const CACHE_NAME = 'bt-preview-v1'
const SHELL = ['/', '/gate', '/settings', '/manifest.json', '/icon.svg']

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

self.addEventListener('activate', (event) => {
  event.waitUntil(self.clients.claim())
})

self.addEventListener('fetch', (event) => {
  const { request } = event
  const url = new URL(request.url)

  // API、图片预览、下载等动态请求走网络，不做缓存
  if (url.pathname.startsWith('/api/')) return

  event.respondWith(
    caches.match(request).then((cached) => {
      if (cached) return cached
      return fetch(request).then((res) => {
        if (request.method === 'GET' && res.status === 200 && res.type === 'basic') {
          const clone = res.clone()
          caches.open(CACHE_NAME).then((cache) => cache.put(request, clone)).catch(() => {})
        }
        return res
      })
    })
  )
})