// ==UserScript==
// @name         lynda.com 字幕翻译
// @description  lynda.com 字幕翻译脚本，并支持下载视频和字幕文件
// @namespace    https://github.com/journey-ad
// @version      0.3.2.1
// @icon         https://cdn.lynda.com/static/favicon.ico
// @author       journey-ad
// @match        *://www.lynda.com/*
// @require      https://cdn.jsdelivr.net/npm/downloadjs@1.4.7/download.min.js
// @license      MIT
// @run-at       document-end
// @grant        GM_xmlhttpRequest
// @grant        GM_download
// @grant        GM_notification
// @downloadURL none
// ==/UserScript==

(function () {
    "use strict";

    var transServer = "caiyun"; // 配置翻译接口，可选值为 caiyun, sogou, google

    var entries = null;
    window.transTimer = window.setInterval(init, 100); // 用定时器检查待翻译文本是否已准备好

    function init() {
        if (unsafeWindow.mejs && getDeepProperty(mejs, "players.mep_0.selectedTrack")) {
            window.clearInterval(window.transTimer); // 清除定时器

            addTranslateBtn();
            entries = mejs.players.mep_0.selectedTrack.entries;
            Object.defineProperty(mejs.players.mep_0.selectedTrack, "entries", {
                get: function get() {
                    return entries;
                },
                set: function set(data) {
                    entries = data;

                    if (entries.text) {
                        console.log("字幕文本可用");
                        transText();
                    }
                }
            });
            console.log("字幕文本可用");
            transText();
        }
    }

    function addTranslateBtn() {
        window.isTranslateEnable = true;
        var controls = document.getElementsByClassName("mejs-controls")[0],
            css = ".mejs-container .mejs-controls .mejs-button.translate {right: 110px;}@media (min-width: 768px){.mejs-container .mejs-controls .mejs-button.translate {right: 132px;}.mejs-container .mejs-controls .mejs-button.mejs-playback-rate-button {right: 166px;}}.modal.video-modal .modal-player-cont .mejs-container .mejs-controls .mejs-button.translate {right: 90px;}#translate-btn {height: 16px;margin-top: 2px;font-size: 16px;font-weight: bold;color: #ccc;transition: all .3s;}#translate-btn:hover {color: #fff;}#translate-btn.enable {color: #ffba00;}@media (max-width: 768px){.mejs-container .mejs-captions-layer {font-size: 16px; line-height:18px;}}",
            container = document.createElement("div");

        addStyle(css);

        controls.appendChild(container);
        container.outerHTML = '<div class="mejs-button translate"><button class="enable" id="translate-btn" type="button">文</button></div>';
        var transBtn = document.getElementById("translate-btn");
        transBtn.addEventListener("click", function () {
            transBtn.classList.toggle("enable");
            window.isTranslateEnable = !window.isTranslateEnable;
        }, false);
    }

    function addDownloadTab() {
        window.loading = true;
        var courseId = unsafeWindow.lynda.courseId,
            videoId = unsafeWindow.currentVideoId,
            elVideoName = document.querySelector('#course-page .course-toc .toc-items .current .video-name'),
            videoName = '{{ index }}_{{ zh }}_{{ en }}'.render({
                index: elVideoName.dataset.index,
                en: elVideoName.dataset.original.replace(/\s+/g, '_'),
                zh: elVideoName.dataset.translate.replace(/\s+/g, '')
            }),
            panelTemplate = videoDownloadTabTemplate,
            videoData = {
                class: '',
                style: document.getElementsByClassName('tab-video-download')[0].classList.contains('selected') ? 'display:block' : 'display:none',
                subtitleNameZH: videoName + '_chs.srt',
                subtitleNameEN: videoName + '_eng.srt'
            },
            _TIMECODE_REGEX = /\[(\d+:\d+:\d+[\.,]\d+)\]/;

        getVideoUrl(courseId, videoId, function (data) {
            data[0]['qualities'].forEach(function (quality) {
                videoData['videoName' + quality] = videoName + '_' + quality + 'p.' + (quality === '64' ? 'mp3' : 'mp4');
                videoData['videoUrl' + quality] = data[0]['urls'][quality];
            });

