/**
 * Request app-specific token, passing in the token for the current app.
 *
 * This call returns a token after performing the same checks made by validateAppAccess.
 * It returns an app-specific token of the signed-in user only if the user has access
 * to the app and the encrypted platform cookie is valid.
 *
 * A scenario where an app would use this is if it is iframed into another platform app
 * and receives credentials via postMessage. Those credentials contain a token that is
 * specific to the host app, so the embedded app would use `exchangeToken` to get one
 * that is specific to itself.
 *
 * Note: This is only usable by Esri applications hosted on *arcgis.com, *esri.com or within
 * an ArcGIS Enterprise installation. Custom applications can not use this.
 *
 * @param token
 * @param clientId application
 * @param portal
 */
export declare function exchangeToken(token: string, clientId: string, portal?: string): Promise<string>;
/**
 * @internal
 * @private
 * Response from the `platformSelf(...)` function.
 */
export interface IPlatformSelfResponse {
    /**
     * Username of the user the encrypted cookie was issued for
     */
    username: string;
    /**
     * Token the consuming application can use, It is tied to the
     * clientId used in the `platformSelf` call
     */
    token: string;
    /**
     * Token expiration, in seconds-from-now
     */
    expires_in: number;
}
/**
 * @internal
 * @private
 * Request a token for a specific application using the esri_aopc encrypted cookie
 *
 * When a client app boots up, it will know its clientId and the redirectUri for use
 * in the normal /oauth/authorize pop-out oAuth flow.
 *
 * If the app sees an `esri_aopc` cookie (only set if the app is hosted on *.arcgis.com),
 * it can call the /oauth2/platformSelf end-point passing in the clientId and redirectUri
 * in headers, and it will receive back an app-specific token, assuming the user has
 * access to the app.
 *
 * Since there are scenarios where an app can boot using credentials/token from localstorage
 * but those credentials are not for the same user as the esri_aopc cookie, it is recommended that
 * an app check the returned username against any existing identity they may have loaded.
 *
 * Note: This is only usable by Esri applications hosted on *arcgis.com, *esri.com or within
 * an ArcGIS Enterprise installation. Custom applications can not use this.
 *
 * ```js
 * // convert the encrypted platform cookie into a ArcGISIdentityManager
 * import { platformSelf, ArcGISIdentityManager } from '@esri/arcgis-rest-request';
 *
 * const portal = 'https://www.arcgis.com/sharing/rest';
 * const clientId = 'YOURAPPCLIENTID';
 *
 * // exchange esri_aopc cookie
 * return platformSelf(clientId, 'https://your-app-redirect-uri', portal)
 * .then((response) => {
 *  const currentTimestamp = new Date().getTime();
 *  const tokenExpiresTimestamp = currentTimestamp + (response.expires_in * 1000);
 *  // Construct the session and return it
 *  return new ArcGISIdentityManager({
 *    portal,
 *    clientId,
 *    username: response.username,
 *    token: response.token,
 *    tokenExpires: new Date(tokenExpiresTimestamp),
 *    ssl: true
 *  });
 * })
 *
 * ```
 *
 *
 * @param clientId
 * @param redirectUri
 * @param portal
 */
export declare function platformSelf(clientId: string, redirectUri: string, portal?: string): Promise<IPlatformSelfResponse>;