const CACHE_NAME = 'printer-central-cache-v1';
const urlsToCache = [
  'index.html',
  'manifest.json',
  'icon.png',
  'icons/icon-72.png',
  'icons/icon-96.png',
  'icons/icon-128.png',
  'icons/icon-144.png',
  'icons/icon-152.png',
  'icons/icon-192.png',
  'icons/icon-384.png',
  'icons/icon-512.png'
];

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

self.addEventListener('fetch', event => {
  event.respondWith(
    caches.match(event.request)
      .then(response => {
        // Cache hit - return response
        if (response) {
          return response;
        }
        return fetch(event.request);
      })
  );
});

self.addEventListener('activate', event => {
  const cacheWhitelist = [CACHE_NAME];
  event.waitUntil(
    caches.keys().then(keyList => {
      return Promise.all(keyList.map(key => {
        if (cacheWhitelist.indexOf(key) === -1) {
          return caches.delete(key);
        }
      }));
    })
  );
});