import { AuthConfig, ServerType } from '@sasjs/utils/types';
import { RequestClient } from '../request/RequestClient';
/**
 * Callback invoked with the rotated token pair after a successful internal
 * refresh. Viya refresh tokens are single-use/rotating, so consumers that
 * persist tokens (e.g. the CLI writing `.env.{target}`) should pass a handler
 * wherever this is accepted to avoid the persisted pair going stale.
 */
export type OnTokensRefreshed = (tokens: {
    access_token: string;
    refresh_token: string;
}) => void | Promise<void>;
/**
 * Returns the auth configuration, refreshing the tokens if necessary.
 * This function can only be used by Node, if a server type is SASVIYA.
 * @param requestClient - the pre-configured HTTP request client
 * @param authConfig - an object containing a client ID, secret, access token and refresh token
 * @param serverType - server type for which refreshing the tokens, defaults to SASVIYA
 * @param onTokensRefreshed - optional callback invoked with the rotated token
 * pair after a successful internal refresh.
 */
export declare function getTokens(requestClient: RequestClient, authConfig: AuthConfig, serverType?: ServerType, onTokensRefreshed?: OnTokensRefreshed): Promise<AuthConfig>;