/// <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 {
	isNotificationQueued,
	notifications,
	updateLastNotificationID,
} from "./lib/Data/AniList/notifications";

const sw = self as unknown as ServiceWorkerGlobalScope;
const CACHE = `cache-${version}`;
const ASSETS = [...build, ...files];

sw.addEventListener("install", (event: ExtendableEvent) => {
	event.waitUntil(
		(async () => {
			const cache = await caches.open(CACHE);
			await cache.addAll(ASSETS);
		})(),
	);
});

sw.addEventListener("activate", (event) => {
	event.waitUntil(
		(async () => {
			for (const key of await caches.keys()) {
				if (key !== CACHE) await caches.delete(key);
			}
		})(),
	);
});

sw.addEventListener("fetch", (event) => {
	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);

		if (ASSETS.includes(url.pathname)) {
			const response = await cache.match(url.pathname);

			if (response) return response;
		}

		try {
			const response = await fetch(event.request);

			if (!(response instanceof Response))
				throw new Error("invalid response from fetch");

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

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

			if (response) return response;

			throw error;
		}
	}

	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 &&
					isNotificationQueued(recentNotifications, user.lastNotificationID)
				) {
					await updateLastNotificationID(user.id, recentNotifications);
					await sw.registration.showNotification("due.moe", {
						body: `${recentNotifications[0].user.name}${recentNotifications[0].context}`,
						icon:
							recentNotifications[0].user.avatar.large ||
							"/favicon-196x196.png",
						// 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",
				});

				// 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"));
});