const CACHE_NAME = 'base-tracker-cache-v1';
const APP_SHELL = ['/'];

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

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

self.addEventListener('fetch', (event) => {
  if (event.request.method !== 'GET') {
    return;
  }

  if (event.request.mode === 'navigate') {
    event.respondWith(
      fetch(event.request).catch(async () => {
        const offlineFallback = await caches.match('/');
        return offlineFallback ?? Response.error();
      })
    );
    return;
  }

  if (!event.request.url.startsWith(self.location.origin)) {
    return;
  }

  event.respondWith(
    caches.match(event.request).then((cachedResponse) => {
      const networkFetch = fetch(event.request)
        .then((networkResponse) => {
          if (
            networkResponse &&
            networkResponse.status === 200 &&
            networkResponse.type === 'basic' &&
            !networkResponse.headers.get('Cache-Control')?.includes('no-store')
          ) {
            const responseClone = networkResponse.clone();
            caches.open(CACHE_NAME).then((cache) => cache.put(event.request, responseClone));
          }
          return networkResponse;
        })
        .catch(() => cachedResponse);

      return cachedResponse || networkFetch;
    })
  );
});

self.addEventListener('message', (event) => {
  if (event.data === 'skipWaiting') {
    self.skipWaiting();
  }
});