'use strict';

// go2rtc Player-Modi – Fallback-Reihenfolge: WebRTC → MSE → MJPEG
const MODE = 'webrtc,mse,mjpeg';

// ── Überwachungs-Parameter ───────────────────────────────────────────────────
const MONITOR_INTERVAL = 2000;   // ms zwischen Health-Checks
const DROP_WARN = 0.10;          // >10% verworfene Frames → gelb
const DROP_CRIT = 0.30;          // >30% verworfene Frames → rot
const OVERLOAD_TICKS = 3;        // so viele kritische Checks in Folge → Auto-Abschaltung

// ── Logging (Browser DevTools → Console → F12) ───────────────────────────────
const P = '[WebcamViewer]';
const log    = (c, m)    => console.log(`${P}[${c}] ${m}`);
const warn   = (c, m)    => console.warn(`${P}[${c}] ⚠ ${m}`);
const logErr = (c, m, e) => console.error(`${P}[${c}] ✗ ${m}`, e ?? '');

let GO2RTC_PORT = 1984;
const cameras = [];   // { id, box, infoEl, toggleBtn, active, last, badTicks, autoOff }

// ── Stream starten / stoppen (durch Erzeugen/Entfernen des Elements) ─────────
function startStream(cam) {
  if (cam.box.querySelector('video-stream')) return;   // läuft schon
  const wsUrl = `ws://${location.hostname}:${GO2RTC_PORT}/api/ws?src=${encodeURIComponent(cam.id)}`;
  log(cam.id, `Verbinde → ${wsUrl}`);

  const stream = document.createElement('video-stream');
  stream.mode = MODE;
  stream.addEventListener('playing', () => log(cam.id, '▶ Bild läuft'), true);
  stream.addEventListener('error', (e) => logErr(cam.id, 'Video-Fehler', e), true);
  stream.src = wsUrl;

  // Vor das Label einfügen, damit Overlays oben liegen
  cam.box.insertBefore(stream, cam.box.firstChild);
  cam.active = true;
  cam.last = null;
  cam.badTicks = 0;
  cam.toggleBtn.textContent = '⏸';
  cam.toggleBtn.title = 'Stream ausschalten';
}

function stopStream(cam, auto = false) {
  const el = cam.box.querySelector('video-stream');
  if (el) el.remove();                       // disconnectedCallback schließt WS/PeerConnection
  cam.active = false;
  cam.autoOff = auto;
  cam.toggleBtn.textContent = '▶';
  cam.toggleBtn.title = 'Stream einschalten';
  setInfo(cam, auto ? 'auto-aus (überlastet)' : 'aus', 'crit');
  log(cam.id, auto ? 'AUTO-abgeschaltet (Browser überlastet)' : 'manuell aus');
  if (auto) showNotice();
}

// ── Health-Anzeige ───────────────────────────────────────────────────────────
function setInfo(cam, text, cls) {
  cam.infoEl.textContent = text;
  cam.infoEl.className = 'cam-info ' + (cls ?? '');
}

// ── Monitor-Schleife: misst fps + verworfene Frames pro Kamera ───────────────
function monitorTick() {
  cameras.forEach(cam => {
    if (!cam.active) return;
    const video = cam.box.querySelector('video');
    if (!video || typeof video.getVideoPlaybackQuality !== 'function') {
      setInfo(cam, 'läuft', 'ok');
      return;
    }

    const q   = video.getVideoPlaybackQuality();
    const now = performance.now();
    const cur = { dropped: q.droppedVideoFrames, total: q.totalVideoFrames, t: now };

    // Beim ersten Tick (oder nach Neustart = Zähler zurückgesetzt) nur Baseline merken
    if (!cam.last || cur.total < cam.last.total) {
      cam.last = cur;
      setInfo(cam, 'misst…', 'ok');
      return;
    }

    const dTotal   = cur.total   - cam.last.total;
    const dDropped = cur.dropped - cam.last.dropped;
    const dSec     = (cur.t - cam.last.t) / 1000;
    cam.last = cur;

    if (dTotal <= 0) {                         // kein neuer Frame → evtl. Freeze
      setInfo(cam, '⏳ keine Frames', 'warn');
      cam.badTicks++;
    } else {
      const fps   = Math.round(dTotal / dSec);
      const ratio = dDropped / dTotal;
      const pct   = Math.round(ratio * 100);
      const cls   = ratio >= DROP_CRIT ? 'crit' : ratio >= DROP_WARN ? 'warn' : 'ok';
      setInfo(cam, `${fps} fps · ${pct}% drop`, cls);
      cam.badTicks = ratio >= DROP_CRIT ? cam.badTicks + 1 : 0;
    }