            fixSubtitles(videoId, function (subtitles) {
                var zhSrt = '',
                    enSrt = '',
                    seqCounter = 0;

                for (var pos = 0; pos < subtitles.length - 1; pos++) {
                    var seqCurrent = subtitles[pos];
                    var mCurrent = _TIMECODE_REGEX.exec(seqCurrent['Timecode']);
                    if (mCurrent === null) continue;

                    var seqNext = subtitles[pos + 1];
                    var mNext = _TIMECODE_REGEX.exec(seqNext['Timecode']);
                    if (mNext === null) continue;

                    var appearTime = mCurrent[1].replace('.', ',').concat('0');
                    var disappearTime = mNext[1].replace('.', ',').concat('0');
                    var text = seqCurrent['Caption'].trim();

                    if (text) {
                        seqCounter++;
                        text = text.replace(/\r?\n|\r/g, " ").trim();
                        zhSrt += '{{ num }}\r\n{{ from }} --> {{ to }}\r\n{{ translate }}\r\n{{ text }}\r\n\r\n'.render({
                            num: seqCounter,
                            from: appearTime,
                            to: disappearTime,
                            translate: window.subtitleTrans[seqCounter - 1],
                            text: text
                        });
                        enSrt += '{{ num }}\r\n{{ from }} --> {{ to }}\r\n{{ text }}\r\n\r\n'.render({
                            num: seqCounter,
                            from: appearTime,
                            to: disappearTime,
                            text: text
                        });
                    }
                }

                window.downloadPanel = document.getElementById('tab-video-download');
                window.downloadPanel.outerHTML = panelTemplate.render(videoData);

                document.getElementById('tab-video-download').addEventListener('click', function (e) {
                    var el = e.target;

                    while (el.tagName !== 'LI') {
                        el = el.parentNode;
                        if (el === document.getElementById('tab-video-download')) {
                            el = null;
                            break;
                        }
                    }
                    if (el) {
                        if (el.classList.contains('subtitle')) {
                            var lang = el.dataset.lang;
                            if (lang === 'zh') {
                                download(zhSrt, videoData['subtitleNameZH'], 'text/plain');
                            } else {
                                download(enSrt, videoData['subtitleNameEN'], 'text/plain');
                            }

                        } else if (el.classList.contains('quality')) {
                            el.classList.add('disable');
                            el.classList.add('progress');
                            var elProg = el.getElementsByClassName('file-prog')[0],
                                prog = 0,
                                quality = el.dataset.quality;
                            elProg.innerText = prog + '%';

                            GM_download({
                                url: videoData['videoUrl' + quality],
                                name: videoData['videoName' + quality],
                                saveAs: true,
                                onload: function onload() {
                                    GM_notification("下载完成", videoData['videoName' + quality]);
                                    el.classList.remove('disable');
                                    el.classList.remove('progress');
                                },
                                onerror: function onerror() {
                                    GM_notification("下载失败", videoData['videoName' + quality]);
                                    el.classList.remove('disable');
                                },
                                onprogress: function onprogress(e) {
                                    prog = (e.loaded / e.total * 100).toFixed(2);
                                    elProg.innerText = prog + '%';
                                    el.style.backgroundSize = prog + '% auto';
                                }
                            });
                            GM_notification("开始下载", videoData['videoName' + quality]);
                        }
                    }
                });
                window.loading = false;
                document.getElementById('tab-video-download').classList.remove('loading');
                console.log("下载面板添加完成");
            });
        });
    }

    function getVideoUrl(courseId, videoId, callback) {
        GM_xmlhttpRequest({
            method: "GET",
            url: "https://www.lynda.com/ajax/course/".concat(courseId, "/").concat(videoId, "/play"),
            headers: {
                "accept": "application/json"
            },
            onload: function onload(response) {
                var data = JSON.parse(response.responseText);
                callback(data);
            }
        });
    }

    function fixSubtitles(videoId, callback) {
        GM_xmlhttpRequest({
            method: "GET",
            url: "https://www.lynda.com/ajax/player?videoId=".concat(videoId, "&type=transcript"),
            headers: {
                "accept": "application/json"
            },
            onload: function onload(response) {
                var data = JSON.parse(response.responseText);
                callback(data);
            }
        });
    }

