const CACHE_NAME = 'bjorn-wiki-v2';
const STATIC_ASSETS = [
    './',
    './index.html',
    './config.js',
    './manifest.json',
    './assets/bjorn.png',
    'https://cdn.tailwindcss.com',
    'https://unpkg.com/lucide@latest',
    'https://cdn.jsdelivr.net/npm/marked/marked.min.js',
    'https://cdnjs.cloudflare.com/ajax/libs/dompurify/3.0.6/purify.min.js',
    'https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.9.0/styles/atom-one-dark.min.css',
    'https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.9.0/highlight.min.js',
    'https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@400;500;700&family=Inter:wght@400;500;600&display=swap'
];

// Install Event - Cache Static Assets
self.addEventListener('install', (event) => {
    event.waitUntil(
        caches.open(CACHE_NAME).then((cache) => {
            console.log('[SW] Caching static assets');
            return cache.addAll(STATIC_ASSETS);
        })
    );
    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('[SW] Deleting old cache:', cacheName);
                        return caches.delete(cacheName);
                    }
                })
            );
        })
    );
    self.clients.claim();
});

// Fetch Event - Stale-While-Revalidate Strategy
self.addEventListener('fetch', (event) => {
    // Skip non-GET requests
    if (event.request.method !== 'GET') return;

    // Strategy: Stale-While-Revalidate for most assets
    event.respondWith(
        caches.open(CACHE_NAME).then((cache) => {
            return cache.match(event.request).then((response) => {
                const fetchPromise = fetch(event.request).then((networkResponse) => {
                    // Cache the new response
                    if (networkResponse.ok) {
                        cache.put(event.request, networkResponse.clone());
                    }
                    return networkResponse;
                }).catch(() => {
                    // If network fails, we already returned the cached response if it exists
                });

                return response || fetchPromise;
            });
        })
    );
});