Netflix - subtitle downloader

Allows you to download subtitles from Netflix

当前为 2020-09-26 提交的版本,查看 最新版本

您需要先安装一个扩展,例如 篡改猴Greasemonkey暴力猴,之后才能安装此脚本。

You will need to install an extension such as Tampermonkey to install this script.

您需要先安装一个扩展,例如 篡改猴暴力猴,之后才能安装此脚本。

您需要先安装一个扩展,例如 篡改猴Userscripts ,之后才能安装此脚本。

您需要先安装一款用户脚本管理器扩展,例如 Tampermonkey,才能安装此脚本。

您需要先安装用户脚本管理器扩展后才能安装此脚本。

(我已经安装了用户脚本管理器,让我安装!)

您需要先安装一款用户样式管理器扩展,比如 Stylus,才能安装此样式。

您需要先安装一款用户样式管理器扩展,比如 Stylus,才能安装此样式。

您需要先安装一款用户样式管理器扩展,比如 Stylus,才能安装此样式。

您需要先安装一款用户样式管理器扩展后才能安装此样式。

您需要先安装一款用户样式管理器扩展后才能安装此样式。

您需要先安装一款用户样式管理器扩展后才能安装此样式。

(我已经安装了用户样式管理器,让我安装!)

// ==UserScript==
// @name        Netflix - subtitle downloader
// @description Allows you to download subtitles from Netflix
// @license     MIT
// @version     3.4.2
// @namespace   tithen-firion.github.io
// @include     https://www.netflix.com/*
// @grant       unsafeWindow
// @require     https://cdn.jsdelivr.net/gh/Stuk/jszip@579beb1d45c8d586d8be4411d5b2e48dea018c06/dist/jszip.min.js?version=3.1.5
// @require     https://cdn.jsdelivr.net/gh/eligrey/FileSaver.js@283f438c31776b622670be002caf1986c40ce90c/dist/FileSaver.min.js?version=2018-12-29
// ==/UserScript==

class ProgressBar { 
  constructor(max) {
    this.current = 0;
    this.max = max;

    let container = document.querySelector('#userscript_progress_bars');
    if(container === null) {
      container = document.createElement('div');
      container.id = 'userscript_progress_bars'
      document.body.appendChild(container)
      container.style
      container.style.position = 'fixed';
      container.style.top = 0;
      container.style.left = 0;
      container.style.width = '100%';
      container.style.background = 'red';
      container.style.zIndex = '99999999';
    }

    this.progressElement = document.createElement('div');
    this.progressElement.innerHTML = 'Click to stop';
    this.progressElement.style.cursor = 'pointer';
    this.progressElement.style.fontSize = '16px';
    this.progressElement.style.textAlign = 'center';
    this.progressElement.style.width = '100%';
    this.progressElement.style.height = '20px';
    this.progressElement.style.background = 'transparent';
    this.stop = new Promise(resolve => {
      this.progressElement.addEventListener('click', () => {resolve(STOP_THE_DOWNLOAD)});
    });

    container.appendChild(this.progressElement);
  }

  increment() {
    this.current += 1;
    if(this.current <= this.max) {
      let p = this.current / this.max * 100;
      this.progressElement.style.background = `linear-gradient(to right, green ${p}%, transparent ${p}%)`;
    }
  }

  destroy() {
    this.progressElement.remove();
  }
}

const STOP_THE_DOWNLOAD = 'NETFLIX_SUBTITLE_DOWNLOADER_STOP_THE_DOWNLOAD';
const MAIN_TITLE = '.player-status-main-title, .ellipsize-text>h4, .video-title>h4';
const TRACK_MENU = '#player-menu-track-settings, .audio-subtitle-controller';
const NEXT_EPISODE = '.player-next-episode:not(.player-hidden), .button-nfplayerNextEpisode';

const WEBVTT = 'webvtt-lssdh-ios8';
const DFXP = 'dfxp-ls-sdh';
const SIMPLE = 'simplesdh';
const ALL_FORMATS = [WEBVTT, DFXP, SIMPLE];

