// ==UserScript==
// @name         课享(courshare/learnspace)自动连播助手·防检测单面板版
// @namespace    https://learn.courshare.cn/
// @version      1.5.1
// @license      MIT
// @description  learn.courshare.cn 专用：单面板、跨嵌套 frame 统一找视频；固定 1x 原速；实体开关（自动播放/自动连播/静音/后台保活）+ 上/重播/下；三级导航（小节→讲→章）；功能区/日志双 Tab（日志持久化保存）；浅色文字深色底保证可读；可拖拽/折叠/悬浮球；设置自动记忆。
// @author       QYK
// @match        *://learn.courshare.cn/*
// @match        *://*.courshare.cn/*
// @run-at       document-idle
// @grant        GM_getValue
// @grant        GM_setValue
// @grant        GM_addStyle
// ==/UserScript==

/*
 * ============================================================================
 *  v1.4.0 修复"讲内多小节时自动切换总回到第一个小节"：
 *    原因：旧版把「左栏讲课」与「上方小节行(0101010000…)」当成同一层目录，
 *          且当前项判定失败时 idx=-1 仍从第 0 个开始点 → 永远切到第一个。
 *    方案：三级导航，逐级推进
 *          ① 小节行：按纯数字编码顺序，从"当前编码"往后切下一小节；
 *          ② 讲：小节行到边界后，才切左栏下一讲；
 *          ③ 章：本章讲完，才切下一章 Tab。
 *          任一当前项判定失败即"不乱点"，交给下一级，绝不盲点第一个。
 *    辅助：当前小节编码取页面中字号最大的纯数字元素（视频下方大标题）。
 *  防检测原则：固定 1x 不调速；不篡改 visibilityState（只读）；
 *    不点大播放按钮；仅自然 ended 后切节；静音为用户可控特性（默认开）。
 * ============================================================================
 */

(function () {
    'use strict';

    if (window.top !== window) return;   // 只在最顶层建唯一面板

    /* ------------------------- 存储 ------------------------- */
    const store = {
        get(key, def) {
            try {
                if (typeof GM_getValue === 'function') return GM_getValue(key, def);
                const v = localStorage.getItem('csa2_' + key);
                return v === null ? def : JSON.parse(v);
            } catch (e) { return def; }
        },
        set(key, val) {
            try {
                if (typeof GM_setValue === 'function') return GM_setValue(key, val);
                localStorage.setItem('csa2_' + key, JSON.stringify(val));
            } catch (e) {}
        }
    };

    const cfg = {
        autoNext:  store.get('autoNext',  true),   // 自动连播：播完切下一节
        autoPlay:  store.get('autoPlay',  true),   // 自动播放：被暂停自动恢复
        mute:      store.get('mute',      true),   // 静音：默认开
        keepAlive: store.get('keepAlive', true)    // 后台保活
    };

    let inited = false;
    let panel = null;
    let lastEndedAt = 0;
    let statusBadge = null, progressText = null, logListEl = null;
    let statusTimer = null;

    const $ = (sel, root) => (root || document).querySelector(sel);
    const $$ = (sel, root) => Array.from((root || document).querySelectorAll(sel));
    const clsOf = el => (el && typeof el.className === 'string') ? el.className : '';
    const isVisible = el => {
        if (!el || el.nodeType !== 1) return false;
        const r = el.getBoundingClientRect();
        if (r.width <= 0 || r.height <= 0) return false;
        const cs = getComputedStyle(el);
        return cs.display !== 'none' && cs.visibility !== 'hidden' && cs.opacity !== '0';
    };
    const fmt = s => {
        if (!isFinite(s) || s < 0) return '--:--';
        s = Math.floor(s);
        const h = Math.floor(s / 3600), m = Math.floor((s % 3600) / 60), sec = s % 60;
        const mm = String(m).padStart(2, '0'), ss = String(sec).padStart(2, '0');
        return h > 0 ? `${h}:${mm}:${ss}` : `${mm}:${ss}`;
    };
    /* ------------------------- 日志（持久化保存） ------------------------- */
    const MAX_LOG = 300;
    let logHistory = [];
    try { const h = store.get('log', []); if (Array.isArray(h)) logHistory = h.slice(-MAX_LOG); } catch (e) {}

