// NextNVR v0.1.0 — Single Page Application
// Tabbed UI: Live Wall (4×2 grid + focus), Playback browser, Settings/Onboarding

const API = '/api';

// ── App State ──
let cameras = [];
let config = null;

// ── Init ──
document.addEventListener('DOMContentLoaded', async () => {
    setupTabs();
    await loadStatus();
    await loadCameras();
    renderLiveGrid();
    renderPlaybackCameras();
    renderCameraCards();
});

// ── Tabs ──
function setupTabs() {
    document.querySelectorAll('.tab').forEach(btn => {
        btn.addEventListener('click', () => {
            document.querySelectorAll('.tab').forEach(b => b.classList.remove('active'));
            document.querySelectorAll('.tab-panel').forEach(p => p.classList.remove('active'));
            btn.classList.add('active');
            document.getElementById('tab-' + btn.dataset.tab).classList.add('active');
        });
    });
}

// ── Status ──
async function loadStatus() {
    try {
        const r = await fetch(API + '/status');
        const j = await r.json();
        const dot = document.getElementById('status-dot');
        dot.className = 'status ' + (j.success ? 'online' : 'offline');
    } catch(e) {
        document.getElementById('status-dot').className = 'status offline';
    }
}

// ── Cameras ──
async function loadCameras() {
    try {
        const r = await fetch(API + '/cameras');
        const j = await r.json();
        if (j.success) cameras = j.data;
    } catch(e) { cameras = []; }
}

// ── Live Grid ──
function renderLiveGrid() {
    const grid = document.getElementById('grid');
    grid.innerHTML = '';
    for (let i = 0; i < 8; i++) {
        const cam = cameras[i];
        const tile = document.createElement('div');
        tile.className = 'grid-tile' + (cam && cam.enabled ? '' : ' offline');
        tile.dataset.camId = cam ? cam.id : '';

        if (cam) {
            tile.innerHTML = `
                <span class="tile-status ${cam.online ? 'online' : 'offline'}"></span>
                <span class="tile-label">${cam.name}</span>
            `;
            tile.addEventListener('click', () => openFocus(cam));
        } else {
            tile.innerHTML = '<span class="tile-placeholder">No Camera</span>';
        }
        grid.appendChild(tile);
    }
}

// ── Focus Overlay ──
let focusIdx = -1;
function openFocus(cam) {
    focusIdx = cameras.indexOf(cam);
    const overlay = document.getElementById('focus-overlay');
    overlay.classList.remove('hidden');
    updateFocus();
    renderThumbs();
}
function updateFocus() {
    if (focusIdx < 0 || focusIdx >= cameras.length) return;
    const cam = cameras[focusIdx];
    document.getElementById('focus-title').textContent = cam.name;
    document.getElementById('focus-time').textContent = new Date().toLocaleTimeString() + ' live';
    // TODO: M3 — connect to go2rtc WebRTC stream
    const vid = document.getElementById('focus-video');
    vid.src = '';
    vid.poster = ''; // placeholder until go2rtc is wired up
}
function renderThumbs() {
    const strip = document.getElementById('focus-thumbs');
    strip.innerHTML = '';
    cameras.forEach((cam, i) => {
        const thumb = document.createElement('div');
        thumb.className = 'thumb' + (i === focusIdx ? ' active' : '');
        thumb.textContent = cam.name;
        thumb.title = cam.name;
        thumb.addEventListener('click', () => { focusIdx = i; updateFocus(); renderThumbs(); });
        strip.appendChild(thumb);
    });
}
document.getElementById('focus-close').addEventListener('click', () => {
    document.getElementById('focus-overlay').classList.add('hidden');
});
document.getElementById('focus-prev').addEventListener('click', () => {
    if (focusIdx > 0) { focusIdx--; updateFocus(); renderThumbs(); }
});
document.getElementById('focus-next').addEventListener('click', () => {
    if (focusIdx < cameras.length - 1) { focusIdx++; updateFocus(); renderThumbs(); }
});
document.addEventListener('keydown', e => {
    if (document.getElementById('focus-overlay').classList.contains('hidden')) return;
    if (e.key === 'Escape') document.getElementById('focus-overlay').classList.add('hidden');
    if (e.key === 'ArrowLeft' && focusIdx > 0) { focusIdx--; updateFocus(); renderThumbs(); }
    if (e.key === 'ArrowRight' && focusIdx < cameras.length - 1) { focusIdx++; updateFocus(); renderThumbs(); }
});

// ── Playback ──
function renderPlaybackCameras() {
    const sel = document.getElementById('pb-camera');
    sel.innerHTML = '<option value="">— Select Camera —</option>';
    cameras.forEach(c => {
        sel.innerHTML += `<option value="${c.id}">${c.name}</option>`;
    });
}
document.getElementById('pb-load').addEventListener('click', async () => {
    const cam = document.getElementById('pb-camera').value;
    const date = document.getElementById('pb-date').value;
    if (!cam || !date) return;
    try {
        const r = await fetch(API + '/recordings?cam=' + cam + '&date=' + date);
        const j = await r.json();
        renderClips(j.data || []);
    } catch(e) { renderClips([]); }
});
function renderClips(clips) {
    const grid = document.getElementById('pb-clips');
    if (clips.length === 0) { grid.innerHTML = '<p style="color:var(--text-muted)">No recordings found.</p>'; return; }
    grid.innerHTML = clips.map(c => `
        <div class="clip-card" onclick="playClip('${c.path}')">
            <div>🎬 ${c.name}</div>
            <div class="clip-time">${c.time}</div>
            <div class="clip-size">${formatSize(c.size)}</div>
        </div>
    `).join('');
}
function playClip(path) {
    document.getElementById('pb-player').classList.remove('hidden');
    document.getElementById('pb-video').src = '/recordings/' + path;
}
document.getElementById('pb-close').addEventListener('click', () => {
    document.getElementById('pb-player').classList.add('hidden');
    document.getElementById('pb-video').src = '';
});

