/* Minimaler Service-Worker: App-Shell-Cache für Offline-Hinweis. */
const CACHE = "grotti-shell-v1";
const SHELL = ["/", "/static/grotti.css?v=54", "/static/api.js?v=28", "/static/ui.js?v=2"];

self.addEventListener("install", (event) => {
  event.waitUntil(caches.open(CACHE).then((c) => c.addAll(SHELL).catch(() => undefined)));
  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;
  if (req.method !== "GET") return;
  const url = new URL(req.url);
  if (url.pathname.startsWith("/api/")) return;
  event.respondWith(
    fetch(req).catch(() => caches.match(req).then((hit) => hit || caches.match("/")))
  );
});