// Movie Night — Frontend Logic

const API = '';
let currentUser = null;
let selectedUserIds = [];

// --- Auth ---

async function checkAuth() {
    try {
        const res = await fetch(`${API}/api/auth/me`);
        if (res.ok) {
            currentUser = await res.json();
            showMainScreen();
        } else {
            showLoginScreen();
        }
    } catch {
        showLoginScreen();
    }
}

async function login(username, password) {
    const res = await fetch(`${API}/api/auth/login`, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ username, password })
    });
    if (!res.ok) {
        const err = await res.json().catch(() => ({ detail: 'Login failed' }));
        throw new Error(err.detail || 'Login failed');
    }
    currentUser = await res.json();
    showMainScreen();
}

async function logout() {
    await fetch(`${API}/api/auth/logout`, { method: 'POST' });
    currentUser = null;
    showLoginScreen();
}

// --- Screens ---

function showLoginScreen() {
    document.getElementById('login-screen').classList.remove('hidden');
    document.getElementById('main-screen').classList.add('hidden');
}

function showMainScreen() {
    document.getElementById('login-screen').classList.add('hidden');
    document.getElementById('main-screen').classList.remove('hidden');
    document.getElementById('user-name').textContent = currentUser.name;
    selectedUserIds = [currentUser.id];
    loadUsers();
    loadStats();
    loadHistory();
}

// --- Users ---

async function loadUsers() {
    try {
        const res = await fetch(`${API}/api/users`);
        if (!res.ok) return;
        const users = await res.json();
        const container = document.getElementById('user-pills');
        container.innerHTML = '';
        users.forEach(user => {
            const pill = document.createElement('button');
            pill.className = `user-pill border rounded-full px-4 py-1.5 text-sm ${selectedUserIds.includes(user.id) ? 'active' : ''}`;
            pill.textContent = user.name;
            pill.onclick = () => toggleUser(user.id, pill);
            container.appendChild(pill);
        });
    } catch { /* ignore */ }
}

function toggleUser(userId, pill) {
    if (selectedUserIds.includes(userId)) {
        if (selectedUserIds.length > 1) {
            selectedUserIds = selectedUserIds.filter(id => id !== userId);
            pill.classList.remove('active');
        }
    } else {
        selectedUserIds.push(userId);
        pill.classList.add('active');
    }
}

// --- Mood / Recommendations ---

async function findMovies() {
    const mood = document.getElementById('mood-input').value.trim();
    if (!mood) return;

    document.getElementById('empty-state').classList.add('hidden');
    document.getElementById('results').classList.add('hidden');
    document.getElementById('error-state').classList.add('hidden');
    document.getElementById('loading').classList.remove('hidden');

    try {
        const additionalIds = selectedUserIds.filter(id => id !== currentUser.id);
        const res = await fetch(`${API}/api/mood`, {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify({ mood, additional_user_ids: additionalIds })
        });

        if (!res.ok) {
            const err = await res.json().catch(() => ({ detail: 'Something went wrong' }));
            throw new Error(err.detail || 'Failed to get recommendations');
        }

        const data = await res.json();
        renderResults(data);
        loadHistory();
    } catch (err) {
        document.getElementById('loading').classList.add('hidden');
        document.getElementById('error-message').textContent = err.message;
        document.getElementById('error-state').classList.remove('hidden');
    }
}

function renderResults(data) {
    document.getElementById('loading').classList.add('hidden');

    const grid = document.getElementById('results-grid');
    grid.innerHTML = '';

    if (!data.recommendations || data.recommendations.length === 0) {
        document.getElementById('empty-state').classList.remove('hidden');
        return;
    }

    data.recommendations.forEach(movie => {
        const card = document.createElement('div');
        card.className = 'movie-card bg-dark-200 rounded-xl overflow-hidden border border-gray-800';
        card.innerHTML = `
            <div class="aspect-[2/3] bg-dark-300 relative">
                <img src="${movie.poster_url}" alt="${movie.title}"
                    class="w-full h-full object-cover"
                    onerror="this.style.display='none'; this.nextElementSibling.style.display='flex';">
                <div class="absolute inset-0 flex items-center justify-center text-gray-600 text-lg font-semibold" style="display:none;">
                    ${movie.title}
                </div>
            </div>
            <div class="p-4">
                <h3 class="font-semibold text-lg leading-tight">${movie.title}</h3>
                <div class="flex items-center gap-2 mt-1 text-sm text-gray-400">
                    ${movie.year ? `<span>${movie.year}</span>` : ''}
                    ${movie.runtime_minutes ? `<span>&middot; ${movie.runtime_minutes}m</span>` : ''}
                    ${movie.community_rating ? `<span>&middot; ★ ${movie.community_rating.toFixed(1)}</span>` : ''}
                    ${movie.content_rating ? `<span>&middot; ${movie.content_rating}</span>` : ''}
                </div>
                <div class="flex flex-wrap gap-1 mt-2">
                    ${movie.genres.slice(0, 3).map(g => `<span class="genre-pill">${g}</span>`).join('')}
                </div>
                <p class="text-sm text-gray-400 mt-3 italic leading-relaxed">${movie.reasoning}</p>
                <a href="${movie.deep_link}" target="_blank"
                    class="block mt-4 text-center py-2 bg-indigo-600 hover:bg-indigo-700 rounded-lg font-semibold transition-colors text-sm">
                    Watch
                </a>
            </div>
        `;
        grid.appendChild(card);
    });

