YouTube Live CPU Tamer

It reduces the high CPU usage on Super Chats with nothing to lose.

Versione datata 11/05/2020. Vedi la nuova versione l'ultima versione.

Dovrai installare un'estensione come Tampermonkey, Greasemonkey o Violentmonkey per installare questo script.

Dovrai installare un'estensione come Tampermonkey o Violentmonkey per installare questo script.

Dovrai installare un'estensione come Tampermonkey o Violentmonkey per installare questo script.

Dovrai installare un'estensione come Tampermonkey o Userscripts per installare questo script.

Dovrai installare un'estensione come ad esempio Tampermonkey per installare questo script.

Dovrai installare un gestore di script utente per installare questo script.

(Ho già un gestore di script utente, lasciamelo installare!)

Dovrai installare un'estensione come ad esempio Stylus per installare questo stile.

Dovrai installare un'estensione come ad esempio Stylus per installare questo stile.

Dovrai installare un'estensione come ad esempio Stylus per installare questo stile.

Dovrai installare un'estensione per la gestione degli stili utente per installare questo stile.

Dovrai installare un'estensione per la gestione degli stili utente per installare questo stile.

Dovrai installare un'estensione per la gestione degli stili utente per installare questo stile.

(Ho già un gestore di stile utente, lasciamelo installare!)

// ==UserScript==
// @name        YouTube Live CPU Tamer
// @name:ja     YouTube Live CPU Tamer
// @name:zh-CN  YouTube Live CPU Tamer
// @description It reduces the high CPU usage on Super Chats with nothing to lose.
// @description:ja スーパーチャットによる高いCPU使用率を削減します。見た目は何も変わりません。
// @description:zh-CN 降低超级聊天的高CPU利用率。外观完全没有变化。
// @namespace   knoa.jp
// @include     https://www.youtube.com/live_chat*
// @include     https://www.youtube.com/live_chat_replay*
// @version     2.0.4
// @grant       none
// ==/UserScript==

(function(){
  const SCRIPTID = 'YouTubeLiveCpuTamer';
  const SCRIPTNAME = 'YouTube Live CPU Tamer';
  const DEBUG = false;/*
[update] 2.0.4
Added "remove tickers" button for further CPU usage reduction. + minor fix.

[bug]

[todo]

[possible]

[research]
放送開始前の待機画面でもHelper(GPU)が食ってる件
リアルタイム視聴時のほうがHelper(GPU)が消費する件は新着確認js処理のせいか

