static/sw.js

// IronGuard Service Worker - Offline First Strategy

const CACHE_NAME = 'ironguard-v1.0.0';
const urlsToCache = [
    '/',
    '/static/css/style.css',
    '/static/js/main.js',
    '/manifest.json'
];

// Install event - cache resources
self.addEventListener('install', (event) => {
    event.waitUntil(
        caches.open(CACHE_NAME)
            .then((cache) => {
                console.log('📦 Caching app shell');
                return cache.addAll(urlsToCache);
            })
    );
    self.skipWaiting();
});

// 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;
                }
                
                // Clone request
                const fetchRequest = event.request.clone();
                
                return fetch(fetchRequest).then((response) => {
                    // Check if valid response
                    if (!response || response.status !== 200 || response.type !== 'basic') {
                        return response;
                    }
                    
                    // Clone response
                    const responseToCache = response.clone();
                    
                    caches.open(CACHE_NAME)
                        .then((cache) => {
                            cache.put(event.request, responseToCache);
                        });
                    
                    return response;
                });
            })
    );
});

// Activate event - clean 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);
                    }
                })
            );
        })
    );
    self.clients.claim();
});