From 2d22db321c956714eef49895732c97907c276b59 Mon Sep 17 00:00:00 2001
From: bcbetterninja <327058824+bcbetterninja@users.noreply.github.com>
Date: Sun, 13 Sep 2026 20:45:16 +0000
Subject: [PATCH] Reject stale draft refreshes after quick deletion

---
 .../MainWindowViewModel.MessageActions.cs          |  2 ++
 src/BetterMail.App/MainWindowViewModel.cs          | 14 ++++++++++++--
 tests/BetterMail.Tests/MainWindowViewModelTests.cs |  4 ++++
 3 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/src/BetterMail.App/MainWindowViewModel.MessageActions.cs b/src/BetterMail.App/MainWindowViewModel.MessageActions.cs
index a24465c..0aacee7 100644
--- a/src/BetterMail.App/MainWindowViewModel.MessageActions.cs
+++ b/src/BetterMail.App/MainWindowViewModel.MessageActions.cs
@@ -17,6 +17,8 @@ internal async Task DeleteDraftQuickAsync(LocalDraft draft)
             var current = await _store.GetLocalDraftAsync(draft.Id);
             if (current is null || current.IsQueued) return;
             await _store.QueueDraftDeletionAsync(current);
+            // A refresh started before this commit must not resurrect its stale snapshot.
+            Interlocked.Increment(ref _draftRefreshVersion);
             var action = (await _store.GetMailActionsAsync()).FirstOrDefault(item => item.Kind == MailActionKind.DeleteDraft && item.ItemId == current.Id);
             if (action is not null) ShowQueuedAction(action);
             await feedback;
diff --git a/src/BetterMail.App/MainWindowViewModel.cs b/src/BetterMail.App/MainWindowViewModel.cs
index 47e1bf0..6ce2821 100644
--- a/src/BetterMail.App/MainWindowViewModel.cs
+++ b/src/BetterMail.App/MainWindowViewModel.cs
@@ -1875,19 +1875,29 @@ DraftSyncStatus.UnsupportedAttachment or
         }
     }
 
+    private int _draftRefreshVersion;
+
     private async Task RefreshDraftsAsync()
     {
         if (_store is null)
         {
             return;
         }
+        var version = Interlocked.Increment(ref _draftRefreshVersion);
         var drafts = await _store.GetLocalDraftSummariesAsync();
-        Replace(Drafts, drafts.Where(static draft => !draft.IsQueued));
-        Replace(Outbox, drafts.Where(static draft => draft.IsQueued && !draft.SendAccepted));
+        if (!TryApplyDraftSnapshot(version, drafts)) return;
         await RefreshBusyActionsAsync();
         RebuildVisibleDrafts();
     }
 
+    private bool TryApplyDraftSnapshot(int version, IReadOnlyList<LocalDraft> drafts)
+    {
+        if (version != Volatile.Read(ref _draftRefreshVersion)) return false;
+        Replace(Drafts, drafts.Where(static draft => !draft.IsQueued));
+        Replace(Outbox, drafts.Where(static draft => draft.IsQueued && !draft.SendAccepted));
+        return true;
+    }
+
     private async Task PrimeNewMailNotificationsAsync()
     {
         if (_store is null)
diff --git a/tests/BetterMail.Tests/MainWindowViewModelTests.cs b/tests/BetterMail.Tests/MainWindowViewModelTests.cs
index cdc5507..90efc6f 100644
--- a/tests/BetterMail.Tests/MainWindowViewModelTests.cs
+++ b/tests/BetterMail.Tests/MainWindowViewModelTests.cs
@@ -123,11 +123,15 @@ public async Task DraftQuickDeletionDoesNotWaitForOtherDraftsToSync()
             var second = first with { Id = "second", ProviderDraftId = "remote-second" };
             await store.SaveLocalDraftAsync(first, token); await store.SaveLocalDraftAsync(second, token);
             vm.Drafts.Add(first); vm.Drafts.Add(second);
+            // Model a draft snapshot captured before deletion but delivered after both deletions.
+            var staleVersion = (int)typeof(MainWindowViewModel).GetField("_draftRefreshVersion", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic)!.GetValue(vm)!;
             var deleting = vm.DeleteDraftQuickAsync(first);
             Assert.True(vm.IsDraftDeletionPending(first));
             await deleting.WaitAsync(TimeSpan.FromSeconds(5), token);
             await vm.DeleteDraftQuickAsync(second).WaitAsync(TimeSpan.FromSeconds(5), token);
             Assert.False(provider.DeleteRelease.Task.IsCompleted);
+            var applied = (bool)typeof(MainWindowViewModel).GetMethod("TryApplyDraftSnapshot", System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.NonPublic)!.Invoke(vm, [staleVersion, new LocalDraft[] { first, second }])!;
+            Assert.False(applied);
             Assert.DoesNotContain(vm.Drafts, draft => draft.Id == first.Id || draft.Id == second.Id);
             Assert.True(await store.IsDraftPendingDeletionAsync(first.Id, token));
             Assert.True(await store.IsDraftPendingDeletionAsync(second.Id, token));