    function pushLog(line) {
        logHistory.push(line);
        if (logHistory.length > MAX_LOG) logHistory = logHistory.slice(-MAX_LOG);
        try { store.set('log', logHistory); } catch (e) {}
    }
    function renderLog() {
        if (!logListEl) return;
        const frag = document.createDocumentFragment();
        logHistory.slice(-200).forEach(line => {
            const d = document.createElement('div');
            d.className = 'csa2-logline';
            d.textContent = line;
            frag.appendChild(d);
        });
        logListEl.innerHTML = '';
        logListEl.appendChild(frag);
        logListEl.scrollTop = logListEl.scrollHeight;
    }
    function log(msg) {
        const line = `[${new Date().toTimeString().slice(0, 8)}] ${msg}`;
        pushLog(line);
        if (logListEl) {
            const d = document.createElement('div');
            d.className = 'csa2-logline';
            d.textContent = line;
            logListEl.appendChild(d);
            while (logListEl.children.length > 200) logListEl.removeChild(logListEl.firstChild);
            logListEl.scrollTop = logListEl.scrollHeight;
        }
        console.log('%c[自动连播]', 'color:#16a34a', msg);
    }

    /* ============================================================================
     * 一、跨 frame 基础
     * ========================================================================== */
    function allDocs() {
        const docs = [document];
        const walk = win => {
            let frames;
            try { frames = win.frames; } catch (e) { return; }
            for (let i = 0; i < frames.length; i++) {
                try {
                    const d = frames[i].document;
                    if (d) { docs.push(d); walk(frames[i]); }
                } catch (e) { /* 跨域跳过 */ }
            }
        };
        walk(window);
        return docs;
    }

    function findVideos() {
        const out = [];
        allDocs().forEach(d => $$('video', d).forEach(v => { if (isVisible(v)) out.push(v); }));
        return out;
    }
    function pickMainVideo() {
        const vids = findVideos();
        let best = null;
        vids.forEach(v => { if ((v.duration || 0) > 5 && (!best || v.currentTime > 0)) best = v; });
        return best || vids[0] || null;
    }

    /* ============================================================================
     * 二、通用判定：高亮 / 当前 / 完成 / 锁定
     * ========================================================================== */
    const ACTIVE_RE = /(^|[\s_-])(active|current|selected|cur|on|is-on|playing|checked|choose)([\s_-]|$)/i;
    const DONE_RE = /done|complete|finished|learned|已完成|已学完|已学习|√|✔|✓/;
    const LOCK_RE = /lock|locked|锁|未开放|未解锁/;

    /* 高亮判定：class 命中 或 蓝色系底色（小节行/Tab 高亮多为蓝底白字） */
    function isHighlighted(el) {
        let n = el;
        for (let i = 0; i < 4 && n; i++, n = n.parentElement) {
            const cls = clsOf(n);
            if (cls && ACTIVE_RE.test(cls)) return true;
            let bg = '';
            try { bg = getComputedStyle(n).backgroundColor; } catch (e) {}
            const m = bg && bg.match(/rgba?\((\d+),\s*(\d+),\s*(\d+)(?:,\s*([\d.]+))?/);
            if (m) {
                const r = +m[1], g = +m[2], b = +m[3], a = m[4] !== undefined ? +m[4] : 1;
                if (a > 0.25 && b > 140 && b >= r + 30 && b >= g + 10) return true;
            }
        }
        return false;
    }

    /* 当前项：看自身及最多 3 层祖先的 class / aria（平台常把 active 挂外层） */
    function isActive(el) {
        let n = el;
        for (let i = 0; i < 3 && n; i++, n = n.parentElement) {
            const cls = clsOf(n);
            if (cls && ACTIVE_RE.test(cls)) return true;
            if (n.getAttribute && (n.getAttribute('aria-current') === 'true' || n.getAttribute('aria-selected') === 'true')) return true;
        }
        return false;
    }
    const isDone = el => DONE_RE.test(clsOf(el) + ' ' + (el.textContent || ''));
    const isLocked = el => LOCK_RE.test(clsOf(el) + ' ' + (el.outerHTML || ''));