const FORMAT_NAMES = {};
FORMAT_NAMES[WEBVTT] = 'WebVTT';
FORMAT_NAMES[DFXP] = 'DFXP/XML';

const EXTENSIONS = {};
EXTENSIONS[WEBVTT] = 'vtt';
EXTENSIONS[DFXP] = 'dfxp';
EXTENSIONS[SIMPLE] = 'xml';

const DOWNLOAD_MENU = `<lh class="list-header">Netflix subtitle downloader</lh>
<li class="list-header">Netflix subtitle downloader</li>
<li class="track download">Download subs for this episode</li>
<li class="track download-all">Download subs from this ep till last available</li>
<li class="track force-all-lang">Force Netflix to show all languages: <span></span></li>
<li class="track lang-setting">Languages to download: <span></span></li>
<li class="track sub-format">Subtitle format: prefer <span></span></li>`;

const SCRIPT_CSS = `.player-timed-text-tracks, .track-list-subtitles{ border-right:1px solid #000 }
.player-timed-text-tracks+.player-timed-text-tracks, .track-list-subtitles+.track-list-subtitles{ border-right:0 }
.subtitle-downloader-menu { list-style:none }
#player-menu-track-settings .subtitle-downloader-menu li.list-header,
.audio-subtitle-controller .subtitle-downloader-menu lh.list-header{ display:none }`;

const SUB_TYPES = {
  'subtitles': '',
  'closedcaptions': '[cc]'
};

let idOverrides = {};
let zip;
let subCache = {};
let batch = false;

let forceSubs = localStorage.getItem('NSD_force-all-lang') !== 'false';
let langs = localStorage.getItem('NSD_lang-setting') || '';
let subFormat = localStorage.getItem('NSD_sub-format') || WEBVTT;

const setForceText = () => {
  document.querySelector('.subtitle-downloader-menu > .force-all-lang > span').innerHTML = (forceSubs ? 'on' : 'off');
};
const setLangsText = () => {
  document.querySelector('.subtitle-downloader-menu > .lang-setting > span').innerHTML = (langs === '' ? 'all' : langs);
};
const setFormatText = () => {
  document.querySelector('.subtitle-downloader-menu > .sub-format > span').innerHTML = FORMAT_NAMES[subFormat];
};

const toggleForceLang = () => {
  forceSubs = !forceSubs;
  if(forceSubs)
    localStorage.removeItem('NSD_force-all-lang');
  else
    localStorage.setItem('NSD_force-all-lang', forceSubs);
  document.location.reload();
};
const setLangToDownload = () => {
  const result = prompt('Languages to download, comma separated. Leave empty to download all subtitles.\nExample: en,de,fr', langs);
  if(result !== null) {
    langs = result;
    if(langs === '')
      localStorage.removeItem('NSD_lang-setting');
    else
      localStorage.setItem('NSD_lang-setting', langs);
    setLangsText();
  }
};
const setSubFormat = () => {
  if(subFormat === WEBVTT) {
    localStorage.setItem('NSD_sub-format', DFXP);
    subFormat = DFXP;
  }
  else {
    localStorage.removeItem('NSD_sub-format');
    subFormat = WEBVTT;
  }
  setFormatText();
};

const asyncSleep = (seconds, value) => new Promise(resolve => {
  window.setTimeout(resolve, seconds * 1000, value);
});

const popRandomElement = arr => {
  return arr.splice(arr.length * Math.random() << 0, 1)[0];
};

// get show name or full name with episode number
const __getTitle = full => {
  if(typeof full === 'undefined')
    full = true;
  const titleElement = document.querySelector(MAIN_TITLE);
  if(titleElement === null)
    return null;
  const title = [titleElement.textContent.replace(/[:*?"<>|\\\/]+/g, '_').replace(/ /g, '.')];
  if(full) {
    const episodeElement = titleElement.nextElementSibling;
    if(episodeElement) {
      const m = episodeElement.textContent.match(/^[^\d]*(\d+)[^\d]+(\d+)[^\d]*$/);
      if(m && m.length == 3) {
        title.push(`S${m[1].padStart(2, '0')}E${m[2].padStart(2, '0')}`);
      }
      else {
        title.push(episodeElement.textContent.trim().replace(/[:*?"<>|\\\/]+/g, '_').replace(/ /g, '.'));
      }
    }
    title.push('WEBRip.Netflix');
  }
  return title.join('.');
};
// helper function, periodically checking for the title and resolving promise if found
const _getTitle = (full, resolve) => {
  const title = __getTitle(full);
  if(title === null)
    window.setTimeout(_getTitle, 200, full, resolve);
  else
    resolve(title);
};
// promise of a title
const getTitle = full => new Promise(resolve => {
  _getTitle(full, resolve);
});

