// ==UserScript==
// @name         学习通自动刷课助手
// @namespace    http://tampermonkey.net/
// @version      1.0.0
// @description  学习通(超星)自动刷课：自动播放视频、倍速播放、自动切下一节、自动答题、防挂机模拟、学习进度面板。需配合油猴(Tampermonkey)使用。
// @author       you
// @match        *://*.chaoxing.com/*
// @match        *://*.xueyinonline.com/*
// @match        *://*.edu.cn/*
// @grant        none
// @run-at       document-start
// @license      MIT
// ==/UserScript==

(function () {
    'use strict';

    /* ================================================================
     * 0. 激活范围：仅在“学习通”相关页面运行
     * ================================================================ */
    const HOST = location.hostname;
    const PATH = location.pathname;
    const ACTIVE =
        /chaoxing|xueyinonline/i.test(HOST) ||
        /mooc-ans|\/knowledge\/|videoPlay|doHomeWorkNew|doWorkAnswer|exam\//i.test(PATH);
    if (!ACTIVE) return;

    const IS_TOP = (() => { try { return window === window.top; } catch (e) { return false; } })();
    const SPEED_LIST = [1, 1.5, 2, 3, 4, 8, 16];

    /* ================================================================
     * 1. 配置（localStorage 持久化）
     * ================================================================ */
    const LS_KEY = 'cx_shuake_cfg_v1';
    const defaultCfg = {
        speed: 16,          // 默认倍速
        autoMute: true,     // 自动静音
        autoNext: true,     // 自动切下一节
        autoAnswer: true,   // 自动答题
        autoSubmit: false,  // 答完是否直接提交(默认只保存，更安全)
        answerMode: 'first',// first | random | skip
        antiIdle: true      // 防挂机模拟
    };
    let cfg = Object.assign({}, defaultCfg);
    try { Object.assign(cfg, JSON.parse(localStorage.getItem(LS_KEY) || '{}')); } catch (e) {}
    function saveCfg() { try { localStorage.setItem(LS_KEY, JSON.stringify(cfg)); } catch (e) {} }

    let running = true;      // 总开关

    /* ================================================================
     * 2. 日志
     * ================================================================ */
    const logs = [];
    function log(msg) {
        const t = new Date().toLocaleTimeString('zh-CN', { hour12: false });
        logs.push('[' + t + '] ' + msg);
        if (logs.length > 60) logs.shift();
        try {
            const le = document.getElementById('cxsh-log');
            if (le) le.textContent = logs.slice(-9).join('\n');
        } catch (e) {}
        console.log('[学习通刷课]', msg);
    }

    /* ================================================================
     * 3. 跨窗口收集（同源 iframe 全部可见）
     * ================================================================ */
    function collectWindows() {
        const seen = new Set();
        const queue = [];
        try { queue.push(window.top); } catch (e) { queue.push(window); }
        while (queue.length) {
            const w = queue.shift();
            if (!w || seen.has(w)) continue;
            seen.add(w);
            try {
                const fs = w.document.querySelectorAll('iframe, frame');
                for (const f of fs) {
                    try { if (f.contentWindow) queue.push(f.contentWindow); } catch (e) {}
                }
            } catch (e) {}
        }
        return Array.from(seen);
    }
    function collectDocs() {
        const out = [];
        for (const w of collectWindows()) {
            try { out.push(w.document); } catch (e) {}
        }
        return out;
    }

    /* ================================================================
     * 4. 视频：查找 + 倍速 + 自动播放 + 静音
     * ================================================================ */
    function findVideo() {
        let best = null, bestScore = -1;
        for (const d of collectDocs()) {
            let vs;
            try { vs = d.querySelectorAll('video'); } catch (e) { continue; }
            for (const v of vs) {
                let s = 0;
                if (v.duration && isFinite(v.duration) && v.duration > 0) s += 10;
                if (v.id === 'video_html5_api' || /video-js|vjs-tech/.test(v.className || '')) s += 5;
                if (v.clientWidth > 200 && v.clientHeight > 100) s += 3;
                try { if (v.offsetParent !== null) s += 2; } catch (e) {}
                if (!v.paused) s += 2;
                if (s > bestScore) { bestScore = s; best = { doc: d, video: v }; }
            }
        }
        return best;
    }

