {
    var rows = [];
    var ptrCount = 0;

    // 头部自检：一眼看出章节是否存在、iframe 是否跨域
    var head = [];
    head.push('URL  ' + location.href.slice(0, 160));
    head.push('a.clicktitle=' + document.querySelectorAll('a.clicktitle').length +
      '  .posCatalog=' + document.querySelectorAll('.posCatalog, .posCatalog_select').length +
      '  可见章节文字=' + (function () {
        var n = 0;
        $$('body *').forEach(function (el) {
          if (el.children.length) return;
          if (/^(\d+\.)+\d+\s*\S/.test(String(el.textContent || '').trim()) && isVisible(el)) n++;
        });
        return n;
      })());
    $$('iframe').forEach(function (f) {
      var ok = false;
      try { ok = !!f.contentDocument; } catch (e) { ok = false; }
      head.push('  iframe ' + (ok ? '[可读] ' : '[跨域] ') + String(f.src || f.id || '(无src)').slice(0, 90));
    });

    eachDoc(function (doc, depth) {
      var els = doc.querySelectorAll('a, [onclick], li, div, span');
      for (var i = 0; i < els.length && rows.length < 100; i++) {
        var el = els[i];
        if (!isVisible(el)) continue;
        var t = String(el.textContent || '').replace(/\s+/g, ' ').trim();
        if (!t || t.length > 30) continue;
        var href = el.getAttribute('href') || '';
        var oc = el.getAttribute('onclick') || '';
        var cls = String(el.className || '').trim();
        var ptr = false;
        try { ptr = doc.defaultView.getComputedStyle(el).cursor === 'pointer'; } catch (e) { ptr = false; }
        if (ptr) ptrCount++;
        // 没有 href/onclick 但鼠标是手型、或类名像章节的，也一并列出
        if (!href && !oc && !ptr && !/posCatalog|catalog|chapter|clicktitle/i.test(cls)) continue;
        rows.push('d' + depth + ' ' + el.tagName.toLowerCase() +
          (cls ? '.' + cls.split(/\s+/).join('.') : '') +
          ' :: "' + t.slice(0, 28) + '"' +
          (href ? '  href=' + href.slice(0, 70) : '') +
          (oc ? '  onclick=' + oc.slice(0, 90) : '') +
          (ptr && !oc && !href ? '  [点击区]' : ''));
      }
    });

    head.push('可点击元素 ' + ptrCount + ' 个，列出 ' + rows.length + ' 条');
    head.push('-----');
    return head.concat(rows.slice(0, 60));
  }

  function importScanned(list) {
    var added = 0, skipEnded = 0, skipDone = 0, dup = 0;
    list.forEach(function (x) {
      if (x.ended) { skipEnded++; return; }
      if (!S.incDone && x.progress && x.progress.total > 0 && x.progress.done >= x.progress.total) {
        skipDone++;
        return;
      }
      var exists = S.queue.some(function (c) {
        return String(c.courseId) === String(x.courseId) && String(c.clazzid) === String(x.clazzid);
      });
      if (exists) { dup++; return; }

      S.queue.push({
        id: x.courseId + '_' + x.clazzid,
        courseId: x.courseId,
        clazzid: x.clazzid,
        cpi: x.cpi,
        name: x.name || ('课程 ' + String(x.courseId).slice(-6)),
        nameAuto: !!x.name,
        url: x.href,
        status: 'pending',
        startedAt: 0,
        finishedAt: 0,
        leftover: null,
        reason: '',
        progress: x.progress || null
      });
      added++;
    });
    if (added) save();
    return { added: added, skipEnded: skipEnded, skipDone: skipDone, dup: dup };
  }

  function collectCurrent() {
    if (!isStudyPage()) { notify('请先进入课程学习页再收录'); return; }
    var p = new URLSearchParams(location.search);
    var courseId = urlCourseId();
    if (!courseId) { notify('当前 URL 缺少 courseId'); return; }

