AddLanguageModel.cs

using LegalLab.Models;
using LegalLab.Models.Standards;
using System.Threading.Tasks;
using System.Windows.Input;
 
namespace LegalLab.Dialogs.AddLanguage
{
    public class AddLanguageModel : Model
    {
        private readonly Property<string> selectedLanguage;
        private readonly AddLanguageDialog dialog;
        private readonly Command add;
        private readonly Command cancel;
 
        public AddLanguageModel(AddLanguageDialog Dialog)
        {
            this.selectedLanguage = new Property<string>(nameof(this.SelectedLanguage), string.Empty, this);
 
            this.dialog = Dialog;
            this.dialog.DataContext = this;
 
            this.add = new Command(this.CanExecuteAdd, this.ExecuteAdd);
            this.cancel = new Command(this.ExecuteCancel);
        }
 
        public string SelectedLanguage
        {
            get => this.selectedLanguage.Value;
            set
            {
                this.selectedLanguage.Value = value;
                this.add.RaiseCanExecuteChanged();
            }
        }
 
        public static Iso__639_1.Record[] Languages
        {
            get => Iso__639_1.Data;
        }
 
        public ICommand Add => this.add;
 
        public ICommand Cancel => this.cancel;
 
        private bool CanExecuteAdd()
        {
            return !string.IsNullOrEmpty(this.SelectedLanguage) && Iso__639_1.CodeToLanguage(this.SelectedLanguage, out _);
        }
 
        private Task ExecuteAdd()
        {
            this.dialog.DialogResult = true;
            return Task.CompletedTask;
        }
 
        private Task ExecuteCancel()
        {
            this.dialog.DialogResult = false;
            return Task.CompletedTask;
        }
    }
}