PeerConnectiveChat/PCC2.Gui/Gui/Pcc2MainForm.cs

using Microsoft.AspNetCore.Components.WebView.WindowsForms;
using Microsoft.AspNetCore.Components.WebView;
using PCC2.AppScaffold;
using PCC2.EventBus;
using PCC2.Logging;
using PCC2.Gui.Events;

namespace PCC2.Gui
{
    public partial class Pcc2MainForm : Form
    {
        private IAsyncEventBus _eventBus = null!;
        private bool _isShuttingDown;
        private bool _isShuttingDownCompleted;

        public Pcc2MainForm()
        {
            InitializeComponent();
            Shown += Pcc2MainForm_Shown;
            FormClosing += Pcc2MainForm_FormClosing;
        }

        private async void Pcc2MainForm_Shown(object? sender, EventArgs e)
        {
            ApplicationInitializationStatusLabel.Text = "Building host...";
            Application.DoEvents();
            HostHolder.BuildHost();

            _eventBus = HostHolder.EventBus;

            async Task UiShowEventHandler(UiShownEvent obj)
            {
                ApplicationInitializationPanel.Hide();
                _eventBus.UnSubscript<UiShownEvent>(UiShowEventHandler);
#if DEBUG
                MainBlazorWebView.WebView.CoreWebView2.OpenDevToolsWindow();
#endif
            }
            _eventBus.Subscript((Func<UiShownEvent, Task>)UiShowEventHandler);

            async Task LocalMethod(LoggingEvent le)
            {
                if (ApplicationInitializationPanel.Visible == false) return;
                if (ApplicationInitializationStatusLabel.InvokeRequired)
                {
                    Invoke(delegate
                    {
                        ApplicationInitializationStatusLabel.Text = $"{le.LogLevel} {le.Content}";
                        Application.DoEvents();
                    });
                }
                else
                {
                    ApplicationInitializationStatusLabel.Text = $"{le.LogLevel} {le.Content}";
                }
            }

            HostHolder.EventBus.Subscript<LoggingEvent>(LocalMethod);

            ApplicationInitializationStatusLabel.Text = "Starting host...";
            Application.DoEvents();
            await HostHolder.StartAsync();

            async void OnUrlLoading(object? o, UrlLoadingEventArgs args)
            {
                MainBlazorWebView.UrlLoading -= OnUrlLoading;

                ApplicationInitializationStatusLabel.Text = "Loading UI...";
                Application.DoEvents();
            }

            MainBlazorWebView.UrlLoading += OnUrlLoading;

            MainBlazorWebView.HostPage = "wwwroot\\index.html";
            MainBlazorWebView.Services = HostHolder.ServiceProvider;
            MainBlazorWebView.RootComponents.Add<Blazor.MainUI>("#app");
        }

        private async void Pcc2MainForm_FormClosing(object? sender, FormClosingEventArgs e)
        {
            if (_isShuttingDownCompleted == false) e.Cancel = true;

            if (_isShuttingDown) return;
            _isShuttingDown = true;

            try
            {
                ApplicationInitializationPanel.Show();
                ApplicationInitializationTitleLabel.Text = "Application shutting down...";
                Application.DoEvents();

                await HostHolder.StopAsync();

                ApplicationInitializationStatusLabel.Text = "Window will close after 3 second...";
                Application.DoEvents();
                await Task.Delay(3000);
            }
            finally
            {
                _isShuttingDownCompleted = true;
                Close();
            }
        }
    }
}