// ── Settings / Onboarding ──
async function renderCameraCards() {
    const container = document.getElementById('camera-cards');
    if (cameras.length === 0) {
        container.innerHTML = `
            <div style="grid-column:1/-1;text-align:center;padding:40px;color:var(--text-muted)">
                <p style="font-size:18px">🎥 Welcome to NextNVR</p>
                <p style="margin-top:8px">No cameras configured yet. Scan your network to get started.</p>
                <button class="btn-primary" style="margin-top:16px" onclick="document.getElementById('btn-scan').click()">
                    🔍 Scan Network (ONVIF)
                </button>
            </div>`;
        return;
    }
    container.innerHTML = cameras.map(c => `
        <div class="camera-card" data-id="${c.id}">
            <h3>📷 ${c.name || 'Unnamed'} <span style="font-size:11px;color:var(--text-muted)">${c.ip}</span></h3>
            <label>Name <input type="text" value="${escAttr(c.name)}" data-field="name"></label>
            <label>Description <textarea data-field="description">${escHtml(c.description)}</textarea></label>
            <label>RTSP Main <input type="text" value="${escAttr(c.rtsp_main)}" data-field="rtsp_main"></label>
            <label>RTSP Sub <input type="text" value="${escAttr(c.rtsp_sub)}" data-field="rtsp_sub"></label>
            <label>Username <input type="text" value="${escAttr(c.username)}" data-field="username"></label>
            <label>Password <input type="password" value="${escAttr(c.password)}" data-field="password"></label>
            <div class="row">
                <label>Enabled <input type="checkbox" ${c.enabled ? 'checked' : ''} data-field="enabled" style="width:auto"></label>
                <label>Record <input type="checkbox" ${c.record ? 'checked' : ''} data-field="record" style="width:auto"></label>
            </div>
        </div>
    `).join('');
}

// ── Settings: Scan ──
document.getElementById('btn-scan').addEventListener('click', async () => {
    const btn = document.getElementById('btn-scan');
    const status = document.getElementById('settings-status');
    btn.disabled = true;
    btn.textContent = '⏳ Scanning...';
    status.textContent = 'Probing 192.168.1.201–209...';
    try {
        const r = await fetch(API + '/scan', { method: 'POST' });
        const j = await r.json();
        if (j.success) {
            status.textContent = `Found ${j.data.length} devices. Fill in names and save.`;
            // Pre-fill camera cards with discovered data.
            cameras = j.data.map((d, i) => ({
                id: 'cam_' + d.ip.split('.').pop(),
                name: d.found ? d.manufacturer + ' ' + d.model : 'Camera ' + (201 + i),
                ip: d.ip,
                username: 'admin', password: '',
                onvif_port: 80,
                rtsp_main: d.rtsp_main || '',
                rtsp_sub: d.rtsp_sub || '',
                description: '',
                enabled: true, record: true,
                online: d.found
            }));
            renderCameraCards();
            renderLiveGrid();
            renderPlaybackCameras();
        }
    } catch(e) {
        status.textContent = 'Scan failed: ' + e.message;
    }
    btn.disabled = false;
    btn.textContent = '🔍 Scan Network (ONVIF)';
});

// ── Settings: Save ──
document.getElementById('btn-save').addEventListener('click', async () => {
    const status = document.getElementById('settings-status');
    // Collect camera data from DOM.
    const cards = document.querySelectorAll('.camera-card');
    const updatedCameras = [];
    cards.forEach(card => {
        const c = {};
        card.querySelectorAll('[data-field]').forEach(el => {
            const field = el.dataset.field;
            if (el.type === 'checkbox') c[field] = el.checked;
            else c[field] = el.value;
        });
        updatedCameras.push(c);
    });

    try {
        // Fetch current config, then post updated version.
        const cr = await fetch(API + '/config');
        const cj = await cr.json();
        const cfg = cj.data || {};
        cfg.cameras = updatedCameras;

        const r = await fetch(API + '/config', {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify(cfg)
        });
        const j = await r.json();
        if (j.success) {
            status.textContent = '✅ Configuration saved! Restart may be required.';
            status.style.color = 'var(--green)';
        } else {
            status.textContent = '❌ Save failed: ' + j.error;
            status.style.color = 'var(--red)';
        }
    } catch(e) {
        status.textContent = '❌ Error: ' + e.message;
        status.style.color = 'var(--red)';
    }
});

// ── Helpers ──
function escAttr(s) { return (s || '').replace(/&/g,'&amp;').replace(/"/g,'&quot;'); }
function escHtml(s) { return (s || '').replace(/&/g,'&amp;').replace(/</g,'&lt;').replace(/>/g,'&gt;'); }
function formatSize(bytes) {
    if (!bytes || bytes === 0) return '0 B';
    const u = ['B','KB','MB','GB'];
    const i = Math.floor(Math.log(bytes) / Math.log(1024));
    return (bytes / Math.pow(1024, i)).toFixed(1) + ' ' + u[i];
}