// ==UserScript==
// @name         山东省教师教育网 · 课程倍速助手（免费版）
// @namespace    lm4217
// @version      3.0.0
// @description  免费版学习辅助：后台播放，实验性的倍速播放。自动完成全部课程为独立 VIP 版，需卡密激活后使用。
// @author       lm4217
// @license      MIT
// @match        *://yxjc.qlteacher.com/project/*
// @match        *://yxjc.qlteacher.com/pre-project/*
// @match        *://player.qlteacher.com/*
// @grant        none
// @run-at       document-end
// @antifeature  payment
// @tag          山东省教育教育网
// @tag          学习辅助
// @tag          后台播放
// ==/UserScript==

(() => {
    'use strict';

    // ==================================================================
    // 免费版：只做倍速与观察，不含任何自动化学习动作。
    // 本脚本不发起任何网络请求，全部功能在本地完成。
    // 完整学习引擎是另一个独立脚本，卡密激活后由用户自行安装。
    // ==================================================================
    const BUY_URL = 'https://wzyp.cn/item/i9awt5';

    // VIP 脚本启动时会写下这个 cookie，并注入带 lcs-dot 的悬浮窗。
    // 命中任一即说明 VIP 已在工作，本脚本立刻让位，避免两个面板叠加。
    function paidRunning() {
        if (window.__LCS_PAID__) return true;
        try { if (/(?:^|; )lcs_paid=/.test(document.cookie)) return true; } catch (e) {}
        return !!document.getElementById('lcs-dot');
    }

    const projectPage = location.hostname === 'yxjc.qlteacher.com' &&
        /^\/(?:pre-)?project\/(?:yey|xx|cz|gz)20\d{2}(?:\/|$)/.test(location.pathname);
    const playerPage = location.hostname === 'player.qlteacher.com' &&
        /^\/learning(?:\/|$)/.test(location.pathname);
    if (!projectPage && !playerPage) return;
    if (document.getElementById('qlteacher-playback-helper')) return;
    if (paidRunning()) return;

    const RATES = [1,1.25,1.5,2,3,4,8,16];
    const PROBE_RATES = [2,3,4,8,16];
    const states = new WeakMap();
    let speedMode='follow';
    let requestedRate=1;
    let speedNote='';
    let probe=null;
    let validationBlocked = false;
    let scheduled = false;
    let busy = false;
    let message = '等待课程加载';
    let backgroundStarted = null;
    let backgroundStartTime = null;
    let backgroundVideo = null;
    let backgroundSource = null;
    let backgroundSeeked = false;
    let backgroundResult = '';
    let retired = false;

