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

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

self.addEventListener('push', (event) => {
  if (!event.data) return;
  const payload = event.data.json();
  event.waitUntil(
    self.registration.showNotification(payload.title, {
      body: payload.body,
      icon: '/icons/icon-192.png',
      badge: '/icons/icon-192.png',
      tag: 'kc-task-done',
      data: { url: payload.url || '/dashboard.html' },
    })
  );
});

self.addEventListener('notificationclick', (event) => {
  event.notification.close();
  const targetUrl = event.notification.data && event.notification.data.url;
  if (!targetUrl) return;

  event.waitUntil(
    self.clients.matchAll({ type: 'window', includeUncontrolled: true }).then((clients) => {
      const existing = clients.find((c) => {
        try {
          return new URL(c.url).pathname === new URL(targetUrl, self.location.origin).pathname;
        } catch {
          return false;
        }
      });
      if (existing) return existing.focus();
      return self.clients.openWindow(targetUrl);
    })
  );
});