document.addEventListener("DOMContentLoaded", async () => {
    const username = localStorage.getItem('username');
    const userKey = localStorage.getItem('userKey');

    if (!username || !userKey) {
        window.location.href = '/';
        return;
    }

    try {
        const response = await fetch('/validate', {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify({ username, key: userKey })
        });
        if (!response.ok) {
            localStorage.clear();
            window.location.href = '/';
            return;
        }
    } catch (err) {
        console.error('Validation failed:', err);
        localStorage.clear();
        window.location.href = '/';
        return;
    }

    function escapeHtml(text) {
        if (!text) return text;
        return text
            .replace(/&/g, "&")
            .replace(/</g, "&lt;")
            .replace(/>/g, "&gt;")
            .replace(/"/g, "&quot;")
            .replace(/'/g, "&#039;");
    }

    // User header bar
    const userInfoEl = document.getElementById('user-info');

    const logoutBtn = document.createElement('button');
    logoutBtn.textContent = 'Logout';
    logoutBtn.className = 'logout-btn';
    logoutBtn.onclick = async () => {
        if (confirm("Are you sure you want to logout? This releases your username.")) {
            try {
                await fetch('/logout', {
                    method: 'POST',
                    headers: { 'Content-Type': 'application/json' },
                    body: JSON.stringify({ username, key: userKey })
                });
            } catch (e) {
                console.error("Logout request failed:", e);
            }
            localStorage.clear();
            sessionStorage.clear();
            window.location.href = '/';
        }
    };

    const userSpan = document.createElement('span');
    userSpan.innerHTML = `Logged in as: <strong>${escapeHtml(username)}</strong>`;

    userInfoEl.append(logoutBtn, userSpan);

    const activeRoomsContainer = document.getElementById('active-rooms-container');
    const statsBadge = document.getElementById('stats-badge');

    // Modal elements
    const joinModal = document.getElementById('join-modal');
    const joinModalForm = document.getElementById('join-modal-form');
    const modalRoomTitle = document.getElementById('modal-room-title');
    const modalPasswordInput = document.getElementById('modal-room-password');
    const modalCancelBtn = document.getElementById('modal-cancel-btn');

    let pendingJoinRoom = null;
    let pendingJoinHasWP = false;

    function openJoinModal(roomName, hasWP) {
        pendingJoinRoom = roomName;
        pendingJoinHasWP = hasWP;
        modalRoomTitle.textContent = `🔒 Join "${roomName}"`;
        modalPasswordInput.value = '';
        joinModal.classList.remove('hidden');
        modalPasswordInput.focus();
    }

    function closeJoinModal() {
        joinModal.classList.add('hidden');
        pendingJoinRoom = null;
    }

    if (modalCancelBtn) {
        modalCancelBtn.addEventListener('click', closeJoinModal);
    }

    if (joinModalForm) {
        joinModalForm.addEventListener('submit', async (e) => {
            e.preventDefault();
            const password = modalPasswordInput.value.trim();
            if (!password || !pendingJoinRoom) return;

            const joinBtn = document.getElementById('modal-join-btn');
            if (joinBtn) joinBtn.disabled = true;

            try {
                const res = await fetch('/rooms/join', {
                    method: 'POST',
                    headers: { 'Content-Type': 'application/json' },
                    body: JSON.stringify({
                        room: pendingJoinRoom,
                        password: password,
                        username: username,
                        key: userKey
                    })
                });

                if (joinBtn) joinBtn.disabled = false;

                if (!res.ok) {
                    const err = await res.json().catch(() => ({}));
                    alert(err.error || 'Incorrect room password.');
                    modalPasswordInput.value = '';
                    modalPasswordInput.focus();
                    return;
                }

