/**
 * ============================================
 * AUDIOHM WEB PLAYER - OPTIMIZED
 * Version: 2.0
 * Last Updated: 2026-01-19
 * ============================================
 */

// ============================================
// STATE MANAGEMENT
// ============================================
const AppState = {
    isAuthenticated: false,
    currentPage: 'home',
    currentTrack: null,
    isPlaying: false,
    isShuffle: false,
    repeatMode: 'none', // none, one, all
    volume: 100,
    isMuted: false,
    likedTracks: new Set(),
    playlists: [],
    queue: []
};

// ============================================
// DOM ELEMENTS
// ============================================
const DOM = {
    // Screens
    loadingScreen: null,
    loginScreen: null,
    mainApp: null,

    // Forms
    loginForm: null,
    registerForm: null,
    authError: null,

    // Navigation
    sidebar: null,
    navItems: null,
    mobileMenuBtn: null,
    logoutBtn: null,

    // Pages
    pages: {},

    // Player
    audioPlayer: null,
    playBtn: null,
    prevBtn: null,
    nextBtn: null,
    shuffleBtn: null,
    repeatBtn: null,
    progressBar: null,
    volumeBar: null,
    muteBtn: null,
    likeBtn: null,
    playerCover: null,
    playerTitle: null,
    playerArtist: null,
    currentTime: null,
    totalTime: null,

    // Toast
    toastContainer: null
};

// ============================================
// INITIALIZATION
// ============================================
function init() {
    // Cache DOM elements
    cacheDOM();

    // Check authentication
    checkAuth();

    // Setup event listeners
    setupEventListeners();

    // Hide loading screen
    hideLoadingScreen();
}

function cacheDOM() {
    DOM.loadingScreen = document.getElementById('loading-screen');
    DOM.loginScreen = document.getElementById('login-screen');
    DOM.mainApp = document.getElementById('main-app');

    DOM.loginForm = document.getElementById('login-form');
    DOM.registerForm = document.getElementById('register-form');
    DOM.authError = document.getElementById('auth-error');

    DOM.sidebar = document.getElementById('sidebar');
    DOM.navItems = document.querySelectorAll('.nav-item');
    DOM.mobileMenuBtn = document.getElementById('mobile-menu-btn');
    DOM.logoutBtn = document.getElementById('logout-btn');

    ['home', 'search', 'library'].forEach(page => {
        DOM.pages[page] = document.getElementById(`${page}-page`);
    });

    DOM.audioPlayer = document.getElementById('audio-player');
    DOM.playBtn = document.getElementById('play-btn');
    DOM.prevBtn = document.getElementById('prev-btn');
    DOM.nextBtn = document.getElementById('next-btn');
    DOM.shuffleBtn = document.getElementById('shuffle-btn');
    DOM.repeatBtn = document.getElementById('repeat-btn');
    DOM.progressBar = document.getElementById('progress-bar');
    DOM.volumeBar = document.getElementById('volume-bar');
    DOM.muteBtn = document.getElementById('mute-btn');
    DOM.likeBtn = document.getElementById('like-btn');
    DOM.playerCover = document.getElementById('player-cover');
    DOM.playerTitle = document.getElementById('player-title');
    DOM.playerArtist = document.getElementById('player-artist');
    DOM.currentTime = document.getElementById('current-time');
    DOM.totalTime = document.getElementById('total-time');

    DOM.toastContainer = document.getElementById('toast-container');
}

// ============================================
// EVENT LISTENERS
// ============================================
function setupEventListeners() {
    // Auth forms
    if (DOM.loginForm) {
        DOM.loginForm.addEventListener('submit', handleLogin);
    }

    if (DOM.registerForm) {
        DOM.registerForm.addEventListener('submit', handleRegister);
    }

    // Show/hide register forms
    const showRegister = document.getElementById('show-register');
    const showLogin = document.getElementById('show-login');

    if (showRegister) {
        showRegister.addEventListener('click', (e) => {
            e.preventDefault();
            DOM.loginForm.classList.add('hidden');
            DOM.registerForm.classList.remove('hidden');
        });
    }

    if (showLogin) {
        showLogin.addEventListener('click', (e) => {
            e.preventDefault();
            DOM.registerForm.classList.add('hidden');
            DOM.loginForm.classList.remove('hidden');
        });
    }

