// AudiOhm Web App
const API_BASE = 'http://192.168.1.204:8000/api/v1';
let authToken = localStorage.getItem('authToken') || null;
let currentUser = JSON.parse(localStorage.getItem('currentUser')) || null;
let currentTrack = null;
let isPlaying = false;

// DOM Elements (will be initialized on DOMContentLoaded)
let audioPlayer, playBtn, progressBar, volumeBar;

// API Helper Functions
async function apiRequest(endpoint, options = {}) {
    const headers = {
        'Content-Type': 'application/json',
        ...options.headers
    };

    if (authToken) {
        headers['Authorization'] = `Bearer ${authToken}`;
    }

    try {
        const response = await fetch(`${API_BASE}${endpoint}`, {
            ...options,
            headers
        });

        if (response.status === 401) {
            logout();
            return null;
        }

        const data = await response.json();
        return data;
    } catch (error) {
        console.error('API Error:', error);
        return null;
    }
}

// Auth Functions
async function login(email, password) {
    const response = await fetch(`${API_BASE}/auth/login`, {
        method: 'POST',
        headers: {
            'Content-Type': 'application/json'
        },
        body: JSON.stringify({
            email: email,
            password: password
        })
    });

    if (response.ok) {
        const data = await response.json();
        authToken = data.access_token;
        localStorage.setItem('authToken', authToken);

        // Get user info
        const user = await apiRequest('/auth/me');
        if (user) {
            currentUser = user;
            localStorage.setItem('currentUser', JSON.stringify(user));
            showMainApp();
        }
    } else {
        const error = await response.json();
        showError(error.detail || 'Email ou mot de passe incorrect');
    }
}

async function register(username, email, password) {
    const response = await apiRequest('/auth/register', {
        method: 'POST',
        body: JSON.stringify({
            username,
            email,
            password
        })
    });

    if (response) {
        showSuccess('Compte créé avec succès ! Vous pouvez maintenant vous connecter.');
        showLoginForm();
    }
}

function logout() {
    authToken = null;
    currentUser = null;
    localStorage.removeItem('authToken');
    localStorage.removeItem('currentUser');
    showLoginScreen();
}

// UI Functions
function showLoginScreen() {
    document.getElementById('loading-screen').classList.add('hidden');
    document.getElementById('login-screen').classList.remove('hidden');
    document.getElementById('main-app').classList.add('hidden');
    document.getElementById('main-app').classList.remove('visible');
}

function showMainApp() {
    document.getElementById('loading-screen').classList.add('hidden');
    document.getElementById('login-screen').classList.add('hidden');
    document.getElementById('main-app').classList.remove('hidden');
    document.getElementById('main-app').classList.add('visible');
    loadTrendingTracks();
    loadPlaylists();
}

function showLoginForm() {
    document.getElementById('login-form').classList.remove('hidden');
    document.getElementById('register-form').classList.add('hidden');
}

function showRegisterForm() {
    document.getElementById('login-form').classList.add('hidden');
    document.getElementById('register-form').classList.remove('hidden');
}

function showError(message) {
    const errorDiv = document.getElementById('auth-error');
    errorDiv.textContent = message;
    errorDiv.classList.remove('hidden');
    setTimeout(() => errorDiv.classList.add('hidden'), 5000);
}

function showSuccess(message) {
    alert(message);
}

// Music Functions
async function loadTrendingTracks() {
    const tracks = await apiRequest('/music/trending?limit=10');
    if (tracks) {
        displayTracks(tracks, 'trending-tracks');
    }
}

async function searchTracks(query) {
    const results = await apiRequest(`/music/search?q=${encodeURIComponent(query)}`);
    if (results) {
        displayTracks(results.tracks || results, 'search-results');
    }
}

function displayTracks(tracks, containerId) {
    const container = document.getElementById(containerId);
    if (!container) return;

    if (!tracks || tracks.length === 0) {
        container.innerHTML = '<p class="text-secondary">Aucun résultat</p>';
        return;
    }

    container.innerHTML = tracks.map(track => {
        const youtubeId = track.youtube_id;
        const coverUrl = track.image_url || track.thumbnail || 'https://via.placeholder.com/300x300/00F0FF/0A0E27?text=♪';
        const artistName = track.artist_name || track.artist || 'Artiste inconnu';

