service-worker.js

const CACHE_NAME = 'nomad-coffee-v1';
const STATIC_CACHE = 'static-v1';
const DYNAMIC_CACHE = 'dynamic-v1';
const RUNTIME_CACHE = 'runtime-v1';

const STATIC_ASSETS = [
    '/',
    '/index.html',
    '/styles/main.css',
    '/styles/hero.css',
    'https://unpkg.com/react@18/umd/react.production.min.js',
    'https://unpkg.com/react-dom@18/umd/react-dom.production.min.js',
    'https://unpkg.com/@babel/standalone/babel.min.js',
    'https://cdn.tailwindcss.com'
];

const DYNAMIC_ASSETS = [
    '/styles/header.css',
    '/styles/products.css',
    '/styles/footer.css',
    '/styles/animations.css',
    '/styles/cart.css',
    '/styles/about.css',
    '/styles/locations.css',
    '/styles/contact.css'
];

self.addEventListener('install', event => {
    event.waitUntil(
        Promise.all([
            caches.open(STATIC_CACHE).then(cache => cache.addAll(STATIC_ASSETS)),
            caches.open(DYNAMIC_CACHE).then(cache => cache.addAll(DYNAMIC_ASSETS))
        ])
    );
});

self.addEventListener('activate', event => {
    event.waitUntil(
        caches.keys().then(cacheNames => {
            return Promise.all(
                cacheNames
                    .filter(cacheName => 
                        cacheName.startsWith('nomad-') && 
                        ![STATIC_CACHE, DYNAMIC_CACHE, RUNTIME_CACHE].includes(cacheName)
                    )
                    .map(cacheName => caches.delete(cacheName))
            );
        })
    );
});

self.addEventListener('fetch', event => {
    // Skip cross-origin requests
    if (!event.request.url.startsWith(self.location.origin)) {
        return;
    }

    event.respondWith(
        caches.match(event.request)
            .then(cachedResponse => {
                if (cachedResponse) {
                    // Return cached response and update cache in background
                    if (navigator.onLine) {
                        fetch(event.request)
                            .then(response => {
                                if (response.ok) {
                                    caches.open(RUNTIME_CACHE)
                                        .then(cache => cache.put(event.request, response));
                                }
                            });
                    }
                    return cachedResponse;
                }

                return fetch(event.request)
                    .then(response => {
                        if (!response || response.status !== 200 || response.type !== 'basic') {
                            return response;
                        }

                        const responseToCache = response.clone();
                        caches.open(RUNTIME_CACHE)
                            .then(cache => {
                                cache.put(event.request, responseToCache);
                            });

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

// Cache cleanup
self.addEventListener('message', event => {
    if (event.data === 'clearOldCaches') {
        caches.keys().then(cacheNames => {
            return Promise.all(
                cacheNames.map(cacheName => {
                    if (cacheName !== CACHE_NAME) {
                        return caches.delete(cacheName);
                    }
                })
            );
        });
    }
});