// ==UserScript==
// @name         YouTube Global Volume Control
// @namespace    http://tampermonkey.net/
// @version      2.0
// @description  Control YouTube volume up to 500% in 5% steps, regardless of player focus, with a fixed indicator in the center of the screen.
// @author       motorrin
// @match        https://*.youtube.com/*
// @grant        unsafeWindow
// @run-at       document-start
// ==/UserScript==

(function() {
    'use strict';

    const w = typeof unsafeWindow !== 'undefined' ? unsafeWindow : window;
    let hud = null;
    let hudTimeout = null;
    let cachedPlayer = null;
    let cachedVideo = null;
    let audioCtx = null;

    function setupAudioContext(video) {
        if (!video) return null;

        if (video._gainNode) {
            if (audioCtx && audioCtx.state === 'suspended') {
                audioCtx.resume();
            }
            return video._gainNode;
        }

        try {
            const AudioCtx = w.AudioContext || w.webkitAudioContext;
            if (!AudioCtx) return null;

            if (!audioCtx) {
                audioCtx = new AudioCtx();
            }
            if (audioCtx.state === 'suspended') {
                audioCtx.resume();
            }

            const source = audioCtx.createMediaElementSource(video);
            const gainNode = audioCtx.createGain();

            source.connect(gainNode);
            gainNode.connect(audioCtx.destination);

            video._gainNode = gainNode;
            video._audioSource = source;

            return gainNode;
        } catch (err) {
            console.error('[YT Volume Control] AudioContext error:', err);
            return null;
        }
    }

    function showVolumeHUD(volume) {
        const doc = w.document;

        const parent = doc.fullscreenElement || doc.body;
        if (!parent) return;

        if (!hud) {
            hud = doc.createElement('div');
            hud.id = 'yt-global-volume-hud';
            hud.style.cssText = `
                position: fixed;
                top: 50%;
                left: 50%;
                transform: translate(-50%, -50%);
                background: rgba(0, 0, 0, 0.8);
                color: #ffffff;
                font-size: 28px;
                font-weight: bold;
                font-family: "YouTube Sans", Roboto, Arial, sans-serif;
                padding: 10px 22px;
                border-radius: 8px;
                z-index: 2147483647;
                pointer-events: none;
                opacity: 0;
                user-select: none;
                box-shadow: 0 4px 12px rgba(0, 0, 0, 0.6);
                letter-spacing: 0.5px;
            `;
        }

        if (hud.parentNode !== parent) {
            parent.appendChild(hud);
        }

        let icon = '🔊';
        if (volume === 0) icon = '🔇';
        else if (volume < 35) icon = '🔈';
        else if (volume < 70) icon = '🔉';
        else if (volume > 100) icon = '⚡';

        hud.textContent = `${icon} ${volume}%`;

        hud.style.transition = 'none';
        hud.style.opacity = '1';

        void hud.offsetHeight;

        hud.style.transition = 'opacity 0.15s ease-out';

        if (hudTimeout) {
            clearTimeout(hudTimeout);
        }

        hudTimeout = setTimeout(() => {
            hud.style.opacity = '0';
        }, 900);
    }

    function getNextVolume(current, isUp) {
        const rounded = Math.round(current);
        return isUp
            ? Math.min(500, Math.floor(rounded / 5) * 5 + 5)
            : Math.max(0, Math.ceil(rounded / 5) * 5 - 5);
    }

    w.addEventListener('keydown', function(e) {
        if (e.key !== 'ArrowUp' && e.key !== 'ArrowDown') return;
        if (w.location.pathname.startsWith('/shorts/')) return;

        const active = w.document.activeElement;
        if (active) {
            const role = active.getAttribute('role');
            if (
                active.tagName === 'INPUT' ||
                active.tagName === 'TEXTAREA' ||
                active.tagName === 'SELECT' ||
                active.isContentEditable ||
                role === 'textbox' ||
                role === 'combobox' ||
                role === 'slider' ||
                role === 'menuitem' ||
                role === 'menuitemradio' ||
                role === 'menuitemcheckbox' ||
                role === 'option'
            ) {
                return;
            }
        }

        if (!cachedPlayer || !cachedPlayer.isConnected) {
            cachedPlayer = w.document.getElementById('movie_player') || w.document.querySelector('.html5-video-player');
        }
        if (!cachedVideo || !cachedVideo.isConnected) {
            cachedVideo = w.document.querySelector('video');
        }

        const player = cachedPlayer;
        const video = cachedVideo;

        if (!player && !video) return;

        const isWatchPage = w.location.pathname.startsWith('/watch') || w.location.pathname.startsWith('/embed/');
        const isPlaying = video && !video.paused;

        if (!isWatchPage && !isPlaying) return;

        e.preventDefault();
        e.stopImmediatePropagation();

        const isUp = e.key === 'ArrowUp';

        let currentVolume = typeof video._customVolume === 'number' ? video._customVolume : 100;
        if (typeof video._customVolume !== 'number') {
            if (player && typeof player.getVolume === 'function') {
                currentVolume = player.getVolume();
            } else if (video) {
                currentVolume = video.volume * 100;
            }
        }

        const nextVolume = getNextVolume(currentVolume, isUp);
        video._customVolume = nextVolume;

        if (player && typeof player.isMuted === 'function' && player.isMuted()) {
            if (typeof player.unMute === 'function') player.unMute();
        }
        if (video && video.muted) {
            video.muted = false;
        }

        if (nextVolume <= 100) {
            if (player && typeof player.setVolume === 'function') {
                try { player.setVolume(nextVolume); } catch (err) {}
            } else if (video) {
                try { video.volume = nextVolume / 100; } catch (err) {}
            }

            if (video._gainNode) {
                try { video._gainNode.gain.value = 1.0; } catch (err) {}
            }
        } else {
            if (player && typeof player.setVolume === 'function') {
                try { player.setVolume(100); } catch (err) {}
            } else if (video) {
                try { video.volume = 1.0; } catch (err) {}
            }

            const gainNode = setupAudioContext(video);
            if (gainNode) {
                try { gainNode.gain.value = nextVolume / 100; } catch (err) {}
            }
        }

        showVolumeHUD(nextVolume);
    }, true);
})();