import type { Handle } from '@sveltejs/kit';

const ADMIN_HOSTNAME = 'admin.goodwalk.co.nz';
const ADMIN_PATH = '/owner/welcome';

function isAdminHost(hostname: string | undefined | null): boolean {
  if (!hostname) return false;
  return hostname.toLowerCase() === ADMIN_HOSTNAME;
}

export const handle: Handle = async ({ event, resolve }) => {
  const onAdminHost = isAdminHost(event.url.hostname);
  const path = event.url.pathname;

  // The admin host serves the dashboard at its root.
  if (onAdminHost && (path === '/' || path === '')) {
    return new Response(null, {
      status: 302,
      headers: { location: ADMIN_PATH },
    });
  }

  // Block the admin dashboard from the public marketing host so it only
  // lives on admin.goodwalk.co.nz in production. Localhost and the
  // onboarding subdomain are still allowed for development and migration.
  const hostname = event.url.hostname.toLowerCase();
  const isPublicMarketingHost = hostname === 'goodwalk.co.nz' || hostname === 'www.goodwalk.co.nz';
  if (isPublicMarketingHost && path.startsWith('/owner/')) {
    return new Response('Not Found', { status: 404 });
  }

  return resolve(event);
};