sw.js

const CACHE = 'regua-barsi-v8';
const ASSETS = [
  './',
  './index.html',
  './manifest.json',
  './icon-192.png',
  './icon-512.png'
];
self.addEventListener('install', e => {
  e.waitUntil(caches.open(CACHE).then(c => c.addAll(ASSETS)));
  self.skipWaiting();
});
self.addEventListener('activate', e => {
  e.waitUntil(caches.keys().then(keys => Promise.all(keys.filter(k => k !== CACHE).map(k => caches.delete(k)))));
  self.clients.claim();
});
self.addEventListener('fetch', e => {
  e.respondWith(
    caches.match(e.request).then(r => r || fetch(e.request).then(resp => {
      const copy = resp.clone();
      caches.open(CACHE).then(c => c.put(e.request, copy));
      return resp;
    }).catch(() => caches.match('./index.html')))
  );
});