import { XSignInCredentials, XUserRetrievedData } from '../types';
/**
 * Class to handle authentication via Google's OAuth flow.
 * It handles exchanging the authorization code for tokens and
 * retrieving user information from the X API.
 */
export declare class XAuthHandler {
    private readonly credentials;
    private readonly _accessToken;
    /**
     * Constructor to initialize the class with client credentials.
     * The credentials are base64 encoded and stored as `_accessToken`.
     * @param credentials - The client credentials (client ID, client secret, etc.)
     */
    constructor(credentials: XSignInCredentials);
    /**
     * Exchanges the authorization code for an access token and refresh token.
     * Makes a POST request to the token exchange endpoint.
     * @param authorizationCode - The authorization code received from the user
     * @returns Promise resolving to the exchange data containing the access token, refresh token, and scope
     * @throws XAuthError if the token exchange fails
     */
    private exchangeAuthorizationCode;
    /**
     * Retrieves user information from the X API using the provided access token.
     * @param accessToken - The access token obtained from the token exchange
     * @returns Promise resolving to the user's information including ID, name, and username
     * @throws XAuthError if user information retrieval fails
     */
    private retrieveUserInfo;
    /**
     * Validates the user's credentials by exchanging the authorization code
     * and retrieving the user's information.
     * @param authorizationCode - The authorization code received from the user
     * @returns Promise resolving to the user's information if validation is successful
     * @throws XAuthError if validation fails or required scopes are not granted
     */
    validateUserCredentials({ authorizationCode }: {
        authorizationCode: string;
    }): Promise<XUserRetrievedData>;
}