Added castling, fixed some minor bugs

src/dev/kske/chess/board/Board.java

@@ -50,7 +50,7 @@ public class Board implements Cloneable {
 				new int[][] { new int[] { -2, -1, -1, -1, -1, -1, -1, 2 }, new int[] { -1, 0, 0, 0, 0, 0, 0, -1 },
 						new int[] { -1, 0, 1, 1, 1, 1, 0, -1 }, new int[] { -1, 1, 1, 1, 1, 1, 1, -1 },
 						new int[] { -1, 0, 1, 1, 1, 1, 0, -1 }, new int[] { -1, 1, 1, 1, 1, 1, 1, -1 },
-						new int[] { -1, 1, 0, 0, 0, 0, 1, -1 }, new int[] { -2, -1, -1, -1, -1, -1, -2 } });
+						new int[] { -1, 1, 0, 0, 0, 0, 1, -1 }, new int[] { -2, -1, -1, -1, -1, -1, -1, -2 } });
 		positionScores.put(Type.PAWN,
 				new int[][] { new int[] { 0, 0, 0, 0, 0, 0, 0, 0 }, new int[] { 5, 5, 5, 5, 5, 5, 5, 5 },
 						new int[] { 1, 1, 2, 3, 3, 2, 1, 1 }, new int[] { 0, 0, 1, 3, 3, 1, 0, 0 },
@@ -75,6 +75,9 @@ public class Board implements Cloneable {
 		Piece piece = getPos(move);
 		if (piece == null || !piece.isValidMove(move)) return false;
 		else {
+			// Set type after validation
+			if (move.type == Move.Type.UNKNOWN) move.type = Move.Type.NORMAL;
+
 			// Move piece
 			move(move);
 
@@ -104,13 +107,34 @@ public class Board implements Cloneable {
 				// TODO: Select promotion
 				setDest(move, new Queen(piece.getColor(), this));
 				break;
+			case CASTLING:
+				// Move the king
+				setDest(move, piece);
+				setPos(move, null);
+
+				// Move the rook
+				Move rookMove = move.dest.x == 6 ? new Move(7, move.pos.y, 5, move.pos.y) // Kingside
+						: new Move(0, move.pos.y, 3, move.pos.y); // Queenside
+
+				// Move the rook
+				setDest(rookMove, getPos(rookMove));
+				setPos(rookMove, null);
+
+				getDest(rookMove).incMoveCounter();
+				break;
 			case UNKNOWN:
-				System.err.printf("Unknown move %s found!%n", move);
+				System.err.printf("Move of unknown type %s found!%n", move);
 			case NORMAL:
 				setDest(move, piece);
 				setPos(move, null);
+				break;
+			default:
+				System.err.printf("Move %s of unimplemented type found!%n", move);
 		}
 
+		// Increment move counter
+		getDest(move).incMoveCounter();
+
 		// Update the king's position if the moved piece is the king
 		if (piece.getType() == Type.KING) kingPos.put(piece.getColor(), move.dest);
 
@@ -127,19 +151,38 @@ public class Board implements Cloneable {
 		Piece		capturedPiece	= loggedMove.capturedPiece;
 
 		switch (move.type) {
-			case CASTLING:
-			case EN_PASSANT:
 			case PAWN_PROMOTION:
 				setPos(move, new Pawn(getDest(move).getColor(), this));
 				setDest(move, capturedPiece);
 				break;
+			case CASTLING:
+				// Move the king
+				setPos(move, getDest(move));
+				setDest(move, null);
+
+				// Move the rook
+				Move rookMove = move.dest.x == 6 ? new Move(5, move.pos.y, 7, move.pos.y) // Kingside
+						: new Move(3, move.pos.y, 0, move.pos.y); // Queenside
+
+				// Move the rook
+				setDest(rookMove, getPos(rookMove));
+				setPos(rookMove, null);
+
+				getDest(rookMove).decMoveCounter();
+				break;
 			case UNKNOWN:
-				System.err.printf("Unknown move %s found!%n", move);
+				System.err.printf("Move of unknown type %s found!%n", move);
 			case NORMAL:
 				setPos(move, getDest(move));
 				setDest(move, capturedPiece);
+				break;
+			default:
+				System.err.printf("Move %s of unimplemented type found!%n", move);
 		}
 
