import type { DowncastFeedUrl } from './shared';
/**
 * Podcast feed subscription payload definition.
 */
export type Subscribe = {
    /**
     * A complete podcast feed URL using one of Downcast's documented feed schemes:
     * `itpc://`, `podcast://`, `feed://`, or `downcast://`.
     *
     * @example 'itpc://example.com/podcast/rss'
     */
    url: DowncastFeedUrl;
};
/**
 * Open a Downcast-supported podcast feed URL to import a subscription.
 *
 * Downcast documents `itpc://`, `podcast://`, `feed://`, and `downcast://` as
 * feed URL schemes that launch Downcast and attempt to import the podcast at
 * that URL.
 *
 * @param payload Podcast feed subscription payload.
 * @returns Downcast-supported podcast feed URL.
 * @example
 * subscribe({
 *   url: 'itpc://example.com/podcast/rss',
 * })
 * // => 'itpc://example.com/podcast/rss'
 * @link https://support.downcast.fm/article/efmhyEOyOj-url-schemes-opening-feed-ur-ls-mac
 */
export declare function subscribe(payload: Subscribe): `itpc://${string}` | `podcast://${string}` | `feed://${string}` | `downcast://${string}`;