// ==UserScript==
// @name         YouTube Plus
// @namespace    https://github.com/haoch1/userscripts
// @version      2.1.1
// @icon         https://www.youtube.com/s/desktop/af0a3c1e/img/favicon_144x144.png
// @icon64       https://www.youtube.com/s/desktop/af0a3c1e/img/favicon_144x144.png
// @description  支持最高画质、详细统计信息与评论中文翻译的自动启用设置，保留统计快捷开关及 MB/s 网速换算
// @downloadURL  https://raw.githubusercontent.com/haoch1/userscripts/main/scripts/youtube-plus.user.js
// @updateURL    https://raw.githubusercontent.com/haoch1/userscripts/main/scripts/youtube-plus.user.js
// @match        https://www.youtube.com/*
// @match        https://youtube.com/*
// @run-at       document-start
// @grant        GM_getValue
// @grant        GM_setValue
// @grant        GM_registerMenuCommand
// @grant        unsafeWindow
// @noframes
// @license      MIT
// ==/UserScript==

(() => {
    'use strict';

    const BUTTON_ID = 'youtube-speed-toggle';
    const SPEED_ID = 'youtube-speed-converted';
    const settings = {
        highestQuality: GM_getValue('highestQuality', true),
        autoStats: GM_getValue('autoStats', true),
        translateComments: GM_getValue('translateComments', true),
    };
    // Icon used by YouTube's "Stats for nerds" context-menu item.
    const ICON_PATH = 'M22 34h4V22h-4v12zm2-30C12.95 4 4 12.95 4 24s8.95 20 20 20 20-8.95 20-20S35.05 4 24 4zm0 36c-8.82 0-16-7.18-16-16S15.18 8 24 8s16 7.18 16 16-7.18 16-16 16zm-2-22h4v-4h-4v4z';
    let button = null;
    let openedStats = null;
    let currentVideo = null;
    const menuIds = {};
    let observedSpeedValue = null;
    const speedObserver = new MutationObserver(updateSpeedDisplay);
    const panelObserver = new MutationObserver(() => {
        if (updateSpeedDisplay()) panelObserver.disconnect();
    });
    const commentRoots = new Set();
    const translationQueue = new Set();
    let translatedComments = new WeakSet();
    let translationFrame = 0;
    let translationTimer = 0;
    let commentsNavigating = false;
    const commentObserver = new MutationObserver(scheduleCommentScan);

    function setSetting(key, enabled) {
        settings[key] = enabled;
        GM_setValue(key, enabled);
        updateMenus();
        if (currentVideo) {
            if (key === 'highestQuality') currentVideo.qualityApplied = false;
            else if (key === 'autoStats') currentVideo.statsApplied = false;
        }
        if (key === 'autoStats' && !enabled && openedStats?.automatic) closeOpenedStats();
        if (key === 'translateComments') resetCommentTranslation();
        sync();
    }

    function updateMenus() {
        const options = [
            ['highestQuality', '自动最高画质'],
            ['autoStats', '自动详细统计信息'],
            ['translateComments', '自动翻译评论'],
        ];
        for (const [key, label] of options) {
            const enabled = settings[key];
            menuIds[key] = GM_registerMenuCommand(
                `${enabled ? '✅' : '❌'} ${label}：${enabled ? '开启' : '关闭'}`,
                () => setSetting(key, !settings[key]),
                { id: menuIds[key], autoClose: false }
            );
        }
    }

    function isChineseTranslation(button) {
        const label = (button.textContent || button.getAttribute('aria-label') || '').trim();
        return /^(?:翻[译譯](?:成|为|為)(?:(?:简体|簡體|繁体|繁體)?中文)|Translate to (?:Chinese|Simplified Chinese|Traditional Chinese))/i.test(label);
    }

    function translateCommentBatch() {
        translationTimer = 0;
        if (!settings.translateComments || commentsNavigating || !videoIdFromUrl()) return;
        let translated = 0;
        for (const button of translationQueue) {
            translationQueue.delete(button);
            const comment = button.closest('ytd-comment-view-model, ytd-comment-renderer') || button;
            if (!button.isConnected || translatedComments.has(comment) ||
                button.matches(':disabled, [aria-disabled="true"]') || !isChineseTranslation(button)) continue;
            // Record before clicking so later DOM updates and "View original" never enqueue it again.
            translatedComments.add(comment);
            button.click();
            if (++translated === 3) break;
        }
        if (translationQueue.size) translationTimer = setTimeout(translateCommentBatch, 250);
    }

    function scheduleCommentScan() {
        if (!settings.translateComments || commentsNavigating || translationFrame) return;
        translationFrame = requestAnimationFrame(() => {
            translationFrame = 0;
            for (const root of commentRoots) {
                for (const button of root.querySelectorAll('button, [role="button"]')) {
                    const comment = button.closest('ytd-comment-view-model, ytd-comment-renderer') || button;
                    if (button.querySelector('button, [role="button"]') || translatedComments.has(comment)) continue;
                    if (/^(?:查看原文|檢視原文|View original)/i.test(button.textContent.trim())) {
                        translatedComments.add(comment);
                    } else if (isChineseTranslation(button)) {
                        translationQueue.add(button);
                    }
                }
            }
            if (translationQueue.size && !translationTimer) {
                translationTimer = setTimeout(translateCommentBatch, 0);
            }
        });
    }

