const CACHE_NAME = 'zenith-v1';
const ASSETS_TO_CACHE = [
  '/',
  '/index.html',
  '/favicon.ico',
  '/manifest.json',
  '/vite.svg'
];

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

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

self.addEventListener('fetch', (event) => {
  // Only handle GET requests
  if (event.request.method !== 'GET') return;

  // SPA fallback for navigation requests
  if (event.request.mode === 'navigate') {
    event.respondWith(
      fetch(event.request).catch(() => {
        return caches.match('/index.html');
      })
    );
    return;
  }

  // Cache-first for static assets
  event.respondWith(
    caches.match(event.request).then((response) => {
      return response || fetch(event.request).then((fetchResponse) => {
        // Don't cache API calls or external resources unless necessary
        const url = new URL(event.request.url);
        if (url.origin === self.location.origin && url.pathname.startsWith('/assets/')) {
          return caches.open(CACHE_NAME).then((cache) => {
            cache.put(event.request, fetchResponse.clone());
            return fetchResponse;
          });
        }
        return fetchResponse;
      });
    })
  );
});