    const meta = data.meta;
    document.getElementById('results-meta').textContent =
        `Evaluated ${meta.candidates_evaluated} of ${meta.total_unwatched} unwatched movies in ${(meta.processing_time_ms / 1000).toFixed(1)}s`;

    document.getElementById('results').classList.remove('hidden');
}

// --- Search History ---

async function loadHistory() {
    try {
        const res = await fetch(`${API}/api/history`);
        if (!res.ok) return;
        const history = await res.json();
        const list = document.getElementById('history-list');
        list.innerHTML = '';

        if (history.length === 0) {
            document.getElementById('history-section').classList.add('hidden');
            document.getElementById('history-toggle').classList.add('hidden');
            return;
        }

        history.forEach(entry => {
            const date = new Date(entry.created_at);
            const timeStr = date.toLocaleDateString(undefined, { month: 'short', day: 'numeric' }) +
                ' ' + date.toLocaleTimeString(undefined, { hour: 'numeric', minute: '2-digit' });
            const movieTitles = entry.results.slice(0, 3).map(r => r.title).join(', ');
            const more = entry.results.length > 3 ? ` +${entry.results.length - 3} more` : '';

            const item = document.createElement('div');
            item.className = 'history-item bg-dark-200 border border-gray-800 rounded-lg p-3 cursor-pointer hover:border-gray-600 transition-colors';
            item.innerHTML = `
                <div class="flex items-start justify-between gap-3">
                    <div class="flex-1 min-w-0">
                        <p class="text-sm font-medium text-gray-200 truncate">"${entry.mood}"</p>
                        <p class="text-xs text-gray-500 mt-1 truncate">${movieTitles}${more}</p>
                    </div>
                    <div class="flex items-center gap-2 flex-shrink-0">
                        <span class="text-xs text-gray-600">${timeStr}</span>
                        <button class="history-delete text-gray-700 hover:text-red-400 transition-colors text-xs" data-id="${entry.id}">&times;</button>
                    </div>
                </div>
            `;
            item.addEventListener('click', (e) => {
                if (e.target.classList.contains('history-delete')) return;
                showHistoryResults(entry);
            });
            list.appendChild(item);
        });

        // Add delete handlers
        list.querySelectorAll('.history-delete').forEach(btn => {
            btn.addEventListener('click', async (e) => {
                e.stopPropagation();
                const id = btn.dataset.id;
                await fetch(`${API}/api/history/${id}`, { method: 'DELETE' });
                loadHistory();
            });
        });

        // Show the toggle button if history is currently hidden
        if (document.getElementById('history-section').classList.contains('hidden')) {
            document.getElementById('history-toggle').classList.remove('hidden');
        }
    } catch { /* ignore */ }
}

function showHistoryResults(entry) {
    document.getElementById('mood-input').value = entry.mood;
    const data = { recommendations: entry.results, meta: entry.meta };
    renderResults(data);
    window.scrollTo({ top: 0, behavior: 'smooth' });
}

function toggleHistoryVisibility(show) {
    const section = document.getElementById('history-section');
    const toggle = document.getElementById('history-toggle');
    if (show) {
        section.classList.remove('hidden');
        toggle.classList.add('hidden');
    } else {
        section.classList.add('hidden');
        toggle.classList.remove('hidden');
    }
}

// --- Library Stats ---

async function loadStats() {
    try {
        const res = await fetch(`${API}/api/library/stats`);
        if (!res.ok) return;
        const stats = await res.json();
        document.getElementById('library-stats').textContent =
            `${stats.total_movies} movies in library${stats.last_sync ? ` · Last synced ${new Date(stats.last_sync).toLocaleString()}` : ''}`;
    } catch { /* ignore */ }
}

async function refreshLibrary() {
    document.getElementById('refresh-btn').textContent = 'Syncing...';
    try {
        await fetch(`${API}/api/library/sync`, { method: 'POST' });
        setTimeout(loadStats, 5000);
    } catch { /* ignore */ }
    setTimeout(() => {
        document.getElementById('refresh-btn').textContent = 'Refresh Library';
    }, 3000);
}

// --- Event Listeners ---

document.getElementById('login-form').addEventListener('submit', async (e) => {
    e.preventDefault();
    const errorEl = document.getElementById('login-error');
    errorEl.classList.add('hidden');
    try {
        await login(
            document.getElementById('login-username').value,
            document.getElementById('login-password').value
        );
    } catch (err) {
        errorEl.textContent = err.message;
        errorEl.classList.remove('hidden');
    }
});

document.getElementById('find-btn').addEventListener('click', findMovies);
document.getElementById('mood-input').addEventListener('keydown', (e) => {
    if (e.key === 'Enter') findMovies();
});
document.getElementById('logout-btn').addEventListener('click', logout);
document.getElementById('refresh-btn').addEventListener('click', refreshLibrary);
document.getElementById('toggle-history-btn').addEventListener('click', () => toggleHistoryVisibility(false));
document.getElementById('show-history-btn').addEventListener('click', () => {
    toggleHistoryVisibility(true);
    loadHistory();
});

// --- Init ---
checkAuth();