    const panel = document.createElement('div');
    panel.id = 'qlteacher-playback-helper';
    panel.style.cssText = 'position:fixed;right:16px;bottom:18px;z-index:2147483646;transition:bottom .3s ease;';
    const root = panel.attachShadow({mode:'open'});
    root.innerHTML = `<style>
:host{all:initial}
@keyframes slideUp{from{opacity:0;transform:translateY(24px) scale(.96)}to{opacity:1;transform:translateY(0) scale(1)}}
@keyframes pulse{0%,100%{box-shadow:0 0 4px rgba(34,197,94,.6)}50%{box-shadow:0 0 10px rgba(34,197,94,.25)}}
section{width:320px;border-radius:16px;background:rgba(255,255,255,.92);backdrop-filter:blur(24px) saturate(1.8);-webkit-backdrop-filter:blur(24px) saturate(1.8);color:#1e293b;box-shadow:0 8px 32px rgba(0,0,0,.1),0 1px 4px rgba(0,0,0,.05),inset 0 1px 0 rgba(255,255,255,.6);font:13px/1.6 -apple-system,BlinkMacSystemFont,'Segoe UI',system-ui,sans-serif;overflow:hidden;animation:slideUp .45s cubic-bezier(.16,1,.3,1)}
.hd{background:linear-gradient(135deg,#667eea 0%,#764ba2 100%);padding:14px 16px 12px;display:flex;align-items:center;gap:8px;position:relative}
.hd strong{font-size:14px;font-weight:700;color:#fff;letter-spacing:.3px;text-shadow:0 1px 3px rgba(0,0,0,.15)}
.hd-icon{font-size:18px;filter:drop-shadow(0 1px 2px rgba(0,0,0,.2))}
#collapse{position:absolute;right:12px;top:50%;transform:translateY(-50%);width:26px;height:26px;border-radius:8px;border:none;background:rgba(255,255,255,.2);color:#fff;font-size:14px;cursor:pointer;display:flex;align-items:center;justify-content:center;transition:background .2s;backdrop-filter:blur(4px);padding:0}
#collapse:hover{background:rgba(255,255,255,.35)}
.bd{padding:14px 16px 16px;transition:max-height .35s cubic-bezier(.4,0,.2,1),opacity .25s,padding .35s;max-height:600px;opacity:1;overflow:hidden}
.bd.hide{max-height:0;opacity:0;padding:0 16px}
#status{display:flex;align-items:center;gap:8px;margin:0 0 6px;font-size:13px;font-weight:600;color:#334155;overflow-wrap:anywhere}
#status::before{content:'';width:8px;height:8px;border-radius:50%;flex-shrink:0;background:#22c55e;box-shadow:0 0 4px rgba(34,197,94,.6);animation:pulse 2s ease-in-out infinite}
#status[data-s="warn"]::before{background:#f59e0b;box-shadow:0 0 6px rgba(245,158,11,.5)}
#status[data-s="err"]::before{background:#ef4444;box-shadow:0 0 6px rgba(239,68,68,.5);animation:none}
small{display:block;color:#64748b;font-size:12px;line-height:1.5;margin:2px 0}
.ctrls{display:flex;flex-wrap:wrap;gap:8px;align-items:center;margin:10px 0 8px}
label{display:flex;align-items:center;gap:5px;font-size:12px;color:#475569;font-weight:500}
select{padding:5px 24px 5px 8px;border:1.5px solid #e2e8f0;border-radius:8px;background:#f8fafc url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%2364748b' d='M3 5l3 3 3-3'/%3E%3C/svg%3E") no-repeat right 6px center;color:#334155;font-size:12px;cursor:pointer;transition:border-color .2s,box-shadow .2s;outline:none;-webkit-appearance:none;appearance:none}
select:focus{border-color:#667eea;box-shadow:0 0 0 3px rgba(102,126,234,.12)}
select:disabled{opacity:.45;cursor:default}
.btns{display:flex;gap:8px;margin-top:4px}
button{padding:7px 14px;border:none;border-radius:8px;font-size:12px;font-weight:600;cursor:pointer;transition:all .2s cubic-bezier(.4,0,.2,1);outline:none}
button:active:not(:disabled){transform:scale(.97)}
button:disabled{opacity:.4;cursor:default}
#probe{background:linear-gradient(135deg,#f093fb,#f5576c);color:#fff;box-shadow:0 2px 8px rgba(245,87,108,.25)}
#probe:hover:not(:disabled){transform:translateY(-1px);box-shadow:0 4px 14px rgba(245,87,108,.35)}
#vip{border-top:1.5px solid #e2e8f0;margin-top:12px;padding-top:12px}
#vipstate{font-size:12px;color:#64748b;overflow-wrap:anywhere;display:flex;align-items:center;gap:6px}
#vipstate::before{content:'🔒';font-size:12px}
#vipstate.on{color:#16a34a;font-weight:600}
#vipstate.on::before{content:'✅'}
#viprow{display:flex;gap:10px;align-items:center;margin-top:8px;flex-wrap:wrap}
#buy{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;box-shadow:0 2px 8px rgba(102,126,234,.25);padding:7px 16px;border-radius:8px;font-size:12px;font-weight:600;text-decoration:none;transition:all .2s cubic-bezier(.4,0,.2,1)}
#buy:hover{transform:translateY(-1px);box-shadow:0 4px 14px rgba(102,126,234,.35)}
#vipnote{display:block;color:#94a3b8;font-size:11px;line-height:1.5;margin-top:8px}
</style>
<section>
<div class="hd"><span class="hd-icon">📚</span><strong>课程倍速助手 · 免费版</strong><button type="button" id="collapse" title="收起面板">▾</button></div>
<div class="bd" id="pbody">
<p id="status"></p>
<small id="time"></small>
<small id="speed"></small>
<small id="background"></small>
<div class="ctrls">
<label>方式 <select id="mode"><option value="fixed">固定倍速</option><option value="auto">自动试速</option><option value="follow">跟随播放器</option></select></label>
<label>倍速 <select id="rate">${RATES.map(rate=>'<option value="'+rate+'">'+rate+'×</option>').join('')}</select></label>
</div>
<div class="btns">
<button type="button" id="probe">开始试速</button>
</div>
<div id="vip">
<div id="vipstate">VIP 版：未安装</div>
<div id="viprow"><a id="buy" target="_blank" rel="noopener">购买卡密</a></div>
<span id="vipnote">VIP 版是独立脚本，装好后在它的面板里输入卡密即可解锁自动串行完成全部课程。免费版只做倍速，不会自动播放或点击课程。</span>
</div>
</div>
</section>`;
    (document.body || document.documentElement).appendChild(panel);
    const status = root.getElementById('status');
    const clock = root.getElementById('time');
    const background = root.getElementById('background');
    const speed = root.getElementById('speed');
    const modeSelect = root.getElementById('mode');
    const rateSelect = root.getElementById('rate');
    const probeButton = root.getElementById('probe');
    const vipState = root.getElementById('vipstate');
    const buyLink = root.getElementById('buy');
    modeSelect.value=speedMode;
    rateSelect.value=String(requestedRate);
    buyLink.href = BUY_URL;
    const collapseBtn = root.getElementById('collapse');
    const panelBody = root.getElementById('pbody');
    let panelCollapsed = false;
    collapseBtn.addEventListener('click', () => {
        panelCollapsed = !panelCollapsed;
        panelBody.classList.toggle('hide', panelCollapsed);
        collapseBtn.textContent = panelCollapsed ? '▸' : '▾';
    });