[memo]
  */
  if(console.time) console.time(SCRIPTID);
  const MS = 1, SECOND = 1000*MS, MINUTE = 60*SECOND, HOUR = 60*MINUTE, DAY = 24*HOUR, WEEK = 7*DAY, MONTH = 30*DAY, YEAR = 365*DAY;
  const THROTTLE = 1000*MS;
  const site = {
    targets: {
      itemsNode: () => $('yt-live-chat-ticker-renderer #items'),
    },
    get: {
      tickerItemInsideContainers: (items) => items.querySelectorAll('yt-live-chat-ticker-paid-message-item-renderer #container'),/* existing items */
      tickerItemInsideContainer: (node) => node.querySelector('yt-live-chat-ticker-paid-message-item-renderer #container'),/* for observer */
    },
  };
  let elements = {};
  const core = {
    initialize: function(){
      elements.html = document.documentElement;
      elements.html.classList.add(SCRIPTID);
      text.setup(texts, top.document.documentElement.lang);
      core.ready();
      core.addStyle('style');
    },
    ready: function(){
      core.getTargets(site.targets).then(() => {
        log("I'm ready.");
        core.observeTickerItems();
        core.prepareRemoveTickersButton();
      });
    },
    observeTickerItems: function(){
      let containers = site.get.tickerItemInsideContainers(elements.itemsNode);
      Array.from(containers).forEach(container => {
        core.observeTickerItemInsideContainer(container);
      });
      observe(elements.itemsNode, function(records){
        records.forEach(r => r.addedNodes.forEach(node => {
          let container = site.get.tickerItemInsideContainer(node);
          if(container) core.observeTickerItemInsideContainer(container);
        }));
      });
    },
    observeTickerItemInsideContainer: function(container){
      container.parentNode.style.background = container.style.background;
      let lastUpdated = Date.now();
      observe(container, function(records){
        let now = Date.now();
        if(now - lastUpdated < THROTTLE) return;
        lastUpdated = now;
        container.parentNode.style.background = container.style.background;
      }, {attributes: true, attributeFilter: ['style']});
    },
    prepareRemoveTickersButton: function(){
      let button = createElement(html.removeTickersButton());
      button.addEventListener('click', function(e){
        elements.itemsNode.parentNode.removeChild(elements.itemsNode);
      });
      elements.itemsNode.parentNode.appendChild(button);
    },
    getTarget: function(selector, retry = 10){
      const key = selector.name;
      const get = function(resolve, reject, retry){
        let selected = selector();
        if(selected && selected.length > 0) selected.forEach((s) => s.dataset.selector = key);/* elements */
        else if(selected instanceof HTMLElement) selected.dataset.selector = key;/* element */
        else if(--retry) return log(`Not found: ${key}, retrying... (${retry})`), setTimeout(get, 1000, resolve, reject, retry);
        else return reject(selector);
        elements[key] = selected;
        resolve(selected);
      };
      return new Promise(function(resolve, reject){
        get(resolve, reject, retry);
      }).catch(selector => {
        log(`Not found: ${key}, I give up.`);
      });
    },
    getTargets: function(selectors, retry = 10){
      return Promise.all(Object.values(selectors).map(selector => core.getTarget(selector, retry)));
    },
    addStyle: function(name = 'style'){
      if(html[name] === undefined) return;
      let style = createElement(html[name]());
      document.head.appendChild(style);
      if(elements[name] && elements[name].isConnected) document.head.removeChild(elements[name]);
      elements[name] = style;
    },
  };
  const texts = {
    'remove tickers by ${SCRIPTNAME}': {
      en: () => `remove tickers by ${SCRIPTNAME}`,
      ja: () => `履歴欄を削除 by ${SCRIPTNAME}`,
      zh: () => `删除历史记录栏 by ${SCRIPTNAME}`,
    },
  };
  const html = {
    removeTickersButton: () => `<button id="${SCRIPTID}-removeTickers" title="${text('remove tickers by ${SCRIPTNAME}')}">╳</button>`,
    style: () => `
      <style type="text/css">
        yt-live-chat-ticker-renderer #items > *{
          border-radius: 999px;
        }
        yt-live-chat-ticker-renderer #items > * > #container{
          background: none !important;
        }
        yt-live-chat-ticker-renderer #${SCRIPTID}-removeTickers{
          cursor: pointer;
          position: absolute;
          top: 50%;
          left: 5px;
          transform: translateY(-50%);
          border-radius: 100vmax;
          background: white;
          filter: drop-shadow(0px 0px 1px rgba(0,0,0,.25));
          height: 20px;
          width: 20px;
          padding: 0 !important;
          opacity: 0;
          transition: opacity 250ms;
          pointer-events: none;
        }
        yt-live-chat-ticker-renderer:hover #left-arrow-container[hidden] ~ #${SCRIPTID}-removeTickers{
          opacity: 1;
          pointer-events: auto;
        }
        yt-live-chat-ticker-renderer #items > *{
          transition: transform 250ms;
        }
        yt-live-chat-ticker-renderer:hover #items > *{