    function enforceVideo() {
        const ctx = findVideo();
        if (!ctx) return null;
        const v = ctx.video;
        try {
            const spd = Math.min(16, Math.max(1, cfg.speed));
            if (v.playbackRate !== spd) v.playbackRate = spd;
            if (cfg.autoMute && !v.muted) { v.muted = true; }
            if (v.paused && !v.ended && v.readyState > 0) {
                const p = v.play();
                if (p && p.catch) p.catch(() => {});
            }
        } catch (e) {}
        return ctx;
    }

    function attachVideoEvents(ctx) {
        const v = ctx.video;
        if (v.__cxWatched) return;
        v.__cxWatched = true;
        v.addEventListener('ended', () => {
            log('视频播放完成');
            if (!cfg.autoNext) return;
            if (IS_TOP) setTimeout(() => clickNext('ended'), 800);
            else {
                try { window.parent.postMessage({ type: 'cx-next' }, '*'); } catch (e) {}
            }
        });
    }

    /* ================================================================
     * 5. 自动切下一节（顶部页面负责；子窗口发消息请求）
     * ================================================================ */
    let lastNextAt = 0;
    function clickNext(reason) {
        const now = Date.now();
        if (now - lastNextAt < 2000) return false;   // 防重复
        lastNextAt = now;

        // 策略1：常见按钮选择器
        const sels = [
            '#nextBtn', '.next_btn', '.nextBtn', '.btn-next', '.next', 'a.next',
            '.next-section', '.nextB', '.icon-xiayibu', '.btn-next-step'
        ];
        for (const d of collectDocs()) {
            for (const sel of sels) {
                const els = d.querySelectorAll(sel);
                for (const el of els) {
                    if (el.disabled) continue;
                    const r = el.getBoundingClientRect();
                    if (r.width === 0 || r.height === 0 || r.width > 500) continue;
                    try { el.click(); log('已点击切集按钮(' + sel + ')'); return true; } catch (e) {}
                }
            }
        }
        // 策略2：文本匹配按钮
        for (const d of collectDocs()) {
            const btn = findBtnByText(d, ['下一节', '下一集', '下节', '下一任务点', '下一个', '继续下一']);
            if (btn) {
                try { btn.click(); log('已点击「' + (btn.textContent || '').trim().slice(0, 10) + '」'); return true; } catch (e) {}
            }
        }
        // 策略3：侧边栏目录，当前章节的下一项
        for (const d of collectDocs()) {
            const cur = d.querySelector(
                '.ncells h4.currents, .ncells .currents, .chapter_item.cur, .chapter_item .cur, .active .chapter_item'
            );
            if (!cur) continue;
            const item = cur.closest('.ncells, .chapter_item, li');
            if (!item) continue;
            const next = item.nextElementSibling;
            const link = next ? next.querySelector('a, h4 a, .title, .name') : null;
            if (link) {
                try { link.click(); log('已点击目录下一节「' + (link.textContent || '').trim().slice(0, 14) + '」'); return true; } catch (e) {}
            }
        }
        log('未找到下一节入口（' + (reason || 'auto') + '）');
        return false;
    }

    // 子窗口发来的切集请求
    window.addEventListener('message', (e) => {
        try {
            const d = e.data || {};
            if (d.type === 'cx-next') clickNext('frame-msg');
        } catch (err) {}
    });

    /* ================================================================
     * 6. 自动答题（章节测验 / 作业 / 考试）
     * ================================================================ */
    const QUIZ_URL = /doHomeWorkNew|doWorkAnswer|reVersionTestStartNew|test\/|exam\/|work\/|examTest|doExam/i;
    function isQuizPage() {
        if (QUIZ_URL.test(location.href)) return true;
        return collectDocs().some(d => !!d.querySelector('#submitTest, .qtContent, .mark_item, #submitTestContent, .workContent'));
    }

    let saveClickedFor = '';   // 记录已保存的页面 URL，避免重复点
    function handleQuiz() {
        if (!cfg.autoAnswer || !isQuizPage()) return;
        for (const d of collectDocs()) {
            const qs = d.querySelectorAll('.questionLi, .mark_item, .TiMu, .questionItem');
            if (!qs.length) continue;