    var observer = null;
    var timer = null;

    // VIP 脚本接管后，本脚本彻底退场：不残留面板，也不再改播放器倍速
    function retire() {
        if (retired) return;
        retired = true;
        if (probe) probe = null;
        try { observer && observer.disconnect(); } catch (e) {}
        try { clearInterval(timer); } catch (e) {}
        try { panel.remove(); } catch (e) {}
    }

    function applyRate(video, rate) {
        if (validationBlocked && rate !== 1) return false;
        const state=states.get(video);
        if (!state) return false;
        state.expectedRate=rate;
        try {
            video.playbackRate=rate;
            if (Math.abs(video.playbackRate-rate)>0.05) throw Error('Rate rejected');
            state.appliedSource=video.currentSrc || video.src;
            return true;
        } catch (error) {
            state.expectedRate=null;
            state.appliedSource=video.currentSrc || video.src;
            speedNote='播放器不支持 '+rate+'×，请降低倍速';
            return false;
        }
    }

    function stopProbe(note) {
        if (!probe) return;
        const run=probe;
        probe=null;
        speedMode='fixed';
        requestedRate=run.best;
        modeSelect.value=speedMode;
        rateSelect.value=String(requestedRate);
        applyRate(run.video,requestedRate);
        speedNote=note+'；采用 '+requestedRate+'×';
    }

    function startProbe() {
        if (validationBlocked || validationWarning()) { tick(); return; }
        const video=currentVideo();
        if (!video || video.paused || video.ended || questionOpen()) {
            speedNote='请先播放视频，再开始试速';
            render();
            return;
        }
        stopProbe('重新试速');
        speedMode='auto';
        modeSelect.value=speedMode;
        probe={video,source:video.currentSrc || video.src,index:0,best:1,sample:null};
        if (!applyRate(video,PROBE_RATES[0])) stopProbe('首档倍速不可用');
        else speedNote='试速 '+PROBE_RATES[0]+'×，每档观察至少 6 秒';
        render();
    }

    function observeSpeed(video,state) {
        const now=Date.now();
        if (video.paused || video.ended || video.seeking || questionOpen()) {
            state.sample=null;
            if (probe) stopProbe('播放中断，试速结束');
            return;
        }
        if (probe) {
            const run=probe;
            if (run.video !== video || run.source !== (video.currentSrc || video.src)) {
                stopProbe('视频已切换，试速结束');
                return;
            }
            if (!run.sample) run.sample={at:now,time:video.currentTime};
            const elapsed=(now-run.sample.at)/1000;
            if (elapsed<6) return;
            const observed=(video.currentTime-run.sample.time)/elapsed;
            const target=PROBE_RATES[run.index];
            state.measured=observed;
            if (elapsed>15 || !Number.isFinite(observed) || observed<target*0.65 || observed>target*1.3) {
                stopProbe(elapsed>15 ? '采样间隔过长，请在前台重新试速' : '当前档进度不稳定，结束试速');
                return;
            }
            run.best=target;
            run.index++;
            if (run.index>=PROBE_RATES.length) { stopProbe('试速完成'); return; }
            run.sample=null;
            const next=PROBE_RATES[run.index];
            if (!applyRate(video,next)) stopProbe('更高倍速不可用');
            else speedNote='实测 '+observed.toFixed(2)+'×；正在试 '+next+'×';
            return;
        }
        if (!state.sample) { state.sample={at:now,time:video.currentTime}; return; }
        const elapsed=(now-state.sample.at)/1000;
        if (elapsed<4) return;
        const observed=(video.currentTime-state.sample.time)/elapsed;
        state.measured=elapsed<=15 && observed>=0 ? observed : null;
        state.sample={at:now,time:video.currentTime};
    }