    var exists = S.queue.some(function (c) { return String(c.courseId) === String(courseId); });
    if (exists) { notify('这门课已经在队列里了'); return; }

    if (S.running) {
      S.running = false;
      if (S.queue[S.cursor]) S.queue[S.cursor].status = 'pending';
      log('收录新课程，队列已暂停');
    }

    var guess = guessCourseName();
    var name = guess || ('课程 ' + String(courseId).slice(-6));
    S.queue.push({
      id: courseId + '_' + (p.get('clazzid') || ''),
      courseId: courseId,
      clazzid: p.get('clazzid') || '',
      name: name,
      nameAuto: !!guess,
      url: location.href,
      status: 'pending',
      startedAt: 0,
      finishedAt: 0,
      leftover: null,
      reason: ''
    });
    save();
    log('收录课程：' + name);
    render(true);
  }

  function startQueue() {
    cancelPendingNavigation();
    if (!S.queue.length) { notify('队列为空'); return; }
    var pending = S.queue.findIndex(function (c) { return c.status !== 'done'; });
    if (pending < 0) {
      S.queue.forEach(function (c) { c.status = 'pending'; c.leftover = null; c.reason = ''; });
      pending = 0;
    }
    S.running = true;
    S.lastNav = null;
    S.navGuard = null;
    save();
    startCourse(pending);
  }

  function pauseQueue() {
    S.running = false;
    cancelPendingNavigation();
    S.navGuard = null;
    if (S.queue[S.cursor]) S.queue[S.cursor].status = 'pending';
    save();
    log('已暂停');
    render(true);
  }

  function buildReport() {
    var lines = [];
    var done = S.queue.filter(function (c) { return c.status === 'done'; }).length;
    lines.push('CX 课程联播报表');
    lines.push('生成时间：' + new Date().toLocaleString());
    lines.push('完成 ' + done + ' / ' + S.queue.length + ' 门');
    lines.push('');
    S.queue.forEach(function (c, i) {
      var dur = (c.startedAt && c.finishedAt) ? hhmmss(c.finishedAt - c.startedAt) : '-';
      lines.push((i + 1) + '. ' + c.name);
      lines.push('   状态：' + statusText(c.status) + '　耗时：' + dur +
        (c.leftover ? ('　剩余答题：' + c.leftover + ' 个') : '') +
        (c.reason ? ('　说明：' + c.reason) : ''));
    });
    return lines.join('\n');
  }

  root.addEventListener('click', function (e) {
    var t = e.target;
    if (t && t.closest) t = t.closest('[data-act]');
    var act = t && t.getAttribute && t.getAttribute('data-act');
    if (!act) return;