    function transText() {
        document.getElementById('tab-video-download').classList.add('loading');
        window.subtitleTrans = [];
        var s = "",
            r = "",
            arr = [],
            num = 0,
            count = 0,
            subtitle = entries.text;
        subtitle.forEach(function (e) {
            // 去除每条字幕的换行符并按行排列
            s += e.replace(/\r?\n|\r/g, " ") + "\n";
        });
        num = translate(s, function (data, index) {
            // 调用翻译方法并处理回调
            count++;
            arr[index] = data; // 按分块原始下标放回结果数组

            if (count >= num) {
                // 所有翻译文本已取回
                r = arr.join("\n");
                window.subtitleTrans = r.split("\n");

                mejs.players.mep_0.displayCaptions = function () {
                    // 重写displayCaptions方法
                    var subtitle = null;

                    if ("undefined" != typeof mejs.players.mep_0.tracks) {
                        var t,
                            e = mejs.players.mep_0,
                            i = e.selectedTrack;

                        if (null !== i && i.isLoaded) {
                            for (t = 0; t < i.entries.times.length; t++) {
                                if (e.media.currentTime >= i.entries.times[t].start && e.media.currentTime <= i.entries.times[t].stop) {
                                    if (window.isTranslateEnable) {
                                        // 拼接双语字幕
                                        subtitle = (window.subtitleTrans[t] || '[等待翻译文本]') + "\n" + i.entries.text[t].replace(/\r?\n|\r/g, " ");
                                    } else {
                                        subtitle = i.entries.text[t];
                                    }

                                    return e.captionsText.html(subtitle).attr("class", "mejs-captions-text " + (i.entries.times[t].identifier || "")), void e.captions.show();
                                }
                            }

                            e.captions.hide();
                        } else e.captions.hide();
                    }
                };

                console.log(r);
                console.log("使用 " + transServer + " 翻译完成");

                if (!window.loading) {
                    addDownloadTab();
                }
            }
        });
    }

    function translate(str, callback) {
        var textArr = [],
            count = 1;

        if (str.length > 5000) {
            //大于5000字符分块翻译
            var strArr = str.split("\n"),
                i = 0;
            strArr.forEach(function (v) {
                textArr[i] = textArr[i] || "";

                if ((textArr[i] + v).length > (i + 1) * 5000) {
                    // 若加上此行后长度超出5000字符则分块
                    i++;
                    textArr[i] = "";
                }

                textArr[i] += v + "\n";
            });
            count = i + 1; // 记录块的数量
        } else {
            textArr[0] = str;
        }

        textArr.forEach(function (text, index) {
            // 遍历每块分别进行翻译
            server({
                text: text.trim(),
                index: index
            }, callback);
        });
        return count; // 返回分块数量
    }

    function server() {
        var list = {
            sogou: function sogou(r, callback) {
                var KEY = "b33bf8c58706155663d1ad5dba4192dc"; // 硬编码于搜狗网页翻译js

                var data = {
                    "from": "auto",
                    "to": "zh-CHS",
                    "client": "pc",
                    "fr": "browser_pc",
                    "text": r.text,
                    "pid": "sogou-dict-vr",
                    "useDetect": "on",
                    "useDetectResult": "on",
                    "oxford": "on",
                    "isReturnSugg": "on",
                    "needQc": 1,
                    "s": md5("autozh-CHS".concat(r.text).concat(KEY)) // 签名算法

