Allow undoing overwriting designs.

Glamourer/Designs/DesignManager.cs

@@ -19,12 +19,13 @@ namespace Glamourer.Designs;
 
 public class DesignManager
 {
-    private readonly CustomizationService _customizations;
-    private readonly ItemManager          _items;
-    private readonly HumanModelList       _humans;
-    private readonly SaveService          _saveService;
-    private readonly DesignChanged        _event;
-    private readonly List<Design>         _designs = new();
+    private readonly CustomizationService         _customizations;
+    private readonly ItemManager                  _items;
+    private readonly HumanModelList               _humans;
+    private readonly SaveService                  _saveService;
+    private readonly DesignChanged                _event;
+    private readonly List<Design>                 _designs   = new();
+    private readonly Dictionary<Guid, DesignData> _undoStore = new();
 
     public IReadOnlyList<Design> Designs
         => _designs;
@@ -83,6 +84,10 @@ public class DesignManager
         _event.Invoke(DesignChanged.Type.ReloadedAll, null!);
     }
 
+    /// <summary> Whether an Undo for the given design is possible. </summary>
+    public bool CanUndo(Design? design)
+        => design != null && _undoStore.ContainsKey(design.Identifier);
+
     /// <summary> Create a new temporary design without adding it to the manager. </summary>
     public DesignBase CreateTemporary()
         => new(_items);
@@ -463,6 +468,7 @@ public class DesignManager
     /// <summary> Apply an entire design based on its appliance rules piece by piece. </summary>
     public void ApplyDesign(Design design, DesignBase other)
     {
+        _undoStore[design.Identifier] = design.DesignData;
         if (other.DoApplyWetness())
             design.DesignData.SetIsWet(other.DesignData.IsWet());
         if (other.DoApplyHatVisible())
@@ -503,6 +509,16 @@ public class DesignManager
             ChangeStain(design, EquipSlot.OffHand, other.DesignData.Stain(EquipSlot.OffHand));
     }
 
+    public void UndoDesignChange(Design design)
+    {
+        if (!_undoStore.Remove(design.Identifier, out var otherData))
+            return;
+
+        var other = CreateTemporary();
+        other.DesignData = otherData;
+        ApplyDesign(design, other);
+    }
+
     private void MigrateOldDesigns()
     {
         if (!File.Exists(_saveService.FileNames.MigrationDesignFile))

Glamourer/Gui/Tabs/DesignTab/DesignPanel.cs

@@ -84,6 +84,16 @@ public class DesignPanel
             Disabled = _selector.Selected?.WriteProtected() ?? true,
         };
 
+    private HeaderDrawer.Button UndoButton()
+        => new()
+        {
+            Description = "Undo the last change if you accidentally overwrote your design with a different one.",
+            Icon     = FontAwesomeIcon.Undo,
+            OnClick  = UndoOverwrite,
+            Visible  = _selector.Selected != null,
+            Disabled = !_manager.CanUndo(_selector.Selected),
+        };
+
     private HeaderDrawer.Button ExportToClipboardButton()
         => new()
         {
@@ -95,7 +105,7 @@ public class DesignPanel
 
     private void DrawHeader()
         => HeaderDrawer.Draw(SelectionName, 0, ImGui.GetColorU32(ImGuiCol.FrameBg),
-            2, SetFromClipboardButton(), ExportToClipboardButton(), LockButton(),
+            3, SetFromClipboardButton(), UndoButton(), ExportToClipboardButton(), LockButton(),
             HeaderDrawer.Button.IncognitoButton(_selector.IncognitoMode, v => _selector.IncognitoMode = v));
 
     private string SelectionName
@@ -411,6 +421,18 @@ public class DesignPanel
         }
     }
 
+    private void UndoOverwrite()
+    {
+        try
+        {
+            _manager.UndoDesignChange(_selector.Selected!);
+        }
+        catch (Exception ex)
+        {
+            Glamourer.Messager.NotificationMessage(ex, $"Could not undo last changes to {_selector.Selected!.Name}.", NotificationType.Error, false);
+        }
+    }
+
     private void ExportToClipboard()
     {
         try