Audit Kesiapan PWA Enterprise & Offline-First

{
  "name": "Portal Operasional Lapangan Korporat",
  "short_name": "PortalField",
  "start_url": "/",
  "display": "standalone",
  "background_color": "#020617",
  "theme_color": "#0B0F19",
  "icons": [
    {
      "src": "/icons/icon-192x192.png",
      "sizes": "192x192",
      "type": "image/png",
      "purpose": "any maskable"
    },
    {
      "src": "/icons/icon-512x512.png",
      "sizes": "512x512",
      "type": "image/png",
      "purpose": "any maskable"
    }
  ]
}

// service-worker.js (PuluhLabs Offline-First Engine)
const CACHE_NAME = 'app-cache-v1';
const OFFLINE_URL = '/offline';

const PRECACHE_ASSETS = [
  '/',
  '/offline',
  '/manifest.webmanifest',
  '/css/global.css',
  '/icons/icon-192x192.png',
];

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

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

self.addEventListener('fetch', (event) => {
  if (event.request.mode === 'navigate') {
    event.respondWith(
      fetch(event.request).catch(() => caches.match(OFFLINE_URL))
    );
    return;
  }

  // Strategy: STALE-WHILE-REVALIDATE
  event.respondWith(
    caches.match(event.request).then((cachedResponse) => {
      const fetchPromise = fetch(event.request).then((networkResponse) => {
        if (networkResponse && networkResponse.status === 200) {
          const responseToCache = networkResponse.clone();
          caches.open(CACHE_NAME).then((cache) => cache.put(event.request, responseToCache));
        }
        return networkResponse;
      });
      return cachedResponse || fetchPromise;
    })
  );
});