// ── Firebase Messaging (background push for Android PWA) ──────────────────────
// Fill in the values below from Firebase Console → Project Settings → General → Your apps
// Leave apiKey as '__FIREBASE_API_KEY__' if not using FCM (push will be disabled).
importScripts('https://www.gstatic.com/firebasejs/10.14.1/firebase-app-compat.js');
importScripts('https://www.gstatic.com/firebasejs/10.14.1/firebase-messaging-compat.js');

const FIREBASE_CONFIG = {
  apiKey: "AIzaSyDx191unzXFT4WA1OvkdbrIY_c57kgruAU",
  authDomain: "rosterchirp-push.firebaseapp.com",
  projectId: "rosterchirp-push",
  storageBucket: "rosterchirp-push.firebasestorage.app",
  messagingSenderId: "126479377334",
  appId: "1:126479377334:web:280abdd135cf7e0c50d717"
};

// Only initialise Firebase if the config has been filled in
let messaging = null;
if (FIREBASE_CONFIG.apiKey !== '__FIREBASE_API_KEY__') {
  firebase.initializeApp(FIREBASE_CONFIG);
  messaging = firebase.messaging();
}

// ── Cache ─────────────────────────────────────────────────────────────────────
const CACHE_NAME = 'rosterchirp-v1';
const STATIC_ASSETS = ['/'];

self.addEventListener('install', (event) => {
  event.waitUntil(
    caches.open(CACHE_NAME).then((cache) => cache.addAll(STATIC_ASSETS))
  );
  self.skipWaiting();
});

self.addEventListener('activate', (event) => {
  event.waitUntil(
    caches.keys().then((keys) =>
      Promise.all(keys.filter(k => k !== CACHE_NAME).map(k => caches.delete(k)))
    )
  );
  self.clients.claim();
});

self.addEventListener('fetch', (event) => {
  const url = event.request.url;
  if (url.includes('/api/') || url.includes('/socket.io/') || url.includes('/manifest.json')) {
    return;
  }
  event.respondWith(
    fetch(event.request).catch(() => caches.match(event.request))
  );
});

// ── Badge counter ─────────────────────────────────────────────────────────────
let badgeCount = 0;

function showRosterChirpNotification(data) {
  badgeCount++;
  if (self.navigator?.setAppBadge) self.navigator.setAppBadge(badgeCount).catch(() => {});

  return self.registration.showNotification(data.title || 'New Message', {
    body:    data.body || '',
    icon:    '/icons/icon-192.png',
    badge:   '/icons/icon-192-maskable.png',
    data:    { url: data.url || '/' },
    tag:     data.groupId ? `rosterchirp-group-${data.groupId}` : 'rosterchirp-message',
    renotify: true,
  });
}

// ── FCM background messages ───────────────────────────────────────────────────
if (messaging) {
  messaging.onBackgroundMessage((payload) => {
    return showRosterChirpNotification(payload.data || {});
  });
}

// ── Notification click ────────────────────────────────────────────────────────
self.addEventListener('notificationclick', (event) => {
  event.notification.close();
  badgeCount = 0;
  if (self.navigator?.clearAppBadge) self.navigator.clearAppBadge().catch(() => {});
  event.waitUntil(
    clients.matchAll({ type: 'window', includeUncontrolled: true }).then((clientList) => {
      const url = event.notification.data?.url || '/';
      for (const client of clientList) {
        if (client.url.includes(self.location.origin) && 'focus' in client) {
          client.focus();
          return;
        }
      }
      return clients.openWindow(url);
    })
  );
});

// ── Badge control messages from main thread ───────────────────────────────────
self.addEventListener('message', (event) => {
  if (event.data?.type === 'CLEAR_BADGE') {
    badgeCount = 0;
    if (self.navigator?.clearAppBadge) self.navigator.clearAppBadge().catch(() => {});
  }
  if (event.data?.type === 'SET_BADGE') {
    badgeCount = event.data.count || 0;
    if (self.navigator?.setAppBadge) {
      if (badgeCount > 0) {
        self.navigator.setAppBadge(badgeCount).catch(() => {});
      } else {
        self.navigator.clearAppBadge().catch(() => {});
      }
    }
  }
});