const CACHE_NAME = "nowhatever-v1";

const PRECACHE_URLS = ["/", "/offline"];

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

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

self.addEventListener("fetch", (event) => {
  const { request } = event;

  if (request.method !== "GET") return;

  const url = new URL(request.url);

  // API calls: network-only
  if (url.pathname.startsWith("/api/")) return;

  // Static assets (_next/static, icons, fonts): cache-first
  if (
    url.pathname.startsWith("/_next/static/") ||
    url.pathname.match(/\.(png|jpg|svg|ico|woff2?)$/)
  ) {
    event.respondWith(
      caches.match(request).then(
        (cached) =>
          cached ||
          fetch(request).then((response) => {
            const clone = response.clone();
            caches.open(CACHE_NAME).then((cache) => cache.put(request, clone));
            return response;
          })
      )
    );
    return;
  }

  // HTML pages: network-first, fallback to cache, then offline page
  event.respondWith(
    fetch(request)
      .then((response) => {
        const clone = response.clone();
        caches.open(CACHE_NAME).then((cache) => cache.put(request, clone));
        return response;
      })
      .catch(() => caches.match(request).then((cached) => cached || caches.match("/offline")))
  );
});