    // Auto-Schutz: anhaltende Überlast → diese Kamera abschalten
    if (cam.badTicks >= OVERLOAD_TICKS) {
      warn(cam.id, `überlastet (${cam.badTicks}× kritisch) → Auto-Abschaltung`);
      stopStream(cam, true);
    }
  });
}

// ── Hinweis-Banner bei Auto-Abschaltung ──────────────────────────────────────
function showNotice() {
  const off = cameras.filter(c => c.autoOff && !c.active).map(c => c.id);
  const bar = document.getElementById('notice');
  if (off.length === 0) { bar.style.display = 'none'; return; }
  bar.innerHTML = `⚠ Browser überlastet – automatisch deaktiviert: <b>${off.join(', ')}</b> `;
  const btn = document.createElement('button');
  btn.textContent = 'Wieder aktivieren';
  btn.onclick = () => {
    cameras.filter(c => c.autoOff && !c.active).forEach(c => { c.autoOff = false; startStream(c); });
    showNotice();
  };
  bar.appendChild(btn);
  bar.style.display = 'flex';
}

// ── Snapshot aller (auch abgeschalteter) Kameras ─────────────────────────────
function snapshotAll() {
  const ts = Date.now();
  const ids = cameras.map(c => c.id);
  log('snap', `Snapshot alle: ${ids.join(', ')}`);
  ids.forEach(id => {
    const a = document.createElement('a');
    a.href = `/api/snapshot/${id}`;
    a.download = `${id}_${ts}.jpg`;
    document.body.appendChild(a);
    a.click();
    a.remove();
  });
}

// ── Kamera-View aufbauen ─────────────────────────────────────────────────────
function buildCamera(camId, container) {
  const box = document.createElement('div');
  box.className = 'cam-box';

  const label = document.createElement('div');
  label.className = 'cam-label';
  label.textContent = camId;

  const info = document.createElement('div');
  info.className = 'cam-info';
  info.textContent = '…';

  const toggle = document.createElement('button');
  toggle.className = 'cam-toggle';

  const cam = { id: camId, box, infoEl: info, toggleBtn: toggle, active: false, last: null, badTicks: 0, autoOff: false };
  toggle.onclick = () => { cam.autoOff = false; cam.active ? stopStream(cam) : startStream(cam); showNotice(); };

  box.appendChild(label);
  box.appendChild(info);
  box.appendChild(toggle);
  container.appendChild(box);

  cameras.push(cam);
  startStream(cam);
}

// ── Init ─────────────────────────────────────────────────────────────────────
async function init() {
  log('init', 'Starte...');

  try {
    const d = await (await fetch('/config.json')).json();
    GO2RTC_PORT = d.go2rtcPort ?? 1984;
    log('init', `go2rtc WS-Port: ${GO2RTC_PORT}`);
  } catch (e) {
    warn('init', `/config.json nicht ladbar, nehme Port ${GO2RTC_PORT}`);
  }

  try {
    await customElements.whenDefined('video-stream');
    log('init', '<video-stream> definiert');
  } catch (e) {
    logErr('init', '<video-stream> nicht geladen – /video-stream.js erreichbar?', e);
    return;
  }

  const container  = document.getElementById('cameras');
  const statusText = document.getElementById('statusText');

  let camIds = [];
  try {
    const r = await fetch('/api/snapshot');
    log('init', `/api/snapshot → HTTP ${r.status}`);
    if (r.ok) camIds = ((await r.json()).cameras ?? []).map(c => c.id);
    log('init', `Kameras: ${camIds.join(', ') || '(keine)'}`);
  } catch (e) {
    logErr('init', '/api/snapshot Fehler – Fallback', e);
  }
  if (camIds.length === 0) { warn('init', 'Fallback cam0, cam1'); camIds = ['cam0', 'cam1']; }

  const snapBtn = document.getElementById('snapAllBtn');
  if (snapBtn) { snapBtn.onclick = snapshotAll; snapBtn.disabled = false; }

  camIds.forEach(id => buildCamera(id, container));
  statusText.textContent = `${camIds.length} Kamera${camIds.length !== 1 ? 's' : ''} · WebRTC`;

  setInterval(monitorTick, MONITOR_INTERVAL);   // Health-Überwachung starten
  log('init', 'Fertig – Überwachung aktiv');
}

init();