Better-Youtube-Plus/src/inject.js

'use strict';


//  ['hd2160', 'hd1440', 'hd1080', 'hd720', 'large', 'medium', 'small', 'tiny', 'auto']
const prefs = {
  hd: true,
  once: false,
  higher: true,
  quality: ["hd1080"],
  log: false,
  highFramerate: true
};


const script = document.createElement('script');
Object.assign(script.dataset, prefs);
script.textContent = `
  window.yttools = window.yttools || [];

  {
      const isTypeSupported = MediaSource.isTypeSupported;
      MediaSource.isTypeSupported = function(videoType) {
          const prefs = resolutionChangeListener.prefs;
          // Block all queries regarding high-framerate support.
          if (prefs.highFramerate === 'false') {
              const matches = videoType.match(/framerate=(\\d+)/);
              if (matches && (matches[1] > 30)) {
                  return false;
              }
          }
          return isTypeSupported(videoType);
      }
  }

  function resolutionChangeListener(e) {
      const prefs = resolutionChangeListener.prefs;
      const player = resolutionChangeListener.player;
      const log = (...args) => prefs.log === 'true' && console.log('Better-Youtube-Plus: ', ...args);

      try {
          if (e === 1 && player) {
              const levels = player.getAvailableQualityLevels();
              if (levels.length === 0) {
                  return log("Returned empty quality levels...");
              }

              //  ['hd2160', 'hd1440', 'hd1080', 'hd720', 'large', 'medium', 'small', 'tiny', 'auto']
              const qualities = player.getAvailableQualityLevels();
              const q = player.getPlaybackQuality();
              // if ((q.startsWith('h') && prefs.quality.startsWith('h')) && prefs.hd === 'true') {
              //     console.log("Quality matches requested resolution...");
              //     return;
              // }

              const compare = (q1, q2) => {
                  if (q2 === 'auto') {
                      return false;
                  }
                  const i1 = qualities.indexOf(q1);
                  const i2 = qualities.indexOf(q2);
                  if (i1 === -1 || i2 === -1) {
                      return false;
                  }
                  return i1 - i2 <= 0;
              };

              if (prefs.higher === 'true' && compare(q, prefs.quality)) {
                  return log('Quality is higher than ' + prefs.quality + '... skipping quality change.');
              }
              if (q === prefs.quality) {
                  return log('Selected quality is okay...');
              }

              const find = increase => {
                  if (prefs.quality === 'highest') {
                      return levels[0];
                  }
                  else {
                      if (increase) {
                          prefs.quality = qualities[qualities.indexOf(prefs.quality) - 1] || levels[0];
                      }
                      const index = levels.indexOf(prefs.quality);
                      if (index !== -1) {
                          return prefs.quality;
                      }
                      return find(true);
                  }
              };

              const nq = find();
              if (q === nq) {
                  return log('Requested quality is unavailable... skipping change.');
              }
              player.setPlaybackQuality(nq);
              try {
                  player.setPlaybackQualityRange(nq, nq);
              }
              catch (e) {}
              if (prefs.once === 'true') {
                  player.removeEventListener('onStateChange', 'resolutionChangeListener');
                  window.resolutionChangeListener = () => {};
                  log("Removing Listener...");
              }

              log('Quality was ' + q + ' and now is set to ' + nq);
          }
      }
      catch (e) {
          log(e);
      }
  }

  resolutionChangeListener.prefs = document.currentScript.dataset;
  window.yttools.push(e => {
      resolutionChangeListener.player = e;
      resolutionChangeListener(1);
      e.addEventListener('onStateChange', resolutionChangeListener);
  });

  function onYouTubePlayerReady(player) {
      if (yttools.resolved !== true) {
          yttools.resolved = true;
          yttools.forEach(c => {
              try {
                  c(player);
              }
              catch (e) {}
          });
      }
  }


  window.addEventListener('spfready', () => {
      if (typeof window.ytplayer === 'object' && window.ytplayer.config && yttools.resolved !== true) {
          window.ytplayer.config.args.jsapicallback = 'onYouTubePlayerReady';
      }
  });

  window.addEventListener('yt-navigate-finish', () => {
      const player = document.querySelector('.html5-video-player');
      if (player && yttools.resolved !== true) {
          yttools.resolved = true;
          yttools.forEach(c => c(player));
      }
  });
`;

document.documentElement.appendChild(script);
script.remove();