    /* ============================================================================
     * 三、① 小节行导航（纯数字编码，如 0101010000）
     * ========================================================================== */
    function digitItems() {
        const out = [];
        allDocs().forEach(d => {
            $$('a,button,li,div,span', d).forEach(el => {
                const t = (el.textContent || '').trim();
                if (!/^\d{6,}$/.test(t)) return;     // 纯数字编码
                if (t.length > 24) return;           // 排除整行拼接（多个编码相连）
                if (!isVisible(el)) return;

                // 可点击性：标签 / onclick / 祖先 cursor:pointer 或语义类名
                let clickable = el.tagName === 'A' || el.tagName === 'BUTTON' || el.tagName === 'LI' || !!el.onclick;
                let n = el;
                for (let i = 0; i < 3 && n; i++, n = n.parentElement) {
                    try { if (getComputedStyle(n).cursor === 'pointer') { clickable = true; break; } } catch (e) {}
                    if (n.onclick) { clickable = true; break; }
                    if (/(^|[\s_-])(item|tab|cell|section|node|chapter|lesson|sub|point|li)([\s_-]|$)/i.test(clsOf(n))) { clickable = true; break; }
                }
                if (!clickable) return;

                const r = el.getBoundingClientRect();
                out.push({ el, code: t, r });
            });
        });
        // 去重（父子元素可能都被捕获）
        const seen = new Set(), res = [];
        out.forEach(o => {
            const k = o.code + '@' + Math.round(o.r.left) + ',' + Math.round(o.r.top);
            if (!seen.has(k)) { seen.add(k); res.push(o); }
        });
        // 先按行、再按 x 排序（小节行横向排列）
        res.sort((a, b) => (Math.round(a.r.top / 10) - Math.round(b.r.top / 10)) || (a.r.left - b.r.left));
        return res;
    }

    /* 当前小节编码：取页面中字号最大的纯数字元素（视频下方大标题） */
    function getCurrentCode() {
        let code = null, size = 0;
        allDocs().forEach(d => $$('div,span,h1,h2,h3,h4,strong,b,p,a,td', d).forEach(el => {
            const t = (el.textContent || '').trim();
            if (!/^\d{6,}$/.test(t) || t.length > 24) return;
            if (!isVisible(el)) return;
            let fs = 0;
            try { fs = parseFloat(getComputedStyle(el).fontSize) || 0; } catch (e) {}
            if (fs > size) { size = fs; code = t; }
        }));
        return code;
    }

    /* 在当前小节行内前后移动；到行边界返回 false（交给上层切讲/章） */
    function gotoSubSection(dir) {
        const items = digitItems();
        if (items.length < 2) return false;

        // 按纵向位置分行（小节行是横向排列，同一行 top 接近）
        const rows = [];
        items.forEach(o => {
            const row = rows.find(r => Math.abs(r[0].r.top - o.r.top) < 14);
            if (row) row.push(o); else rows.push([o]);
        });
        rows.forEach(r => r.sort((a, b) => a.r.left - b.r.left));

        const curCode = getCurrentCode();
        let row = null, idx = -1;

        // 优先：包含当前编码（或高亮项）且至少 2 项的 "行"
        for (const r of rows) {
            if (r.length < 2) continue;                     // 跳过孤立的大标题
            let i = curCode ? r.findIndex(o => o.code === curCode) : -1;
            if (i < 0) i = r.findIndex(o => isHighlighted(o.el));
            if (i >= 0) { row = r; idx = i; break; }
        }
        // 兜底：取项数最多的行 + 高亮项
        if (!row) {
            row = rows.filter(r => r.length >= 2).sort((a, b) => b.length - a.length)[0];
            if (!row) return false;
            idx = row.findIndex(o => isHighlighted(o.el));
            if (idx < 0) return false;                      // 判定失败：绝不盲点第一个
        }

        const target = row[idx + (dir === 'next' ? 1 : -1)];
        if (!target) return false;                          // 行首/行尾 → 交给上层

        target.el.click();
        log((dir === 'next' ? '下一小节' : '上一小节') + '：' + target.code);
        return true;
    }

