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Youtube HD Premium

Automcatically switches to your pre-selected resolution. Enables premium when possible.

// ==UserScript==
// @name          Youtube HD Premium
// @icon          data:image/png;base64,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
// @author        ElectroKnight22
// @namespace     electroknight22_youtube_hd_namespace
// @version       2024.07.06.2
// @match         *://www.youtube.com/*
// @exclude       *://www.youtube.com/live_chat*
// @grant         GM.getValue
// @grant         GM.setValue
// @grant         GM_registerMenuCommand
// @grant         GM_unregisterMenuCommand
// @license       MIT
// @description      Automcatically switches to your pre-selected resolution. Enables premium when possible.
// @description:zh-TW   自動切換到你預先設定的畫質。會優先使用Premium位元率。
// @description:zh-CN   自动切换到你预先设定的画质。会优先使用Premium比特率。
// @description:ja      自動的に設定した画質に替わります。Premiumのビットレートを優先的に選択します。

// ==/UserScript==

/*jshint esversion: 11 */

(function() {
    "use strict";

    const DEFAULT_SETTINGS = {
        targetResolution: "hd2160"
    };

    const DEBUG = false;
    const resolutions = ['highres', 'hd2880', 'hd2160', 'hd1440', 'hd1080', 'hd720', 'large', 'medium', 'small', 'tiny', 'auto'];
    const quality = {
        highres: 4320,
        hd2880:  2880,
        hd2160:  2160,
        hd1440:  1440,
        hd1080:  1080,
        hd720:   720,
        large:   480,
        medium:  360,
        small:   240,
        tiny:    144,
        auto:    0
    };

    const qualityLevels = Object.fromEntries(
        Object.entries(quality).map(([key, value]) => [value, key])
    );

    let userSettings = { ...DEFAULT_SETTINGS };
    let menuCommandIds = [];

    let doc = document, win = window;
    let vidId = null;

    // --------------------
    // --- FUNCTIONS ------
    // --------------------

    function debugLog(message, shouldShow = true) {
        if (DEBUG && shouldShow) {
            console.log("YTHD DEBUG | " + message);
        }
    }

    // --------------------
    // Attempt to set the video resolution to target quality or the next best quality
    function setResolution(target, force = false) {
        if (target == 'auto') return;

        let ytPlayer = doc.getElementById("movie_player") || doc.getElementsByClassName("html5-video-player")[0];

        if (!isValidVideo(ytPlayer, force)) return;

        vidId = ytPlayer.getVideoData().video_id;

        let localItem = null;
        try {
            localStorage.getItem("yt-player-quality");
        } catch {
            debugLog("Fetching last used quality failed catastrophically. Likely the website is not YouTube. If website is YouTube then YouTube changed something.");
        }

        let limitList = ytPlayer.getAvailableQualityLevels();
        let limit = limitList[0];
        if (quality[target] > quality[limit]) {
            target = limit;
        }

        let premiumIndicator = "Premium";
        let premiumData = ytPlayer.getAvailableQualityData().find(q => q.quality == target && q.qualityLabel.includes(premiumIndicator) && q.isPlayable);
        ytPlayer.setPlaybackQualityRange(target, target, premiumData?.formatId);
        debugLog("Set quality to: " + target + (premiumData ? " Premium" : ""));

        if (localItem){
            localStorage.setItem("yt-player-quality",localItem);
        }
        else {
            localStorage.removeItem("yt-player-quality");
        }
    }

    function isValidVideo(ytPlayer, force) {
        if (!ytPlayer?.getAvailableQualityLabels()[0]) {
            debugLog("Video data missing");
            return false;
        }

        if (vidId == ytPlayer.getVideoData().video_id && !force) {
            debugLog("Duplicate load");
            return false;
        }

        return true;
    }

    // --------------------
    // Functions for the quality selection menu

    function createQualityMenu() {
        const menu_command_id_0 = GM_registerMenuCommand("Set Preferred Quality (show/hide)", function(MouseEvent) {
            menuCommandIds[0] ? removeQualityMenuItems() : showQualityMenuItems();
        }, {
            autoClose: false
        });
    }

    function showQualityMenuItems() {
        removeQualityMenuItems();
        resolutions.forEach((resolution) => {
            let qualityText = (resolution === 'auto') ? 'auto' : quality[resolution] + "p";
            if (resolution === userSettings.targetResolution) {
                qualityText += " (selected)";
            }
            let menuCommandId = GM_registerMenuCommand(qualityText, function() {
                setSelectedResolution(resolution);
            }, {
                autoClose: false,
            });
            menuCommandIds.push(menuCommandId);
        });
    }

    function removeQualityMenuItems() {
        menuCommandIds.forEach((menuCommandId) => {
            GM_unregisterMenuCommand(menuCommandId);
        });
        menuCommandIds = [];
    }

    function setSelectedResolution(resolution) {
        if (userSettings.targetResolution == resolution) return;
        userSettings.targetResolution = resolution;
        GM.setValue('targetResolution', resolution);
        removeQualityMenuItems();
        showQualityMenuItems();
        debugLog(resolution);
        setResolution(resolution, true);
    }

    // --------------------
    // Sync settings with locally storaged values
    async function applySettings() {
        try {
            if (typeof GM != 'undefined' && GM.getValue && GM.setValue && GM.deleteValue && GM.listValues) {
                // Get all keys from GM
                const gmKeys = await GM.listValues();

                // Write any missing key-value pairs from DEFAULT_SETTINGS to GM
                await Promise.all(Object.entries(DEFAULT_SETTINGS).map(async ([k, v]) => {
                    if (!gmKeys.includes(k)) {
                        await GM.setValue(k, v);
                    }
                }));

                // Delete any extra keys in GM that are not in DEFAULT_SETTINGS
                await Promise.all(gmKeys.map(async key => {
                    if (!(key in DEFAULT_SETTINGS)) {
                        await GM.deleteValue(key);
                    }
                }));

                // Retrieve and update user settings from GM
                await Promise.all(
                    gmKeys.map(k => GM.getValue(k).then(v => [k, v]))
                ).then(c => c.forEach(([nk, nv]) => {
                    userSettings[nk] = nv;
                }));

                debugLog(Object.entries(userSettings).map(([k, v]) => k + ": " + v).join(", "));
            }
        } catch (error) {
            debugLog("Error in applySettings: " + error.message);
        }
    }

    // --------------------
    // Main function
    function main() {
        createQualityMenu();
        setResolution(userSettings.targetResolution);
        win.addEventListener("loadstart", () => { setResolution(userSettings.targetResolution); }, true);
    }

    // --------------------
    // Entry Point
    applySettings().then(main);
})();