const CACHE_NAME = "apicore-shell-v2";

self.addEventListener("install", () => {
  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);
  if (url.origin !== self.location.origin || url.pathname.startsWith("/api")) {
    return;
  }

  // Page navigations must never be answered with a synthetic Response.error() -
  // Chrome/Edge render that as a native "This page couldn't load" interstitial
  // instead of the app. Let the browser handle navigations directly; only
  // static assets (JS/CSS/images) go through the offline-cache fallback below.
  if (request.mode === "navigate") {
    return;
  }

  event.respondWith(
    fetch(request)
      .then((response) => {
        const responseClone = response.clone();
        return caches
          .open(CACHE_NAME)
          .then((cache) => cache.put(request, responseClone))
          .then(() => response);
      })
      .catch(() => caches.match(request).then((cached) => cached || Response.error())),
  );
});