                };
                GM_xmlhttpRequest({
                    method: "POST",
                    url: "https://fanyi.sogou.com/reventondc/translateV1",
                    headers: {
                        "accept": "application/json",
                        "content-type": "application/x-www-form-urlencoded; charset=UTF-8"
                    },
                    data: serialize(data),
                    onload: function onload(response) {
                        var result = JSON.parse(response.responseText);
                        callback(result.data.translate.dit, r.index); // 执行回调，在回调中拼接
                    }
                });
            },
            caiyun: function caiyun(r, callback) {
                var data = {
                    "source": r.text.split("\n"),
                    "trans_type": "en2zh",
                    "request_id": "web_fanyi",
                    "media": "text",
                    "os_type": "web",
                    "dict": true,
                    "cached": true,
                    "replaced": true
                };
                GM_xmlhttpRequest({
                    method: "POST",
                    url: "https://api.interpreter.caiyunai.com/v1/translator",
                    headers: {
                        "accept": "application/json",
                        "content-type": "application/json; charset=UTF-8",
                        "X-Authorization": "token:cy4fgbil24jucmh8jfr5"
                    },
                    data: JSON.stringify(data),
                    onload: function onload(response) {
                        var result = JSON.parse(response.responseText);
                        callback(result.target.join("\n"), r.index); // 执行回调，在回调中拼接
                    }
                });
            },
            google: function google(r, callback) {
                var data = {
                    "q": r.text,
                    "client": "webapp",
                    "sl": "auto",
                    "tl": "zh-CN",
                    "hl": "zh-CN",
                    "dt": "t",
                    "otf": 1,
                    "pc": 1,
                    "ssel": 0,
                    "tsel": 0,
                    "kc": 5,
                    "tk": tk(r.text)
                };
                GM_xmlhttpRequest({
                    method: "POST",
                    url: "https://translate.google.cn/translate_a/single",
                    headers: {
                        "accept": "application/json",
                        "content-type": "application/x-www-form-urlencoded; charset=UTF-8"
                    },
                    data: serialize(data),
                    onload: function onload(response) {
                        var result = JSON.parse(response.responseText),
                            arr = [];
                        result[0].forEach(function (t) {
                            t && arr.push(t[0]);
                        });
                        callback(arr.join(""), r.index); // 执行回调，在回调中拼接
                    }
                });
            }
        };