            // 找一题未作答的客观题作答（每个周期只处理一题，避免过快）
            for (const q of qs) {
                const inputs = q.querySelectorAll('input[type=radio], input[type=checkbox]');
                if (!inputs.length) continue;               // 填空/主观题跳过
                let hasChecked = false;
                for (const i of inputs) if (i.checked) { hasChecked = true; break; }
                if (hasChecked) continue;
                const arr = Array.from(inputs);
                const pick = cfg.answerMode === 'skip' ? null
                    : (cfg.answerMode === 'random' ? arr[Math.floor(Math.random() * arr.length)] : arr[0]);
                if (pick) {
                    const target = pick.closest('label') || pick.closest('.optionUl li') || pick.closest('.answerBg') || pick.parentElement || pick;
                    try { target.click(); log('已作答一题（第' + (arr.indexOf(pick) + 1) + '个选项）'); }
                    catch (e) { try { pick.click(); } catch (e2) {} }
                }
                return;
            }

            // 全部答完 → 保存 / 提交
            const key = location.href.split('#')[0];
            if (saveClickedFor === key) return;
            if (cfg.autoSubmit) {
                const sub = findBtnByText(d, ['提交作业', '交卷', '提交答卷', '提交']);
                if (sub) { sub.click(); saveClickedFor = key; log('已点击提交'); return; }
            }
            const save = findBtnByText(d, ['保存']);
            if (save) { save.click(); saveClickedFor = key; log('已点击保存'); }
            return;
        }
    }

    // 视频播放中途出现的题目
    function handleVideoQuiz() {
        if (!cfg.autoAnswer) return;
        for (const d of collectDocs()) {
            const box = d.querySelector('.ans-videoquiz-opts, .videoquiz, .ans-quiz-opts');
            if (!box || box.offsetParent === null) continue;
            const opts = box.querySelectorAll('input[type=radio]');
            let done = false;
            for (const o of opts) {
                if (String(o.value).toLowerCase() === 'true') { try { o.click(); done = true; break; } catch (e) {} }
            }
            if (!done && opts.length) { try { opts[0].click(); } catch (e) {} }
            const sub = box.querySelector('.ans-videoquiz-submit, .submit, button[type=submit]');
            if (sub) { try { sub.click(); log('已提交视频中题目'); } catch (e) {} }
        }
    }

    // 按文本找按钮（返回可点击元素）
    function findBtnByText(d, texts) {
        const els = d.querySelectorAll('button, a, [role="button"], .btn, .ant-btn, .layui-btn, .el-button, .btn-next, input[type=button]');
        for (const b of els) {
            const t = (b.textContent || '').trim().replace(/\s+/g, '');
            if (!t) continue;
            for (const tx of texts) {
                if (t === tx || t.indexOf(tx) === 0) {
                    const r = b.getBoundingClientRect();
                    if (r.width === 0 || r.height === 0 || r.width > 500) continue;
                    return b;
                }
            }
        }
        return null;
    }

    /* ================================================================
     * 7. 拖拽验证码 / 弹窗处理
     * ================================================================ */
    function solveDragCaptcha() {
        for (const d of collectDocs()) {
            const slider = d.querySelector(
                '.drag-btn, .drag_btn, .yidun_slider, .sc-btn, .dragVerify .btn, .dragverify-btn, #dragVerify .drag-btn, .verify-slider, .nc_iconfont.btn_slide'
            );
            if (!slider) continue;
            const lastTry = slider.__cxTryAt || 0;
            if (Date.now() - lastTry < 30000) continue;   // 失败后 30s 再重试
            slider.__cxTryAt = Date.now();
            const track = slider.closest('.drag, .yidun_slider__track, .sc_track, .dragVerify, .yidun, .verify-slider-wrap') || slider.parentElement;
            if (!track) continue;

