YOUserbase/CreateGroupPage.xaml.cs

namespace YOUserbase;

public partial class CreateGroupPage : ContentPage {

    private Group group;

    public CreateGroupPage() {
        InitializeComponent();
    }

    public CreateGroupPage(Group group) {
        InitializeComponent();
        this.group = group;
        NameEntry.Text = group.Name;
        DetailsEntry.Text = group.Details;
        btnCreate.Text = "Save";
        contentPage.Title = "Edit user";
    }

    private void OnCreateClicked(object sender, EventArgs e) {
        var isValid = true;
        string text = NameEntry.Text;
        errName.Text = "";
        if(String.IsNullOrWhiteSpace(text)) {
            isValid = false;
            errName.Text = "First name cannot be empty";
        } else if(text.Length > 20) {
            isValid = false;
            errName.Text = "First name cannot be longer than 20 characters";
        }
        text = DetailsEntry.Text;
        errDetails.Text = "";
        if(String.IsNullOrWhiteSpace(text)) {
            isValid = false;
            errDetails.Text = "Last name cannot be empty";
        } else if(text.Length > 500) {
            isValid = false;
            errDetails.Text = "Last name cannot be longer than 20 characters";
        }
        errAll.Text = "";
        if(Data.Groups.Where(x => x.Name == NameEntry.Text).Any()) {
            isValid = false;
            errAll.Text = "Group with the same name already exists";
        }
        if(isValid) {
            if(group != null) { // Update
                var grp = Data.Groups.FirstOrDefault(gr => gr.Id == group.Id);
                grp.Name = NameEntry.Text;
                grp.Details = DetailsEntry.Text;
            } else { // Create
                Data.Groups.Add(new Group {
                    Name = NameEntry.Text,
                    Details = DetailsEntry.Text,
                });
            }
            Navigation.PopAsync();
        }
    }
}