    // Navigation
    DOM.navItems.forEach(item => {
        item.addEventListener('click', (e) => {
            e.preventDefault();
            const page = item.dataset.page;
            navigateTo(page);
        });
    });

    // Mobile menu
    if (DOM.mobileMenuBtn) {
        DOM.mobileMenuBtn.addEventListener('click', toggleMobileMenu);
    }

    // Logout
    if (DOM.logoutBtn) {
        DOM.logoutBtn.addEventListener('click', handleLogout);
    }

    // Player controls
    setupPlayerControls();
}

function setupPlayerControls() {
    // Play/Pause
    if (DOM.playBtn) {
        DOM.playBtn.addEventListener('click', togglePlayPause);
    }

    // Previous/Next
    if (DOM.prevBtn) {
        DOM.prevBtn.addEventListener('click', playPrevious);
    }

    if (DOM.nextBtn) {
        DOM.nextBtn.addEventListener('click', playNext);
    }

    // Shuffle
    if (DOM.shuffleBtn) {
        DOM.shuffleBtn.addEventListener('click', toggleShuffle);
    }

    // Repeat
    if (DOM.repeatBtn) {
        DOM.repeatBtn.addEventListener('click', toggleRepeat);
    }

    // Progress bar
    if (DOM.progressBar) {
        DOM.progressBar.addEventListener('input', handleSeek);
    }

    // Volume
    if (DOM.volumeBar) {
        DOM.volumeBar.addEventListener('input', handleVolumeChange);
    }

    // Mute
    if (DOM.muteBtn) {
        DOM.muteBtn.addEventListener('click', toggleMute);
    }

    // Like
    if (DOM.likeBtn) {
        DOM.likeBtn.addEventListener('click', toggleLike);
    }

    // Audio events
    if (DOM.audioPlayer) {
        DOM.audioPlayer.addEventListener('timeupdate', updateProgress);
        DOM.audioPlayer.addEventListener('loadedmetadata', updateDuration);
        DOM.audioPlayer.addEventListener('ended', handleTrackEnd);
    }
}

// ============================================
// AUTHENTICATION
// ============================================
async function checkAuth() {
    const token = localStorage.getItem('token');

    if (!token) {
        showScreen('login');
        return;
    }

    try {
        const response = await fetch('/api/v1/auth/me', {
            headers: {
                'Authorization': `Bearer ${token}`
            }
        });

        if (response.ok) {
            AppState.isAuthenticated = true;
            showScreen('main');
            loadUserData();
        } else {
            localStorage.removeItem('token');
            showScreen('login');
        }
    } catch (error) {
        console.error('Auth check failed:', error);
        showScreen('login');
    }
}

async function handleLogin(e) {
    e.preventDefault();

    const email = document.getElementById('login-email').value;
    const password = document.getElementById('login-password').value;

    try {
        const response = await fetch('/api/v1/auth/login', {
            method: 'POST',
            headers: {
                'Content-Type': 'application/json'
            },
            body: JSON.stringify({ email, password })
        });

        const data = await response.json();

        if (response.ok) {
            localStorage.setItem('token', data.access_token);
            AppState.isAuthenticated = true;
            showScreen('main');
            showToast('Connexion réussie!', 'success');
        } else {
            showError(data.detail || 'Email ou mot de passe incorrect');
        }
    } catch (error) {
        console.error('Login failed:', error);
        showError('Erreur de connexion');
    }
}

async function handleRegister(e) {
    e.preventDefault();

    const username = document.getElementById('register-username').value;
    const email = document.getElementById('register-email').value;
    const password = document.getElementById('register-password').value;

    try {
        const response = await fetch('/api/v1/auth/register', {
            method: 'POST',
            headers: {
                'Content-Type': 'application/json'
            },
            body: JSON.stringify({ username, email, password })
        });

        const data = await response.json();

        if (response.ok) {
            localStorage.setItem('token', data.access_token);
            AppState.isAuthenticated = true;
            showScreen('main');
            showToast('Compte créé avec succès!', 'success');
        } else {
            showError(data.detail || 'Erreur lors de la création du compte');
        }
    } catch (error) {
        console.error('Register failed:', error);
        showError('Erreur de connexion');
    }
}

function handleLogout() {
    localStorage.removeItem('token');
    AppState.isAuthenticated = false;
    showScreen('login');
    showToast('Déconnexion réussie', 'success');
}

