// OxiCloud Service Worker
const CACHE_NAME = 'oxicloud-cache-v4';
const ASSETS_TO_CACHE = [
  '/',
  '/index.html',
  '/js/i18n.js',
  '/js/languageSelector.js',
  '/locales/en.json',
  '/locales/es.json',
  '/locales/fa.json',
  '/locales/de.json',
  '/favicon.ico',
  'https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.0.0-beta3/css/all.min.css',
  'https://cdn.jsdelivr.net/npm/alpinejs@3.12.3/dist/cdn.min.js'
];

// Install event - cache assets
self.addEventListener('install', event => {
  event.waitUntil(
    caches.open(CACHE_NAME)
      .then(cache => {
        console.log('Cache opened');
        return cache.addAll(ASSETS_TO_CACHE);
      })
      .then(() => self.skipWaiting()) // Activate immediately
  );
});

// Activate event - clean old caches
self.addEventListener('activate', event => {
  event.waitUntil(
    caches.keys().then(cacheNames => {
      return Promise.all(
        cacheNames.filter(cacheName => {
          return cacheName !== CACHE_NAME;
        }).map(cacheName => {
          return caches.delete(cacheName);
        })
      );
    }).then(() => self.clients.claim()) // Take control of clients
  );
});

// Fetch event - serve from cache, update cache from network
self.addEventListener('fetch', event => {
  // Don't intercept API requests - let them go straight to the network
  if (event.request.url.includes('/api/')) {
    return;
  }
  
  event.respondWith(
    caches.match(event.request)
      .then(response => {
        // Cache hit - return the response from the cached version
        if (response) {
          // For non-core assets, still fetch from network for updates
          if (!ASSETS_TO_CACHE.includes(new URL(event.request.url).pathname)) {
            fetch(event.request).then(networkResponse => {
              if (networkResponse && networkResponse.status === 200) {
                const clonedResponse = networkResponse.clone();
                caches.open(CACHE_NAME).then(cache => {
                  cache.put(event.request, clonedResponse);
                });
              }
            }).catch(() => {
              // Ignore network fetch errors - we already have a cached version
            });
          }
          return response;
        }

        // Not in cache - get from network and add to cache
        return fetch(event.request).then(response => {
          if (!response || response.status !== 200 || response.type !== 'basic') {
            return response;
          }

          // Clone the response as it's a stream and can only be consumed once
          const responseToCache = response.clone();

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

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

// Background sync for failed requests
self.addEventListener('sync', event => {
  if (event.tag === 'oxicloud-sync') {
    event.waitUntil(
      // Implement background sync for pending file operations
      Promise.resolve() // Placeholder for actual implementation
    );
  }
});