          transform: translateX(5px);
        }
      </style>
    `,
  };
  const text = function(key, ...args){
    if(text.texts[key] === undefined){
      log('Not found text key:', key);
      return key;
    }else return text.texts[key](args);
  };
  text.setup = function(texts, language){
    let languages = [...window.navigator.languages];
    if(language) languages.unshift(...String(language).split('-').map((p,i,a) => a.slice(0,1+i).join('-')).reverse());
    if(!languages.includes('en')) languages.push('en');
    languages = languages.map(l => l.toLowerCase());
    Object.keys(texts).forEach(key => {
      Object.keys(texts[key]).forEach(l => texts[key][l.toLowerCase()] = texts[key][l]);
      texts[key] = texts[key][languages.find(l => texts[key][l] !== undefined)] || (() => key);
    });
    text.texts = texts;
  };
  const $ = function(s, f){
    let target = document.querySelector(s);
    if(target === null) return null;
    return f ? f(target) : target;
  };
  const $$ = function(s, f){
    let targets = document.querySelectorAll(s);
    return f ? Array.from(targets).map(t => f(t)) : targets;
  };
  const createElement = function(html = '<span></span>'){
    let outer = document.createElement('div');
    outer.innerHTML = html;
    return outer.firstElementChild;
  };
  const observe = function(element, callback, options = {childList: true, attributes: false, characterData: false, subtree: false}){
    let observer = new MutationObserver(callback.bind(element));
    observer.observe(element, options);
    return observer;
  };
  const log = function(){
    if(!DEBUG) return;
    let l = log.last = log.now || new Date(), n = log.now = new Date();
    let error = new Error(), line = log.format.getLine(error), callers = log.format.getCallers(error);
    //console.log(error.stack);
    console.log(
      SCRIPTID + ':',
      /* 00:00:00.000  */ n.toLocaleTimeString() + '.' + n.getTime().toString().slice(-3),
      /* +0.000s       */ '+' + ((n-l)/1000).toFixed(3) + 's',
      /* :00           */ ':' + line,
      /* caller.caller */ (callers[2] ? callers[2] + '() => ' : '') +
      /* caller        */ (callers[1] || '') + '()',
      ...arguments
    );
  };
  log.formats = [{
      name: 'Firefox Scratchpad',
      detector: /MARKER@Scratchpad/,
      getLine: (e) => e.stack.split('\n')[1].match(/([0-9]+):[0-9]+$/)[1],
      getCallers: (e) => e.stack.match(/^[^@]*(?=@)/gm),
    }, {
      name: 'Firefox Console',
      detector: /MARKER@debugger/,
      getLine: (e) => e.stack.split('\n')[1].match(/([0-9]+):[0-9]+$/)[1],
      getCallers: (e) => e.stack.match(/^[^@]*(?=@)/gm),
    }, {
      name: 'Firefox Greasemonkey 3',
      detector: /\/gm_scripts\//,
      getLine: (e) => e.stack.split('\n')[1].match(/([0-9]+):[0-9]+$/)[1],
      getCallers: (e) => e.stack.match(/^[^@]*(?=@)/gm),
    }, {
      name: 'Firefox Greasemonkey 4+',
      detector: /MARKER@user-script:/,
      getLine: (e) => e.stack.split('\n')[1].match(/([0-9]+):[0-9]+$/)[1] - 500,
      getCallers: (e) => e.stack.match(/^[^@]*(?=@)/gm),
    }, {
      name: 'Firefox Tampermonkey',
      detector: /MARKER@moz-extension:/,
      getLine: (e) => e.stack.split('\n')[1].match(/([0-9]+):[0-9]+$/)[1] - 6,
      getCallers: (e) => e.stack.match(/^[^@]*(?=@)/gm),
    }, {
      name: 'Chrome Console',
      detector: /at MARKER \(<anonymous>/,
      getLine: (e) => e.stack.split('\n')[2].match(/([0-9]+):[0-9]+\)?$/)[1],
      getCallers: (e) => e.stack.match(/[^ ]+(?= \(<anonymous>)/gm),
    }, {
      name: 'Chrome Tampermonkey',
      detector: /at MARKER \(chrome-extension:.*?\/userscript.html\?id=/,
      getLine: (e) => e.stack.split('\n')[2].match(/([0-9]+):[0-9]+\)?$/)[1] - 5,
      getCallers: (e) => e.stack.match(/[^ ]+(?= \(chrome-extension:)/gm),
    }, {
      name: 'Chrome Extension',
      detector: /at MARKER \(chrome-extension:/,
      getLine: (e) => e.stack.split('\n')[2].match(/([0-9]+):[0-9]+\)?$/)[1],
      getCallers: (e) => e.stack.match(/[^ ]+(?= \(chrome-extension:)/gm),
    }, {
      name: 'Edge Console',
      detector: /at MARKER \(eval/,
      getLine: (e) => e.stack.split('\n')[2].match(/([0-9]+):[0-9]+\)$/)[1],
      getCallers: (e) => e.stack.match(/[^ ]+(?= \(eval)/gm),
    }, {
      name: 'Edge Tampermonkey',
      detector: /at MARKER \(Function/,
      getLine: (e) => e.stack.split('\n')[2].match(/([0-9]+):[0-9]+\)$/)[1] - 4,
      getCallers: (e) => e.stack.match(/[^ ]+(?= \(Function)/gm),
    }, {
      name: 'Safari',
      detector: /^MARKER$/m,
      getLine: (e) => 0,/*e.lineが用意されているが最終呼び出し位置のみ*/
      getCallers: (e) => e.stack.split('\n'),
    }, {
      name: 'Default',
      detector: /./,
      getLine: (e) => 0,
      getCallers: (e) => [],
    }];
  log.format = log.formats.find(function MARKER(f){
    if(!f.detector.test(new Error().stack)) return false;
    //console.log('////', f.name, 'wants', 0/*line*/, '\n' + new Error().stack);
    return true;
  });
  core.initialize();
  if(console.timeEnd) console.timeEnd(SCRIPTID);
})();