// ============================================
// NAVIGATION
// ============================================
function navigateTo(page) {
    // Update active nav item
    DOM.navItems.forEach(item => {
        item.classList.remove('active');
        if (item.dataset.page === page) {
            item.classList.add('active');
        }
    });

    // Show/hide pages
    Object.keys(DOM.pages).forEach(key => {
        if (key === page) {
            DOM.pages[key].classList.add('active');
        } else {
            DOM.pages[key].classList.remove('active');
        }
    });

    AppState.currentPage = page;

    // Close mobile menu
    DOM.sidebar.classList.remove('open');
}

function toggleMobileMenu() {
    DOM.sidebar.classList.toggle('open');
}

// Close menu when clicking outside
document.addEventListener('click', (e) => {
    if (!DOM.sidebar?.contains(e.target) && !DOM.mobileMenuBtn?.contains(e.target)) {
        DOM.sidebar?.classList.remove('open');
    }
});

// ============================================
// PLAYER CONTROLS
// ============================================
function togglePlayPause() {
    if (!DOM.audioPlayer) return;

    if (DOM.audioPlayer.paused) {
        DOM.audioPlayer.play();
        updatePlayButton(true);
    } else {
        DOM.audioPlayer.pause();
        updatePlayButton(false);
    }
}

function updatePlayButton(isPlaying) {
    const icon = DOM.playBtn?.querySelector('i');
    if (!icon) return;

    if (isPlaying) {
        icon.classList.remove('fa-play');
        icon.classList.add('fa-pause');
    } else {
        icon.classList.remove('fa-pause');
        icon.classList.add('fa-play');
    }
}

function playPrevious() {
    // Implement previous track logic
    showToast('Non disponible pour le moment', 'error');
}

function playNext() {
    // Implement next track logic
    showToast('Non disponible pour le moment', 'error');
}

function toggleShuffle() {
    AppState.isShuffle = !AppState.isShuffle;

    if (DOM.shuffleBtn) {
        DOM.shuffleBtn.classList.toggle('active', AppState.isShuffle);
    }

    showToast(AppState.isShuffle ? 'Aléatoire activé' : 'Aléatoire désactivé', 'success');
}

function toggleRepeat() {
    const modes = ['none', 'all', 'one'];
    const currentIndex = modes.indexOf(AppState.repeatMode);
    const nextIndex = (currentIndex + 1) % modes.length;
    AppState.repeatMode = modes[nextIndex];

    if (DOM.repeatBtn) {
        DOM.repeatBtn.classList.remove('active');
        if (AppState.repeatMode !== 'none') {
            DOM.repeatBtn.classList.add('active');
        }
    }

    const messages = {
        none: 'Répétition désactivée',
        all: 'Répétition de toutes les pistes',
        one: 'Répétition de la piste actuelle'
    };

    showToast(messages[AppState.repeatMode], 'success');
}

function handleSeek() {
    if (!DOM.audioPlayer || !DOM.progressBar) return;

    const time = (DOM.progressBar.value / 100) * DOM.audioPlayer.duration;
    DOM.audioPlayer.currentTime = time;
}

function handleVolumeChange() {
    if (!DOM.audioPlayer || !DOM.volumeBar) return;

    AppState.volume = DOM.volumeBar.value;
    DOM.audioPlayer.volume = AppState.volume / 100;
    AppState.isMuted = false;
    updateVolumeIcon();
}

function toggleMute() {
    if (!DOM.audioPlayer) return;