            const tr = track.getBoundingClientRect();
            const sr = slider.getBoundingClientRect();
            const sx = sr.left + sr.width / 2;
            const sy = sr.top + sr.height / 2;
            const ex = Math.max(sr.left, tr.right - 8);
            const fire = (type, x, y) => {
                const opt = { bubbles: true, cancelable: true, clientX: x, clientY: y, button: 0 };
                try { d.dispatchEvent(new MouseEvent(type, opt)); } catch (e) {}
                try { window.dispatchEvent(new MouseEvent(type, opt)); } catch (e) {}
                try { slider.dispatchEvent(new MouseEvent(type, opt)); } catch (e) {}
            };
            fire('mousedown', sx, sy);
            const steps = 25;
            for (let i = 1; i <= steps; i++) {
                fire('mousemove', sx + (ex - sx) * i / steps, sy + Math.sin(i / steps * Math.PI) * 2);
            }
            fire('mouseup', ex, sy);
            log('已尝试拖动验证码滑块');
            return; // 一次处理一个
        }
    }

    const POPUP_OK = ['确定', '知道了', '好的', '关闭', '我知道了', '进入下一节', '继续学习', '开始学习', '下一步', '跳过', '略过', '不再提醒'];
    function closePopups() {
        for (const d of collectDocs()) {
            const dialogs = d.querySelectorAll('.layui-layer, .el-message-box, .ant-modal, .ui-dialog, .layermchild, .popup, .dialog, .modal, .layui-layer-dialog');
            for (const dl of dialogs) {
                if (dl.offsetParent === null) continue;
                const btn = findBtnByText(dl, POPUP_OK);
                if (btn) {
                    try { btn.click(); log('已关闭弹窗'); } catch (e) {}
                    return;
                }
            }
        }
    }

    /* ================================================================
     * 8. 防挂机：模拟鼠标活动 + 伪装页面可见
     * ================================================================ */
    let lastActivity = 0;
    function simulateActivity() {
        const now = Date.now();
        if (now - lastActivity < 20000) return;
        lastActivity = now;
        const x = 100 + Math.random() * 300;
        const y = 100 + Math.random() * 300;
        try {
            document.dispatchEvent(new MouseEvent('mousemove', { bubbles: true, cancelable: true, clientX: x, clientY: y }));
            document.dispatchEvent(new MouseEvent('mousedown', { bubbles: true, cancelable: true, clientX: x, clientY: y }));
        } catch (e) {}
        for (const w of collectWindows()) {
            try { w.document.dispatchEvent(new MouseEvent('mousemove', { bubbles: true, clientX: x, clientY: y })); } catch (e) {}
        }
    }

    function overrideVisibility(win) {
        try {
            win.eval(`(function () {
                try {
                    Object.defineProperty(document, 'hidden', { configurable: true, get: function () { return false; } });
                    Object.defineProperty(document, 'webkitHidden', { configurable: true, get: function () { return false; } });
                    Object.defineProperty(document, 'visibilityState', { configurable: true, get: function () { return 'visible'; } });
                } catch (e) {}
            })()`);
        } catch (e) {}
    }

    /* ================================================================
     * 9. 进度面板 UI（仅在顶层页面创建）
     * ================================================================ */
    let panel = null;
    const PANEL_CSS =
        '#cxsh-panel{position:fixed;right:16px;top:120px;z-index:2147483647;width:250px;font:12px/1.5 "Microsoft YaHei",sans-serif;' +
        'background:rgba(24,32,58,.96);color:#e8ecf5;border:1px solid rgba(255,255,255,.14);border-radius:10px;' +
        'box-shadow:0 8px 30px rgba(0,0,0,.4);overflow:hidden;-webkit-user-select:none;user-select:none;}' +
        '#cxsh-panel .cxsh-h{display:flex;justify-content:space-between;align-items:center;padding:8px 12px;cursor:move;' +
        'background:rgba(64,86,255,.35);font-weight:700;letter-spacing:.5px;}' +
        '#cxsh-panel .cxsh-min{cursor:pointer;font-weight:400;padding:0 4px;}' +
        '#cxsh-panel .cxsh-b{padding:10px 12px;}' +
        '#cxsh-panel .cxsh-row{margin:6px 0;display:flex;align-items:center;gap:6px;flex-wrap:wrap;}' +
        '#cxsh-panel .cxsh-tag{background:rgba(64,86,255,.5);padding:1px 8px;border-radius:4px;font-weight:700;}' +
        '#cxsh-panel button{background:rgba(255,255,255,.12);color:#e8ecf5;border:1px solid rgba(255,255,255,.2);' +
        'border-radius:6px;padding:3px 10px;cursor:pointer;font-size:12px;}' +
        '#cxsh-panel button:hover{background:rgba(255,255,255,.22);}' +
        '#cxsh-panel button.cxsh-on{background:rgba(52,199,89,.85);border-color:transparent;color:#0b3d1e;font-weight:700;}' +
        '#cxsh-panel label{display:flex;align-items:center;gap:4px;margin-right:10px;cursor:pointer;}' +
        '#cxsh-panel .cxsh-bar{height:6px;background:rgba(255,255,255,.12);border-radius:3px;overflow:hidden;flex:1;}' +
        '#cxsh-panel .cxsh-bar i{display:block;height:100%;width:0;background:linear-gradient(90deg,#4f7cff,#38e08b);transition:width .4s;}' +
        '#cxsh-panel .cxsh-ch{margin:4px 0;color:#9fb0d4;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;}' +
        '#cxsh-panel .cxsh-log{margin:8px 0 0;padding:6px 8px;background:rgba(0,0,0,.35);border-radius:6px;' +
        'max-height:130px;overflow:auto;white-space:pre-wrap;word-break:break-all;color:#9fb0d4;font-size:11px;line-height:1.5;}' +
        '#cxsh-panel .cxsh-danger{background:rgba(255,69,58,.85)!important;color:#fff!important;border-color:transparent!important;font-weight:700;}';

