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Stick YouTube Progress Bar

Stick YouTube video progress bar to the player bottom

当前为 2023-11-18 提交的版本，查看 最新版本。

// ==UserScript==
// @name          Stick YouTube Progress Bar
// @version       1.0.8
// @match         https://www.youtube.com/**
// @author        peng-devs
// @namespace     https://greasyfork.org/users/57176
// @description   Stick YouTube video progress bar to the player bottom
// @icon          https://www.youtube.com/s/desktop/c1d331ff/img/favicon_48x48.png
// @grant         none
// @allFrames     true
// @license       MIT
// ==/UserScript==

(function() {
  'use strict';

  const NAME = "Stick YouTube Progress Bar";
  const UPDATE_INTERVAL = 500;
  const SMOOTH_ANIMATION = false;

  let INTERVAL;
  function main() {
    if (!location.pathname.startsWith('/watch') &&
       !location.pathname.startsWith('/live'))
      return

    if (INTERVAL) {
      INTERVAL = undefined;
    }

    const observer = new MutationObserver((_) => {
      const progress = document.getElementById('stick_progress');

      // 如果是直播的話就不用了
      const live_badge = document.querySelector(".ytp-live-badge");
      if (live_badge && getComputedStyle(live_badge).display !== 'none') {
        // TODO: 或許不用砍掉，可以直接用 css 的方式把它藏起來就好了？
        progress?.remove();
        observer.disconnect();
        console.log(`[${NAME}] cancaled in livestream`);
        return;
      }

      // 已經建好的可以重複利用
      if (progress) return

      // 判斷 youtube player 初始化完了沒
      const intitailized = document.querySelector("video.video-stream");
      if (!intitailized) return;

      console.log(`[${NAME}] initializing...`);

      INTERVAL = stick_progress_bar();

      observer.disconnect();
      console.log(`[${NAME}] loaded`);
    });
    observer.observe(document.body, { childList: true, subtree: true });
  }

  function stick_progress_bar() {
    inject_custom_style(`

      #stick_progress {
        display: none;
        z-index: 32;
        position: absolute;
        bottom: 4px;
        width: 97.5%;
        height: 4px;
        margin: 0 1.25%;
        background-color: rgba(255, 255, 255, .2);
      }

      .stick_play_progress, .stick_load_progress {
        position: absolute;
        width: 100%;
        height: 100%;
      }

      .stick_play_progress, .stick_load_progress {
        transform-origin: left;
        ${SMOOTH_ANIMATION ? `transition: all ${UPDATE_INTERVAL - 50}ms linear;` : ''}
        transform: scaleX(0);
      }

      .stick_load_progress {
        z-index: 33;
        background-color: rgba(255, 255, 255, .4);
      }

      .stick_play_progress {
        z-index: 34;
        background-color: #f00;
      }

      .ytp-autohide #stick_progress {
        display: block;
      }
    `);

    const progress = document.createElement("div");
    progress.id = "stick_progress";

    const play_progress = document.createElement("div");
    play_progress.className = "stick_play_progress";
    progress.append(play_progress);

    const load_progress = document.createElement("div");
    load_progress.className = "stick_load_progress";
    progress.append(load_progress);

    const player = document.querySelector("#movie_player");
    player.append(progress);

    const video = document.querySelector("video.video-stream");
    const interval = setInterval(() => {
      // 只有在自動隱藏的時候才去更新進度條，不想浪費資源
      if (!player.classList.contains("ytp-autohide")) return;

      const progress = video.currentTime / video.duration;
      play_progress.style.transform = `scaleX(${progress})`;

      const loaded_progress = video.buffered.end(0) / video.duration;
      load_progress.style.transform = `scaleX(${loaded_progress})`;
    }, UPDATE_INTERVAL);

    return interval;
  }

  function inject_custom_style(css) {
    const style = document.createElement("style");
    document.head.append(style);
    style.dataset.source = NAME;
    style.innerHTML = css;
  }

  main();
  document.addEventListener('yt-navigate-finish', main, true);

})();