    /* ============================================================================
     * 四、② 左栏"讲"目录
     * ========================================================================== */
    const ITEM_SELECTORS = [
        'a[href*="itemId"]', 'a[href*="item_id"]',
        '[onclick*="itemId"]', '[onclick*="goItem"]', '[onclick*="previewItem"]',
        'li[onclick]', '.tree li', '[class*="chapter"] li', '[class*="catalog"] li',
        '[class*="directory"] li', '[class*="outline"] li', '[class*="section"] li',
        '[class*="course-item"]', '[class*="node-item"]', '[class*="menu-item"]',
        '[class*="item"] a', '[class*="node"] a'
    ];

    function getCatalogItems() {
        const set = new Map();
        allDocs().forEach(d => {
            ITEM_SELECTORS.forEach(sel => $$(sel, d).forEach(el => {
                const txt = (el.textContent || '').trim();
                if (!txt || txt.length >= 80) return;
                if (/^\d{6,}$/.test(txt)) return;              // 排除小节编码
                if (/^第\s*\d+\s*章/.test(txt)) return;        // 排除章节 Tab
                set.set(el, txt);
            }));
        });
        return Array.from(set.keys()).filter(isVisible);
    }

    function gotoLecture(dir) {
        const items = getCatalogItems();
        if (!items.length) return false;
        let idx = items.findIndex(isActive);
        if (idx < 0) idx = items.findIndex(el => isHighlighted(el));
        if (idx < 0) return false;                             // 不乱点第一个

        const step = dir === 'next' ? 1 : -1;
        for (let k = idx + step; k >= 0 && k < items.length; k += step) {
            const el = items[k];
            if (isLocked(el)) continue;
            if (dir === 'next' && isDone(el)) continue;
            el.scrollIntoView({ block: 'nearest' });
            el.click();
            log((dir === 'next' ? '已切换到' : '已回退到') + '：' + (el.textContent || '').trim().slice(0, 30));
            return true;
        }
        return false;
    }

    /* ============================================================================
     * 五、③ 章节 Tab
     * ========================================================================== */
    function gotoChapter(dir) {
        const raw = [];
        allDocs().forEach(d => $$('a,button,li,div,span', d).forEach(el => {
            const t = (el.textContent || '').trim();
            if (!/^第\s*\d+\s*章/.test(t) || t.length > 40) return;
            if (!isVisible(el)) return;
            raw.push({ el, t, left: el.getBoundingClientRect().left });
        }));
        const seen = new Set(), list = [];
        raw.forEach(o => {
            const k = o.t + '@' + Math.round(o.left);
            if (!seen.has(k)) { seen.add(k); list.push(o); }
        });
        if (list.length < 2) return false;

        let idx = list.findIndex(o => isHighlighted(o.el));
        if (idx < 0) idx = list.findIndex(o => isActive(o.el));
        if (idx < 0) return false;

        const target = list[idx + (dir === 'next' ? 1 : -1)];
        if (!target) return false;
        target.el.click();
        log((dir === 'next' ? '下一章' : '上一章') + '：' + target.t.slice(0, 20));
        return true;
    }

    /* 播放器自带"上/下一节"按钮兜底（按文字/class 识别） */
    function clickNavButton(dir) {
        const re = dir === 'next'
            ? /下一节|下一讲|下一课|下一单元|next/iu
            : /上一节|上一讲|上一课|上一单元|prev|previous/iu;
        for (const d of allDocs()) {
            const hit = $$('a,button,div,span', d).filter(isVisible)
                .find(el => { const t = (el.textContent || '').trim(); return t.length >= 1 && t.length < 12 && re.test(t); });
            if (hit) { hit.click(); return true; }
        }
        for (const d of allDocs()) {
            const sel = dir === 'next' ? '[class*="next"]' : '[class*="prev"],[class*="previous"]';
            const btn = $(sel, d);
            if (btn && isVisible(btn)) { btn.click(); return true; }
        }
        return false;
    }

