GazpromApp/ViewModels/NewPointDialogViewModel.cs

using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Threading.Tasks;
using System.Web;
using Avalonia.Controls;
using Avalonia.Media.Imaging;
using Avalonia.Platform.Storage;
using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
using CommunityToolkit.Mvvm.Messaging;
using GazpromApp.Messages;
using Image = GazpromApp.Models.Image;
using Point = GazpromApp.Models.Point;

namespace GazpromApp.ViewModels;

public partial class NewPointDialogViewModel : ViewModelBase
{
    [ObservableProperty] 
    [NotifyCanExecuteChangedFor(nameof(EnterPointCommand))]
    private string? _name;
    
    [ObservableProperty]
    [NotifyCanExecuteChangedFor(nameof(EnterPointCommand))]
    private string? _description;
    
    public ObservableCollection<ImageViewModel> Images { get; } = [];

    [RelayCommand]
    private async Task AddImage(Window w)
    {
        IReadOnlyList<IStorageFile> files = await w.StorageProvider.OpenFilePickerAsync(new FilePickerOpenOptions()
        {
            AllowMultiple = true,
            Title = "Выберите одну или несколько картинок",
            FileTypeFilter = [FilePickerFileTypes.ImageAll],
        });
        foreach (var file in files)
            Images.Add(new ImageViewModel(new Image()) { FileName = new Bitmap(HttpUtility.UrlDecode(file.Path.AbsolutePath)) });
        
        IsImagesEmpty = Images.Count == 0;
    }
    
    [RelayCommand]
    private void DeleteImage(ImageViewModel image)
    {
        Images.Remove(image);
        IsImagesEmpty = Images.Count == 0;
    }
    
    private bool CanEnterPoint() => !string.IsNullOrEmpty(Name);
    
    [RelayCommand (CanExecute = nameof(CanEnterPoint))]
    private void EnterPoint()
    {
        Point point = new Point()
        {
            Name = Name,
            Description = Description,
            Images = Images.Select(e => e.GetImage()).ToList()
        };
        WeakReferenceMessenger.Default.Send(new NewPointDone(new PointViewModel(point)));
    }

    [RelayCommand]
    private static void CancelEnterPoint(Window w)
    {
        w.Close();
    }
    
    // Visual properties
    
    [ObservableProperty]
    private bool _isImagesEmpty = true;
}