sw.js

// Service worker for offline fallback only (network-first)

const CACHE = "pwabuilder-offline-page-v2";

const offlineFallbackPage = "offline.html";

self.addEventListener("message", (event) => {
  if (event.data && event.data.type === "SKIP_WAITING") {
    self.skipWaiting();
  }
});

self.addEventListener('install', async (event) => {
  event.waitUntil(
    caches.open(CACHE)
      .then((cache) => cache.add(offlineFallbackPage))
  );
});

self.addEventListener('activate', (event) => {
  event.waitUntil(
    caches.keys().then((cacheNames) =>
      Promise.all(
        cacheNames
          .filter((name) => name !== CACHE)
          .map((name) => caches.delete(name))
      )
    )
  );
});

self.addEventListener('fetch', (event) => {
  if (event.request.mode === 'navigate') {
    event.respondWith((async () => {
      try {
        const networkResp = await fetch(event.request);
        return networkResp;
      } catch (error) {
        const cache = await caches.open(CACHE);
        const cachedResp = await cache.match(offlineFallbackPage);
        return cachedResp;
      }
    })());
  }
});