YouTube Permanent ProgressBar

Keeps YouTube progress bar visible all the time.

您需要先安裝使用者腳本管理器擴展,如 TampermonkeyGreasemonkeyViolentmonkey 之後才能安裝該腳本。

You will need to install an extension such as Tampermonkey to install this script.

您需要先安裝使用者腳本管理器擴充功能,如 TampermonkeyViolentmonkey 後才能安裝該腳本。

您需要先安裝使用者腳本管理器擴充功能,如 TampermonkeyUserscripts 後才能安裝該腳本。

你需要先安裝一款使用者腳本管理器擴展,比如 Tampermonkey,才能安裝此腳本

您需要先安裝使用者腳本管理器擴充功能後才能安裝該腳本。

(我已經安裝了使用者腳本管理器,讓我安裝!)

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

(我已經安裝了使用者樣式管理器,讓我安裝!)

// ==UserScript==
// @name         YouTube Permanent ProgressBar
// @namespace    http://tampermonkey.net/
// @version      0.4.1
// @description  Keeps YouTube progress bar visible all the time.
// @author       ChromiaCat
// @match        *://www.youtube.com/*
// @run-at      document-idle
// @license      MIT
// ==/UserScript==

(function() {
    "use strict";

    var style = document.createElement('style');
    var to = { createHTML: s => s },
        tp = window.trustedTypes?.createPolicy ? trustedTypes.createPolicy("", to) : to,
        html = s => tp.createHTML(s)
    style.type = 'text/css';
    style.innerHTML = html(
        '.ytp-autohide .ytp-chrome-bottom{opacity:1!important;display:block!important}' +
        '.ytp-autohide .ytp-chrome-bottom .ytp-progress-bar-container{bottom:-1px!important}' +
        '.ytp-autohide .ytp-chrome-bottom .ytp-chrome-controls{opacity:0!important}' +
        '.ytp-progress-bar-container:not(:hover) .ytp-scrubber-container{display:none!important}'
    );
    document.getElementsByTagName('head')[0].appendChild(style);

    var permanentProgressBar = {
        options: {
            UPDATE_VIDEO_TIMER: true,
            UPDATE_PROGRESSBAR: true,
            UPDATE_BUFFERBAR: true,
            TARGET_FPS: 15, // frame per second. Set 0 to update on each requestAnimationFrame call.
        },

        // cache frequently accessed DOM nodes and chapter metrics
        domCache: {player:null, video:null, currentTimeEl:null, progressBar:null, bufferBar:null},
        chapterCache: {len:0,widths:[],totalWidth:0,ratio:1,duration:0},

        // Converts current video time to a human-readable format.
        prettifyVideoTime: function(video) {
            let seconds = "" + Math.floor(video.currentTime % 60);
            let minutes = "" + Math.floor((video.currentTime % 3600) / 60);
            let hours = "" + Math.floor(video.currentTime / 3600);
            if (video.currentTime / 60 > 60) {
                return `${hours}:${minutes.padStart(2, '0')}:${seconds.padStart(2, '0')}`;
            } else {
                return `${minutes}:${seconds.padStart(2, '0')}`;
            }
        },

        // For progress mode, return current time; for buffer mode, return the end of the buffered range that contains currentTime.
        getDuration: function(video, type) {
            if (type === "PROGRESSBAR") {
                return video.currentTime;
            } else if (type === "BUFFERBAR") {
                if (video.buffered.length > 0) {
                    for (let i = 0; i < video.buffered.length; i++) {
                        if (video.currentTime >= video.buffered.start(i) && video.currentTime <= video.buffered.end(i)) {
                            return video.buffered.end(i);
                        }
                    }
                }
                return 0;
            }
        },

        // Updates the current time display on the player.
        updateCurrentTimeField: function(player) {
            const video = this.domCache.video || (this.domCache.video = player.querySelector("video"));
            const currentTimeEl = this.domCache.currentTimeEl || (this.domCache.currentTimeEl = player.querySelector(".ytp-time-current"));
            if (!video || !currentTimeEl) return;
            currentTimeEl.innerText = permanentProgressBar.prettifyVideoTime(video);
        },

        // For non-chaptered videos, update the progress and buffer bars directly.
        updateOverallProgressBar: function(player) {
            const video = this.domCache.video || (this.domCache.video = player.querySelector("video"));
            const progressBar = this.domCache.progressBar || (this.domCache.progressBar = player.querySelector(".ytp-play-progress"));
            const bufferBar = this.domCache.bufferBar || (this.domCache.bufferBar = player.querySelector(".ytp-load-progress"));
            if (!video || !progressBar || !bufferBar) return;
            if (!video.duration) return;

            let progressRatio = video.currentTime / video.duration;
            let bufferRatio = this.getDuration(video, "BUFFERBAR") / video.duration;

            progressBar.style.transform = `scaleX(${Math.min(1, progressRatio.toFixed(5))})`;
            bufferBar.style.transform = `scaleX(${Math.min(1, bufferRatio.toFixed(5))})`;
        },

        // For chaptered videos, update each chapter element directly based on current time.
        updateProgressBarWithChapters: function(player, type) {
            const video = player.querySelector("video");
            if (!video || isNaN(video.duration)) return;

