// ==UserScript==
// @name         课程伴侣视频自动播放助手
// @namespace    http://tampermonkey.net/
// @version      1.1
// @description  自动播放视频，默认静音，显示实时进度（反馈群：612441267）
// @author       lakay666
// @match        https://mooc.ytu.edu.cn/meol/jpk/course/layout/newpage/index.jsp?courseId=*
// @match        https://mooc.ytu.edu.cn/meol/jpk/course/layout/newpage/index.jsp*
// @grant        none
// @run-at       document-end
// ==/UserScript==

(function() {
    'use strict';

    var CHECK_INTERVAL = 2000;
    var DEBUG = true;

    function log(msg) {
        if (DEBUG) console.log('[YTU助手] ' + msg);
    }

    function getCtx() {
        try {
            var f1 = document.querySelector('iframe#mainFrame');
            if (!f1) return null;
            var d1 = f1.contentDocument || f1.contentWindow.document;
            var f2 = d1.querySelector('iframe#main-content-two');
            if (!f2) return null;
            var w2 = f2.contentWindow;
            var d2 = f2.contentDocument || w2.document;
            return { win: w2, doc: d2 };
        } catch (e) {
            return null;
        }
    }

    function parseTime(s) {
        if (!s) return 0;
        var p = s.split(':');
        if (p.length === 3) return parseInt(p[0])*3600 + parseInt(p[1])*60 + parseInt(p[2]);
        if (p.length === 2) return parseInt(p[0])*60 + parseInt(p[1]);
        return 0;
    }

    function fmtTime(sec) {
        if (!sec || sec < 0) return '00:00:00';
        var h = Math.floor(sec/3600);
        var m = Math.floor((sec%3600)/60);
        var s = Math.floor(sec%60);
        return (h<10?'0'+h:h) + ':' + (m<10?'0'+m:m) + ':' + (s<10?'0'+s:s);
    }

    function getTimes(ctx) {
        if (!ctx || !ctx.doc) return null;
        var els = ctx.doc.querySelectorAll('div, span');
        var re = /^(\d{1,2}:\d{2}:\d{2})\/(\d{1,2}:\d{2}:\d{2})$/;
        for (var i = 0; i < els.length; i++) {
            var t = els[i].textContent ? els[i].textContent.trim() : '';
            var m = t.match(re);
            if (m) {
                return {
                    cur: parseTime(m[1]),
                    tot: parseTime(m[2]),
                    raw: t
                };
            }
        }
        return null;
    }

    function simClick(el, ctx) {
        if (!el || !ctx) return false;
        try {
            var r = el.getBoundingClientRect();
            var x = r.left + r.width/2;
            var y = r.top + r.height/2;
            var w = ctx.win;
            var types = ['mouseover', 'mousedown', 'mouseup', 'click'];
            for (var i = 0; i < types.length; i++) {
                el.dispatchEvent(new w.MouseEvent(types[i], {
                    bubbles: true, cancelable: true, view: w,
                    clientX: x, clientY: y, button: 0
                }));
            }
            return true;
        } catch (e) {
            return false;
        }
    }

    function clickPlay(ctx) {
        if (!ctx || !ctx.doc) return false;
        var btn = ctx.doc.querySelector('div[data-title="点击播放"]');
        if (btn) {
            var st = ctx.win.getComputedStyle(btn);
            if (st.display !== 'none') {
                log('点击播放');
                return simClick(btn, ctx);
            }
        }
        return false;
    }

    function clickMute(ctx) {
        if (!ctx || !ctx.doc) return false;
        var btn = ctx.doc.querySelector('div[data-title="静音"]');
        if (btn) {
            var st = ctx.win.getComputedStyle(btn);
            if (st.display !== 'none') {
                log('点击静音');
                return simClick(btn, ctx);
            }
        }
        return true;
    }

    var lastTime = 0;
    var stuck = 0;
    var hasMuted = false;
    var hasStarted = false;
    var timer = null;

    function updatePanel(cur, tot) {
        var c = document.getElementById('ytu-cur');
        var t = document.getElementById('ytu-tot');
        var f = document.getElementById('ytu-fill');
        var info = document.getElementById('ytu-info');
        if (c) c.textContent = fmtTime(cur);
        if (t) t.textContent = fmtTime(tot);
        if (f && tot > 0) f.style.width = (cur/tot*100).toFixed(1) + '%';
        if (info) info.textContent = fmtTime(cur) + ' / ' + fmtTime(tot);
    }

