//-----------------------------------------------------------
// Вход:
// - если нет такого User, то "Invalid login or pswrd"
// Регистрация:
// - Чтобы поля не были пустыми
// - При регистрации чтобы не было дублирования Login
//-----------------------------------------------------------

//login
private void btnSubmit_Click(object sender, RoutedEventArgs e)
{
    var userName = txtBoxUserName.Text;
    var userPswrd = txtBoxPassword.Text;

    using (var db = new Model1())
    {
        var users = (from user in db.tblUsers
                        where user.NikName == userName && user.Password == userPswrd
                        select user).ToList();

        if (users.Count == 1)
        {
            MainWindow mainWindow = new MainWindow(users[0]);
            mainWindow.Show();
            this.Close();
        }
        else
        {
            MessageBox.Show("Incorrect enter");
        }
    }
}

private void btnRegistration_Click(object sender, RoutedEventArgs e)
{
    AddUserWndw addUserWndw = new AddUserWndw();
    addUserWndw.Show();
    this.Close();
}

//-------------------
//registration
private void btnSubmit_Click(object sender, RoutedEventArgs e)
{
    if ( !(ValidateRegistration()) )
    {
        return;
    }

    string login = txtBoxLogin.Text;
    string password = txtBoxPswrd.Text;
    string address = txtBoxAddress.Text;
    string tel = txtBoxTel.Text;
    int num = Convert.ToInt32(txtBoxIsAdmin.Text);
    bool _isAdmin = Convert.ToBoolean(num);

    using (var db = new Model1())
    {
        var users = (from user in db.tblUsers
                        where user.NikName == login
                        select user).ToList();

        if (users.Count == 1)
        {
            MessageBox.Show("User with current Login is exist");
            return;
        }

        tblUser newUser = new tblUser() { NikName = login, Password = password, Address = address, Tel = tel, IsAdmin = _isAdmin };
        db.tblUsers.Add(newUser);
        db.SaveChanges();
    }

    LoginScreenWndw loginScreenWndw = new LoginScreenWndw();
    loginScreenWndw.Show();
    this.Close();
}

private bool ValidateRegistration()
{
    if (txtBoxLogin.Text == "" || txtBoxPswrd.Text == "" || txtBoxAddress.Text == "" || txtBoxTel.Text == "" || txtBoxIsAdmin.Text == "")
    {
        MessageBox.Show("Please, fill the all poles");
        return false;
    }
    return true;
}

private void btnBack_Click(object sender, RoutedEventArgs e)
{
    LoginScreenWndw loginScreenWndw = new LoginScreenWndw();
    loginScreenWndw.Show();
    this.Close();
}