const CACHE = 'dodo-shell-v3'
const SHELL = ['/manifest.json', '/icon-192.png', '/icon-512.png', '/apple-touch-icon.png']
self.addEventListener('install', (event) => {
  self.skipWaiting()
  event.waitUntil(caches.open(CACHE).then((cache) => cache.addAll(SHELL)))
})
self.addEventListener('activate', (event) => {
  event.waitUntil(caches.keys().then((keys) => Promise.all(keys.filter((key) => key !== CACHE).map((key) => caches.delete(key)))).then(() => self.clients.claim()))
})
self.addEventListener('fetch', (event) => {
  const url = new URL(event.request.url)
  if (url.pathname.startsWith('/api/')) return
  if (event.request.method !== 'GET') return
  const isNavigation = event.request.mode === 'navigate'
  if (isNavigation) {
    event.respondWith(fetch(event.request).catch(() => caches.match('/offline.html')))
    return
  }
  event.respondWith(
    caches.match(event.request).then((cached) => cached || fetch(event.request).then((response) => {
      const copy = response.clone()
      caches.open(CACHE).then((cache) => cache.put(event.request, copy))
      return response
    })),
  )
})