Netflix - subtitle downloader

Allows you to download subtitles from Netflix

当前为 2021-09-11 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     4.0.1
// @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 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 = `<li class="header">Netflix subtitle downloader</li>
<li class="download">Download subs for this episode</li>
<!--<li class="download-all">Download subs from this ep till last available</li>-->
<li class="ep-title-in-filename">Add episode title to filename: <span></span></li>
<li class="force-all-lang">Force Netflix to show all languages: <span></span></li>
<li class="lang-setting">Languages to download: <span></span></li>
<li class="sub-format">Subtitle format: prefer <span></span></li>`;

const SCRIPT_CSS = `
.subtitle-downloader-menu {
  list-style: none;
  position: relative;
  display: none;
  width: 300px;
  background: #333;
  color: #fff;
  padding: 0;
  margin: auto;
  font-size: 12px;
}
body:hover .subtitle-downloader-menu { display: block; }
.subtitle-downloader-menu li { padding: 10px; }
.subtitle-downloader-menu li.header { font-weight: bold; }
.subtitle-downloader-menu li:not(.header):hover { background: #666; }
.subtitle-downloader-menu li:not(.header) {
  display: none;
  cursor: pointer;
}
.subtitle-downloader-menu:hover li { display: block; }
`;

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

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

let epTitleInFilename = localStorage.getItem('NSD_ep-title-in-filename') === 'true';
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 setEpTitleInFilename = () => {
  document.querySelector('.subtitle-downloader-menu > .ep-title-in-filename > span').innerHTML = (epTitleInFilename ? 'on' : 'off');
};
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 toggleEpTitleInFilename = () => {
  epTitleInFilename = !epTitleInFilename;
  if(epTitleInFilename)
    localStorage.setItem('NSD_ep-title-in-filename', epTitleInFilename);
  else
    localStorage.removeItem('NSD_ep-title-in-filename');
  setEpTitleInFilename();
};
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];
};

const processSubInfo = async result => {
  const tracks = result.timedtexttracks;
  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] = subs;

  // add menu when it's not there
  if(document.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;
    document.body.appendChild(ol);
    ol.querySelector('.download').addEventListener('click', downloadThis);
    //ol.querySelector('.download-all').addEventListener('click', downloadAll);
    ol.querySelector('.ep-title-in-filename').addEventListener('click', toggleEpTitleInFilename);
    ol.querySelector('.force-all-lang').addEventListener('click', toggleForceLang);
    ol.querySelector('.lang-setting').addEventListener('click', setLangToDownload);
    ol.querySelector('.sub-format').addEventListener('click', setSubFormat);
    setEpTitleInFilename();
    setForceText();
    setLangsText();
    setFormatText();
  }

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

const processMetadata = data => {
  const result = data.video;
  const {type, title} = result;
  if(type === 'show') {
    for(const season of result.seasons) {
      for(const episode of season.episodes) {
        titleCache[episode.id] = {
          type, title,
          season: season.seq,
          episode: episode.seq,
          subtitle: episode.title,
          hiddenNumber: episode.hiddenEpisodeNumbers
        };
      }
    }
  }
  else if(type === 'movie' || type === 'supplemental') {
    titleCache[result.id] = {type, title};
  }
  else {
  	console.debug('[Netflix Subtitle Downloader] unknown video type:', type, result)
  }
};

const getXFromCache = (cache, name) => {
  const id = window.location.pathname.split('/').pop();
  if(cache.hasOwnProperty(id))
    return cache[id];

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

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

  alert("Couldn't find the " + name + ". Wait until the player is loaded. If that doesn't help refresh the page.");
  throw '';
};

const getSubsFromCache = () => getXFromCache(subCache, 'subs');

const pad = (number, letter) => `${letter}${number.toString().padStart(2, '0')}`;

const getTitleFromCache = () => {
  const title = getXFromCache(titleCache, 'title');
  const titleParts = [title.title];
  if(title.type === 'show') {
    const season = pad(title.season, 'S');
    if(title.hiddenNumber) {
      titleParts.push(season);
      titleParts.push(title.subtitle);
    }
    else {
      titleParts.push(season + pad(title.episode, 'E'));
      if(epTitleInFilename)
        titleParts.push(title.subtitle);
    }
  }
  return titleParts.join('.').trim().replace(/[:*?"<>|\\\/]+/g, '_').replace(/ /g, '.');
};

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 subs = getSubsFromCache();
  const title = getTitleFromCache();
  const downloaded = [];

  let filteredLangs;
  if(langs === '')
    filteredLangs = Object.keys(subs);
  else {
    const regularExpression = new RegExp(
      '^(' + langs
        .replace(/\[/g, '\\[')
        .replace(/\]/g, '\\]')
        .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;
  }

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

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

  return [title, stop];
};

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

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

const processMessage = e => {
  const {type, data} = e.detail;
  if(type === 'subs')
    processSubInfo(data);
  else if(type === 'id_override')
    idOverrides[data[0]] = data[1];
  else if(type === 'metadata')
    processMetadata(data);
}

const injection = () => {
  const WEBVTT = 'webvtt-lssdh-ios8';
  const MANIFEST_PATTERN = new RegExp('manifest|licensedManifest');
  const forceSubs = localStorage.getItem('NSD_force-all-lang') !== 'false';

  // hijack JSON.parse and JSON.stringify functions
  ((parse, stringify, open) => {
    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: {type: 'subs', data: data.result}}));
      }
      return data;
    };

    JSON.stringify = function (data) {
      /*{
        let text = stringify(data);
        if (text.includes('dfxp-ls-sdh'))
          console.log(text, data);
      }*/

      if (data && typeof data.url === 'string' && data.url.search(MANIFEST_PATTERN) > -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: {type: 'id_override', data: [videoId, data.movieId]}}));
        }
        catch(ignore) {}
      }
      return stringify(data);
    };

    XMLHttpRequest.prototype.open = function() {
      if(arguments[1] && arguments[1].includes('/metadata?'))
        this.addEventListener('load', () => {
          window.dispatchEvent(new CustomEvent('netflix_sub_downloader_data', {detail: {type: 'metadata', data: this.response}}));
        }, false);
      open.apply(this, arguments);
    };
  })(JSON.parse, JSON.stringify, XMLHttpRequest.prototype.open);
}

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);

const observer = new MutationObserver(function(mutations) {
  mutations.forEach(function(mutation) {
    mutation.addedNodes.forEach(function(node) {
      // add scrollbar - Netflix doesn't expect you to have this manu languages to choose from...
      try {
        (node.parentNode || node).querySelector('.watch-video--selector-audio-subtitle').parentNode.style.overflowY = 'scroll';
      }
      catch(ignore) {}
    });
  });
});
observer.observe(document.body, { childList: true, subtree: true });