// Service Worker for WarehouseTrack Pro PWA
const CACHE_NAME = 'warehousetrack-v1';
const urlsToCache = [
  '/',
  '/manifest.json',
  '/src/index.css',
  '/src/main.tsx',
  'https://fonts.googleapis.com/css2?family=Roboto:ital,wght@0,300;0,400;0,500;0,700;1,300;1,400;1,500;1,700&display=swap'
];

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

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

// Fetch event - Network First Strategy for API calls, Cache First for static assets
self.addEventListener('fetch', (event) => {
  const { request } = event;
  
  // Handle API requests with network-first strategy
  if (request.url.includes('/api/')) {
    event.respondWith(
      fetch(request)
        .then((response) => {
          // Don't cache POST/PUT/DELETE requests
          if (request.method === 'GET' && response.status === 200) {
            const responseClone = response.clone();
            caches.open(CACHE_NAME)
              .then((cache) => cache.put(request, responseClone));
          }
          return response;
        })
        .catch(() => {
          // Fall back to cache if network fails
          return caches.match(request);
        })
    );
    return;
  }
  
  // Handle static assets with cache-first strategy
  event.respondWith(
    caches.match(request)
      .then((response) => {
        // Return cached version or fetch from network
        return response || fetch(request)
          .then((response) => {
            // Don't cache non-successful responses
            if (!response || response.status !== 200 || response.type !== 'basic') {
              return response;
            }
            
            const responseToCache = response.clone();
            caches.open(CACHE_NAME)
              .then((cache) => cache.put(request, responseToCache));
            
            return response;
          });
      })
  );
});

// Handle background sync for offline actions
self.addEventListener('sync', (event) => {
  if (event.tag === 'stock-update') {
    event.waitUntil(
      // Handle offline stock updates when back online
      handleOfflineStockUpdates()
    );
  }
});

// Placeholder function for handling offline updates
function handleOfflineStockUpdates() {
  return Promise.resolve();
}