bool wantToRegister = false;//allow user to create a client account and check if all data are valid
        private void Register_Click(object sender, RoutedEventArgs e)
        {
            LogIn.Visibility = Visibility.Collapsed;

            if (!wantToRegister)
            {
                ConfirmPassword.Visibility = Visibility.Visible;
                wantToRegister             = true;
                tBValidation.Text          = "Enter your data..";
                tBValidation.Foreground    = new SolidColorBrush(Colors.LightGreen);
            }
            else if (password.Text == tBConfirmPassword.Text)
            {
                if (!InterfaceManager.ValidPassword(password.Text))
                {
                    tBValidation.Foreground = new SolidColorBrush(Colors.Red);
                    tBValidation.Text       = "PassWord have to contain 8 characteres, upper and lower case";
                }
                else if (!uCollect.IsUser(userName.Text))
                {
                    User temp = new User(AutorisationLevel.Client, userName.Text, tBConfirmPassword.Text);
                    uCollect.AddUser(temp);
                    tBValidation.Text          = "Your account have been created.. you can login..";
                    tBValidation.Foreground    = new SolidColorBrush(Colors.LightGreen);
                    ConfirmPassword.Visibility = Visibility.Collapsed;
                    ClearUI();
                    LogIn.Visibility = Visibility.Visible;
                    wantToRegister   = false;
                }
                else
                {
                    tBValidation.Foreground = new SolidColorBrush(Colors.Red);
                    tBValidation.Text       = "An account already Exist with this username";
                }
            }
            else
            {
                tBValidation.Foreground = new SolidColorBrush(Colors.Red);
                tBValidation.Text       = "Your passwords are different";
            }
        }
        //Create a user
        private void createUser_Click(object sender, RoutedEventArgs e)
        {
            if (!InterfaceManager.ValidPassword(tBPasswordUser.Text))
            {
                PasswordValidation.Foreground = new SolidColorBrush(Colors.Red);
                PasswordValidation.Text       = "PassWord have to contain 8 characteres, upper and lower case";
                return;
            }
            string password = tBPasswordUser.Text;

            if (_uCollect.IsUser(tBNameUser.Text))
            {
                PasswordValidation.Foreground = new SolidColorBrush(Colors.Red);
                PasswordValidation.Text       = "Username already exist. Chose another one...";
                return;
            }
            string            name = tBNameUser.Text;
            AutorisationLevel autoLevel;

            if (rBEmployee.IsChecked == true)
            {
                autoLevel = AutorisationLevel.Employee;
            }
            else if (rBManager.IsChecked == true)
            {
                autoLevel = AutorisationLevel.Manager;
            }
            else
            {
                PasswordValidation.Foreground = new SolidColorBrush(Colors.Red);
                PasswordValidation.Text       = "Choose an autorisation Level";
                return;
            }

            User tmp = new User(autoLevel, name, password);

            _uCollect.AddUser(tmp);
            PasswordValidation.Foreground = new SolidColorBrush(Colors.Green);
            PasswordValidation.Text       = "User Created";
            ClearUIData();
        }