const CACHE = "cet6-shell-v2";
const APP_SHELL = ["/", "/manifest.webmanifest", "/favicon.svg", "/icon-192.png", "/icon-512.png"];
self.addEventListener("install", event => event.waitUntil(caches.open(CACHE).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).map(key => caches.delete(key)))).then(() => self.clients.claim())
));
self.addEventListener("fetch", event => {
  const request = event.request;
  if (request.method !== "GET" || new URL(request.url).origin !== location.origin) return;
  if (request.url.includes("/api/")) return;
  event.respondWith(fetch(request).then(response => {
    if (response.ok && new URL(request.url).pathname.startsWith("/_next/")) {
      const copy = response.clone(); caches.open(CACHE).then(cache => cache.put(request, copy));
    }
    return response;
  }).catch(() => caches.match(request).then(found => found || caches.match("/"))));
});