Fix dragging songs around and scratch pad header

Author: MattEqualsCoder

MSUScripter/Services/ControlServices/MsuProjectWindowService.cs

@@ -840,21 +840,18 @@ private void HandleDragged(MsuProjectWindowViewModelTreeData from, MsuProjectWin
 
         if (currentParent == destinationParent)
         {
-            var currentSongIndex = destinationParent.ChildTreeData.IndexOf(from);
-            var destinationTreeIndex = _viewModel.TreeItems.IndexOf(to) + 1;
-            if (currentSongIndex < destinationIndex)
-            {
-                destinationTreeIndex--;
-                destinationIndex--;
-            }
+            var dictionary = destinationParent.ChildTreeData.ToDictionary(x => x.SongInfo!, x => x);
+            destinationParent.ChildTreeData.Clear();
+            var destinationParentIndex = _viewModel.TreeItems.IndexOf(destinationParent);
 
-            destinationParent.ChildTreeData.Remove(from);
-            destinationParent.ChildTreeData.Insert(destinationIndex, from);
-            _viewModel.TreeItems.Remove(from);
-            _viewModel.TreeItems.Insert(destinationTreeIndex, from);
-            for (var i = 0; i < destinationParent.ChildTreeData.Count; i++)
+            for (var i = 0; i < destinationTrack.Songs.Count; i++)
             {
-                destinationParent.ChildTreeData[i].SortIndex = destinationParent.SortIndex + i + 1;
+                var song = destinationTrack.Songs[i];
+                var songTreeData = dictionary[song];
+                destinationParent.ChildTreeData.Add(songTreeData);
+                _viewModel.TreeItems.Remove(songTreeData);
+                _viewModel.TreeItems.Insert(destinationParentIndex + i + 1, songTreeData);
+                songTreeData.SortIndex = destinationParent.SortIndex + i + 1;
             }
 
             _viewModel.MsuSongViewModel.UpdateViewModel(_project, destinationTrack, from.SongInfo, from);
@@ -863,6 +860,7 @@ private void HandleDragged(MsuProjectWindowViewModelTreeData from, MsuProjectWin
         else
         {
             var newTreeData = from;
+            var fromSongInfo = from.SongInfo;
 
             foreach (var previousTree in currentParent.ChildTreeData.Concat(destinationParent.ChildTreeData))
             {
@@ -940,7 +938,7 @@ private void HandleDragged(MsuProjectWindowViewModelTreeData from, MsuProjectWin
                         SongInfo = song,
                     };
 
-                    if (song == from.SongInfo)
+                    if (song == fromSongInfo)
                     {
                         newTreeData = songTreeData;
                     }
@@ -960,7 +958,7 @@ private void HandleDragged(MsuProjectWindowViewModelTreeData from, MsuProjectWin
                 destinationParent.ToggleAsParent(true, false);
             }
 
-            _viewModel.MsuSongViewModel.UpdateViewModel(_project, destinationTrack, from.SongInfo, newTreeData);
+            _viewModel.MsuSongViewModel.UpdateViewModel(_project, destinationTrack, fromSongInfo, newTreeData);
             _viewModel.SelectedTreeItem = newTreeData;
         }
 

MSUScripter/ViewModels/MsuSongOuterPanelViewModel.cs

@@ -60,11 +60,13 @@ void OnPropertyChanged(object? sender, PropertyChangedEventArgs e)
 
     public void UpdateViewModel(MsuProject project, MsuTrackInfo trackInfo, MsuSongInfo? songInfo, MsuProjectWindowViewModelTreeData treeData)
     {
-        var altText = trackInfo.Songs.Count <= 1 || songInfo == null
+        var altText = trackInfo.TrackNumber == 9999
             ? ""
-            : songInfo.IsAlt
-                ? " - Alt Song #" + trackInfo.Songs.IndexOf(songInfo)
-                : " - Primary Song";
+            : trackInfo.Songs.Count <= 1 || songInfo == null
+                ? ""
+                : songInfo.IsAlt
+                    ? " - Alt Song #" + trackInfo.Songs.IndexOf(songInfo)
+                    : " - Primary Song";
         var trackInfoNumber = trackInfo.TrackNumber != 9999 ? $"#{trackInfo.TrackNumber} " : string.Empty;
         Project = project;
         TrackInfo = trackInfo;