            // Get the chapter elements and corresponding progress elements.
            const chapterElements = player.getElementsByClassName("ytp-progress-bar-padding");
            let chapterProgressEls;
            if (type === "PROGRESSBAR") {
                chapterProgressEls = player.getElementsByClassName("ytp-play-progress");
            } else if (type === "BUFFERBAR") {
                chapterProgressEls = player.getElementsByClassName("ytp-load-progress");
            }
            if (!chapterElements || !chapterProgressEls) return;

            // Compute chapter metrics only if cache is invalid (length/width) OR the video duration has changed.
            // This handles YouTube SPA navigation where a new video may have the same number of chapters but different length.
            if (this.chapterCache.len !== chapterElements.length || !this.chapterCache.totalWidth || this.chapterCache.duration !== video.duration) {
                this.chapterCache.len = chapterElements.length;
                this.chapterCache.widths = Array.from(chapterElements).map(el => el.offsetWidth || el.getBoundingClientRect().width || 0);
                this.chapterCache.totalWidth = this.chapterCache.widths.reduce((a,b)=>a+b,0);
                this.chapterCache.duration = video.duration;

                this.chapterCache.ratio = this.chapterCache.totalWidth ? (video.duration / this.chapterCache.totalWidth) : 1;
            }
            const widths = this.chapterCache.widths;
            const durationWidthRatio = this.chapterCache.ratio;

            let accumulatedWidth = 0;
            for (let i = 0; i < chapterElements.length; i++) {
                const chapterWidth = widths[i];
                const chapterEndTime = durationWidthRatio * (accumulatedWidth + chapterWidth);
                const chapterStartTime = durationWidthRatio * accumulatedWidth;
                let currentTimeForType = this.getDuration(video, type);
                let ratio;
                if (currentTimeForType >= chapterEndTime) {
                    ratio = 1;
                } else if (currentTimeForType < chapterStartTime) {
                    ratio = 0;
                } else {
                    ratio = (currentTimeForType - chapterStartTime) / (chapterEndTime - chapterStartTime);
                }
                chapterProgressEls[i].style.transform = `scaleX(${Math.min(1, ratio.toFixed(5))})`;
                accumulatedWidth += chapterWidth;
            }
        },

        // -------- Cache helpers --------
        resetChapterCache: function(){
            this.chapterCache = {len:0,widths:[],totalWidth:0,ratio:1,duration:0};
            this.domCache = {player:null, video:null, currentTimeEl:null, progressBar:null, bufferBar:null};
        },

        // The main update function which selects chapter-mode or overall mode.
        update: function() {
            const player = document.querySelector(".html5-video-player");
            if (!player) return;

            if (this.options.UPDATE_VIDEO_TIMER) {
                this.updateCurrentTimeField(player);
            }

            // If chapter elements exist, update chapter-mode; otherwise use overall mode.
            let chapterElements = player.getElementsByClassName("ytp-progress-bar-padding");
            if (chapterElements.length > 0) {
                if (this.options.UPDATE_PROGRESSBAR) {
                    this.updateProgressBarWithChapters(player, "PROGRESSBAR");
                }
                if (this.options.UPDATE_BUFFERBAR) {
                    this.updateProgressBarWithChapters(player, "BUFFERBAR");
                }
            } else {
                this.updateOverallProgressBar(player);
            }
        },

        /* ------------------ Performance-friendly update loop ------------------ */
        rafId: 0,
        resizeObserver: null,

        /* Starts a requestAnimationFrame loop only while the <video> is playing. */
        attachLoop: function(video) {
            let last = 0;
            const loop = (ts) => {
                if (video.paused || document.hidden) {
                    this.rafId = requestAnimationFrame(loop);
                    return;
                }
                if (!this.options.TARGET_FPS || ts - last >= 1000 / this.options.TARGET_FPS) {
                    this.update();
                    last = ts;
                }
                this.rafId = requestAnimationFrame(loop);
            };
            this.rafId = requestAnimationFrame(loop);
        },

        /* Locate the player & video element and wire play/pause events. */
        waitForVideo: function() {
            const tryAttach = () => {
                const player = this.domCache.player = document.querySelector('.html5-video-player');
                const video  = this.domCache.video = player?.querySelector('video');
                if (!video) {
                    setTimeout(tryAttach, 1000);
                    return;
                }

                // Observe layout changes to invalidate chapter width cache (helps embeds/resizes)
                try {
                    if (this.resizeObserver) this.resizeObserver.disconnect();
                    const ro = new ResizeObserver(() => { this.chapterCache.totalWidth = 0; });
                    this.resizeObserver = ro;
                    const observedEl = player.querySelector('.ytp-progress-bar') || player;
                    ro.observe(observedEl);
                } catch(e) { /* ResizeObserver may be unavailable */ }

                const startLoop = () => {
                    cancelAnimationFrame(this.rafId);
                    this.attachLoop(video);
                };
                const stopLoop = () => cancelAnimationFrame(this.rafId);

                video.addEventListener('play',   startLoop);
                video.addEventListener('playing',startLoop);
                video.addEventListener('pause',  stopLoop);
                video.addEventListener('ended',  stopLoop);

                // Auto-start if video already playing
                if (!video.paused) startLoop();
            };
            tryAttach();
        },

        start: function() {
            const onNavigate = () => {
                this.resetChapterCache();
                this.waitForVideo();
            };
            document.addEventListener('yt-navigate-finish', onNavigate);
            this.waitForVideo();
        }
    };

    permanentProgressBar.start();
})();