src/web/static/sw.js

const CACHE_NAME = 'ri-v4';
const STATIC_ASSETS = [
  '/static/style.css',
  '/static/htmx.min.js',
  '/static/favicon.svg',
  '/static/manifest.json',
];

// Install: pre-cache static assets
self.addEventListener('install', (event) => {
  event.waitUntil(
    caches.open(CACHE_NAME).then((cache) => cache.addAll(STATIC_ASSETS))
  );
  self.skipWaiting();
});

// Activate: clean up old caches
self.addEventListener('activate', (event) => {
  event.waitUntil(
    caches.keys().then((keys) =>
      Promise.all(keys.filter((k) => k !== CACHE_NAME).map((k) => caches.delete(k)))
    )
  );
  self.clients.claim();
});

// Fetch: network-first for pages, cache-first for static assets
self.addEventListener('fetch', (event) => {
  const url = new URL(event.request.url);

  // Static assets: cache-first
  if (url.pathname.startsWith('/static/')) {
    event.respondWith(
      caches.match(event.request).then((cached) => {
        if (cached) return cached;
        return fetch(event.request).then((response) => {
          const clone = response.clone();
          caches.open(CACHE_NAME).then((cache) => cache.put(event.request, clone));
          return response;
        });
      })
    );
    return;
  }

  // Google Fonts: cache-first
  if (url.hostname.includes('fonts.googleapis.com') || url.hostname.includes('fonts.gstatic.com')) {
    event.respondWith(
      caches.match(event.request).then((cached) => {
        if (cached) return cached;
        return fetch(event.request).then((response) => {
          const clone = response.clone();
          caches.open(CACHE_NAME).then((cache) => cache.put(event.request, clone));
          return response;
        });
      })
    );
    return;
  }

  // HTML pages: network-first with cache fallback
  if (event.request.mode === 'navigate' || event.request.headers.get('accept')?.includes('text/html')) {
    event.respondWith(
      fetch(event.request)
        .then((response) => {
          const clone = response.clone();
          caches.open(CACHE_NAME).then((cache) => cache.put(event.request, clone));
          return response;
        })
        .catch(() => caches.match(event.request).then((cached) => cached || caches.match('/')))
    );
    return;
  }

  // Everything else: network with cache fallback
  event.respondWith(
    fetch(event.request).catch(() => caches.match(event.request))
  );
});