/* Media Cluster Ops — lightweight PWA service worker */
const CACHE = "mc-ops-v1";
const PRECACHE = ["/", "/dashboard", "/manifest.webmanifest", "/icons/icon.svg"];

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

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

self.addEventListener("fetch", (event) => {
  const req = event.request;
  if (req.method !== "GET") return;

  const url = new URL(req.url);
  if (url.origin !== self.location.origin) return;

  // Never cache API / auth — always network
  if (url.pathname.startsWith("/api/")) return;

  // Navigations: network-first, fallback cache
  if (req.mode === "navigate") {
    event.respondWith(
      fetch(req)
        .then((res) => {
          const copy = res.clone();
          caches.open(CACHE).then((c) => c.put(req, copy));
          return res;
        })
        .catch(() => caches.match(req).then((r) => r || caches.match("/dashboard")))
    );
    return;
  }

  // Static assets: stale-while-revalidate
  event.respondWith(
    caches.match(req).then((cached) => {
      const network = fetch(req)
        .then((res) => {
          if (res.ok) {
            const copy = res.clone();
            caches.open(CACHE).then((c) => c.put(req, copy));
          }
          return res;
        })
        .catch(() => cached);
      return cached || network;
    })
  );
});