import { UsersService } from '../users/users.service';
export declare class TwoFactorAuthenticationService {
    private readonly usersService;
    constructor(usersService: UsersService);
    generateTwoFactorAuthenticationSecret(user: {
        id: string;
        email: string;
    }): Promise<{
        secret: string;
        otpauthUrl: string;
    }>;
    pipeQrCodeDataUrl(otpauthUrl: string): Promise<string>;
    isTwoFactorCodeValid(twoFactorCode: string, secret: string): Promise<boolean>;
}