DiscordChatExporter/DiscordChatExporter.Gui/ViewModels/RootViewModel.cs

using System;
using System.Threading.Tasks;
using DiscordChatExporter.Gui.Services;
using DiscordChatExporter.Gui.Utils;
using DiscordChatExporter.Gui.ViewModels.Components;
using DiscordChatExporter.Gui.ViewModels.Dialogs;
using DiscordChatExporter.Gui.ViewModels.Framework;
using DiscordChatExporter.Gui.ViewModels.Messages;
using MaterialDesignThemes.Wpf;
using Stylet;

namespace DiscordChatExporter.Gui.ViewModels;

public class RootViewModel : Screen, IHandle<NotificationMessage>, IDisposable
{
    private readonly IViewModelFactory _viewModelFactory;
    private readonly DialogManager _dialogManager;
    private readonly SettingsService _settingsService;
    private readonly UpdateService _updateService;

    public SnackbarMessageQueue Notifications { get; } = new(TimeSpan.FromSeconds(5));

    public DashboardViewModel Dashboard { get; }

    public RootViewModel(
        IViewModelFactory viewModelFactory,
        IEventAggregator eventAggregator,
        DialogManager dialogManager,
        SettingsService settingsService,
        UpdateService updateService
    )
    {
        _viewModelFactory = viewModelFactory;
        _dialogManager = dialogManager;
        _settingsService = settingsService;
        _updateService = updateService;

        eventAggregator.Subscribe(this);

        Dashboard = _viewModelFactory.CreateDashboardViewModel();

        DisplayName = $"{App.Name} v{App.VersionString}";
    }

    private async Task ShowUkraineSupportMessageAsync()
    {
        if (!_settingsService.IsUkraineSupportMessageEnabled)
            return;

        var dialog = _viewModelFactory.CreateMessageBoxViewModel(
            "Thank you for supporting Ukraine!",
            """
            As Russia wages a genocidal war against my country, I'm grateful to everyone who continues to stand with Ukraine in our fight for freedom.

            Click LEARN MORE to find ways that you can help.
            """,
            "LEARN MORE",
            "CLOSE"
        );

        // Disable this message in the future
        _settingsService.IsUkraineSupportMessageEnabled = false;
        _settingsService.Save();

        if (await _dialogManager.ShowDialogAsync(dialog) == true)
            ProcessEx.StartShellExecute("https://tyrrrz.me/ukraine?source=discordchatexporter");
    }

    private async ValueTask CheckForUpdatesAsync()
    {
        try
        {
            var updateVersion = await _updateService.CheckForUpdatesAsync();
            if (updateVersion is null)
                return;

            Notifications.Enqueue($"Downloading update to {App.Name} v{updateVersion}...");
            await _updateService.PrepareUpdateAsync(updateVersion);

            Notifications.Enqueue(
                "Update has been downloaded and will be installed when you exit",
                "INSTALL NOW",
                () =>
                {
                    _updateService.FinalizeUpdate(true);
                    RequestClose();
                }
            );
        }
        catch
        {
            // Failure to update shouldn't crash the application
            Notifications.Enqueue("Failed to perform application update");
        }
    }

    public async void OnViewFullyLoaded()
    {
        await ShowUkraineSupportMessageAsync();
        await CheckForUpdatesAsync();
    }

    protected override void OnViewLoaded()
    {
        base.OnViewLoaded();

        _settingsService.Load();

        // Sync the theme with settings
        if (_settingsService.IsDarkModeEnabled)
        {
            App.SetDarkTheme();
        }
        else
        {
            App.SetLightTheme();
        }

        // App has just been updated, display the changelog
        if (
            _settingsService.LastAppVersion is not null
            && _settingsService.LastAppVersion != App.Version
        )
        {
            Notifications.Enqueue(
                $"Successfully updated to {App.Name} v{App.VersionString}",
                "WHAT'S NEW",
                () => ProcessEx.StartShellExecute(App.LatestReleaseUrl)
            );

            _settingsService.LastAppVersion = App.Version;
            _settingsService.Save();
        }
    }

    protected override void OnClose()
    {
        base.OnClose();

        _settingsService.Save();
        _updateService.FinalizeUpdate(false);
    }

    public void Handle(NotificationMessage message) => Notifications.Enqueue(message.Text);

    public void Dispose() => Notifications.Dispose();
}