Refactor busy state and progress reporting

DiscordChatExporter.Gui/ViewModels/RootViewModel.cs

@@ -121,6 +121,9 @@ namespace DiscordChatExporter.Gui.ViewModels
 
         public async void PopulateGuildsAndChannels()
         {
+            try
+            {
+                // Set busy state and indeterminate progress
                 IsEnabled = false;
                 Progress = -1;
 
@@ -135,11 +138,9 @@ namespace DiscordChatExporter.Gui.ViewModels
                 // Save token
                 _settingsService.LastToken = token;
 
-            // Clear existing
+                // Clear guild to channel map
                 _guildChannelsMap.Clear();
 
-            try
-            {
                 // Get DM channels
                 {
                     var channels = await _dataService.GetDirectMessageChannelsAsync(token);
@@ -158,6 +159,12 @@ namespace DiscordChatExporter.Gui.ViewModels
                             .ToArray();
                     }
                 }
+
+                // Update available guilds
+                AvailableGuilds = _guildChannelsMap.Keys.ToArray();
+
+                // Select the first guild
+                SelectedGuild = AvailableGuilds.FirstOrDefault();
             }
             catch (HttpErrorStatusCodeException ex) when (ex.StatusCode == HttpStatusCode.Unauthorized)
             {
@@ -167,18 +174,21 @@ namespace DiscordChatExporter.Gui.ViewModels
             {
                 Notifications.Enqueue("Forbidden – account may be locked by 2FA");
             }
-
-            AvailableGuilds = _guildChannelsMap.Keys.ToArray();
-            SelectedGuild = AvailableGuilds.FirstOrDefault();
-
+            finally
+            {
+                // Reset busy state and progress
                 Progress = 0;
                 IsEnabled = true;
             }            
+        }
 
         public bool CanExportChannel => IsEnabled;
 
         public async void ExportChannel(Channel channel)
         {
+            try
+            {
+                // Set busy state and indeterminate progress
                 IsEnabled = false;
                 Progress = -1;
 
@@ -190,12 +200,10 @@ namespace DiscordChatExporter.Gui.ViewModels
                 dialog.Guild = SelectedGuild;
                 dialog.Channel = channel;
 
-            // Show dialog
-            if (await _dialogManager.ShowDialogAsync(dialog) == true)
-            {
-                // Export
-                try
-                {
+                // Show dialog, if canceled - return
+                if (await _dialogManager.ShowDialogAsync(dialog) != true)
+                    return;
+
                 // Create progress handler
                 var progressHandler = new Progress<double>(p => Progress = p);
 
@@ -218,10 +226,12 @@ namespace DiscordChatExporter.Gui.ViewModels
             {
                 Notifications.Enqueue("This channel doesn't exist");
             }
-            }
-
+            finally
+            {
+                // Reset busy state and progress
                 Progress = 0;
                 IsEnabled = true;
             }
         }
     }
+}