Fixing outlook attachments, re-using compose page and some additional fixes on the mime headers for outlook.

Wino.Mail.ViewModels/ComposePageViewModel.cs

@@ -21,11 +21,13 @@ using Wino.Core.Domain.Models.Navigation;
 using Wino.Core.Extensions;
 using Wino.Core.Services;
 using Wino.Mail.ViewModels.Data;
+using Wino.Mail.ViewModels.Messages;
 using Wino.Messaging.Client.Mails;
 
 namespace Wino.Mail.ViewModels;
 
-public partial class ComposePageViewModel : MailBaseViewModel
+public partial class ComposePageViewModel : MailBaseViewModel,
+    IRecipient<NewComposeDraftItemRequestedEvent>
 {
     public Func<Task<string>> GetHTMLBodyFunction;
 
@@ -432,6 +434,35 @@ public partial class ComposePageViewModel : MailBaseViewModel
         }
     }
 
+    public async void Receive(NewComposeDraftItemRequestedEvent message)
+    {
+        // Save current draft before switching.
+        await UpdateMimeChangesAsync();
+
+        // Reset state for the new draft.
+        isUpdatingMimeBlocked = false;
+        ComposingAccount = null;
+        IncludedAttachments.Clear();
+
+        // Set the new draft item and prepare it.
+        CurrentMailDraftItem = message.MailItemViewModel;
+        await TryPrepareComposeAsync(true);
+    }
+
+    protected override void RegisterRecipients()
+    {
+        base.RegisterRecipients();
+
+        Messenger.Register<NewComposeDraftItemRequestedEvent>(this);
+    }
+
+    protected override void UnregisterRecipients()
+    {
+        base.UnregisterRecipients();
+
+        Messenger.Unregister<NewComposeDraftItemRequestedEvent>(this);
+    }
+
     private async Task<bool> InitializeComposerAccountAsync()
     {
         if (CurrentMailDraftItem == null) return false;
@@ -550,6 +581,8 @@ public partial class ComposePageViewModel : MailBaseViewModel
     {
         if (CurrentMimeMessage == null) return;
 
+        IncludedAttachments.Clear();
+
         foreach (var attachment in CurrentMimeMessage.Attachments)
         {
             if (attachment.IsAttachment && attachment is MimePart attachmentPart)

Wino.Mail.ViewModels/MailListPageViewModel.cs

@@ -635,6 +635,56 @@ public partial class MailListPageViewModel : MailBaseViewModel,
 
             if (isFromDraftOrSentFolder)
             {
+                // Fix for draft duplication: When a draft is created for reply/forward, it's first added as local draft.
+                // Then the server sync fetches it back. We should skip adding remote drafts if a local draft already exists
+                // with the same ThreadId. The mapping system (DraftMapped) will handle updating the existing local draft.
+                if (addedMail.IsDraft && !addedMail.IsLocalDraft && !string.IsNullOrEmpty(addedMail.ThreadId))
+                {
+                    // Check if collection already has a local draft with the same ThreadId in the same folder
+                    bool hasLocalDraftInSameThread = false;
+                    
+                    foreach (var group in MailCollection.MailItems)
+                    {
+                        foreach (var item in group)
+                        {
+                            if (item is MailItemViewModel mailItem)
+                            {
+                                if (mailItem.IsDraft &&
+                                    mailItem.MailCopy.IsLocalDraft &&
+                                    mailItem.MailCopy.ThreadId == addedMail.ThreadId &&
+                                    mailItem.MailCopy.FolderId == addedMail.FolderId)
+                                {
+                                    hasLocalDraftInSameThread = true;
+                                    break;
+                                }
+                            }
+                            else if (item is ThreadMailItemViewModel threadItem)
+                            {
+                                foreach (var threadEmail in threadItem.ThreadEmails)
+                                {
+                                    if (threadEmail.IsDraft &&
+                                        threadEmail.MailCopy.IsLocalDraft &&
+                                        threadEmail.MailCopy.ThreadId == addedMail.ThreadId &&
+                                        threadEmail.MailCopy.FolderId == addedMail.FolderId)
+                                    {
+                                        hasLocalDraftInSameThread = true;
+                                        break;
+                                    }
+                                }
+                                if (hasLocalDraftInSameThread) break;
+                            }
+                        }
+                        if (hasLocalDraftInSameThread) break;
+                    }
+
+                    if (hasLocalDraftInSameThread)
+                    {
+                        // Local draft exists in the same thread - skip adding remote duplicate
+                        // The mapping system will update the local draft with remote IDs when DraftMapped message is received
+                        return;
+                    }
+                }
+
                 // Only add if the ThreadId exists in the collection (can be threaded with existing items)
                 if (!ThreadIdExistsInCollection(addedMail)) return;
             }
@@ -757,6 +807,17 @@ public partial class MailListPageViewModel : MailBaseViewModel,
         }
     }
 
+    protected override void OnDraftMapped(string localDraftCopyId, string remoteDraftCopyId)
+    {
+        base.OnDraftMapped(localDraftCopyId, remoteDraftCopyId);
+
+        // When a draft is mapped from local to remote, the database has been updated
+        // but the UI collection still references the MailCopy object with old IDs.
+        // The MailCollection.AddAsync method checks UniqueId (which doesn't change during mapping)
+        // so if mapping worked correctly, no duplicate should appear.
+        // This method is here for future enhancements if additional UI updates are needed.
+    }
+
     private async Task<List<MailItemViewModel>> PrepareMailViewModelsAsync(IEnumerable<MailCopy> mailItems, CancellationToken cancellationToken = default)
     {
         // Run ViewModel creation on background thread to avoid blocking UI

Wino.Mail.ViewModels/Messages/NewComposeDraftItemRequestedEvent.cs

@@ -0,0 +1,10 @@
+using Wino.Mail.ViewModels.Data;
+
+namespace Wino.Mail.ViewModels.Messages;
+
+/// <summary>
+/// When the compose page is already active, but a different draft item is selected.
+/// To not trigger navigation again and re-use existing WebView2 editor.
+/// </summary>
+/// <param name="MailItemViewModel">The new draft mail item to compose.</param>
+public record NewComposeDraftItemRequestedEvent(MailItemViewModel MailItemViewModel);