    function visible(el) {
        if (!el || !el.isConnected || el.hidden) return false;
        const style = getComputedStyle(el);
        return style.display !== 'none' && style.visibility !== 'hidden' && el.getClientRects().length > 0;
    }

    function currentVideo() {
        const videos = [...document.querySelectorAll('video')].filter(visible);
        return videos.find(v => !v.paused && !v.ended) || videos[0] || null;
    }

    function questionOpen() {
        const title = document.querySelector('.segmented-text-ellipsis');
        if (title && visible(title) && title.textContent.trim() === '测试题') return true;
        return [...document.querySelectorAll('[role="dialog"], .ant-modal-content')].some(el =>
            visible(el) && (el.querySelector('input[type="radio"], input[type="checkbox"], .ant-radio-input, .ant-checkbox') ||
            /测试题|请作答|请回答|单选题|多选题|提交答案/.test(el.textContent)));
    }

    function validationWarning() {
        const text=document.body?.innerText || '';
        return /(?:进度[\s\S]{0,40}(?:时长|时间)|(?:时长|时间)[\s\S]{0,40}进度)[\s\S]{0,30}(?:不符|不一致|异常)|(?:学习进度|学习时长|学习时间|学习速度)[\s\S]{0,20}异常[\s\S]{0,40}刷新/.test(text);
    }

    function stopForValidation(video) {
        validationBlocked=true;
        probe=null;
        speedMode='follow';
        requestedRate=1;
        modeSelect.value=speedMode;
        rateSelect.value='1';
        speedNote='平台要求刷新；本页倍速控制已停止';
        message='进度与学习时间校验未通过，请刷新播放器';
        if (video) {
            applyRate(video,1);
            video.pause();
            message='进度与学习时间校验未通过，请刷新播放器';
        }
    }

    function formatTime(seconds) {
        if (!Number.isFinite(seconds)) return '--:--';
        return Math.floor(seconds / 60) + ':' + String(Math.floor(seconds % 60)).padStart(2,'0');
    }

    function render() {
        status.textContent = message;
        status.dataset.s = validationBlocked ? 'err' : '';
        const video = currentVideo();
        clock.textContent = video ? formatTime(video.currentTime) + ' / ' + formatTime(video.duration) : '';
        background.textContent = backgroundResult;
        const measured=video && states.get(video)?.measured;
        speed.textContent=(video ? '当前 '+video.playbackRate+'×' : '目标 '+requestedRate+'×')+
            (Number.isFinite(measured) ? '，实测 '+measured.toFixed(2)+'×' : '')+
            (speedNote ? '；'+speedNote : '');
        rateSelect.disabled=validationBlocked || speedMode !== 'fixed';
        modeSelect.disabled=validationBlocked;
        probeButton.disabled=validationBlocked;
        probeButton.textContent=probe ? '结束试速' : '开始试速';
        renderVip();
    }

    function renderVip() {
        if (!vipState) return;
        if (paidRunning()) {
            vipState.textContent = 'VIP 版：已安装';
            vipState.className = 'on';
            buyLink.style.display = 'none';
        } else {
            vipState.textContent = 'VIP 版：未安装';
            vipState.className = '';
            buyLink.style.display = '';
        }
    }

    function stateFor(video) {
        let state = states.get(video);
        if (state) return state;
        state = {source:video.currentSrc || video.src,
            expectedRate:null,appliedSource:null,sample:null,measured:null};
        states.set(video,state);
        video.addEventListener('ratechange', () => {
            state.sample=null;
            state.measured=null;
            if (state.expectedRate !== null && Math.abs(video.playbackRate-state.expectedRate)>0.05) {
                // 尊重播放器的限制，停止试速并跟随实际速度。
                probe=null;
                speedMode='follow';
                modeSelect.value=speedMode;
                speedNote='播放器调整了倍速，已改为跟随播放器';
                state.expectedRate=null;
            }
            render();
        });
        video.addEventListener('seeking', () => {
            state.sample=null;
            state.measured=null;
            if (document.hidden) backgroundSeeked=true;
            if (probe) stopProbe('进度发生跳转，试速结束');
        });
        video.addEventListener('playing', () => {
            state.sample=null;
            message = document.hidden ? '正在后台播放' : '正在播放';
            render();
        });
        video.addEventListener('pause', () => {
            if (video.ended) return;
            message = questionOpen() ? '等待本人处理测验' : '已暂停，点击视频继续';
            queue();
        });
        video.addEventListener('ended', () => {
            message='本段视频播放结束';
            render();
        });
        video.addEventListener('timeupdate', render);
        video.addEventListener('loadedmetadata', queue);
        video.addEventListener('emptied', queue);
        return state;
    }