const processSubInfo = async result => {
  const tracks = result.timedtexttracks;
  const titleP = getTitle();
  const subs = {};
  for(const track of tracks) {
    if(track.isNoneTrack)
      continue;

    let type = SUB_TYPES[track.rawTrackType];
    if(typeof type === 'undefined')
      type = `[${track.rawTrackType}]`;
    const lang = track.language + type + (track.isForcedNarrative ? '-forced' : '');

    const formats = {};
    for(let format of ALL_FORMATS) {
      if(typeof track.ttDownloadables[format] !== 'undefined')
        formats[format] = [Object.values(track.ttDownloadables[format].downloadUrls), EXTENSIONS[format]];
    }

    if(Object.keys(formats).length > 0)
      subs[lang] = formats;
  }
  subCache[result.movieId] = {titleP, subs};

  if(batch) {
    downloadAll();
  }
};

const getSubsFromCache = () => {
  const id = window.location.pathname.split('/').pop();
  if(subCache.hasOwnProperty(id))
    return subCache[id];

  let newID = undefined;
  try {
    newID = unsafeWindow.netflix.falcorCache.videos[id].current.value[1];
  }
  catch(ignore) {}
  if(typeof newID !== 'undefined' && subCache.hasOwnProperty(newID))
    return subCache[newID];

  newID = idOverrides[id];
  if(typeof newID !== 'undefined' && subCache.hasOwnProperty(newID))
    return subCache[newID];

  alert("Couldn't find subs, try refreshing the page.");
  throw '';
};

const pickFormat = formats => {
  const preferred = ALL_FORMATS.slice();
  if(subFormat === DFXP)
    preferred.push(preferred.shift());

  for(let format of preferred) {
    if(typeof formats[format] !== 'undefined')
      return formats[format];
  }
};


const _save = async (_zip, title) => {
  const content = await _zip.generateAsync({type:'blob'});
  saveAs(content, title + '.zip');
};

const _download = async _zip => {
  const showTitle = getTitle(false);
  const {titleP, subs} = getSubsFromCache();
  const downloaded = [];

  let filteredLangs;
  if(langs === '')
    filteredLangs = Object.keys(subs);
  else {
    const regularExpression = new RegExp('^(' + langs.replace(/\-/g, '\\-').replace(/\s/g, '').replace(/,/g, '|') + ')');
    filteredLangs = [];
    for(const lang of Object.keys(subs)) {
      if(lang.match(regularExpression))
        filteredLangs.push(lang);
    }
  }

  const progress = new ProgressBar(filteredLangs.length);
  let stop = false;
  for(const lang of filteredLangs) {
    const [urls, extension] = pickFormat(subs[lang]);
    while(urls.length > 0) {
      let url = popRandomElement(urls);
      const resultPromise = fetch(url, {mode: "cors"});
      let result;
      try {
        // Promise.any isn't supported in all browsers, use Promise.race instead
        result = await Promise.race([resultPromise, progress.stop, asyncSleep(30, STOP_THE_DOWNLOAD)]);
      }
      catch(e) {
        // the only promise that can be rejected is the one from fetch
        // if that happens we want to stop the download anyway
        result = STOP_THE_DOWNLOAD;
      }
      if(result === STOP_THE_DOWNLOAD) {
        stop = true;
        break;
      }
      progress.increment();
      const data = await result.text();
      if(data.length > 0) {
        downloaded.push({lang, data, extension});
        break;
      }
    }
    if(stop)
      break;
  }
  const title = await titleP;

