feat(重构): 重构棋盘和棋子的逻辑

- 重构了 ChessBoard 和 ChessPiece 类的逻辑
- 添加了新版本的 ChineseChess 库
- 删除了旧版本的 VirtualBoard 和 VirtualPiece 类
- 更新了相关的场景和脚本

Scripts/Src/ChineseChess/CCPlayer.cs

@@ -0,0 +1,117 @@
+using System;
+using System.Collections;
+using Vector2I = Vector.Vector2I;
+
+namespace ChineseChess;
+public class Player {
+	private readonly CCBoard board;
+	private readonly SelectedPiece selectedNode;
+	
+	public EventHandler<IBoard.MoveEventArgs> OnMove;
+	public bool CanMove { get; set; } = true;
+
+	public enum PlayerType {
+		Human,
+		AI
+	}
+
+	public Player(CCBoard board, PlayerType type = PlayerType.Human)
+	{
+		this.board = board;
+		this.selectedNode = new SelectedPiece(board);
+	}
+
+	public void HandleBoardPosClick(Vector2I clickPos) {
+		if (board.IsPosOutOfRange(clickPos)) return;
+		// Console.WriteLine($"VirtualBoard {clickPos} clicked");
+		IPiece clickChess = board.GetPiece(clickPos);
+
+		if (!selectedNode.HasSelected()) {
+			// Select piece
+			if (clickChess == null) {
+				// selectedNode.Clear();
+				return;
+			}
+			selectedNode.SetPos(clickPos);
+		} else if (clickChess == selectedNode.GetPiece()) {
+			// Unselect piece
+			selectedNode.Clear();
+		} else {
+			// Move piece
+			// GD.Print("default MoveFunc Move: ", selectedNode.GetPos(), "->", clickPos);
+			if (CanMove) MoveAndRecord(clickPos, selectedNode.GetPos());
+		}
+	}
+
+	public void MoveAndRecord(Vector2I toPos, Vector2I fromPos) {
+		// GD.Print($"{fromPos} move to {toPos}");
+		IPiece toChess = board.GetPiece(toPos);
+        IPiece fromChess = board.GetPiece(fromPos);
+		if (fromChess != null) fromChess.IsSelected = false;
+		
+		selectedNode.Clear();
+		if (!fromChess.CanMove(toPos)) {
+			return;
+		}
+
+		// MUST BE THERE !!! 防止删除节点后在启动回调导致错误
+		OnMove?.Invoke(this, new IBoard.MoveEventArgs { From = fromPos, To = toPos });
+
+        if (toChess != null) {
+            board.RemovePiece(toPos);
+        }
+        board.MovePiece(fromPos, toPos);
+
+		selectedNode.Clear();
+	}
+
+	public void SelectedClear() {
+		selectedNode.Clear();
+	}
+
+	public void SetAllowedPieces(ArrayList allowedPieces) {
+		selectedNode.allowedPieces = allowedPieces;
+	}
+
+	private class SelectedPiece {
+		// Called when the node enters the scene tree for the first time.
+		private Vector2I selectedNodePos = Vector2I.MaxValue;
+		private IPiece piece;
+		private readonly CCBoard board;
+		public ArrayList allowedPieces = null;
+
+		public SelectedPiece(CCBoard board) {
+			this.board = board;
+		}
+
+		public void Clear() {
+			if (selectedNodePos != Vector2I.MaxValue) {
+				selectedNodePos = Vector2I.MaxValue;
+				piece.IsSelected = false;
+			}
+			// Console.WriteLine("SelectedPiece.Clear {0}", piece);
+		}
+
+		public void SetPos(Vector2I pos) {
+			piece = board.GetPiece(pos);
+			if (allowedPieces != null && allowedPieces.Contains(piece) == false) {
+				return;
+			}
+			selectedNodePos = pos;
+			piece.IsSelected = true;
+			Console.WriteLine("SelectedPiece.SetPos {0}", piece);
+		}
+
+		public IPiece GetPiece() {
+			return piece;
+		}
+
+		public Vector2I GetPos() {
+			return selectedNodePos;
+		}
+
+		public bool HasSelected() {
+			return selectedNodePos != Vector2I.MaxValue;
+		}
+	}
+}