import { GoogleSignInCredentials, GoogleUserRetrievedData } from "../types";
export declare class GoogleAuthHandler {
    private readonly credentials;
    private services;
    constructor(credentials: GoogleSignInCredentials);
    /**
     * Initialize the Google Auth Handler.
     * This method fetches public keys, which is not necessary for regular ID token verification.
     * However, this is maintained for completeness or specific requirements.
     * @returns {Promise<void>}
     */
    initialize(): Promise<void>;
    /**
     * Decode and verify the provided ID token.
     * @param {string} idToken - The ID token to be decoded.
     * @returns {Promise<GoogleUserRetrievedData>} The decoded user data.
     */
    private decodeIdToken;
    /**
     * Validate user credentials using the provided ID token.
     * @param {object} params - Parameters containing the ID token.
     * @param {string} params.idToken - The ID token to be validated.
     * @returns {Promise<GoogleUserRetrievedData>} The validated user data.
     */
    validateUserCredentials({ idToken, }: {
        idToken: string;
    }): Promise<GoogleUserRetrievedData>;
    /**
     * Check if the token issuer is valid.
     * @param {string | undefined} issuer - The issuer to be validated.
     * @returns {boolean} True if the issuer is valid; otherwise, false.
     */
    private isIssuerValid;
}