Fixing UI thread issues with bulk operations and request queue refactoring.

Wino.Core/Requests/Mail/ChangeFlagRequest.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using CommunityToolkit.Mvvm.Messaging;
 using Wino.Core.Domain.Entities.Mail;
 using Wino.Core.Domain.Enums;
@@ -25,25 +26,26 @@ public record ChangeFlagRequest(MailCopy Item, bool IsFlagged) : MailRequestBase
     /// If the mail is already in the desired flagged state, no change is needed.
     /// </summary>
     public bool IsNoOp { get; } = Item.IsFlagged == IsFlagged;
+    public bool OriginalIsFlagged => _originalIsFlagged;
+
+    public override object GroupingKey() => (Operation, Item.FolderId, IsFlagged);
 
     public override void ApplyUIChanges()
     {
-        // Skip UI update if the mail is already in the desired state
         if (IsNoOp) return;
 
-        Item.IsFlagged = IsFlagged;
-
-        WeakReferenceMessenger.Default.Send(new MailUpdatedMessage(Item, EntityUpdateSource.ClientUpdated, MailCopyChangeFlags.IsFlagged));
+        WeakReferenceMessenger.Default.Send(new MailStateUpdatedMessage(
+            new MailStateChange(Item.UniqueId, IsFlagged: IsFlagged),
+            EntityUpdateSource.ClientUpdated));
     }
 
     public override void RevertUIChanges()
     {
-        // Skip UI revert if this was a no-op request
         if (IsNoOp) return;
 
-        Item.IsFlagged = _originalIsFlagged;
-
-        WeakReferenceMessenger.Default.Send(new MailUpdatedMessage(Item, EntityUpdateSource.ClientReverted, MailCopyChangeFlags.IsFlagged));
+        WeakReferenceMessenger.Default.Send(new MailStateUpdatedMessage(
+            new MailStateChange(Item.UniqueId, IsFlagged: _originalIsFlagged),
+            EntityUpdateSource.ClientReverted));
     }
 }
 
@@ -52,4 +54,34 @@ public class BatchChangeFlagRequest : BatchCollection<ChangeFlagRequest>
     public BatchChangeFlagRequest(IEnumerable<ChangeFlagRequest> collection) : base(collection)
     {
     }
+
+    public override void ApplyUIChanges()
+    {
+        var updatedMails = this
+            .Where(x => !x.IsNoOp)
+            .Select(x => new MailStateChange(x.Item.UniqueId, IsFlagged: x.IsFlagged))
+            .ToList();
+
+        if (updatedMails.Count == 0)
+            return;
+
+        WeakReferenceMessenger.Default.Send(new BulkMailStateUpdatedMessage(
+            updatedMails,
+            EntityUpdateSource.ClientUpdated));
+    }
+
+    public override void RevertUIChanges()
+    {
+        var updatedMails = this
+            .Where(x => !x.IsNoOp)
+            .Select(x => new MailStateChange(x.Item.UniqueId, IsFlagged: x.OriginalIsFlagged))
+            .ToList();
+
+        if (updatedMails.Count == 0)
+            return;
+
+        WeakReferenceMessenger.Default.Send(new BulkMailStateUpdatedMessage(
+            updatedMails,
+            EntityUpdateSource.ClientReverted));
+    }
 }