  downloaded.forEach(x => {
    const {lang, data, extension} = x;
    _zip.file(`${title}.${lang}.${extension}`, data);
  });

  if(await Promise.race([progress.stop, {}]) === STOP_THE_DOWNLOAD)
    stop = true;
  progress.destroy();

  return [await showTitle, stop];
};

const downloadThis = async () => {
  const _zip = new JSZip();
  const [showTitle, stop] = await _download(_zip);
  _save(_zip, showTitle);
};

const downloadAll = async () => {
  zip = zip || new JSZip();
  batch = true;
  const [showTitle, stop] = await _download(zip);
  const nextEp = document.querySelector(NEXT_EPISODE);
  if(!stop && nextEp)
    nextEp.click();
  else {
    await _save(zip, showTitle);
    zip = undefined;
    batch = false;
  }
};

const processMessage = e => {
  const override = e.detail.id_override;
  if(typeof override !== 'undefined')
    idOverrides[override[0]] = override[1];
  else
    processSubInfo(e.detail);
}

const injection = () => {
  const WEBVTT = 'webvtt-lssdh-ios8';
  const MANIFEST_URL = "manifest";
  const forceSubs = localStorage.getItem('NSD_force-all-lang') !== 'false';

  // hijack JSON.parse and JSON.stringify functions
  ((parse, stringify) => {
    JSON.parse = function (text) {
      const data = parse(text);
      if (data && data.result && data.result.timedtexttracks && data.result.movieId) {
        window.dispatchEvent(new CustomEvent('netflix_sub_downloader_data', {detail: data.result}));
      }
      return data;
    };
    JSON.stringify = function (data) {
      if (data && typeof data.url === 'string' && data.url.indexOf(MANIFEST_URL) > -1) {
        for (let v of Object.values(data)) {
          try {
            if (v.profiles)
              v.profiles.unshift(WEBVTT);
            if (v.showAllSubDubTracks != null && forceSubs)
              v.showAllSubDubTracks = true;
          }
          catch (e) {
            if (e instanceof TypeError)
              continue;
            else
              throw e;
          }
        }
      }
      if(data && typeof data.movieId === 'number') {
        try {
          let videoId = data.params.sessionParams.uiplaycontext.video_id;
          if(typeof videoId === 'number' && videoId !== data.movieId)
            window.dispatchEvent(new CustomEvent('netflix_sub_downloader_data', {detail: {id_override: [videoId, data.movieId]}}));
        }
        catch(ignore) {}
      }
      return stringify(data);
    };
  })(JSON.parse, JSON.stringify);
}

window.addEventListener('netflix_sub_downloader_data', processMessage, false);

// inject script
const sc = document.createElement('script');
sc.innerHTML = '(' + injection.toString() + ')()';
document.head.appendChild(sc);
document.head.removeChild(sc);

// add CSS style
const s = document.createElement('style');
s.innerHTML = SCRIPT_CSS;
document.head.appendChild(s);

// add menu when it's not there
const observer = new MutationObserver(function(mutations) {
  mutations.forEach(function(mutation) {
    mutation.addedNodes.forEach(function(node) {
      if(node.nodeName.toUpperCase() == 'DIV') {
        let trackMenu = (node.parentNode || node).querySelector(TRACK_MENU);
        if(trackMenu !== null && trackMenu.querySelector('.subtitle-downloader-menu') === null) {
          let ol = document.createElement('ol');
          ol.setAttribute('class', 'subtitle-downloader-menu player-timed-text-tracks track-list track-list-subtitles');
          ol.innerHTML = DOWNLOAD_MENU;
          trackMenu.appendChild(ol);
          ol.querySelector('.download').addEventListener('click', downloadThis);
          ol.querySelector('.download-all').addEventListener('click', downloadAll);
          ol.querySelector('.force-all-lang').addEventListener('click', toggleForceLang);
          ol.querySelector('.lang-setting').addEventListener('click', setLangToDownload);
          ol.querySelector('.sub-format').addEventListener('click', setSubFormat);
          setForceText();
          setLangsText();
          setFormatText();
        }
      }
    });
  });
});
observer.observe(document.body, { childList: true, subtree: true });