GazpromApp/Views/EditPointDialog.axaml.cs

using System;
using Avalonia.Controls;
using CommunityToolkit.Mvvm.Messaging;
using GazpromApp.Messages;
using GazpromApp.ViewModels;

namespace GazpromApp.Views;

public partial class EditPointDialog : Window
{
    public EditPointDialog()
    {
        InitializeComponent();
        
        if (Design.IsDesignMode)
            return;
        
        // view image
        WeakReferenceMessenger.Default.Register<EditPointDialog, ViewImageMessage>(this, static (w, m) =>
        {
            var dialog = new ImageView
            {
                DataContext = m.Image
            };
            m.Reply(dialog.ShowDialog<ImageViewModel?>(w));
        });
        
        // error
        WeakReferenceMessenger.Default.Register<EditPointDialog, ErrorMessage>(this, static (w, m) =>
        {
            var dialog = new ErrorView
            {
                DataContext = m.Error
            };
            m.Reply(dialog.ShowDialog<ErrorViewModel?>(w));
        });
        
        // new equipment
        WeakReferenceMessenger.Default.Register<EditPointDialog, NewEquipmentMessage>(this, (w, m) =>
        {
            WeakReferenceMessenger.Default.Unregister<ErrorMessage>(this);
            var dialog = new NewEquipmentDialog
            {
                DataContext = new NewEquipmentDialogViewModel()
            };
            m.Reply(dialog.ShowDialog<EquipmentViewModel?>(w));
        });
        
        // edit equipment
        WeakReferenceMessenger.Default.Register<EditPointDialog, EditEquipmentMessage>(this, (w, m) =>
        {
            WeakReferenceMessenger.Default.Unregister<ViewImageMessage>(this);
            WeakReferenceMessenger.Default.Unregister<ErrorMessage>(this);
            var dialog = new EditEquipmentDialog
            {
                DataContext = new EditEquipmentDialogViewModel(m.Equipment)
            };
            m.Reply(dialog.ShowDialog<EquipmentViewModel?>(w));
        });
        
        // re registering error when new equipment done
        WeakReferenceMessenger.Default.Register<EditPointDialog, NewEquipmentDone>(this, (_, _) =>
        {
            if (!WeakReferenceMessenger.Default.IsRegistered<ErrorMessage>(this))
                WeakReferenceMessenger.Default.Register<EditPointDialog, ErrorMessage>(this, static (w, m) =>
                {
                    var dialog = new ErrorView
                    {
                        DataContext = m.Error
                    };
                    m.Reply(dialog.ShowDialog<ErrorViewModel?>(w));
                });
        });
        
        // re registering view image and error view
        WeakReferenceMessenger.Default.Register<EditPointDialog, EditEquipmentDone>(this, (_, _) =>
        {
            if (!WeakReferenceMessenger.Default.IsRegistered<ViewImageMessage>(this))
                WeakReferenceMessenger.Default.Register<EditPointDialog, ViewImageMessage>(this, static (w, m) =>
                {
                    var dialog = new ImageView
                    {
                        DataContext = m.Image
                    };
                    m.Reply(dialog.ShowDialog<ImageViewModel?>(w));
                });
            if (!WeakReferenceMessenger.Default.IsRegistered<ErrorMessage>(this))
                WeakReferenceMessenger.Default.Register<EditPointDialog, ErrorMessage>(this, static (w, m) =>
                {
                    var dialog = new ErrorView
                    {
                        DataContext = m.Error
                    };
                    m.Reply(dialog.ShowDialog<ErrorViewModel?>(w));
                });
        });
        
        // complete editing point
        WeakReferenceMessenger.Default.Register<EditPointDialog, EditPointDone>(this, static (w, m) =>
        {
            w.Close(m.Point);
        });
    }

    private void Window_OnClosing(object? sender, WindowClosingEventArgs e)
    {
        if (DataContext is EditPointDialogViewModel { IsClosed: false } vm)
            vm.CancelEditCommand.Execute(this);
    }

    private void Window_OnClosed(object? sender, EventArgs e)
    {
        WeakReferenceMessenger.Default.Unregister<ViewImageMessage>(this);
        WeakReferenceMessenger.Default.Unregister<ErrorMessage>(this);
        WeakReferenceMessenger.Default.Unregister<NewEquipmentMessage>(this);
        WeakReferenceMessenger.Default.Unregister<EditEquipmentMessage>(this);
        WeakReferenceMessenger.Default.Unregister<EditPointDone>(this);
    }
}