const CACHE = 'hamham-public-v1';
async function savePage(address) {
  const url = new URL(address, self.location.origin);
  if (url.origin !== self.location.origin) return;
  const match = /^\/rezepte\/([a-f0-9-]{36})(?:\/kochen)?$/.exec(url.pathname);
  if (match) {
    const recipe = await fetch(`/api/recipes/${match[1]}`).then((r) => (r.ok ? r.json() : null));
    if (!recipe?.published) return;
  } else if (!['/', '/favoriten', '/einkaufsliste'].includes(url.pathname)) return;
  const response = await fetch(url.href, { headers: { Accept: 'text/html' } });
  if (!response.ok || !response.headers.get('content-type')?.includes('text/html')) return;
  const cache = await caches.open(CACHE),
    html = await response.clone().text();
  await cache.put(url.href, response);
  const paths = [
    ...new Set(
      Array.from(
        html.matchAll(/(?:src|href)="(\/(?:_next\/static\/|images\/|icons\/|media\/)[^"<>]+)"/g),
        (m) => m[1].replaceAll('&amp;', '&'),
      ),
    ),
  ];
  await Promise.all(
    paths.map(async (path) => {
      try {
        const r = await fetch(path);
        if (r.ok) await cache.put(path, r);
      } catch {}
    }),
  );
}
self.addEventListener('message', (event) => {
  if (event.data?.type === 'CACHE_PAGE' && typeof event.data.url === 'string')
    event.waitUntil(savePage(event.data.url).catch(() => {}));
});
self.addEventListener('install', (event) => {
  event.waitUntil(
    caches.open(CACHE).then((cache) => cache.addAll(['/offline.html', '/icons/icon-192.png'])),
  );
  self.skipWaiting();
});
self.addEventListener('activate', (event) => {
  event.waitUntil(
    caches
      .keys()
      .then((keys) => Promise.all(keys.filter((k) => k !== CACHE).map((k) => caches.delete(k)))),
  );
  self.clients.claim();
});
self.addEventListener('fetch', (event) => {
  const req = event.request,
    url = new URL(req.url);
  if (
    req.method !== 'GET' ||
    url.origin !== self.location.origin ||
    url.pathname.startsWith('/admin') ||
    url.pathname.startsWith('/api') ||
    url.searchParams.has('_rsc') ||
    req.headers.get('rsc')
  )
    return;
  const asset = /^\/(?:_next\/static\/|images\/|icons\/|media\/)/.test(url.pathname);
  const recipe = /^\/rezepte\/([a-f0-9-]{36})(?:\/kochen)?$/.exec(url.pathname);
  if (!asset && req.mode !== 'navigate') return;
  event.respondWith(
    (async () => {
      const cache = await caches.open(CACHE);
      if (asset) {
        const cached = await cache.match(req);
        if (cached) return cached;
      }
      try {
        const response = await fetch(req);
        if (response.ok && asset) await cache.put(req, response.clone());
        if (response.ok && recipe) {
          // Never persist a draft or an administrator page. Only published recipes.
          const data = await fetch(`/api/recipes/${recipe[1]}`)
            .then((r) => (r.ok ? r.json() : null))
            .catch(() => null);
          if (data?.published) await cache.put(req, response.clone());
          else await cache.delete(req);
        }
        return response;
      } catch {
        const saved =
          (await cache.match(req)) ??
          (req.mode === 'navigate' ? await cache.match(req, { ignoreSearch: true }) : null);
        if (saved) return saved;
        if (req.mode === 'navigate') return await cache.match('/offline.html');
        return new Response('', { status: 503 });
      }
    })(),
  );
});