const CACHE_NAME = 'gridtv-v2';

// Static assets cached during installation.
const STATIC_ASSETS = [
  '/',
  '/index.php',
  '/manifest.json',
  '/assets/fonts/fonts.css',
  '/assets/icon-192.png',
  '/assets/icon-512.png',
  '/assets/vendor/hls.min.js'
];

// Install: cache the static assets.
self.addEventListener('install', e => {
  e.waitUntil(
    caches.open(CACHE_NAME)
      .then(cache => cache.addAll(STATIC_ASSETS))
      .then(() => self.skipWaiting())
  );
});

// Activate: remove outdated caches.
self.addEventListener('activate', e => {
  e.waitUntil(
    caches.keys().then(keys =>
      Promise.all(keys.filter(k => k !== CACHE_NAME).map(k => caches.delete(k)))
    ).then(() => self.clients.claim())
  );
});

// Fetch: choose a caching strategy based on resource type.
self.addEventListener('fetch', e => {
  const url = new URL(e.request.url);

  // EPG/M3U feeds, the GitHub API, and version.json stay network-only.
  if (
    url.pathname.includes('xmltv') ||
    url.pathname.includes('.m3u') ||
    url.hostname === 'api.github.com' ||
    url.pathname.includes('proxy.php') ||
    url.pathname.endsWith('version.json')
  ) {
    return;
  }

  // Static assets use a cache-first strategy.
  if (
    e.request.destination === 'style' ||
    e.request.destination === 'script' ||
    e.request.destination === 'font' ||
    e.request.destination === 'image' ||
    url.pathname.endsWith('.json') ||
    url.pathname.endsWith('.css') ||
    url.pathname.endsWith('.js')
  ) {
    e.respondWith(
      caches.match(e.request).then(cached => cached || fetch(e.request).then(res => {
        const clone = res.clone();
        caches.open(CACHE_NAME).then(cache => cache.put(e.request, clone));
        return res;
      }))
    );
    return;
  }

  // PHP pages use network-first with cache fallback.
  e.respondWith(
    fetch(e.request)
      .then(res => {
        const clone = res.clone();
        caches.open(CACHE_NAME).then(cache => cache.put(e.request, clone));
        return res;
      })
      .catch(() => caches.match(e.request))
  );
});

self.addEventListener('notificationclick', e => {
  const url = e.notification?.data?.url || '/index.php';
  e.notification.close();
  e.waitUntil(
    clients.matchAll({ type: 'window', includeUncontrolled: true }).then(windowClients => {
      for (const client of windowClients) {
        if ('focus' in client) {
          client.navigate(url);
          return client.focus();
        }
      }
      if (clients.openWindow) return clients.openWindow(url);
      return undefined;
    })
  );
});