        return list[transServer].apply(null, arguments);
    }

    var liVideoDownloadTemplate = "\n<li class=\"tab-video-download\" data-tab=\"video-download\">\n    <a href=\"#tab\" id=\"video-download-tab\" aria-controls=\"tab-video-download\" tabindex=\"0\">Download</a>\n</li>";
    var videoDownloadTabTemplate = "\n<section id=\"tab-video-download\" class=\"{{ class }}\" aria-hidden=\"true\" style=\"{{ style }}\">\n    <div class=\"video-download-tab \" id=\"video-download\" tabindex=\"0\">\n        <div class=\"content unlocked\">\n            <div class=\"col-xs-12 col-sm-9\">\n                <div class=\"headline\">\n                    \u4E0B\u8F7D\u89C6\u9891\u548C\u5B57\u5E55\u6587\u4EF6\n                </div>\n                <p>\u5B57\u5E55\u6587\u4EF6\u683C\u5F0F\u4E3A.srt\uFF0C\u4E0B\u8F7D\u5728\u540E\u53F0\u8FDB\u884C\uFF0C\u8BF7\u8010\u5FC3\u7B49\u5F85</p>\n                <ul class=\"video-download-popover\">\n                    <li class=\"subtitle subtitle-zh\" data-lang=\"zh\">\n                        <a href=\"javascript:void(0)\" class=\"course-file clearfix\" tabindex=\"0\">\n                            <span class=\"file-name col-xs-8 col-sm-9 col-xl-10\">{{ subtitleNameZH }}</span>\n                            <span class=\"file-type\">[CHS]</span>\n                        </a>\n                    </li>\n                    <li class=\"subtitle subtitle-en\" data-lang=\"en\">\n                        <a href=\"javascript:void(0)\" class=\"course-file clearfix\" tabindex=\"0\">\n                            <span class=\"file-name col-xs-8 col-sm-9 col-xl-10\">{{ subtitleNameEN }}</span>\n                            <span class=\"file-type\">[ENG]</span>\n                        </a>\n                    </li>\n                    <hr>\n                    <li class=\"quality quality-720\" data-quality=\"720\">\n                        <a href=\"javascript:void(0)\" class=\"course-file clearfix\" tabindex=\"0\">\n                            <span class=\"file-name col-xs-8 col-sm-9 col-xl-10\">{{ videoName720 }}</span>\n                            <span class=\"file-prog\">-%</span>\n                            <span class=\"file-type\">[HD720P]</span>\n                        </a>\n                    </li>\n                    <li class=\"quality quality-540\" data-quality=\"540\">\n                        <a href=\"javascript:void(0)\" class=\"course-file clearfix\" tabindex=\"0\">\n                            <span class=\"file-name col-xs-8 col-sm-9 col-xl-10\">{{ videoName540 }}</span>\n                            <span class=\"file-prog\">-%</span>\n                            <span class=\"file-type\">[SD540P]</span>\n                        </a>\n                    </li>\n                    <li class=\"quality quality-360\" data-quality=\"360\">\n                        <a href=\"javascript:void(0)\" class=\"course-file clearfix\" tabindex=\"0\">\n                            <span class=\"file-name col-xs-8 col-sm-9 col-xl-10\">{{ videoName360 }}</span>\n                            <span class=\"file-prog\">-%</span>\n                            <span class=\"file-type\">[360P]</span>\n                        </a>\n                    </li>\n                    <li class=\"quality quality-64\" data-quality=\"64\">\n                        <a href=\"javascript:void(0)\" class=\"course-file clearfix\" tabindex=\"0\">\n                            <span class=\"file-name col-xs-8 col-sm-9 col-xl-10\">{{ videoName64 }}</span>\n                            <span class=\"file-prog\">-%</span>\n                            <span class=\"file-type\">[Audio]</span>\n                        </a>\n                    </li>\n                </ul>\n            </div>\n            <div class=\"hidden-xs col-sm-3\">\n                <div class=\"files unlocked\">\n                    <div>\n                        <i class=\"lyndacon project-files\"></i>\n                    </div>\n                </div>\n            </div>\n        </div>\n    </div>\n    <div class=\"video-download-disclaimer\">\n        <p>\u4E0B\u8F7D\u6B64\u6587\u4EF6\u610F\u5473\u7740\u4F60\u540C\u610F\u4F7F\u7528\u6B64\u6587\u4EF6\u7684\u884C\u4E3A\u987B\u7B26\u5408<a href=\"/aboutus/lotterms.aspx\" target=\"_blank\">\u670D\u52A1\u6761\u6B3E</a>\u4E2D\u7684\u7EA6\u5B9A\uFF0C\u4F60\u53EA\u80FD\u4EE5\u4E2A\u4EBA\u7528\u9014\u5728\u8BFE\u7A0B\u8BA2\u9605\u671F\u95F4\u89C2\u770B\u6B64\u6587\u4EF6\u4E2D\u7684\u5185\u5BB9\uFF0C\u4E0D\u5141\u8BB8\u516C\u5F00\u6216\u6563\u5E03\u6B64\u6587\u4EF6\u5185\u5BB9</p>\n    </div>\n</section>";

    function addStyle(css) {
        if (typeof GM_addStyle != "undefined") {
            GM_addStyle(css);
        } else if (typeof PRO_addStyle != "undefined") {
            PRO_addStyle(css);
        } else {
            var node = document.createElement("style");
            node.type = "text/css";
            node.appendChild(document.createTextNode(css));
            var heads = document.getElementsByTagName("head");

            if (heads.length > 0) {
                heads[0].appendChild(node);
            } else {
                // no head yet, stick it whereever
                document.documentElement.appendChild(node);
            }
        }
    }

    String.prototype.render = function (context) {
        return this.replace(/{{(.*?)}}/g, function (_match, key) {
            return context[key.trim()];
        });
    };

    Number.prototype.pad = function(size) {
        var s = String(this);
        while (s.length < (size || 2)) {s = "0" + s;}
        return s;
    }

    function getDeepProperty(obj, propstr) {
        var prop = propstr.split(".");

        for (var i = 0; i < prop.length; i++) {
            if (typeof obj === "object") obj = obj[prop[i]];
        }

        return obj;
    }

    function serialize(obj) {
        return Object.keys(obj).map(function (k) {
            return encodeURIComponent(k) + "=" + encodeURIComponent(obj[k]).replace("%20", "+");
        }).join("&");
    }

    function md5(str) {
        var k = [],
            i = 0;