    /* 统一入口：小节 → 讲 → 原生按钮 → 章，逐级推进 */
    function advanceNav(dir) {
        if (gotoSubSection(dir)) return true;      // ① 小节行优先（修复本次问题）
        if (gotoLecture(dir)) return true;         // ② 小节走完 → 下一讲
        if (clickNavButton(dir)) return true;      // ③ 播放器原生按钮兜底
        if (gotoChapter(dir)) return true;         // ④ 本章讲完 → 下一章
        log('已到边界，未找到可切换的内容');
        return false;
    }

    /* ============================================================================
     * 六、视频绑定：只在自然 ended 后切节；被动续播按开关
     * ========================================================================== */
    function applyAudio() {
        findVideos().forEach(v => { try { v.muted = cfg.mute; } catch (e) {} });
    }

    function bindVideo(v) {
        if (!v || v.__csa2Bound) return;
        v.__csa2Bound = true;
        try { v.playbackRate = 1; } catch (e) {}     // 仅固化 1x，绝不写回其它倍速
        try { v.muted = cfg.mute; } catch (e) {}

        v.addEventListener('ended', () => {
            const now = Date.now();
            if (now - lastEndedAt < 2000) return;
            lastEndedAt = now;
            if (cfg.autoNext) {
                log('本节自然播完，切换下一节…');
                setTimeout(() => advanceNav('next'), 800);
            }
        });

        v.addEventListener('pause', () => {
            if (v.ended) return;
            setTimeout(() => {
                if (v.ended || !v.paused) return;
                const hidden = document.hidden;
                const shouldResume = cfg.autoPlay || (cfg.keepAlive && hidden);
                if (!shouldResume) return;
                if (cfg.keepAlive && hidden && !v.muted) { try { v.muted = true; } catch (e) {} }
                v.play().catch(() => {});
            }, 500);
        });
    }

    function refreshStatus() {
        findVideos().forEach(bindVideo);
        applyAudio();
        const v = pickMainVideo();
        if (!v) {
            if (statusBadge) { statusBadge.textContent = '等待视频'; statusBadge.className = 'csa2-badge idle'; }
            if (progressText) progressText.textContent = '未检测到视频';
            return;
        }
        const dur = v.duration || 0;
        const pct = dur > 0 ? Math.min(100, (v.currentTime / dur) * 100) : 0;
        if (statusBadge) {
            statusBadge.textContent = v.paused ? '已暂停' : '播放中';
            statusBadge.className = 'csa2-badge ' + (v.paused ? 'pause' : 'run');
        }
        if (progressText) progressText.textContent = `${fmt(v.currentTime)} / ${fmt(dur)}  (${pct.toFixed(1)}%)`;
    }

    /* ============================================================================
     * 七、面板
     * ========================================================================== */
    function buildPanel() {
        if (inited) return;
        inited = true;