    AppState.isMuted = !AppState.isMuted;
    DOM.audioPlayer.muted = AppState.isMuted;
    updateVolumeIcon();
}

function updateVolumeIcon() {
    const icon = DOM.muteBtn?.querySelector('i');
    if (!icon) return;

    icon.className = 'fas';

    if (AppState.isMuted || AppState.volume === 0) {
        icon.classList.add('fa-volume-mute');
    } else if (AppState.volume < 50) {
        icon.classList.add('fa-volume-down');
    } else {
        icon.classList.add('fa-volume-up');
    }
}

function toggleLike() {
    if (!DOM.likeBtn) return;

    const trackId = DOM.likeBtn.dataset.trackId;
    if (!trackId) return;

    if (AppState.likedTracks.has(trackId)) {
        AppState.likedTracks.delete(trackId);
        DOM.likeBtn.classList.remove('liked');
        DOM.likeBtn.querySelector('i').classList.replace('fas', 'far');
        showToast('Retiré des titres likés', 'success');
    } else {
        AppState.likedTracks.add(trackId);
        DOM.likeBtn.classList.add('liked');
        DOM.likeBtn.querySelector('i').classList.replace('far', 'fas');
        showToast('Ajouté aux titres likés', 'success');
    }
}

function updateProgress() {
    if (!DOM.audioPlayer || !DOM.progressBar) return;

    const progress = (DOM.audioPlayer.currentTime / DOM.audioPlayer.duration) * 100;
    DOM.progressBar.value = progress;

    if (DOM.currentTime) {
        DOM.currentTime.textContent = formatTime(DOM.audioPlayer.currentTime);
    }
}

function updateDuration() {
    if (!DOM.audioPlayer || !DOM.totalTime) return;

    DOM.totalTime.textContent = formatTime(DOM.audioPlayer.duration);
}

function handleTrackEnd() {
    if (AppState.repeatMode === 'one') {
        DOM.audioPlayer.currentTime = 0;
        DOM.audioPlayer.play();
    } else if (AppState.repeatMode === 'all') {
        playNext();
    } else {
        updatePlayButton(false);
    }
}

// ============================================
// UTILITY FUNCTIONS
// ============================================
function formatTime(seconds) {
    if (!seconds || isNaN(seconds)) return '0:00';

    const mins = Math.floor(seconds / 60);
    const secs = Math.floor(seconds % 60);

    return `${mins}:${secs.toString().padStart(2, '0')}`;
}

function showScreen(screen) {
    if (DOM.loadingScreen) DOM.loadingScreen.classList.add('hidden');
    if (DOM.loginScreen) DOM.loginScreen.classList.toggle('hidden', screen !== 'login');
    if (DOM.mainApp) {
        DOM.mainApp.classList.toggle('hidden', screen !== 'main');
        if (screen === 'main') {
            DOM.mainApp.classList.add('visible');
        }
    }
}

function hideLoadingScreen() {
    if (DOM.loadingScreen) {
        setTimeout(() => {
            DOM.loadingScreen.style.display = 'none';
        }, 500);
    }
}

function showError(message) {
    if (DOM.authError) {
        DOM.authError.textContent = message;
        DOM.authError.classList.remove('hidden');
    }
}

async function loadUserData() {
    // Load playlists, liked tracks, etc.
    await loadPlaylists();
    await loadTrendingTracks();
}

async function loadPlaylists() {
    const container = document.getElementById('my-playlists');
    if (!container) return;

    try {
        const token = localStorage.getItem('token');
        const response = await fetch('/api/v1/playlists', {
            headers: {
                'Authorization': `Bearer ${token}`
            }
        });

        if (response.ok) {
            const playlists = await response.json();
            AppState.playlists = playlists;
            renderPlaylists(playlists);
        }
    } catch (error) {
        console.error('Failed to load playlists:', error);
        container.innerHTML = '<p style="color: var(--text-secondary);">Erreur de chargement</p>';
    }
}

function renderPlaylists(playlists) {
    const container = document.getElementById('my-playlists');
    if (!container) return;

    if (playlists.length === 0) {
        container.innerHTML = '<p style="color: var(--text-secondary);">Aucune playlist</p>';
        return;
    }

    container.innerHTML = playlists.map(playlist => `
        <div class="card playlist-card" data-id="${playlist.id}">
            <img src="${playlist.cover || '/static/img/default-cover.png'}" alt="${playlist.name}" class="playlist-cover">
            <h3 class="playlist-name">${playlist.name}</h3>
            <p class="playlist-info">${playlist.track_count || 0} pistes</p>
        </div>
    `).join('');
}

async function loadTrendingTracks() {
    const container = document.getElementById('trending-tracks');
    if (!container) return;

