dist/service-worker.js

const CACHE_NAME = 'pattanshetty-v2';
const urlsToCache = [
    '/',
    '/index.html',
];

// Install event - cache resources
self.addEventListener('install', (event) => {
    console.log('[ServiceWorker] Installing...');
    event.waitUntil(
        caches.open(CACHE_NAME)
            .then((cache) => {
                console.log('[ServiceWorker] Caching app shell');
                return cache.addAll(urlsToCache).catch((err) => {
                    console.error('[ServiceWorker] Cache addAll failed:', err);
                });
            })
            .catch((err) => {
                console.error('[ServiceWorker] Cache open failed:', err);
            })
    );
    self.skipWaiting();
});

// Activate event - clean up old caches
self.addEventListener('activate', (event) => {
    console.log('[ServiceWorker] Activating...');
    event.waitUntil(
        caches.keys().then((cacheNames) => {
            return Promise.all(
                cacheNames.map((cacheName) => {
                    if (cacheName !== CACHE_NAME) {
                        console.log('[ServiceWorker] Deleting old cache:', cacheName);
                        return caches.delete(cacheName);
                    }
                })
            );
        }).catch((err) => {
            console.error('[ServiceWorker] Activation failed:', err);
        })
    );
    self.clients.claim();
});

// Fetch event - Network first, fallback to cache
self.addEventListener('fetch', (event) => {
    // Skip non-GET requests
    if (event.request.method !== 'GET') {
        return;
    }

    event.respondWith(
        fetch(event.request)
            .then((response) => {
                // Check if valid response
                if (!response || response.status !== 200 || response.type === 'error') {
                    return response;
                }

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

                caches.open(CACHE_NAME)
                    .then((cache) => {
                        cache.put(event.request, responseToCache);
                    })
                    .catch((err) => {
                        console.error('[ServiceWorker] Cache put failed:', err);
                    });

                return response;
            })
            .catch((err) => {
                console.log('[ServiceWorker] Fetch failed, trying cache:', err);
                // Network failed, try cache
                return caches.match(event.request)
                    .then((cachedResponse) => {
                        if (cachedResponse) {
                            return cachedResponse;
                        }
                        // Return offline page or error
                        return new Response('Offline - No cached version available', {
                            status: 503,
                            statusText: 'Service Unavailable',
                            headers: new Headers({
                                'Content-Type': 'text/plain'
                            })
                        });
                    });
            })
    );
});