const CACHE_NAME = 'teamchat-v2';
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))
  );
});

// Track badge count in SW
let badgeCount = 0;

self.addEventListener('push', (event) => {
  if (!event.data) return;
  const data = event.data.json();

  badgeCount++;

  // Update app badge (supported on Android Chrome and some desktop)
  if (navigator.setAppBadge) {
    navigator.setAppBadge(badgeCount).catch(() => {});
  }

  event.waitUntil(
    self.registration.showNotification(data.title || 'New Message', {
      body: data.body || '',
      icon: '/icons/icon-192.png',
      badge: '/icons/icon-192.png',
      data: { url: data.url || '/' },
      tag: 'teamchat-message',       // replaces previous notification instead of stacking
      renotify: true,                 // still vibrate/sound even if replacing
    })
  );
});

self.addEventListener('notificationclick', (event) => {
  event.notification.close();
  badgeCount = 0;
  if (navigator.clearAppBadge) 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);
    })
  );
});

// Clear badge when user opens the app
self.addEventListener('message', (event) => {
  if (event.data?.type === 'CLEAR_BADGE') {
    badgeCount = 0;
    if (navigator.clearAppBadge) navigator.clearAppBadge().catch(() => {});
  }
});