const sw = self as unknown as ServiceWorkerGlobalScope;

interface ExtendableEvent extends Event {
    waitUntil(fn: Promise<unknown>): void;
}
interface PushEvent extends ExtendableEvent {
    data: PushMessageData | null;
}
interface PushMessageData {
    json(): unknown;
    text(): string;
}
interface NotificationEvent extends ExtendableEvent {
    notification: Notification;
}

// ──────────────────────────────────────────────────────────────────────────────
// Service Worker: Install & Activate
// ──────────────────────────────────────────────────────────────────────────────

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

sw.addEventListener('activate', (event: Event) => {
    (event as ExtendableEvent).waitUntil(sw.clients.claim());
});

// ──────────────────────────────────────────────────────────────────────────────
// Push Notification Handler
// ──────────────────────────────────────────────────────────────────────────────

sw.addEventListener('push', (event: Event) => {
    const pushEvent = event as PushEvent;

    if (!pushEvent.data) {
return;
}

    let data: { title?: string; body?: string; icon?: string; url?: string } =
        {};

    try {
        data = pushEvent.data.json() as typeof data;
    } catch {
        data = { title: 'DST Collection', body: pushEvent.data.text() };
    }

    const title = data.title ?? 'DST Collection';
    const options: NotificationOptions = {
        body: data.body ?? '',
        icon: data.icon ?? '/assets/pwa-192x192.png',
        badge: '/assets/pwa-64x64.png',
        data: { url: data.url ?? '/admin/master/categories' },
        tag: 'dst-notification',
        renotify: true,
    };

    pushEvent.waitUntil(sw.registration.showNotification(title, options));
});

// ──────────────────────────────────────────────────────────────────────────────
// Notification Click Handler
// ──────────────────────────────────────────────────────────────────────────────

sw.addEventListener('notificationclick', (event: Event) => {
    const notifEvent = event as NotificationEvent;
    notifEvent.notification.close();

    const targetUrl: string =
        (notifEvent.notification.data?.url as string) ?? '/admin/dashboard';

    notifEvent.waitUntil(
        sw.clients
            .matchAll({ type: 'window', includeUncontrolled: true })
            .then((clientList) => {
                for (const client of clientList) {
                    if ('focus' in client) {
                        return (client as WindowClient)
                            .navigate(targetUrl)
                            .then((c) => c?.focus());
                    }
                }

                return sw.clients.openWindow(targetUrl);
            }),
    );
});