// Service Worker for PWA support
const CACHE_NAME = 'clicker-game-cache-v1';
const urlsToCache = [
  '/',
  '/index.html',
  '/favicon.svg',
  '/manifest.json',
  '/icons/icon-192x192.png',
  '/icons/icon-512x512.png'
];

// Install the service worker and cache assets
self.addEventListener('install', (event) => {
  event.waitUntil(
    caches.open(CACHE_NAME)
      .then((cache) => {
        return cache.addAll(urlsToCache);
      })
  );
});

// Activate and clean up old caches
self.addEventListener('activate', (event) => {
  event.waitUntil(
    caches.keys().then((cacheNames) => {
      return Promise.all(
        cacheNames.map((cacheName) => {
          if (cacheName !== CACHE_NAME) {
            return caches.delete(cacheName);
          }
        })
      );
    })
  );
});

// Serve cached content when offline
self.addEventListener('fetch', (event) => {
  event.respondWith(
    caches.match(event.request)
      .then((response) => {
        // Cache hit - return the response from the cached version
        if (response) {
          return response;
        }
        
        // Not in cache - fetch from network
        return fetch(event.request).then(
          (response) => {
            // Check if we received a valid response
            if (!response || response.status !== 200 || response.type !== 'basic') {
              return response;
            }

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

            // Add to cache for future use
            caches.open(CACHE_NAME)
              .then((cache) => {
                cache.put(event.request, responseToCache);
              });

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