        const css = `
        #csa2-panel{position:fixed;right:18px;bottom:96px;width:300px;z-index:2147483647;font:13px/1.55 "Microsoft YaHei",system-ui,sans-serif;color:#f1f5f9;
          background:linear-gradient(165deg,#243049 0%,#1a2233 100%);border:1px solid #3a4861;border-radius:12px;box-shadow:0 12px 38px rgba(0,0,0,.5);}
        #csa2-panel *{box-sizing:border-box;}
        #csa2-head{display:flex;align-items:center;gap:8px;padding:9px 12px;cursor:move;border-bottom:1px solid #3a4861;border-radius:12px 12px 0 0;background:linear-gradient(90deg,#0f5132,#16a34a);}
        #csa2-head .csa2-title{flex:1;font-weight:700;color:#ffffff;}
        #csa2-head .csa2-ic{width:22px;height:22px;line-height:20px;text-align:center;border-radius:6px;background:rgba(255,255,255,.18);color:#ffffff;cursor:pointer;font-size:14px;user-select:none;}
        #csa2-head .csa2-ic:hover{background:rgba(255,255,255,.34);}
        #csa2-body{padding:12px;display:flex;flex-direction:column;gap:11px;}
        .csa2-tabs{display:flex;gap:6px;}
        .csa2-tab{flex:1;padding:7px 0;border:1px solid #3a4861;background:#22304a;color:#aeb9cc;border-radius:8px;cursor:pointer;font-size:13px;font-weight:600;transition:all .15s;}
        .csa2-tab.on{background:#16a34a;border-color:#16a34a;color:#ffffff;}
        .csa2-tab:hover{filter:brightness(1.12);}
        .csa2-pane{display:flex;flex-direction:column;gap:11px;}
        .csa2-row{display:flex;align-items:center;gap:8px;flex-wrap:wrap;}
        .csa2-badge{padding:2px 9px;border-radius:99px;font-size:12px;font-weight:700;}
        .csa2-badge.run{background:#14532d;color:#86efac;}
        .csa2-badge.pause{background:#78350f;color:#fcd34d;}
        .csa2-badge.idle{background:#3a4861;color:#cbd5e1;}
        #csa2-progress{flex:1;color:#cbd5e1;font-variant-numeric:tabular-nums;font-size:12px;}
        .csa2-sec-label{color:#aeb9cc;font-size:12px;width:48px;flex:0 0 auto;}
        .csa2-fixed{padding:4px 10px;background:#22304a;color:#86efac;border:1px solid #16a34a;border-radius:7px;font-size:12px;font-weight:600;}
        .csa2-sw{display:flex;align-items:center;gap:9px;cursor:pointer;user-select:none;font-size:12.5px;color:#e2e8f0 !important;}
        .csa2-sw input{position:absolute;width:0;height:0;opacity:0;}
        .csa2-track{position:relative;width:38px;height:20px;border-radius:99px;background:#3a4861;transition:background .2s;flex:0 0 auto;}
        .csa2-knob{position:absolute;top:2px;left:2px;width:16px;height:16px;border-radius:50%;background:#f1f5f9;transition:transform .2s;box-shadow:0 1px 2px rgba(0,0,0,.4);}
        .csa2-sw input:checked + .csa2-track{background:#16a34a;}
        .csa2-sw input:checked + .csa2-track .csa2-knob{transform:translateX(18px);}
        .csa2-sw input:focus-visible + .csa2-track{box-shadow:0 0 0 2px #4ade80;}
        .csa2-sw.on{color:#86efac !important;}
        .csa2-sw-label{flex:1;line-height:1.35;color:#e2e8f0 !important;-webkit-text-fill-color:#e2e8f0 !important;}
        .csa2-sw.on .csa2-sw-label{color:#86efac !important;-webkit-text-fill-color:#86efac !important;}
        .csa2-ops{display:flex;gap:8px;}
        .csa2-ops button{flex:1;padding:8px 0;border:0;border-radius:8px;cursor:pointer;font-size:13px;font-weight:600;background:#33415a;color:#f1f5f9;transition:filter .12s, transform .05s;}
        .csa2-ops button.primary{background:#16a34a;color:#ffffff;}
        .csa2-ops button:hover{filter:brightness(1.15);}
        .csa2-ops button:active{transform:translateY(1px);}
        .csa2-loglist{max-height:210px;overflow:auto;background:#0e1626;border:1px solid #2a3754;border-radius:8px;padding:8px;font-size:11.5px;line-height:1.7;color:#aeb9cc;white-space:pre-wrap;word-break:break-all;}
        .csa2-logline{padding:1px 0;border-bottom:1px dashed #22304a;}
        .csa2-logline:last-child{border-bottom:0;}
        .csa2-logclear{align-self:flex-end;padding:5px 12px;background:#33415a;color:#f1f5f9;border:0;border-radius:7px;cursor:pointer;font-size:12px;}
        .csa2-logclear:hover{filter:brightness(1.15);}
        #csa2-ball{position:fixed;right:18px;bottom:96px;width:46px;height:46px;border-radius:50%;background:#16a34a;color:#ffffff;display:none;align-items:center;justify-content:center;z-index:2147483647;cursor:pointer;font-size:20px;box-shadow:0 8px 22px rgba(0,0,0,.45);}
        `;
        if (typeof GM_addStyle === 'function') GM_addStyle(css);
        else { const st = document.createElement('style'); st.textContent = css; document.head.appendChild(st); }