    function createPanel() {
        if (!IS_TOP || panel) return;
        if (!document.body) return;

        const st = document.createElement('style');
        st.textContent = PANEL_CSS;
        (document.head || document.documentElement).appendChild(st);

        const el = document.createElement('div');
        el.id = 'cxsh-panel';
        el.innerHTML =
            '<div class="cxsh-h">学习通自动刷课 <span class="cxsh-min" id="cxsh-min">—</span></div>' +
            '<div class="cxsh-b">' +
            '  <div class="cxsh-row"><span class="cxsh-tag" id="cxsh-status">运行中</span>' +
            '    <button id="cxsh-toggle" class="cxsh-on">暂停</button>' +
            '    <button id="cxsh-nextbtn">下一节</button></div>' +
            '  <div class="cxsh-row"><span class="cxsh-tag" style="background:rgba(159,176,212,.25)">视频</span>' +
            '    <span class="cxsh-bar"><i id="cxsh-bar"></i></span><span id="cxsh-pct">-</span></div>' +
            '  <div class="cxsh-row"><span class="cxsh-tag" style="background:rgba(159,176,212,.25)">章节</span>' +
            '    <span class="cxsh-ch" id="cxsh-ch">-</span></div>' +
            '  <div class="cxsh-row">倍速 <button id="cxsh-sd">-</button><span class="cxsh-tag" id="cxsh-speed">' + cfg.speed + 'x</span><button id="cxsh-su">+</button></div>' +
            '  <div class="cxsh-row">' +
            '    <label><input type="checkbox" id="cxsh-c-next"> 切集</label>' +
            '    <label><input type="checkbox" id="cxsh-c-ans"> 答题</label>' +
            '    <label><input type="checkbox" id="cxsh-c-idle"> 防挂机</label></div>' +
            '  <pre class="cxsh-log" id="cxsh-log"></pre>' +
            '</div>';
        document.body.appendChild(el);

        // 拖拽
        const head = el.querySelector('.cxsh-h');
        head.addEventListener('mousedown', (e) => {
            e.preventDefault();
            const ox = e.clientX - el.offsetLeft, oy = e.clientY - el.offsetTop;
            const mv = (ev) => {
                el.style.left = Math.max(0, ev.clientX - ox) + 'px';
                el.style.top = Math.max(0, ev.clientY - oy) + 'px';
                el.style.right = 'auto';
            };
            const up = () => { window.removeEventListener('mousemove', mv); window.removeEventListener('mouseup', up); };
            window.addEventListener('mousemove', mv);
            window.addEventListener('mouseup', up);
        });
        el.querySelector('#cxsh-min').addEventListener('click', () => {
            const b = el.querySelector('.cxsh-b');
            b.style.display = b.style.display === 'none' ? '' : 'none';
        });

