before deleting Rules

Gameboard.ShogiUI.Rules/Pieces/Piece.cs

@@ -0,0 +1,47 @@
+using PathFinding;
+using System.Diagnostics;
+
+namespace Gameboard.ShogiUI.Rules.Pieces
+{
+  [DebuggerDisplay("{WhichPiece} {Owner}")]
+  public abstract class Piece : IPlanarElement
+  {
+    protected MoveSet promotedMoveSet;
+    protected MoveSet moveSet;
+
+    public MoveSet MoveSet => IsPromoted ? promotedMoveSet : moveSet;
+    public abstract Piece DeepClone();
+    public WhichPiece WhichPiece { get; }
+    public WhichPlayer Owner { get; private set; }
+    public bool IsPromoted { get; private set; }
+    public bool IsUpsideDown => Owner == WhichPlayer.Player2;
+
+    public Piece(WhichPiece piece, WhichPlayer owner)
+    {
+      WhichPiece = piece;
+      Owner = owner;
+      IsPromoted = false;
+    }
+
+    public bool CanPromote => !IsPromoted
+      && WhichPiece != WhichPiece.King
+      && WhichPiece != WhichPiece.GoldGeneral;
+
+    public void ToggleOwnership()
+    {
+      Owner = Owner == WhichPlayer.Player1
+        ? WhichPlayer.Player2
+        : WhichPlayer.Player1;
+    }
+
+    public void Promote() => IsPromoted = CanPromote;
+
+    public void Demote() => IsPromoted = false;
+
+    public void Capture()
+    {
+      ToggleOwnership();
+      Demote();
+    }
+  }
+}