Streamline auto-update process and refactor

DiscordChatExporter.Gui/Services/UpdateService.cs

@@ -9,8 +9,6 @@ namespace DiscordChatExporter.Gui.Services
 {
     public class UpdateService : IDisposable
     {
-        private readonly SettingsService _settingsService;
-
         private readonly IUpdateManager _updateManager = new UpdateManager(
             new GithubPackageResolver("Tyrrrz", "DiscordChatExporter", "DiscordChatExporter.zip"),
             new ZipPackageExtractor());
@@ -18,36 +16,25 @@ namespace DiscordChatExporter.Gui.Services
         private Version _updateVersion;
         private bool _updaterLaunched;
 
-        public UpdateService(SettingsService settingsService)
+        public async Task<Version> CheckForUpdatesAsync()
         {
-            _settingsService = settingsService;
+            var check = await _updateManager.CheckForUpdatesAsync();
+            return check.CanUpdate ? check.LastVersion : null;
         }
 
-        public async Task<Version> CheckPrepareUpdateAsync()
+        public async Task PrepareUpdateAsync(Version version)
         {
             try
             {
-                // If auto-update is disabled - don't check for updates
-                if (!_settingsService.IsAutoUpdateEnabled)
-                    return null;
-
-                // Check for updates
-                var check = await _updateManager.CheckForUpdatesAsync();
-                if (!check.CanUpdate)
-                    return null;
-
-                // Prepare the update
-                await _updateManager.PrepareUpdateAsync(check.LastVersion);
-
-                return _updateVersion = check.LastVersion;
+                await _updateManager.PrepareUpdateAsync(_updateVersion = version);
             }
             catch (UpdaterAlreadyLaunchedException)
             {
-                return null;
+                // Ignore race conditions
             }
             catch (LockFileNotAcquiredException)
             {
-                return null;
+                // Ignore race conditions
             }
         }
 
@@ -55,23 +42,20 @@ namespace DiscordChatExporter.Gui.Services
         {
             try
             {
-                // Check if an update is pending
-                if (_updateVersion == null)
+                if (_updateVersion == null || _updaterLaunched)
                     return;
 
-                // Check if the updater has already been launched
-                if (_updaterLaunched)
-                    return;
-
-                // Launch the updater
                 _updateManager.LaunchUpdater(_updateVersion, needRestart);
+
                 _updaterLaunched = true;
             }
             catch (UpdaterAlreadyLaunchedException)
             {
+                // Ignore race conditions
             }
             catch (LockFileNotAcquiredException)
             {
+                // Ignore race conditions
             }
         }
 

DiscordChatExporter.Gui/ViewModels/Framework/DialogManager.cs

@@ -22,46 +22,46 @@ namespace DiscordChatExporter.Gui.ViewModels.Framework
             var view = _viewManager.CreateAndBindViewForModelIfNecessary(dialogScreen);
 
             // Set up event routing that will close the view when called from viewmodel
-            DialogOpenedEventHandler onDialogOpened = (sender, e) =>
+            void OnDialogOpened(object sender, DialogOpenedEventArgs openArgs)
             {
                 // Delegate to close the dialog and unregister event handler
-                void OnScreenClosed(object o, CloseEventArgs args)
+                void OnScreenClosed(object o, CloseEventArgs closeArgs)
                 {
-                    e.Session.Close();
+                    openArgs.Session.Close();
                     dialogScreen.Closed -= OnScreenClosed;
                 }
 
                 dialogScreen.Closed += OnScreenClosed;
-            };
+            }
 
             // Show view
-            await DialogHost.Show(view, onDialogOpened);
+            await DialogHost.Show(view, OnDialogOpened);
 
             // Return the result
             return dialogScreen.DialogResult;
         }
 
-        public string PromptSaveFilePath(string filter = "All files|*.*", string initialFilePath = "")
+        public string PromptSaveFilePath(string filter = "All files|*.*", string defaultFilePath = "")
         {
             // Create dialog
             var dialog = new SaveFileDialog
             {
                 Filter = filter,
                 AddExtension = true,
-                FileName = initialFilePath,
-                DefaultExt = Path.GetExtension(initialFilePath) ?? ""
+                FileName = defaultFilePath,
+                DefaultExt = Path.GetExtension(defaultFilePath) ?? ""
             };
 
             // Show dialog and return result
             return dialog.ShowDialog() == true ? dialog.FileName : null;
         }
 
-        public string PromptDirectoryPath(string initialDirPath = "")
+        public string PromptDirectoryPath(string defaultDirPath = "")
         {
             // Create dialog
             var dialog = new VistaFolderBrowserDialog
             {
-                SelectedPath = initialDirPath
+                SelectedPath = defaultDirPath
             };
 
             // Show dialog and return result

DiscordChatExporter.Gui/ViewModels/Framework/Extensions.cs

@@ -36,9 +36,5 @@ namespace DiscordChatExporter.Gui.ViewModels.Framework
 
             return viewModel;
         }
-
-        public static ExportSetupViewModel CreateExportSetupViewModel(this IViewModelFactory factory,
-            GuildViewModel guild, ChannelViewModel channel)
-            => factory.CreateExportSetupViewModel(guild, new[] { channel });
     }
 }

DiscordChatExporter.Gui/ViewModels/RootViewModel.cs

@@ -4,6 +4,7 @@ using System.IO;
 using System.Linq;
 using System.Net;
 using System.Reflection;
+using System.Threading.Tasks;
 using DiscordChatExporter.Core.Models;
 using DiscordChatExporter.Core.Services;
 using DiscordChatExporter.Core.Services.Exceptions;
@@ -68,6 +69,39 @@ namespace DiscordChatExporter.Gui.ViewModels
                 (sender, args) => IsProgressIndeterminate = ProgressManager.IsActive && ProgressManager.Progress.IsEither(0, 1));
         }
 
+        private async Task HandleAutoUpdateAsync()
+        {
+            try
+            {
+                // Don't check for updates if auto-update is disabled
+                if (!_settingsService.IsAutoUpdateEnabled)
+                    return;
+
+                // Check for updates
+                var updateVersion = await _updateService.CheckForUpdatesAsync();
+                if (updateVersion == null)
+                    return;
+
+                // Notify user of an update and prepare it
+                Notifications.Enqueue($"Downloading update to DiscordChatExporter v{updateVersion}...");
+                await _updateService.PrepareUpdateAsync(updateVersion);
+
+                // Prompt user to install update (otherwise install it when application exits)
+                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");
+            }
+        }
+
         protected override async void OnViewLoaded()
         {
             base.OnViewLoaded();
@@ -83,24 +117,7 @@ namespace DiscordChatExporter.Gui.ViewModels
             }
 
             // Check and prepare update
-            try
-            {
-                var updateVersion = await _updateService.CheckPrepareUpdateAsync();
-                if (updateVersion != null)
-                {
-                    Notifications.Enqueue(
-                        $"Update to DiscordChatExporter v{updateVersion} will be installed when you exit",
-                        "INSTALL NOW", () =>
-                        {
-                            _updateService.FinalizeUpdate(true);
-                            RequestClose();
-                        });
-                }
-            }
-            catch
-            {
-                Notifications.Enqueue("Failed to perform application auto-update");
-            }
+            await HandleAutoUpdateAsync();
         }
 
         protected override void OnClose()