DYN-5921: Clear code block edit flag on unload and focus loss (#17311)

Author: Chloepeg

src/DynamoCoreWpf/PublicAPI.Unshipped.txt

@@ -58,6 +58,7 @@ Dynamo.Wpf.Views.GuidedTour.RealTimeInfoWindow.HyperlinkUri.get -> System.Uri
 Dynamo.Wpf.Views.GuidedTour.RealTimeInfoWindow.HyperlinkUri.set -> void
 override Dynamo.PackageManager.UI.PackageManagerTabControl.OnKeyDown(System.Windows.Input.KeyEventArgs e) -> void
 override Dynamo.UI.Controls.CodeBlockEditor.OnPreviewKeyDown(System.Windows.Input.KeyEventArgs e) -> void
+override Dynamo.UI.Controls.CodeBlockEditor.OnIsKeyboardFocusWithinChanged(System.Windows.DependencyPropertyChangedEventArgs e) -> void
 override Dynamo.PackageManager.UI.PackageManagerTabControl.OnSelectionChanged(System.Windows.Controls.SelectionChangedEventArgs e) -> void
 static Dynamo.PackageManager.UI.PackageManagerTabControl.GetSuppressHomeEndWhenSelected(System.Windows.DependencyObject element) -> bool
 static Dynamo.PackageManager.UI.PackageManagerTabControl.SetSuppressHomeEndWhenSelected(System.Windows.DependencyObject element, bool value) -> void

src/DynamoCoreWpf/Views/CodeBlocks/CodeBlockEditor.cs

@@ -1,4 +1,5 @@
-using System;
+using System;
+using System.Windows;
 using Dynamo.Controls;
 using Dynamo.Core;
 using Dynamo.Graph.Nodes;
@@ -19,6 +20,11 @@ internal enum State
 
         private State state;
 
+        /// <summary>
+        /// Current editor state.
+        /// </summary>
+        internal State CurrentState => state;
+
         /// <summary>
         /// Event handler for editor state changed.
         /// </summary>
@@ -84,6 +90,22 @@ public CodeBlockEditor(NodeView nodeView): base(nodeView)
 
             WatermarkLabel.Text = Properties.Resources.WatermarkLabelText;
             stateMachine.OnStateChanged += OnEditorStateChanged;
+            nodeView.Unloaded += OnNodeViewUnloaded;
+        }
+
+        /// <summary>
+        /// Ensures graph shortcuts are restored if this editor is unloaded while still
+        /// in edit mode (e.g. node removal or workspace close). LostFocus may not commit
+        /// when <see cref="CodeCompletionEditor.IsDisposed"/> is already true.
+        /// Only clears the shared flag when this editor was the active one, so unloading
+        /// another Code Block does not re-enable shortcuts mid-edit.
+        /// </summary>
+        private void OnNodeViewUnloaded(object sender, System.Windows.RoutedEventArgs e)
+        {
+            if (stateMachine.CurrentState == EditorStateMachine.State.Editing)
+            {
+                nodeViewModel.DynamoViewModel.IsCodeBlockEditorActive = false;
+            }
         }
 
         protected override void OnEscape()
@@ -116,6 +138,21 @@ protected override void OnCommitChange()
         protected override void OnTextAreaGotFocus(object sender, System.Windows.RoutedEventArgs e)
         {
             stateMachine.Transit(EditorStateMachine.State.Editing);
+            // Ensure the flag is set even if the state machine was already Editing
+            // (e.g. keyboard focus returned after a modal dialog closed).
+            nodeViewModel.DynamoViewModel.IsCodeBlockEditorActive = true;
+        }
+
+        /// <summary>
+        /// Keeps the shared edit flag in sync with keyboard focus. Clears it when focus
+        /// leaves (e.g. dialog or AA assistant chat) and sets it again when focus returns,
+        /// including cases where TextArea GotFocus does not fire reliably.
+        /// </summary>
+        protected override void OnIsKeyboardFocusWithinChanged(DependencyPropertyChangedEventArgs e)
+        {
+            base.OnIsKeyboardFocusWithinChanged(e);
+
+            nodeViewModel.DynamoViewModel.IsCodeBlockEditorActive = IsKeyboardFocusWithin;
         }
 
         private void OnEditorStateChanged(EditorStateMachine.State state)