        for (i = 0; i < 64;) {
            k[i] = 0 | Math.abs(Math.sin(++i)) * 4294967296;
        }

        var b,
            c,
            d,
            j,
            x = [],
            str2 = unescape(encodeURI(str)),
            a = str2.length,
            h = [b = 1732584193, c = -271733879, ~b, ~c];

        for (i = 0; i <= a;) {
            x[i >> 2] |= (str2.charCodeAt(i) || 128) << 8 * (i++ % 4);
        }

        x[str = (a + 8 >> 6) * 16 + 14] = a * 8;
        i = 0;

        for (; i < str; i += 16) {
            a = h;
            j = 0;

            for (; j < 64;) {
                a = [d = a[3], (b = a[1] | 0) + ((d = a[0] + [b & (c = a[2]) | ~b & d, d & b | ~d & c, b ^ c ^ d, c ^ (b | ~d)][a = j >> 4] + (k[j] + (x[[j, 5 * j + 1, 3 * j + 5, 7 * j][a] % 16 + i] | 0))) << (a = [7, 12, 17, 22, 5, 9, 14, 20, 4, 11, 16, 23, 6, 10, 15, 21][4 * a + j++ % 4]) | d >>> 32 - a), b, c];
            }

            for (j = 4; j;) {
                h[--j] = h[j] + a[j];
            }
        }

        str = "";

        for (; j < 32;) {
            str += (h[j >> 3] >> (1 ^ j++ & 7) * 4 & 15).toString(16);
        }

        return str;
    }

    function tk(a) {
        var tkk = "429175.1243284773",
            Jo = null,
            b,
            c,
            d;

        function Ho(a) {
            return function () {
                return a;
            };
        }

        function Io(a, b) {
            for (var c = 0; c < b.length - 2; c += 3) {
                var d = b.charAt(c + 2);
                d = "a" <= d ? d.charCodeAt(0) - 87 : Number(d);
                d = "+" == b.charAt(c + 1) ? a >>> d : a << d;
                a = "+" == b.charAt(c) ? a + d & 4294967295 : a ^ d;
            }

            return a;
        }

        if (null !== Jo) b = Jo; else {
            b = Ho(String.fromCharCode(84));
            c = Ho(String.fromCharCode(75));
            b = [b(), b()];
            b[1] = c();
            b = (Jo = tkk || "") || "";
        }
        d = Ho(String.fromCharCode(116));
        c = Ho(String.fromCharCode(107));
        d = [d(), d()];
        d[1] = c();
        d = b.split(".");
        b = Number(d[0]) || 0;

        for (var e = [], f = 0, g = 0; g < a.length; g++) {
            var k = a.charCodeAt(g);
            128 > k ? e[f++] = k : (2048 > k ? e[f++] = k >> 6 | 192 : (55296 == (k & 64512) && g + 1 < a.length && 56320 == (a.charCodeAt(g + 1) & 64512) ? (k = 65536 + ((k & 1023) << 10) + (a.charCodeAt(++g) & 1023), e[f++] = k >> 18 | 240, e[f++] = k >> 12 & 63 | 128) : e[f++] = k >> 12 | 224, e[f++] = k >> 6 & 63 | 128), e[f++] = k & 63 | 128);
        }

        a = b;

        for (f = 0; f < e.length; f++) {
            a += e[f], a = Io(a, "+-a^+6");
        }

        a = Io(a, "+-3^+b+-f");
        a ^= Number(d[1]) || 0;
        0 > a && (a = (a & 2147483647) + 2147483648);
        a %= 1E6;
        return a.toString() + "." + (a ^ b);
    }

    (function () { // 翻译目录&添加下载面板HTML
        var videoNameList = document.querySelectorAll('.video-name'),
            s = [],
            r = [];

        videoNameList.forEach(function (videoName, i) {
            s[i] = videoName.innerText;
        });

        translate(s.join('\n'), function (data) {
            r = data.split('\n');
            videoNameList.forEach(function (videoName, i) {
                videoName.dataset.index = i.pad(2),
                videoName.dataset.original = videoName.innerText;
                videoName.dataset.translate = r[i];
                videoName.innerText = r[i] + ' (' + videoName.innerText + ')';
            });
        });

