Refactor: Simplify sidebar drag interfaces and utilize collection Move

Author: kalmix

src/Files.App.Controls/Sidebar/ISidebarItemModel.cs

@@ -30,18 +30,10 @@ public interface ISidebarItemModel : INotifyPropertyChanged
 		/// Expansion participant that keeps the regular row appearance (icon + normal text) instead of the section-header style.
 		/// </summary>
 		bool IsLeafWithChildren => false;
-	}
-
-	public interface IDraggableSidebarItemModel : ISidebarItemModel
-	{
-		/// <summary>
-		/// The file path used for drag and drop operations
-		/// </summary>
-		string? DropPath { get; }
 
 		/// <summary>
-		/// Indicates whether the item supports reorder dropping
+		/// Indicates whether the item supports reorder dropping.
 		/// </summary>
-		bool IsReorderDropItem { get; }
+		bool IsReorderDropItem => false;
 	}
 }

src/Files.App.Controls/Sidebar/SidebarItem.cs

@@ -133,10 +133,10 @@ public void HandleItemChange()
 			UpdateExpansionState();
 			ReevaluateSelection();
 
-			if (Item is IDraggableSidebarItemModel draggableItem)
+			if (Item is not null)
 			{
-				CanDrag = IsValidDropPath(draggableItem.DropPath);
-				UseReorderDrop = !IsGroupHeader && CanDrag && draggableItem.IsReorderDropItem;
+				CanDrag = IsValidDropPath(Item.Path);
+				UseReorderDrop = !IsGroupHeader && CanDrag && Item.IsReorderDropItem;
 			}
 			else
 			{
@@ -211,7 +211,7 @@ private static bool IsValidDropPath(string? path)
 
 		private void SidebarItem_DragStarting(UIElement sender, DragStartingEventArgs args)
 		{
-			if (Item is not IDraggableSidebarItemModel draggableItem || draggableItem.DropPath is not string dragPath || !IsValidDropPath(dragPath))
+			if (Item?.Path is not string dragPath || !IsValidDropPath(dragPath))
 				return;
 
 			SafetyExtensions.IgnoreExceptions(() =>

src/Files.App/Data/Contracts/INavigationControlItem.cs

@@ -5,15 +5,13 @@
 
 namespace Files.App.Data.Contracts
 {
-	public interface INavigationControlItem : IComparable<INavigationControlItem>, INotifyPropertyChanged, IDraggableSidebarItemModel
+	public interface INavigationControlItem : IComparable<INavigationControlItem>, INotifyPropertyChanged, ISidebarItemModel
 	{
 		public new string Text { get; }
 
 		public string Path { get; }
 
-		string? IDraggableSidebarItemModel.DropPath => Path;
-
-		bool IDraggableSidebarItemModel.IsReorderDropItem => Section == SectionType.Pinned;
+		bool ISidebarItemModel.IsReorderDropItem => Section == SectionType.Pinned;
 
 		public SectionType Section { get; }
 

src/Files.App/ViewModels/UserControls/SidebarViewModel.cs

@@ -1546,9 +1546,7 @@ private async Task HandleLocationItemDroppedAsync(LocationItem locationItem, Ite
 
 							if (sourceIndex != targetIndex && targetIndex >= 0 && targetIndex < section.ChildItems.Count)
 							{
-								var item = section.ChildItems[sourceIndex];
-								section.ChildItems.RemoveAt(sourceIndex);
-								section.ChildItems.Insert(targetIndex, item);
+								section.ChildItems.Move(sourceIndex, targetIndex);
 								await PersistPinnedOrderAsync(section);
 							}
 						}