        panel = document.createElement('div');
        panel.id = 'csa2-panel';
        panel.innerHTML = `
          <div id="csa2-head">
            <span style="font-size:16px">🎓</span><span class="csa2-title">自动连播（防检测）</span>
            <span class="csa2-ic" id="csa2-fold" title="折叠">−</span>
            <span class="csa2-ic" id="csa2-hide" title="隐藏">×</span>
          </div>
          <div id="csa2-body">
            <div class="csa2-tabs">
              <button class="csa2-tab on" id="csa2-tab-func" type="button">功能区</button>
              <button class="csa2-tab" id="csa2-tab-log" type="button">日志</button>
            </div>
            <div class="csa2-pane" id="csa2-pane-func">
              <div class="csa2-row">
                <span class="csa2-badge idle" id="csa2-status">检测中</span>
                <span id="csa2-progress">--:-- / --:--</span>
              </div>
              <div class="csa2-row"><span class="csa2-sec-label">倍速</span>
                <span class="csa2-fixed">1x 原速 · 固定</span>
              </div>
              <div class="csa2-row" style="flex-direction:column;align-items:stretch;gap:9px;">
                <label class="csa2-sw"><input type="checkbox" id="t-play"><span class="csa2-track"><span class="csa2-knob"></span></span><span class="csa2-sw-label">自动播放（被暂停自动恢复）</span></label>
                <label class="csa2-sw"><input type="checkbox" id="t-next"><span class="csa2-track"><span class="csa2-knob"></span></span><span class="csa2-sw-label">自动连播（播完切下一节）</span></label>
                <label class="csa2-sw"><input type="checkbox" id="t-mute"><span class="csa2-track"><span class="csa2-knob"></span></span><span class="csa2-sw-label">静音（默认开，挂机不吵）</span></label>
                <label class="csa2-sw"><input type="checkbox" id="t-keep"><span class="csa2-track"><span class="csa2-knob"></span></span><span class="csa2-sw-label">后台保活（切标签/最小化不暂停）</span></label>
              </div>
              <div class="csa2-ops">
                <button id="b-prev" type="button">上一节</button>
                <button id="b-replay" type="button">重播</button>
                <button id="b-next" class="primary" type="button">下一节</button>
              </div>
            </div>
            <div class="csa2-pane" id="csa2-pane-log" style="display:none;">
              <div class="csa2-loglist" id="csa2-loglist"></div>
              <button class="csa2-logclear" id="csa2-logclear" type="button">清空日志</button>
            </div>
          </div>`;
        document.body.appendChild(panel);

        statusBadge = $('#csa2-status', panel);
        progressText = $('#csa2-progress', panel);
        logListEl = $('#csa2-loglist', panel);

        const bindToggle = (id, key, after) => {
            const el = $('#' + id, panel);
            el.checked = cfg[key];
            el.parentElement.classList.toggle('on', cfg[key]);
            el.onchange = () => {
                cfg[key] = el.checked; store.set(key, cfg[key]);
                el.parentElement.classList.toggle('on', el.checked);
                if (after) after();
            };
        };
        bindToggle('t-play', 'autoPlay');
        bindToggle('t-next', 'autoNext');
        bindToggle('t-mute', 'mute', applyAudio);
        bindToggle('t-keep', 'keepAlive');

