YouTubeで自動翻訳字幕（日本語）を常にオン

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YouTubeで自動翻訳字幕（日本語）を常にオン

Bキーで再度試みる
目前为 2019-10-27 提交的版本，查看最新版本。
换行
// ==UserScript==
// @name YouTubeで自動翻訳字幕（日本語）を常にオン
// @description Bキーで再度試みる
// @version      0.1
// @run-at document-idle
// @match *://www.youtube.com/*
// @grant none
// @namespace http://greasyfork.icu/users/181558
// ==/UserScript==

(function() {

  const WAIT_PAGEOPEN = 500; // ミリ秒
  const WAIT_EACHACTION = 500; // ミリ秒
  const ENABLE_EVENJAPANESE = 0; // 日本語タイトルの動画でも実行
  const ENABLE_EVENEMBED = 1; // 埋め込みでも実行

  document.addEventListener('keydown', function(e) {
    if (/input|textarea/i.test(e.target.tagName) == false) {
      var key = (e.shiftKey ? "Shift+" : "") + (e.altKey ? "Alt+" : "") + (e.ctrlKey ? "Ctrl+" : "") + e.key;
      if (key == "b") {
        toJP();
        e.preventDefault();
      }
    }
  }, false);

  var href = location.href;
  var observer = new MutationObserver(function(mutations) {
    if (href !== location.href) {
      href = location.href;
      run(WAIT_PAGEOPEN * 3);
    }
  });
  observer.observe(document, { childList: true, subtree: true });

  if (window == parent) run(WAIT_PAGEOPEN);

  return;

  function run(delay = 500) {
    setTimeout(function() {
      //      console.log("run");
      var title = eleget0('//h1/yt-formatted-string');
      if (!(location.href.match(/\/embed/)) && !title) { setTimeout(() => { run(); }, 250); return; }
      if (!ENABLE_EVENJAPANESE && title && title.innerText.match(/[\u30a0-\u30ff\u3040-\u309f\u3005-\u3006\u30e0-\u9fcf]+/)) return; // タイトルに日本語あるならやめる
      toJP();
    }, delay);
  }

  function toJP() {
    if (!(location.href.match(ENABLE_EVENEMBED ? /:\/\/www\.youtube\.com\/watch\?|:\/\/www\.youtube\.com\/embed/ : /:\/\/www\.youtube\.com\/watch\?/))) return;
    if (eleget0('//button[@class="ytp-subtitles-button ytp-button" and @aria-label="字幕（c）"]')) { // 字幕ボタン
      elecli('//button[@class="ytp-subtitles-button ytp-button" and @aria-label="字幕（c）" and @aria-pressed="false"]', 1); // 字幕ボタン
      elecli('//div[@class="ytp-right-controls"]/button[@aria-label="設定"]', 2); // 設定ボタン
      elecli('//div[1]/div/span[text()="字幕"]', 3, "close");
      elecli('//div[text()="自動翻訳"]', 4, "close");
      elecli('//div[@class="ytp-menuitem-label" and text()="日本語"]', 5, "close");
      elecli('//div[last()]/button[@data-tooltip-target-id="ytp-settings-button" and @aria-expanded="true"]', 7, "blur");
    }
  }

  function elecli(xpath, delay = 0, command = false) {
    setTimeout(() => {
      var ele = eleget0(xpath);
      if (ele) {
        //        console.log("Found:" + ele.outerHTML);
        if (command == "focus") ele.focus();
        else ele.click();
      } else {
        //        console.log("Not found:" + xpath);
        if (command == "close") elecli('//div[last()]/button[@data-tooltip-target-id="ytp-settings-button" and @aria-expanded="true"]');
      }
      if (command == "blur") elecli('//div[@id="movie_player"]|//div[@id="player"]/div/div/video', 0, "focus");
    }, delay * WAIT_EACHACTION)
  }

  function eleget0(xpath, node = document) {
    if (!xpath) return null;
    try {
      var ele = document.evaluate(xpath, node, null, XPathResult.UNORDERED_NODE_SNAPSHOT_TYPE, null);
      return ele.snapshotLength > 0 ? ele.snapshotItem(0) : "";
    } catch (e) { return null; }
  }

})()