        // Store track data as JSON for playback
        const trackData = JSON.stringify({
            title: track.title,
            artist_name: artistName,
            image_url: coverUrl,
            duration: track.duration
        }).replace(/"/g, '&quot;');

        return `
        <div class="track-card" data-track-id="${youtubeId || track.id}" data-track="${trackData}">
            <img src="${coverUrl}" alt="${track.title}" class="track-cover" onerror="this.src='https://via.placeholder.com/300x300/00F0FF/0A0E27?text=♪'">
            <div class="track-info">
                <div class="track-title">${track.title}</div>
                <div class="track-artist">${artistName}</div>
            </div>
            <div class="track-duration">${formatDuration(track.duration)}</div>
            <div class="track-actions">
                ${youtubeId ? `<button class="btn-play-track" onclick="playTrackFromCard(this, '${youtubeId}')">
                    <i class="fas fa-play"></i> Play
                </button>` : '<span class="text-secondary">Non disponible</span>'}
            </div>
        </div>
    `;
    }).join('');
}

function playTrackFromCard(button, youtubeId) {
    // Get track data from the card element
    const card = button.closest('.track-card');
    const trackDataJSON = card.getAttribute('data-track');

    if (trackDataJSON) {
        // Parse the track data (convert &quot; back to ")
        const trackData = JSON.parse(trackDataJSON.replace(/&quot;/g, '"'));

        // Set current track with the data we have
        currentTrack = trackData;

        // Now call playTrack with the identifier
        playTrack(youtubeId, true);
    } else {
        playTrack(youtubeId, true);
    }
}

async function playTrack(identifier, isYoutubeId = true) {
    // identifier: track UUID or youtube_id
    // isYoutubeId: true if identifier is a youtube_id, false if it's a track UUID

    let streamUrl;
    let track;
    let shouldUpdateUI = false;

    if (isYoutubeId) {
        // Use YouTube streaming endpoint
        streamUrl = `${API_BASE}/music/youtube/${identifier}/stream`;
        // currentTrack should already be set by playTrackFromCard
        if (!currentTrack) {
            currentTrack = { title: 'Unknown Track', artist_name: 'Unknown Artist', image_url: null };
        }
        track = currentTrack;
        shouldUpdateUI = true;
    } else {
        // Try UUID endpoint (for tracks in database)
        streamUrl = `${API_BASE}/music/tracks/${identifier}/stream`;
        // Get track details
        track = await apiRequest(`/music/tracks/${identifier}`);
        if (track) {
            currentTrack = track;
            shouldUpdateUI = true;
        }
    }

    if (track && shouldUpdateUI) {
        // Update player UI
        const coverUrl = track.image_url || track.thumbnail || '/static/img/default-cover.png';
        document.getElementById('player-cover').src = coverUrl;
        document.getElementById('player-title').textContent = track.title;
        document.getElementById('player-artist').textContent = track.artist_name || track.artist || '-';

        // Set audio source and play
        audioPlayer.src = streamUrl;
        audioPlayer.load(); // Important: load the source before playing

        audioPlayer.play().catch(e => {
            console.error('Playback error:', e);
            showError('Erreur lors de la lecture: ' + e.message);
        });
        isPlaying = true;
        updatePlayButton();
    } else if (currentTrack) {
        // Just update the source if UI is already set
        audioPlayer.src = streamUrl;
        audioPlayer.load();

        audioPlayer.play().catch(e => {
            console.error('Playback error:', e);
            showError('Erreur lors de la lecture: ' + e.message);
        });
        isPlaying = true;
        updatePlayButton();
    } else {
        showError('Impossible de lire ce morceau');
    }
}

function togglePlay() {
    if (!currentTrack) return;

    if (isPlaying) {
        audioPlayer.pause();
    } else {
        audioPlayer.play();
    }
    isPlaying = !isPlaying;
    updatePlayButton();
}

function updatePlayButton() {
    playBtn.innerHTML = isPlaying ? '<i class="fas fa-pause"></i>' : '<i class="fas fa-play"></i>';
}