        // 控件
        el.querySelector('#cxsh-toggle').addEventListener('click', function () {
            running = !running;
            this.textContent = running ? '暂停' : '继续';
            this.classList.toggle('cxsh-on', running);
            el.querySelector('#cxsh-status').textContent = running ? '运行中' : '已暂停';
            log(running ? '已启动' : '已暂停');
        });
        el.querySelector('#cxsh-nextbtn').addEventListener('click', () => clickNext('manual'));
        el.querySelector('#cxsh-sd').addEventListener('click', () => setSpeedIdx(SPEED_LIST.indexOf(cfg.speed) - 1));
        el.querySelector('#cxsh-su').addEventListener('click', () => setSpeedIdx(SPEED_LIST.indexOf(cfg.speed) + 1));
        const bindCfg = (id, key) => {
            const box = el.querySelector(id);
            box.checked = cfg[key];
            box.addEventListener('change', () => { cfg[key] = box.checked; saveCfg(); log('配置已更新'); });
        };
        bindCfg('#cxsh-c-next', 'autoNext');
        bindCfg('#cxsh-c-ans', 'autoAnswer');
        bindCfg('#cxsh-c-idle', 'antiIdle');

        panel = { el, pctEl: el.querySelector('#cxsh-pct'), barEl: el.querySelector('#cxsh-bar'), chEl: el.querySelector('#cxsh-ch'), speedEl: el.querySelector('#cxsh-speed') };
        log('面板已加载，自动刷课开始');
    }

    function setSpeedIdx(i) {
        if (i < 0 || i >= SPEED_LIST.length) return;
        cfg.speed = SPEED_LIST[i];
        saveCfg();
        if (panel) panel.speedEl.textContent = cfg.speed + 'x';
        log('倍速已设为 ' + cfg.speed + 'x');
    }

    function setPanelProgress(pct) {
        if (!panel) return;
        panel.pctEl.textContent = (pct >= 0 ? pct : '-') + '%';
        panel.barEl.style.width = Math.min(100, Math.max(0, pct)) + '%';
    }

    function getChapterName() {
        for (const d of collectDocs()) {
            const el = d.querySelector('.ncells h4.currents, .currents, .chapter_item.cur, .chapter_item .cur, .active .chapter_item, .knowledge-title, .card-title, .name-title');
            if (el) { const t = (el.textContent || '').trim().replace(/\s+/g, ' '); if (t) return t; }
        }
        return document.title || '-';
    }

    /* ================================================================
     * 10. 主循环
     * ================================================================ */
    let lastNextAtAuto = 0;
    function tick() {
        try {
            // 面板懒创建
            if (IS_TOP && !panel && document.body) createPanel();

            if (IS_TOP) overrideVisibility(window);

            if (!running) return;

            // 伪装可见性（覆盖所有同源窗口）
            for (const w of collectWindows()) overrideVisibility(w);

            // 视频控制
            const ctx = enforceVideo();
            if (ctx) {
                attachVideoEvents(ctx);
                const v = ctx.video;
                if (v.duration && isFinite(v.duration)) {
                    const pct = Math.min(100, Math.round(v.currentTime / v.duration * 100));
                    setPanelProgress(pct);
                    if (IS_TOP && panel) {
                        panel.chEl.textContent = getChapterName();
                    }
                    // ended 未触发时兜底（播放结束被暂停）
                    if (v.ended || (v.paused && v.currentTime >= v.duration - 0.5)) {
                        if (cfg.autoNext && Date.now() - lastNextAtAuto > 4000) {
                            lastNextAtAuto = Date.now();
                            if (IS_TOP) clickNext('ended-fallback');
                            else { try { window.parent.postMessage({ type: 'cx-next' }, '*'); } catch (e) {} }
                        }
                    }
                }
            } else if (IS_TOP && panel) {
                panel.chEl.textContent = getChapterName();
                setPanelProgress(-1);
            }

            // 答题 & 验证码 & 弹窗 & 防挂机
            if (cfg.autoAnswer) { handleVideoQuiz(); handleQuiz(); }
            if (cfg.antiIdle) simulateActivity();
            solveDragCaptcha();
            closePopups();

        } catch (e) {
            console.error('[学习通刷课]', e);
        }
    }

    setInterval(tick, 1000);
    tick();
})();