                // Success
                sessionStorage.setItem(`room_password_${pendingJoinRoom}`, password);
                const wpParam = pendingJoinHasWP ? '&watchparty=1' : '';
                window.location.href = `/chat.html?room=${encodeURIComponent(pendingJoinRoom)}${wpParam}`;
            } catch (err) {
                if (joinBtn) joinBtn.disabled = false;
                console.error('Join error:', err);
                alert('Network error while joining room.');
            }
        });
    }

    async function loadActiveRooms() {
        try {
            const res = await fetch('/rooms');
            if (!res.ok) throw new Error('Failed to fetch rooms');

            const data = await res.json();
            const rooms = data.active_rooms || [];
            const uniqueUsers = data.unique_users || 0;

            statsBadge.innerHTML = `🟢 Active Rooms: <strong>${rooms.length}</strong> &nbsp;•&nbsp; 👥 Online Users: <strong>${uniqueUsers}</strong>`;

            activeRoomsContainer.innerHTML = '';

            if (rooms.length === 0) {
                activeRoomsContainer.innerHTML = `
                    <div class="empty-state">
                        No active rooms right now.<br>Create an on-demand room below to start chatting!
                    </div>
                `;
                return;
            }

            rooms.forEach(room => {
                const card = document.createElement('div');
                card.className = 'room-card';

                const left = document.createElement('div');
                left.className = 'room-info-left';

                const titleLink = document.createElement('span');
                titleLink.className = 'room-title-link';
                titleLink.textContent = room.name;

                const badges = document.createElement('div');
                badges.className = 'room-badges';
                badges.innerHTML = `
                    <span>👥 ${room.users} user${room.users === 1 ? '' : 's'}</span>
                    <span class="badge-encrypted">🔒 Encrypted</span>
                    ${room.has_watchparty ? '<span class="badge-watchparty">🎬 Watch Party</span>' : ''}
                `;

                left.append(titleLink, badges);

                const joinBtn = document.createElement('button');
                joinBtn.textContent = 'Join Room';

                const handleJoin = () => {
                    const storedPass = sessionStorage.getItem(`room_password_${room.name}`);
                    if (storedPass) {
                        const wpParam = room.has_watchparty ? '&watchparty=1' : '';
                        window.location.href = `/chat.html?room=${encodeURIComponent(room.name)}${wpParam}`;
                    } else {
                        openJoinModal(room.name, room.has_watchparty);
                    }
                };

                titleLink.addEventListener('click', handleJoin);
                joinBtn.addEventListener('click', handleJoin);

                card.append(left, joinBtn);
                activeRoomsContainer.appendChild(card);
            });
        } catch (err) {
            console.error('Failed to load active rooms:', err);
            statsBadge.textContent = 'Failed to load rooms';
        }
    }

    await loadActiveRooms();
    setInterval(loadActiveRooms, 3000); // Poll active rooms every 3 seconds

    // On-Demand Room Creation Form
    const createRoomForm = document.getElementById('create-room-form');
    if (createRoomForm) {
        createRoomForm.addEventListener('submit', async (e) => {
            e.preventDefault();
            const roomName = document.getElementById('new-room-name').value.trim();
            const password = document.getElementById('new-room-password').value.trim();
            const isWatchParty = document.getElementById('new-room-watchparty').checked;

            if (!roomName || !password) {
                alert('Please enter both a room name and password.');
                return;
            }

            const createBtn = document.getElementById('create-room-btn');
            createBtn.disabled = true;

            try {
                const res = await fetch('/rooms/join', {
                    method: 'POST',
                    headers: { 'Content-Type': 'application/json' },
                    body: JSON.stringify({
                        room: roomName,
                        password: password,
                        username: username,
                        key: userKey
                    })
                });

                createBtn.disabled = false;

                if (!res.ok) {
                    const err = await res.json().catch(() => ({}));
                    alert(err.error || 'Failed to create room.');
                    return;
                }

                // Store password in session
                sessionStorage.setItem(`room_password_${roomName}`, password);
                const wpParam = isWatchParty ? '&watchparty=1' : '';
                window.location.href = `/chat.html?room=${encodeURIComponent(roomName)}${wpParam}`;
            } catch (err) {
                createBtn.disabled = false;
                console.error('Room creation error:', err);
                alert('Network error while creating room.');
            }
        });
    }
});