// Playlist Functions
async function loadPlaylists() {
    const playlists = await apiRequest('/playlists');
    if (playlists) {
        displayPlaylists(playlists);
    }
}

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

    if (!playlists || playlists.length === 0) {
        container.innerHTML = '<p class="text-secondary">Aucune playlist</p>';
        return;
    }

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

// Utility Functions
function formatDuration(seconds) {
    if (!seconds) return '0:00';
    const mins = Math.floor(seconds / 60);
    const secs = seconds % 60;
    return `${mins}:${secs.toString().padStart(2, '0')}`;
}

// Navigation
function navigateTo(page) {
    // Update nav items
    document.querySelectorAll('.nav-item').forEach(item => {
        item.classList.remove('active');
        if (item.dataset.page === page) {
            item.classList.add('active');
        }
    });

    // Show/hide pages
    document.querySelectorAll('.page').forEach(p => {
        p.classList.remove('active');
    });
    document.getElementById(`${page}-page`).classList.add('active');
}

// Event Listeners
document.addEventListener('DOMContentLoaded', function() {
    // Initialize DOM Elements
    audioPlayer = document.getElementById('audio-player');
    playBtn = document.getElementById('play-btn');
    progressBar = document.getElementById('progress-bar');
    volumeBar = document.getElementById('volume-bar');

    // Check auth status
    if (authToken && currentUser) {
        showMainApp();
    } else {
        showLoginScreen();
    }

    // Login form
    document.getElementById('login-form').addEventListener('submit', function(e) {
        e.preventDefault();
        const email = document.getElementById('login-email').value;
        const password = document.getElementById('login-password').value;
        login(email, password);
    });

    // Register form
    document.getElementById('register-form').addEventListener('submit', function(e) {
        e.preventDefault();
        const username = document.getElementById('register-username').value;
        const email = document.getElementById('register-email').value;
        const password = document.getElementById('register-password').value;
        register(username, email, password);
    });

    // Show register form
    document.getElementById('show-register').addEventListener('click', function(e) {
        e.preventDefault();
        showRegisterForm();
    });

    // Show login form
    document.getElementById('show-login').addEventListener('click', function(e) {
        e.preventDefault();
        showLoginForm();
    });

    // Logout
    document.getElementById('logout-btn').addEventListener('click', logout);

    // Navigation
    document.querySelectorAll('.nav-item').forEach(item => {
        item.addEventListener('click', function(e) {
            e.preventDefault();
            navigateTo(this.dataset.page);
        });
    });

    // Quick search
    document.getElementById('quick-search-btn').addEventListener('click', function() {
        const query = document.getElementById('quick-search').value;
        if (query) {
            navigateTo('search');
            searchTracks(query);
        }
    });

    // Search
    document.getElementById('search-btn').addEventListener('click', function() {
        const query = document.getElementById('search-input').value;
        if (query) {
            searchTracks(query);
        }
    });

    // Player controls
    playBtn.addEventListener('click', togglePlay);

    // Audio events
    audioPlayer.addEventListener('loadedmetadata', function() {
        const duration = audioPlayer.duration;
        document.getElementById('total-time').textContent = formatDuration(Math.floor(duration));
    });

    audioPlayer.addEventListener('timeupdate', function() {
        const current = audioPlayer.currentTime;
        const duration = audioPlayer.duration;
        const progress = (current / duration) * 100;
        progressBar.value = progress;
        document.getElementById('current-time').textContent = formatDuration(Math.floor(current));
    });

    audioPlayer.addEventListener('ended', function() {
        isPlaying = false;
        updatePlayButton();
    });

    progressBar.addEventListener('input', function() {
        const duration = audioPlayer.duration;
        audioPlayer.currentTime = (this.value / 100) * duration;
    });

    volumeBar.addEventListener('input', function() {
        audioPlayer.volume = this.value / 100;
    });
});