    function tick() {
        if (retired) return;
        // VIP 版可能在本脚本之后才注入，每轮都复查一次
        if (paidRunning()) { retire(); return; }
        if (busy) return;
        busy=true;
        try {
            const video=currentVideo();
            if (validationBlocked) { message='进度与学习时间校验未通过，请刷新播放器'; return; }
            if (validationWarning()) { stopForValidation(video); return; }
            if (questionOpen()) { if(probe)stopProbe('遇到测验，试速结束'); message='等待本人处理测验'; return; }
            if (!video) { message='请在页面上点开课程视频'; return; }
            const state=stateFor(video);
            const source=video.currentSrc || video.src;
            if (source !== state.source) {
                state.source=source;
                state.sample=null;
                state.measured=null;
            }
            if (speedMode === 'fixed' && state.appliedSource !== source) applyRate(video,requestedRate);
            observeSpeed(video,state);
            if (video.error) { message='视频加载出错，请检查网络或课程资源'; return; }
            // 只观察，不代劳：播放/暂停由使用者自己操作
            if (!video.paused && !video.ended) {
                message = document.hidden ? '正在后台播放' : '正在播放';
            } else if (video.ended) {
                message='本段视频播放结束';
            } else {
                message='已暂停，点击视频继续';
            }
        } catch (error) {
            message='页面暂未就绪，稍后重试';
            console.warn('[QL2026]',error);
        } finally {
            busy=false;
            if (!retired) render();
        }
    }

    function queue() {
        if (scheduled) return;
        scheduled=true;
        setTimeout(() => { scheduled=false; tick(); },300);
    }

    modeSelect.addEventListener('change', () => {
        if (validationBlocked || validationWarning()) { tick(); return; }
        const selected=modeSelect.value;
        if (probe) stopProbe('已切换方式');
        speedMode=selected;
        modeSelect.value=selected;
        speedNote=selected === 'auto' ? '仅比较播放速度，学时以平台记录为准；点击开始试速' : '';
        const video=currentVideo();
        if (video && selected === 'fixed') applyRate(video,requestedRate);
        if (video && selected === 'follow') stateFor(video).expectedRate=null;
        render();
    });
    rateSelect.addEventListener('change', () => {
        if (validationBlocked || validationWarning()) { tick(); return; }
        const selected=Number(rateSelect.value);
        if (!RATES.includes(selected)) return;
        if (probe) stopProbe('已选择固定倍速');
        speedMode='fixed';
        modeSelect.value=speedMode;
        requestedRate=selected;
        speedNote='';
        const video=currentVideo();
        if (video) applyRate(video,requestedRate);
        render();
    });
    probeButton.addEventListener('click', () => {
        if (validationBlocked || validationWarning()) { tick(); return; }
        if (probe) stopProbe('手动结束试速');
        else startProbe();
        render();
    });

    document.addEventListener('visibilitychange', () => {
        const video=currentVideo();
        if (document.hidden) {
            backgroundStarted=Date.now();
            backgroundStartTime=video ? video.currentTime : null;
            backgroundVideo=video;
            backgroundSource=video ? (video.currentSrc || video.src) : null;
            backgroundSeeked=false;
            if (video) stateFor(video).retries=0;
            backgroundResult='后台观察中';
        } else if (backgroundStarted !== null) {
            const elapsed=(Date.now()-backgroundStarted)/1000;
            const sameVideo=video && video === backgroundVideo && (video.currentSrc || video.src) === backgroundSource;
            const advanced=sameVideo && !backgroundSeeked && backgroundStartTime !== null ? video.currentTime-backgroundStartTime : NaN;
            backgroundResult=Number.isFinite(advanced) ?
                '上次后台 '+Math.round(elapsed)+' 秒，视频前进 '+Math.max(0,Math.round(advanced))+' 秒'+
                (elapsed>0 ? '（'+(Math.max(0,advanced)/elapsed).toFixed(2)+'×）' : '') :
                '后台期间视频已切换、跳转或当前页没有视频，请重新测试';
            backgroundStarted=null;
            backgroundStartTime=null;
            backgroundVideo=null;
            backgroundSource=null;
        }
        // 不刷新、不伪造页面可见性；让真实媒体继续播放。
        queue();
        render();
    });

    observer=new MutationObserver(queue);
    observer.observe(document.body || document.documentElement,{childList:true,subtree:true});
    timer=setInterval(tick,2000);
    window.addEventListener('pagehide', () => {
        observer.disconnect();
        clearInterval(timer);
    },{once:true});
    tick();
})();