const CACHE_NAME = "multica-v1";

// App shell resources to precache
const PRECACHE_URLS = ["/~offline"];

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

self.addEventListener("activate", (event) => {
  // Clean up old caches
  event.waitUntil(
    caches.keys().then((names) =>
      Promise.all(
        names
          .filter((name) => name !== CACHE_NAME)
          .map((name) => caches.delete(name))
      )
    )
  );
  self.clients.claim();
});

self.addEventListener("fetch", (event) => {
  // Only handle navigation requests (HTML pages)
  if (event.request.mode === "navigate") {
    event.respondWith(
      fetch(event.request).catch(() =>
        caches.match("/~offline").then(
          (response) =>
            response ||
            new Response("Offline", { status: 503, statusText: "Offline" })
        )
      )
    );
  }
});