sw.js

// Service Worker for Numo PWA
const CACHE_NAME = 'numo-v4';
const urlsToCache = [
    '/',
    '/index.html',
    '/manifest.json',
    '/css/styles.css',
    '/css/modal.css',
    '/css/mode-toggle.css',
    '/css/alphabet-learning.css',
    '/css/catch-game.css',
    '/js/app.js',
    '/js/settings.js',
    '/js/learning.js',
    '/js/alphabet-learning.js',
    '/js/practice.js',
    '/js/alphabet-practice.js',
    '/js/catch-game.js',
    '/icons/icon-192.png',
    '/icons/icon-512.png',
    '/assets/images/dino1.png',
    '/assets/images/dino2.png',
    '/assets/images/dino3.png',
    '/assets/images/dino4.png',
    '/assets/images/dino5.png',
    '/assets/images/dino6.png',
    '/assets/images/truck1.png',
    '/assets/images/truck2.png',
    '/assets/images/truck3.png',
    '/assets/images/truck4.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);
            })
    );
});

// Fetch event - serve from cache, fallback to network
self.addEventListener('fetch', (event) => {
    event.respondWith(
        caches.match(event.request)
            .then((response) => {
                // Cache hit - return response
                if (response) {
                    return response;
                }

                // For cross-origin requests (like Google Fonts)
                return fetch(event.request).then(
                    (response) => {
                        // Check if we received a valid response
                        if (!response || response.status !== 200 || response.type !== 'basic') {
                            return response;
                        }

                        // IMPORTANT: Clone the response. A response is a stream
                        // and because we want the browser to consume the response
                        // as well as the cache consuming the response, we need
                        // to clone it so we have two streams.
                        var responseToCache = response.clone();

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

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

// Activate event - clean up old caches
self.addEventListener('activate', (event) => {
    const cacheWhitelist = [CACHE_NAME];
    event.waitUntil(
        caches.keys().then((cacheNames) => {
            return Promise.all(
                cacheNames.map((cacheName) => {
                    if (cacheWhitelist.indexOf(cacheName) === -1) {
                        return caches.delete(cacheName);
                    }
                })
            );
        })
    );
});