const CACHE_NAME = 'mykindlebox-shell-v1'
const SHELL_URLS = ['/', '/favicon.svg', '/icon-192.png', '/manifest.json']

self.addEventListener('install', (event) => {
  event.waitUntil(caches.open(CACHE_NAME).then((cache) => cache.addAll(SHELL_URLS)))
})

self.addEventListener('activate', (event) => {
  event.waitUntil(
    caches
      .keys()
      .then((keys) => Promise.all(keys.filter((key) => key !== CACHE_NAME).map((key) => caches.delete(key))))
      .then(() => self.clients.claim()),
  )
})

// Network-first with a cache fallback for the app shell (HTML/JS/CSS/static
// assets), so a previously-visited bundle still loads offline. API requests
// are left alone — they should fail fast so the UI can show its own inline
// "offline" state instead of serving stale data silently.
self.addEventListener('fetch', (event) => {
  const { request } = event
  if (request.method !== 'GET') return

  const url = new URL(request.url)
  if (url.pathname.startsWith('/api/') || url.pathname.startsWith('/uploads/')) return

  event.respondWith(
    fetch(request)
      .then((response) => {
        if (response.ok) {
          const copy = response.clone()
          caches.open(CACHE_NAME).then((cache) => cache.put(request, copy))
        }
        return response
      })
      .catch(() => caches.match(request).then((cached) => cached ?? caches.match('/'))),
  )
})