export function pushSessionToSW(baseUrl?: string, accessToken?: string, userId?: string) {
  if (!('serviceWorker' in navigator)) return;
  if (!navigator.serviceWorker.controller) return;

  navigator.serviceWorker.controller.postMessage({
    type: 'setSession',
    accessToken,
    baseUrl,
    userId,
  });
}

/**
 * Resolves once media requests can carry the session: immediately-ish when a
 * service worker already controls the page, otherwise when one takes control
 * (first visit / just updated) or after `timeoutMs`. Used to retry a media
 * load that raced the worker's activation and went out without a token.
 */
export function whenMediaAuthReady(timeoutMs = 3000): Promise<void> {
  return new Promise((resolve) => {
    const sw = 'serviceWorker' in navigator ? navigator.serviceWorker : undefined;
    if (!sw || sw.controller) {
      window.setTimeout(resolve, 500);
      return;
    }
    const done = () => {
      sw.removeEventListener('controllerchange', done);
      resolve();
    };
    sw.addEventListener('controllerchange', done);
    window.setTimeout(done, timeoutMs);
  });
}