    if (act === 'tab') {
      uiTab = t.getAttribute('data-tab') === 'tools' ? 'tools' : 'queue';
      render(true);
    } else if (act === 'toggle') { S.running ? pauseQueue() : startQueue(); }
    else if (act === 'add') { collectCurrent(); }
    else if (act === 'min') {
      var p = root.querySelector('.panel');
      var min = p.classList.toggle('min');
      root.getElementById('btn-min').textContent = min ? '+' : '−';
    } else if (act === 'report') {
      var text = buildReport();
      try {
        if (typeof GM_setClipboard === 'function') GM_setClipboard(text, 'text');
        else navigator.clipboard.writeText(text);
      } catch (err) { /* 忽略 */ }
      alert(text);
    } else if (act === 'scan') {
      var list = scanCourses();
      if (!list.length) {
        lastScan = '本页没有找到课程链接。\n可能不在「我的课程」页面，或列表还没渲染完（刷新后再试）。';
      } else {
        var r = importScanned(list);
        lastScan = '本页共 ' + list.length + ' 门课程，新增 ' + r.added + ' 门';
        if (r.skipEnded) lastScan += '\n跳过「课程已结束」' + r.skipEnded + ' 门';
        if (r.skipDone) lastScan += '\n跳过「已完成」' + r.skipDone + ' 门';
        if (r.dup) lastScan += '\n已在队列中 ' + r.dup + ' 门';
        log('扫描课程：新增 ' + r.added + ' 门（共 ' + list.length + ' 门）');
        try {
          var dump = JSON.stringify(list, null, 1);
          if (typeof GM_setClipboard === 'function') GM_setClipboard(dump, 'text');
          else navigator.clipboard.writeText(dump);
        } catch (err) { /* 忽略 */ }
      }
      render(true);
    } else if (act === 'entdump') {
      var rows = dumpEntryCandidates();
      lastGrab = rows.length ? rows.join('\n') : '没抓到可点击元素';
      try {
        if (typeof GM_setClipboard === 'function') GM_setClipboard(lastGrab, 'text');
        else navigator.clipboard.writeText(lastGrab);
      } catch (err) { /* 忽略 */ }
      log('已抓取入口候选 ' + rows.length + ' 条');
      render(true);
    } else if (act === 'grabname') {
      var list = collectNameCandidates();
      lastGrab = list.length ? list.join('\n') : '没抓到候选元素';
      try {
        if (typeof GM_setClipboard === 'function') GM_setClipboard(lastGrab, 'text');
        else navigator.clipboard.writeText(lastGrab);
      } catch (err) { /* 忽略 */ }
      log('已抓取课名候选 ' + list.length + ' 条');
      render(true);
    } else if (act === 'restore') {
      var rs = Number(t.getAttribute('data-i'));
      var rsc = S.queue[rs];
      if (rsc) {
        rsc.status = 'pending';
        rsc.reason = '';
        rsc.leftover = null;
        rsc.finishedAt = 0;
        save();
        log('恢复为待学：' + rsc.name);
        render(true);
      }
    } else if (act === 'incdone') {
      S.incDone = !!t.checked;
      save();
      render(true);
    } else if (act === 'clearq') {
      if (!S.queue.length) return;
      if (!window.confirm('清空整个队列？此操作不可撤销。')) return;
      S.queue = [];
      S.cursor = 0;
      S.running = false;
      cancelPendingNavigation();
      S.navGuard = null;
      save();
      log('已清空队列');
      render(true);
    } else if (act === 'rename') {
      var ri = Number(t.getAttribute('data-i'));
      var rc = S.queue[ri];
      if (!rc) return;
      var nv = window.prompt('修改课程名称', rc.name);
      if (nv && nv.trim()) { rc.name = nv.trim(); rc.nameAuto = true; save(); render(true); }
    } else if (act === 'skip') {
      var i = Number(t.getAttribute('data-i'));
      if (S.queue[i]) {
        S.queue[i].status = 'done';
        S.queue[i].reason = '手动跳过';
        if (i === S.cursor && S.running) {
          cancelPendingNavigation();
          save();
          goNext();
          return;
        }
        save(); render(true);
      }
    } else if (act === 'del') {
      var j = Number(t.getAttribute('data-i'));
      S.queue.splice(j, 1);
      if (S.cursor >= S.queue.length) S.cursor = Math.max(0, S.queue.length - 1);
      save(); render(true);
    }
  });

  // ============ 启动 ============

  function boot() {
    render(true);
    if (!S.running) return;
    var cur = S.queue[S.cursor];
    if (!cur) { finishQueue(); return; }
    if (onTargetPage(cur.courseId)) {
      clearNavGuard();
      resetCourseRuntime();
      log('接管课程：' + cur.name);
      render(true);
    } else if (onCoursePage(cur.courseId)) {
      resetCourseRuntime();
      render(true);
    } else {
      navigate(cur.url, '进入队列课程');
    }
  }

  try {
    boot();
    setInterval(function () {
      try { tick(); } catch (e) { console.error('[cxq]', e); }
    }, TICK_MS);
  } catch (e) {
    console.error('[cxq] 初始化失败', e);
  }
})();