    function resetCommentTranslation(clearHistory = false) {
        commentObserver.disconnect();
        commentRoots.clear();
        translationQueue.clear();
        if (clearHistory) translatedComments = new WeakSet();
        cancelAnimationFrame(translationFrame);
        clearTimeout(translationTimer);
        translationFrame = 0;
        translationTimer = 0;
    }

    function syncCommentTranslation() {
        if (!settings.translateComments || commentsNavigating || !videoIdFromUrl()) return;
        for (const root of document.querySelectorAll('ytd-comments, ytd-engagement-panel-section-list-renderer[target-id*="comments"]')) {
            if (commentRoots.has(root)) continue;
            commentRoots.add(root);
            commentObserver.observe(root, {
                childList: true, characterData: true, subtree: true,
                attributes: true, attributeFilter: ['disabled', 'aria-disabled'],
            });
            scheduleCommentScan();
        }
    }

    function videoIdFromUrl() {
        const url = new URL(location.href);
        if (url.pathname === '/watch') return url.searchParams.get('v');

        const match = url.pathname.match(/^\/live\/([^/]+)/);
        return match?.[1] || null;
    }

    function getReadyPlayer(videoId) {
        const player = unsafeWindow.document.getElementById('movie_player');
        if (typeof player?.showVideoInfo !== 'function' ||
            typeof player.hideVideoInfo !== 'function' ||
            typeof player.isVideoInfoVisible !== 'function') return null;

        try {
            if (typeof player.getVideoData === 'function' &&
                player.getVideoData()?.video_id !== videoId) return null;
        } catch (_) {
            return null;
        }
        return player;
    }

    function updateButton(player) {
        const visible = player.isVideoInfoVisible();
        if (!visible) panelObserver.disconnect();
        if (!visible && openedStats?.player === player) openedStats = null;
        const label = `${visible ? '关闭' : '打开'}详细统计信息`;
        button.setAttribute('aria-pressed', String(visible));
        button.setAttribute('aria-label', label);
        button.title = label;
    }

    function toggleStats(event) {
        event.preventDefault();
        event.stopPropagation();

        const videoId = videoIdFromUrl();
        const player = videoId && getReadyPlayer(videoId);
        if (!player) return;

        try {
            if (player.isVideoInfoVisible()) {
                panelObserver.disconnect();
                player.hideVideoInfo();
                openedStats = null;
            } else {
                showStats(player);
            }
            if (currentVideo) currentVideo.statsApplied = true;
            updateButton(player);
        } catch (_) {
            panelObserver.disconnect();
            // The player may be changing videos; the next sync will restore the button.
        }
    }

    function showStats(player, automatic = false) {
        // Observe before opening so asynchronously rendered speed data is converted immediately.
        panelObserver.disconnect();
        panelObserver.observe(player, { childList: true, characterData: true, subtree: true });
        player.showVideoInfo();
        openedStats = { player, automatic };
        if (updateSpeedDisplay()) panelObserver.disconnect();
    }

    function closeOpenedStats() {
        panelObserver.disconnect();
        if (!openedStats) return;
        try {
            const { player } = openedStats;
            if (player.isVideoInfoVisible()) player.hideVideoInfo();
        } catch (_) {
            // The previous player may already have been removed.
        }
        openedStats = null;
    }

    function applyVideoDefaults(player, videoId) {
        if (currentVideo?.player !== player || currentVideo.id !== videoId) {
            currentVideo = { player, id: videoId, statsApplied: false, qualityApplied: false };
        }
        if (settings.autoStats && !currentVideo.statsApplied) {
            if (!player.isVideoInfoVisible()) showStats(player, true);
            currentVideo.statsApplied = true;
        }
        if (!settings.highestQuality || currentVideo.qualityApplied || player.classList.contains('ad-showing')) return;

        const rank = quality => quality === 'highres' ? Infinity :
            Number(quality.match(/^hd(\d+)$/)?.[1]) || ({ large: 480, medium: 360, small: 240, tiny: 144 }[quality] || 0);
        const levels = player.getAvailableQualityLevels?.().filter(quality => rank(quality) > 0);
        if (!levels?.length) return;
        const highest = levels.reduce((best, quality) => rank(quality) > rank(best) ? quality : best);
        if (typeof player.setPlaybackQualityRange === 'function') player.setPlaybackQualityRange(highest, highest);
        else if (typeof player.setPlaybackQuality === 'function') player.setPlaybackQuality(highest);
        else return;
        currentVideo.qualityApplied = true;
    }

    function observeSpeedValue(value) {
        if (value === observedSpeedValue) return;
        speedObserver.disconnect();
        observedSpeedValue = value;
        if (value) speedObserver.observe(value, { characterData: true, childList: true, subtree: true });
    }

    function updateSpeedDisplay() {
        const panel = document.querySelector('.html5-video-info-panel-content, .ytp-sfn-content');
        if (!panel) {
            observeSpeedValue(null);
            return;
        }

        const row = Array.from(panel.children).find(child =>
            /^(?:Connection Speed|连接速度)$/i.test(child.firstElementChild?.textContent?.trim() || '')
        );
        const valueCell = row?.children[1];
        if (!valueCell) {
            observeSpeedValue(null);
            return;
        }