        // 添加下载面板HTML
        var css = '.video-download-tab{position:relative}.video-download-tab.fade .content{max-height:300px;padding-bottom:30px}.video-download-tab .content{max-height:338px;min-height:220px;overflow-y:auto;padding:30px 20px;}.video-download-tab .content .col-xs-6{position:static}.video-download-tab .content.locked{min-height:280px}.video-download-tab .content.unlocked li a:hover{background:#f7f7f7;text-decoration:none}.video-download-tab .headline{font-size:15px;font-weight:700;line-height:18px}.video-download-tab hr{margin:6px 0;}.video-download-tab .video-download-popover+.headline{margin-top:10px}.video-download-tab p{line-height:30px;margin:0}.video-download-tab li.disable{pointer-events:none;opacity:.5;}.video-download-tab li.progress{border-radius:6px;background:linear-gradient(#eee,#eee);background-size:0% auto;background-repeat:no-repeat;}.video-download-tab li .file-prog{display:none;}.video-download-tab li.progress .file-prog{display:inline-block;}.video-download-tab .quality-64 a .file-type{color:#9E9E9E;}.video-download-tab .quality-720 a .file-type,.video-download-tab .subtitle-zh a .file-type{color:#4ec57d;}.video-download-tab li a,.video-download-tab li>span{display:block;line-height:1em;padding:10px}.video-download-tab li a .lock,.video-download-tab li>span .lock{color:#999;font-size:10px;margin:-3px 0 0 -13px;vertical-align:text-top}.video-download-tab li a .file-type,.video-download-tab li>span .file-type{float:right;font-weight:bold;color:#4e5bc5;}.video-download-tab li a .file-name,.video-download-tab li>span .file-name{display:inline-block;line-height:1em;max-width:610px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;}.video-download-tab .files{margin-top:5px;text-align:center;z-index:2;float:right;margin-right:15px}.video-download-tab .files.unlocked .project-files{color:#ddd}.video-download-tab .files .project-files{color:#666;font-size:120px}.video-download-tab .files .discover{font-size:17px;line-height:21px}.video-download-tab .files button{display:block;margin-top:15px;width:100%}.video-download-disclaimer{margin-top:20px;border-top:2px solid #eee;padding:20px 30px}.video-download-disclaimer p{line-height:1.4em;margin-bottom:0}#tab-video-download.loading{pointer-events:none;}#tab-video-download.loading .video-download-tab .content{overflow:hidden;}#tab-video-download.loading p,#tab-video-download.loading span,#tab-video-download.loading .headline,#tab-video-download.loading .video-download-disclaimer a{box-sizing:border-box;color:transparent;background:#eee;padding:6px;}#tab-video-download.loading .video-download-disclaimer a,#tab-video-download.loading .headline{display:none;}#tab-video-download.loading p,#tab-video-download.loading span.file-name{box-sizing:border-box;color:transparent;background:#eee;padding:15px;margin:10px 0;animation-duration:2s;animation-fill-mode:forwards;animation-iteration-count:infinite;animation-name:placeHolderShimmer;animation-timing-function:linear;background:#f6f7f8;background:linear-gradient(to right,#eeeeee 8%,#dddddd 18%,#eeeeee 33%);background-size:1400px 100px;}#tab-video-download.loading span.file-name{padding:6px;margin:0;}@keyframes placeHolderShimmer{0%{background-position:-200px 0}33%,100%{background-position:900px 0}}';
        addStyle(css);
        window.downloadTab = document.createElement('li');
        document.getElementById('course-tabs').appendChild(window.downloadTab);
        window.downloadTab.outerHTML = liVideoDownloadTemplate;

        window.downloadPanel = document.createElement('section');
        document.getElementsByClassName('tab-container')[0].appendChild(window.downloadPanel);
        window.downloadPanel.outerHTML = videoDownloadTabTemplate.render({
            class: 'loading',
            style: document.getElementsByClassName('tab-video-download')[0].classList.contains('selected') ? 'display:block' : 'display:none'
        });
        window.downloadPanel = document.getElementById('tab-video-download');
    })();
})();