        /* ---- 双 Tab 切换：功能区 / 日志 ---- */
        const tabFunc = $('#csa2-tab-func', panel);
        const tabLog = $('#csa2-tab-log', panel);
        const paneFunc = $('#csa2-pane-func', panel);
        const paneLog = $('#csa2-pane-log', panel);
        function showTab(isFunc) {
            tabFunc.classList.toggle('on', isFunc);
            tabLog.classList.toggle('on', !isFunc);
            paneFunc.style.display = isFunc ? 'flex' : 'none';
            paneLog.style.display = isFunc ? 'none' : 'flex';
            if (!isFunc) renderLog();      // 切到日志时刷新（显示已保存记录）
        }
        tabFunc.onclick = () => showTab(true);
        tabLog.onclick = () => showTab(false);

        /* ---- 清空日志（同时清掉持久化记录） ---- */
        $('#csa2-logclear', panel).onclick = () => {
            logHistory = [];
            try { store.set('log', []); } catch (e) {}
            renderLog();
            log('日志已清空');
        };

        $('#b-prev', panel).onclick = () => advanceNav('prev');
        $('#b-next', panel).onclick = () => advanceNav('next');
        $('#b-replay', panel).onclick = () => {
            const v = pickMainVideo();
            if (v) { try { v.currentTime = 0; v.play().catch(() => {}); } catch (e) {} log('已重播本节'); }
            else log('未检测到视频，无法重播');
        };

        const ball = document.createElement('div');
        ball.id = 'csa2-ball'; ball.textContent = '▶';
        document.body.appendChild(ball);
        $('#csa2-fold', panel).onclick = () => {
            const body = $('#csa2-body', panel);
            const hidden = body.style.display === 'none';
            body.style.display = hidden ? 'flex' : 'none';
            $('#csa2-fold', panel).textContent = hidden ? '−' : '+';
        };
        $('#csa2-hide', panel).onclick = () => { panel.style.display = 'none'; ball.style.display = 'flex'; };
        ball.onclick = () => { panel.style.display = 'block'; ball.style.display = 'none'; };

        /* 拖拽（关键：拖动时清掉 right/bottom，改用 left/top，避免面板被拉高、背景不跟手） */
        let sx = 0, sy = 0, ox = 0, oy = 0, dragging = false;
        $('#csa2-head', panel).addEventListener('mousedown', e => {
            if (e.target.classList.contains('csa2-ic')) return;
            dragging = true; sx = e.clientX; sy = e.clientY;
            const rect = panel.getBoundingClientRect();
            panel.style.right = 'auto';
            panel.style.bottom = 'auto';
            panel.style.left = rect.left + 'px';
            panel.style.top = rect.top + 'px';
            ox = rect.left; oy = rect.top;
            e.preventDefault();
        });
        document.addEventListener('mousemove', e => {
            if (!dragging) return;
            panel.style.left = Math.max(0, ox + e.clientX - sx) + 'px';
            panel.style.top = Math.max(0, oy + e.clientY - sy) + 'px';
        });
        document.addEventListener('mouseup', () => dragging = false);

        /* 后台保活：隐藏时被暂停 → 续播（静音方可稳过浏览器节流） */
        document.addEventListener('visibilitychange', () => {
            if (document.hidden && cfg.keepAlive) {
                const v = pickMainVideo();
                if (v && v.paused && !v.ended) {
                    if (!v.muted) { try { v.muted = true; } catch (e) {} }
                    v.play().catch(() => {});
                }
            }
        });

        applyAudio();
        renderLog();
        log('就绪：1x原速 · 静音 · 自动连播');
    }

    /* ------------------------- 启动 ------------------------- */
    let bootTries = 0;
    function boot() {
        const hasMedia = findVideos().length > 0 || getCatalogItems().length > 0 || digitItems().length > 0;
        if (hasMedia) {
            buildPanel();
            refreshStatus();
            clearInterval(statusTimer);
            statusTimer = setInterval(refreshStatus, 2000);
        } else if (++bootTries < 90) {
            setTimeout(boot, 2000);
        }
    }

    if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', boot);
    else boot();
})();