const CACHE_NAME = 'linkding-v2.0.1';
const urlsToCache = [
  '/',
  '/index.html',
  '/styles.css',
  '/app.js',
  '/manifest.json',
  '/icon-192.png',
  '/icon-512.png'
];

// Install event - cache resources
self.addEventListener('install', (event) => {
  event.waitUntil(
    caches.open(CACHE_NAME)
      .then((cache) => {
        console.log('Opened cache');
        return cache.addAll(urlsToCache);
      })
      .catch((error) => {
        console.error('Cache install failed:', error);
      })
  );
  self.skipWaiting();
});

// Activate event - clean up old caches
self.addEventListener('activate', (event) => {
  event.waitUntil(
    caches.keys().then((cacheNames) => {
      return Promise.all(
        cacheNames.map((cacheName) => {
          if (cacheName !== CACHE_NAME) {
            console.log('Deleting old cache:', cacheName);
            return caches.delete(cacheName);
          }
        })
      );
    }).then(() => {
      // Claim all clients immediately to ensure new service worker takes control
      return self.clients.claim();
    })
  );
});

// Fetch event - network first for HTML/CSS/JS, cache first for images
self.addEventListener('fetch', (event) => {
  // API requests - always fetch from network, don't cache
  if (event.request.url.includes('/api/')) {
    event.respondWith(fetch(event.request));
    return;
  }

  const url = new URL(event.request.url);
  const isHTML = event.request.destination === 'document' || url.pathname === '/' || url.pathname.endsWith('.html');
  const isCSS = url.pathname.endsWith('.css');
  const isJS = url.pathname.endsWith('.js');
  const isImage = event.request.destination === 'image' || url.pathname.match(/\.(png|jpg|jpeg|gif|svg|webp|ico)$/i);

  // For HTML, CSS, and JS: Network first, then cache (for offline support)
  if (isHTML || isCSS || isJS) {
    event.respondWith(
      fetch(event.request)
        .then((response) => {
          // Don't cache non-successful responses
          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;
        })
        .catch(() => {
          // Network failed, try cache
          return caches.match(event.request).then((response) => {
            // If it's a document request and cache fails, return index.html
            if (!response && isHTML) {
              return caches.match('/index.html');
            }
            return response;
          });
        })
    );
    return;
  }

  // For images and other static assets: Cache first, then network
  if (isImage) {
    event.respondWith(
      caches.match(event.request)
        .then((response) => {
          // Return cached version or fetch from network
          return response || fetch(event.request).then((response) => {
            // Don't cache non-successful responses
            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;
          });
        })
        .catch(() => {
          // If both cache and network fail, return offline page if available
          if (event.request.destination === 'document') {
            return caches.match('/index.html');
          }
        })
    );
    return;
  }

  // For other requests: Network first
  event.respondWith(fetch(event.request));
});