public void Handle(AddWebClientCommand command)
        {
            if (UnitOfWork.AnyActual <WebClient>(x => x.User.Login == command.Login))
            {
                throw new InvalidOperationException("Table with the same name exists.");
            }

            var login      = command.Login;
            var secondHash = _passwordManager.CreateSecondHashFromFirst(command.FirstHash);

            var addedUser = UnitOfWork.Add(new User()
            {
                SecondHash = secondHash, Login = login
            });

            UnitOfWork.Add(new WebClient {
                FirstName = command.FirstHash, LastName = command.LastName, Phone = command.Phone, Mail = command.Mail, User = addedUser
            });
        }