        // Avoid a duplicate value when another converter is installed.
        if (row.querySelector('#yt-speed-converter-mbps-display')) {
            valueCell.querySelector(`#${SPEED_ID}`)?.remove();
            observeSpeedValue(null);
            return true;
        }

        const nativeSpeedValue = Array.from(valueCell.children).find(child =>
            child.id !== SPEED_ID && /Kbps\b/i.test(child.textContent)
        );
        observeSpeedValue(nativeSpeedValue || null);

        const match = (nativeSpeedValue || valueCell).textContent.match(/([\d,]+(?:\.\d+)?)\s*Kbps\b/i);
        if (!match) return;
        const kbps = Number(match[1].replaceAll(',', ''));
        if (!Number.isFinite(kbps)) return;

        let converted = valueCell.querySelector(`#${SPEED_ID}`);
        if (!converted) {
            converted = document.createElement('span');
            converted.id = SPEED_ID;
            converted.style.cssText = 'margin-left:6px;color:#63c9ff;font-weight:600;white-space:nowrap;';
            valueCell.appendChild(converted);
        }
        const display = `(${(kbps / 8192).toFixed(2)} MB/s)`;
        if (converted.textContent !== display) converted.textContent = display;
        return true;
    }

    function ensureButton(player) {
        if (!button) {
            const style = document.createElement('style');
            style.textContent = `
                #${BUTTON_ID} {
                    position: absolute;
                    top: 32px;
                    right: 32px;
                    z-index: 1000;
                    display: inline-flex;
                    align-items: center;
                    justify-content: center;
                    box-sizing: border-box;
                    width: 30px;
                    height: 30px;
                    padding: 0;
                    border: 0;
                    border-radius: 5px;
                    background: rgba(0, 0, 0, .62);
                    color: #fff;
                    cursor: pointer;
                    opacity: .9;
                    outline: none;
                    pointer-events: auto;
                    transition: background-color .15s ease, opacity .15s ease;
                }
                #${BUTTON_ID}[aria-pressed="true"] {
                    background: rgba(70, 70, 70, .88);
                    opacity: 1;
                }
                #${BUTTON_ID}:hover,
                #${BUTTON_ID}:focus-visible {
                    background: rgba(90, 90, 90, .94);
                    opacity: 1;
                }
                #${BUTTON_ID} svg {
                    display: block;
                    width: 20px;
                    height: 20px;
                    fill: currentColor;
                }
                #movie_player.ytp-autohide #${BUTTON_ID} {
                    opacity: 0 !important;
                    pointer-events: none !important;
                }
            `;
            (document.head || document.documentElement).appendChild(style);

            button = document.createElement('button');
            button.id = BUTTON_ID;
            button.type = 'button';
            const svg = document.createElementNS('http://www.w3.org/2000/svg', 'svg');
            svg.setAttribute('viewBox', '0 0 48 48');
            svg.setAttribute('aria-hidden', 'true');
            svg.setAttribute('focusable', 'false');
            const path = document.createElementNS('http://www.w3.org/2000/svg', 'path');
            path.setAttribute('d', ICON_PATH);
            svg.appendChild(path);
            button.appendChild(svg);
            button.addEventListener('click', toggleStats);
            for (const type of ['pointerdown', 'pointerup', 'mousedown', 'mouseup', 'dblclick', 'keydown']) {
                button.addEventListener(type, event => event.stopPropagation());
            }
        }
        if (button.parentElement !== player) player.appendChild(button);
    }

    function sync() {
        updateSpeedDisplay();
        syncCommentTranslation();
        const videoId = videoIdFromUrl();
        const player = videoId && getReadyPlayer(videoId);
        if (!player) {
            button?.remove();
            return;
        }

        ensureButton(player);
        try {
            applyVideoDefaults(player, videoId);
            updateButton(player);
        } catch (_) {
            // Retry when YouTube finishes initializing or replacing the player.
        }
    }

    document.addEventListener('yt-navigate-start', () => {
        closeOpenedStats();
        commentsNavigating = true;
        resetCommentTranslation(true);
        currentVideo = null;
    });
    document.addEventListener('yt-navigate-finish', () => {
        commentsNavigating = false;
        sync();
    });
    document.addEventListener('loadedmetadata', sync, true);
    document.addEventListener('DOMContentLoaded', sync, { once: true });
    window.addEventListener('pagehide', closeOpenedStats);
    updateMenus();
    setInterval(sync, 750);
    sync();
})();