/// <reference types="@sveltejs/kit" />
/// <reference no-default-lib="true"/>
/// <reference lib="esnext" />
/// <reference lib="webworker" />

import { build, files, version } from '$service-worker';
import { database } from './lib/Database/IDB/user';
import { notifications } from './lib/Data/AniList/notifications';

const sw = self as unknown as ServiceWorkerGlobalScope;

// Create a unique cache name for this deployment
const CACHE = `cache-${version}`;

const ASSETS = [
  ...build, // the app itself
  ...files // everything in `static`
];

sw.addEventListener('install', (event: ExtendableEvent) => {
  // Create a new cache and add all files to it
  async function addFilesToCache() {
    const cache = await caches.open(CACHE);
    await cache.addAll(ASSETS);
  }

  event.waitUntil(addFilesToCache());
});

sw.addEventListener('activate', (event) => {
  // Remove previous cached data from disk
  async function deleteOldCaches() {
    for (const key of await caches.keys()) {
      if (key !== CACHE) await caches.delete(key);
    }
  }

  event.waitUntil(deleteOldCaches());
});

sw.addEventListener('fetch', (event) => {
  // ignore POST requests etc
  if (event.request.method !== 'GET') return;

  const url = new URL(event.request.url).origin;

  if (url.startsWith('chrome-extension') || url.includes('extension') || url.indexOf('http') !== 0)
    return;

  async function respond() {
    const url = new URL(event.request.url);
    const cache = await caches.open(CACHE);

    // `build`/`files` can always be served from the cache
    if (ASSETS.includes(url.pathname)) {
      const response = await cache.match(url.pathname);

      if (response) {
        return response;
      }
    }

    // for everything else, try the network first, but
    // fall back to the cache if we're offline
    try {
      const response = await fetch(event.request);

      // if we're offline, fetch can return a value that is not a Response
      // instead of throwing - and we can't pass this non-Response to respondWith
      if (!(response instanceof Response)) {
        throw new Error('invalid response from fetch');
      }

      if (response.status === 200) {
        cache.put(event.request, response.clone());
      }

      return response;
    } catch (err) {
      const response = await cache.match(event.request);

      if (response) {
        return response;
      }

      // if there's no cache, then just error out
      // as there is nothing we can do to respond to this request
      throw err;
    }
  }

  event.respondWith(respond());
});

sw.addEventListener('push', async (event: PushEvent) => {
  event.waitUntil(
    (async () => {
      if (self.Notification && self.Notification.permission !== 'granted') {
        return;
      }

      try {
        const user = (await database.users.toArray()).at(0);

        if (!user) return;

        const recentNotifications = await notifications(user.user.accessToken);

        if (
          recentNotifications &&
          recentNotifications.length > 0 &&
          (recentNotifications[0].id > (user.lastNotificationID as number) ||
            new Date(recentNotifications[0].createdAt * 1000).getTime() + 30000 >
              new Date().getTime())
        ) {
          await database.users.update(user.id, { lastNotificationID: recentNotifications[0].id });
          await sw.registration.showNotification('due.moe', {
            body: `${recentNotifications[0].user.name}${recentNotifications[0].context}`,
            icon: recentNotifications[0].user.avatar.large || '/favicon-196x196.png',
            // Ref. https://stackoverflow.com/a/50805868/14452787
            tag: 'notification-1'
          });

          return;
        }
      } catch (error) {
        console.error(error);
      }

      if (
        navigator.userAgent.includes('Chrome') &&
        !(await sw.clients.matchAll({ type: 'window', includeUncontrolled: true })).some(
          (client) => client.visibilityState === 'visible'
        )
      ) {
        await sw.registration.showNotification('due.moe', {
          body: 'No new notifications',
          icon: '/favicon-196x196.png',
          tag: 'notification-1'
        });

        // Ref. https://github.com/firebase/quickstart-js/issues/126#issuecomment-504081087
        await new Promise((resolve) => {
          (resolve as unknown as () => void)();
          setTimeout(
            async () =>
              await sw.registration
                .getNotifications()
                .then((notifications) =>
                  notifications.forEach((notification) => notification.close())
                ),
            10
          );
        });
      }
    })()
  );
});

sw.addEventListener('notificationclick', (event: NotificationEvent) => {
  event.notification.close();
  event.waitUntil(sw.clients.openWindow('https://anilist.co/notifications'));
});