    function tick() {
        var ctx = getCtx();
        if (!ctx) {
            log('等待iframe加载...');
            return;
        }
        var times = getTimes(ctx);
        if (!times) return;

        log('进度: ' + times.raw);
        updatePanel(times.cur, times.tot);

        var playing = times.cur > 0 && times.cur < times.tot;
        if (playing) {
            if (times.cur === lastTime) {
                stuck++;
                if (stuck > 3) {
                    log('卡住，重试播放');
                    stuck = 0;
                    clickPlay(ctx);
                }
            } else {
                stuck = 0;
            }
            lastTime = times.cur;
            if (!hasMuted) {
                clickMute(ctx);
                hasMuted = true;
            }
        } else if (!hasStarted) {
            log('开始播放');
            clickPlay(ctx);
            hasStarted = true;
        }
    }

    function start() {
        log('助手已启动');
        timer = setInterval(tick, CHECK_INTERVAL);
    }

    function stop() {
        if (timer) {
            clearInterval(timer);
            timer = null;
        }
        lastTime = 0;
        stuck = 0;
        hasMuted = false;
        hasStarted = false;
    }

    function createPanel() {
        var p = document.createElement('div');
        p.id = 'ytu-panel';
        p.innerHTML = '<div style="position:fixed;top:80px;right:20px;width:240px;background:rgba(0,0,0,0.85);color:#fff;border-radius:8px;padding:12px;font-size:13px;z-index:99999;font-family:Microsoft YaHei,sans-serif;box-shadow:0 4px 12px rgba(0,0,0,0.3);cursor:move;user-select:none;">' +
            '<div style="display:flex;align-items:center;justify-content:space-between;margin-bottom:10px;">' +
            '<span style="font-weight:bold;color:#4CAF50;">YTU视频助手</span>' +
            '<span style="font-size:11px;color:#aaa;">运行中</span>' +
            '</div>' +
            '<div style="margin-bottom:10px;padding:8px;background:rgba(255,255,255,0.1);border-radius:4px;">' +
            '<div style="font-size:11px;color:#aaa;margin-bottom:4px;">播放进度</div>' +
            '<div style="width:100%;height:6px;background:rgba(255,255,255,0.2);border-radius:3px;overflow:hidden;margin-bottom:4px;">' +
            '<div id="ytu-fill" style="width:0%;height:100%;background:#4CAF50;transition:width 0.5s;"></div>' +
            '</div>' +
            '<div style="display:flex;justify-content:space-between;font-size:11px;color:#ddd;">' +
            '<span id="ytu-cur">00:00:00</span>' +
            '<span id="ytu-tot">00:00:00</span>' +
            '</div>' +
            '</div>' +
            '<div style="display:flex;gap:6px;">' +
            '<button id="ytu-play" style="flex:1;padding:5px 8px;border:none;border-radius:4px;background:#4CAF50;color:#fff;cursor:pointer;font-size:12px;">播放</button>' +
            '<button id="ytu-mute" style="flex:1;padding:5px 8px;border:none;border-radius:4px;background:#FF9800;color:#fff;cursor:pointer;font-size:12px;">静音</button>' +
            '</div>' +
            '<div id="ytu-info" style="margin-top:8px;padding-top:8px;border-top:1px solid #444;font-size:11px;color:#bbb;">等待视频加载...</div>' +
            '</div>';
        document.body.appendChild(p);

        document.getElementById('ytu-play').addEventListener('click', function() {
            var ctx = getCtx();
            if (ctx) clickPlay(ctx);
        });
        document.getElementById('ytu-mute').addEventListener('click', function() {
            var ctx = getCtx();
            if (ctx) clickMute(ctx);
        });

        var drag = false;
        var sx, sy, sl, st;
        var c = p.firstElementChild;
        c.addEventListener('mousedown', function(e) {
            drag = true;
            sx = e.clientX;
            sy = e.clientY;
            var r = c.getBoundingClientRect();
            sl = r.left;
            st = r.top;
        });
        document.addEventListener('mousemove', function(e) {
            if (!drag) return;
            c.style.left = (sl + e.clientX - sx) + 'px';
            c.style.top = (st + e.clientY - sy) + 'px';
            c.style.right = 'auto';
        });
        document.addEventListener('mouseup', function() {
            drag = false;
        });
    }

    function init() {
        createPanel();
        start();
        window.addEventListener('beforeunload', stop);
    }

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