    try {
        const token = localStorage.getItem('token');
        const response = await fetch('/api/v1/music/trending', {
            headers: {
                'Authorization': `Bearer ${token}`
            }
        });

        if (response.ok) {
            const tracks = await response.json();
            renderTracks(tracks, container);
        }
    } catch (error) {
        console.error('Failed to load trending tracks:', error);
        container.innerHTML = '<p style="color: var(--text-secondary);">Erreur de chargement</p>';
    }
}

function renderTracks(tracks, container) {
    if (!container) return;

    if (tracks.length === 0) {
        container.innerHTML = '<p style="color: var(--text-secondary);">Aucun résultat</p>';
        return;
    }

    container.innerHTML = tracks.map(track => `
        <div class="card track-card" data-id="${track.id}">
            <img src="${track.cover || '/static/img/default-cover.png'}" alt="${track.title}" class="track-cover">
            <div class="track-info">
                <h3 class="track-title">${track.title}</h3>
                <p class="track-artist">${track.artist}</p>
            </div>
            <span class="track-duration">${formatTime(track.duration)}</span>
            <button class="btn btn-primary btn-play-track" onclick="playTrack(${track.id})">
                <i class="fas fa-play"></i>
            </button>
        </div>
    `).join('');
}

// Global function to play a track
window.playTrack = async function(trackId) {
    try {
        const token = localStorage.getItem('token');
        const response = await fetch(`/api/v1/music/${trackId}`, {
            headers: {
                'Authorization': `Bearer ${token}`
            }
        });

        if (response.ok) {
            const track = await response.json();

            // Update player
            if (DOM.audioPlayer) {
                DOM.audioPlayer.src = track.stream_url;
                DOM.audioPlayer.play();
                updatePlayButton(true);
            }

            if (DOM.playerTitle) DOM.playerTitle.textContent = track.title;
            if (DOM.playerArtist) DOM.playerArtist.textContent = track.artist;
            if (DOM.playerCover) DOM.playerCover.src = track.cover || '/static/img/default-cover.png';

            AppState.currentTrack = track;
        }
    } catch (error) {
        console.error('Failed to play track:', error);
        showToast('Erreur lors de la lecture', 'error');
    }
};

// ============================================
// TOAST NOTIFICATIONS
// ============================================
function showToast(message, type = 'success') {
    if (!DOM.toastContainer) return;

    const toast = document.createElement('div');
    toast.className = `toast ${type}`;

    const icon = type === 'success' ? 'check-circle' : 'exclamation-circle';

    toast.innerHTML = `
        <i class="fas fa-${icon}"></i>
        <span>${message}</span>
    `;

    DOM.toastContainer.appendChild(toast);

    setTimeout(() => {
        toast.style.animation = 'toastSlideOut 0.4s ease forwards';
        setTimeout(() => toast.remove(), 400);
    }, 3000);
}

// ============================================
// KEYBOARD SHORTCUTS
// ============================================
document.addEventListener('keydown', (e) => {
    // Don't trigger if typing in input
    if (e.target.tagName === 'INPUT' || e.target.tagName === 'TEXTAREA') return;

    switch(e.code) {
        case 'Space':
            e.preventDefault();
            togglePlayPause();
            break;
        case 'ArrowRight':
            if (e.shiftKey) playNext();
            else if (DOM.audioPlayer) DOM.audioPlayer.currentTime += 10;
            break;
        case 'ArrowLeft':
            if (e.shiftKey) playPrevious();
            else if (DOM.audioPlayer) DOM.audioPlayer.currentTime -= 10;
            break;
        case 'ArrowUp':
            e.preventDefault();
            if (DOM.volumeBar) {
                DOM.volumeBar.value = Math.min(100, parseInt(DOM.volumeBar.value) + 10);
                handleVolumeChange();
            }
            break;
        case 'ArrowDown':
            e.preventDefault();
            if (DOM.volumeBar) {
                DOM.volumeBar.value = Math.max(0, parseInt(DOM.volumeBar.value) - 10);
                handleVolumeChange();
            }
            break;
        case 'KeyM':
            toggleMute();
            break;
    }
});

// ============================================
// INIT
// ============================================
if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', init);
} else {
    init();
}