const CACHE_NAME = 'pm-pwa-shell-v1';
const OFFLINE_URL = '/offline.html';

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

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

self.addEventListener('fetch', (event) => {
  const url = new URL(event.request.url);

  if (url.pathname.startsWith('/api/')) {
    return;
  }

  if (event.request.mode === 'navigate') {
    event.respondWith(
      fetch(event.request).catch(() => caches.match(OFFLINE_URL))
    );
  }
});