import { precacheAndRoute } from 'workbox-precaching'
import { offlineFallback } from 'workbox-recipes'
import { setDefaultHandler } from 'workbox-routing'
import { NetworkOnly } from 'workbox-strategies'
import manifest from './precache-manifest.json'

// ignore precache manifest generated by InjectManifest
// self.__WB_MANIFEST

precacheAndRoute(manifest)

self.addEventListener('install', () => {
  self.skipWaiting()
})

// Using network-only as the default strategy ensures that we fallback
// to the browser as if the service worker wouldn't exist.
// The browser may use own caching (HTTP cache).
// Also, the offline fallback only works if request matched a route
setDefaultHandler(new NetworkOnly())

// This won't work in dev because pages are never cached.
// See https://github.com/vercel/next.js/blob/337fb6a9aadb61c916f0121c899e463819cd3f33/server/render.js#L181-L185
offlineFallback({ pageFallback: '/offline' })

self.addEventListener('push', async function (event) {
  const payload = event.data?.json()
  if (!payload) return
  const { tag } = payload.options
  event.waitUntil((async () => {
    if (!['REPLY', 'MENTION'].includes(tag)) {
      return self.registration.showNotification(payload.title, payload.options)
    }

    const notifications = await self.registration.getNotifications({ tag })
    // since we used a tag filter, there should only be zero or one notification
    if (notifications.length > 1) {
      console.error(`more than one notification with tag ${tag} found`)
      return null
    }
    if (notifications.length === 0) {
      return self.registration.showNotification(payload.title, payload.options)
    }
    const currentNotification = notifications[0]
    const amount = currentNotification.data?.amount ? currentNotification.data.amount + 1 : 2
    let title = ''
    if (tag === 'REPLY') {
      title = `You have ${amount} new replies`
    } else if (tag === 'MENTION') {
      title = `You were mentioned ${amount} times`
    }
    currentNotification.close()
    const { icon } = currentNotification
    return self.registration.showNotification(title, { icon, tag, data: { url: '/notifications', amount } })
  })())
})

self.addEventListener('notificationclick', (event) => {
  const url = event.notification.data?.url
  if (url) {
    event.waitUntil(self.clients.openWindow(url))
  }
  event.notification.close()
})

self.addEventListener('pushsubscriptionchange', (event) => {
  // https://developer.mozilla.org/en-US/docs/Web/API/ServiceWorkerGlobalScope/pushsubscriptionchange_event
  const query = `
  mutation savePushSubscription($endpoint: String!, $p256dh: String!, $auth: String!, $oldEndpoint: String!) {
    savePushSubscription(endpoint: $endpoint, p256dh: $p256dh, auth: $auth, oldEndpoint: $oldEndpoint) {
      id
    }
  }`
  const subscription = self.registration.pushManager
    .subscribe(event.oldSubscription.options)
    .then((subscription) => {
      // convert keys from ArrayBuffer to string
      subscription = JSON.parse(JSON.stringify(subscription))
      const variables = {
        endpoint: subscription.endpoint,
        p256dh: subscription.keys.p256dh,
        auth: subscription.keys.auth,
        oldEndpoint: event.oldSubscription.endpoint
      }
      const body = JSON.stringify({ query, variables })
      return fetch('/api/graphql', {
        method: 'POST',
        headers: {
          'Content-type': 'application/json'
        },
        body
      })
    })
  event.waitUntil(subscription)
},
false
)