const CACHE_NAME = 'vbb-status-v20';
const urlsToCache = [
  '/',
  '/index.html',
  '/manifest.json',
  '/DotMatrix.ttf',
  '/images/favicon.png'
];

// Installation
self.addEventListener('install', event => {
  event.waitUntil(
    caches.open(CACHE_NAME)
      .then(cache => {
        console.log('Cache geöffnet');
        return cache.addAll(urlsToCache);
      })
  );
  self.skipWaiting();
});

// Aktivierung
self.addEventListener('activate', event => {
  event.waitUntil(
    caches.keys().then(cacheNames => {
      return Promise.all(
        cacheNames.map(cacheName => {
          if (cacheName !== CACHE_NAME) {
            console.log('Alter Cache wird gelöscht:', cacheName);
            return caches.delete(cacheName);
          }
        })
      );
    })
  );
  self.clients.claim();
});

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

        return fetch(event.request).then(
          response => {
            // Check if valid response
            if (!response || response.status !== 200 || response.type !== 'basic') {
              return response;
            }

            // Clone the response
            const responseToCache = response.clone();

            caches.open(CACHE_NAME)
              .then(cache => {
                cache.put(event.request, responseToCache);
              });

            return response;
          }
        );
      })
  );
});