+		// Decrement move counter
+		getPos(move).decMoveCounter();
+
 		// Update the king's position if the moved piece is the king
 		if (getPos(move).getType() == Type.KING) kingPos.put(getPos(move).getColor(), move.pos);
 

src/dev/kske/chess/board/King.java

@@ -17,7 +17,26 @@ public class King extends Piece {
 
 	@Override
 	public boolean isValidMove(Move move) {
-		return move.xDist <= 1 && move.yDist <= 1 && isFreePath(move);
+		// Castling
+		if (getMoveCounter() == 0 && move.xDist == 2 && move.yDist == 0) {
+
+			// Kingside
+			if (board.getBoardArr()[7][move.pos.y] != null && board.getBoardArr()[7][move.pos.y].getType() == Type.ROOK
+					&& isFreePath(new Move(new Position(5, move.pos.y), new Position(7, move.pos.y)))) {
+				move.type = Move.Type.CASTLING;
+				return true;
+			}
+
+			// Queenside
+			if (board.getBoardArr()[0][move.pos.y] != null && board.getBoardArr()[0][move.pos.y].getType() == Type.ROOK
+					&& isFreePath(new Move(new Position(1, move.pos.y), new Position(4, move.pos.y)))) {
+				move.type = Move.Type.CASTLING;
+				return true;
+			}
+
+		}
+
+		return move.xDist <= 1 && move.yDist <= 1 && checkDestination(move);
 	}
 
 	@Override
@@ -29,9 +48,33 @@ public class King extends Piece {
 					Move move = new Move(pos, new Position(i, j));
 					if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) moves.add(move);
 				}
+
+		// Castling
+		// TODO: Check attacked squares in between
+		// TODO: Castling out of check?
+		if (getMoveCounter() == 0) {
+
+			// Kingside
+			if (board.getBoardArr()[7][pos.y] != null && board.getBoardArr()[7][pos.y].getType() == Type.ROOK
+					&& isFreePath(new Move(new Position(5, pos.y), new Position(7, pos.y))))
+				moves.add(new Move(pos, new Position(6, pos.y), Move.Type.CASTLING));
+
+			// Queenside
+			if (board.getBoardArr()[0][pos.y] != null && board.getBoardArr()[0][pos.y].getType() == Type.ROOK
+					&& isFreePath(new Move(new Position(1, pos.y), new Position(4, pos.y))))
+				moves.add(new Move(pos, new Position(2, pos.y), Move.Type.CASTLING));
+		}
+
 		return moves;
 	}
 
+	@Override
+	protected boolean isFreePath(Move move) {
+		for (int i = move.pos.x, j = move.pos.y; i != move.dest.x || j != move.dest.y; i += move.xSign, j += move.ySign)
+			if (board.getBoardArr()[i][j] != null) return false;
+		return true;
+	}
+
 	@Override
 	public Type getType() { return Type.KING; }
 }

src/dev/kske/chess/board/Piece.java

@@ -11,8 +11,9 @@ import java.util.List;
  */
 public abstract class Piece implements Cloneable {
 
-	protected Color	color;
+	private final Color	color;
 	protected Board		board;
+	private int			moveCounter;
 
 	public Piece(Color color, Board board) {
 		this.color	= color;
@@ -24,8 +25,7 @@ public abstract class Piece implements Cloneable {
 		for (Iterator<Move> iterator = moves.iterator(); iterator.hasNext();) {
 			Move move = iterator.next();
 			board.move(move);
-			if (board.checkCheck(getColor()))
+			if (board.checkCheck(getColor())) iterator.remove();
-				iterator.remove();
 			board.revert();
 		}
 		return moves;
@@ -66,6 +66,16 @@ public abstract class Piece implements Cloneable {
 
 	public Color getColor() { return color; }
 
+	public int getMoveCounter() { return moveCounter; }
+
+	public void incMoveCounter() {
+		++moveCounter;
+	}
+
+	public void decMoveCounter() {
+		--moveCounter;
+	}
+
 	public static enum Type {
 		KING, QUEEN, ROOK, KNIGHT, BISHOP, PAWN
 	}

src/dev/kske/chess/game/NaturalPlayer.java

@@ -7,6 +7,7 @@ import java.util.stream.Collectors;
 
 import dev.kske.chess.board.Board;
 import dev.kske.chess.board.Move;
+import dev.kske.chess.board.Move.Type;
 import dev.kske.chess.board.Piece.Color;
 import dev.kske.chess.board.Position;
 import dev.kske.chess.ui.OverlayComponent;
@@ -49,7 +50,7 @@ public class NaturalPlayer extends Player {
 
 					overlayComponent.clearDots();
 					moveRequested = false;
-					game.onMove(NaturalPlayer.this, new Move(pos, dest));
+					game.onMove(NaturalPlayer.this, new Move(pos, dest, Type.UNKNOWN));
 					pos = null;
 				}
 			}

src/dev/kske/chess/ui/GameModeDialog.java

@@ -79,5 +79,7 @@ public class GameModeDialog extends JDialog {
 			dispose();
 		});
 		getContentPane().add(btnAI2);
+
+		setLocationRelativeTo(null);
 	}
 }

src/dev/kske/chess/ui/MainWindow.java

@@ -64,6 +64,7 @@ public class MainWindow {
 		btnRestart.addActionListener((evt) -> System.err.println("Resetting not implemented!"));
 		toolPanel.add(btnRestart);
 		mframe.pack();
+		mframe.setLocationRelativeTo(null);
 
 		// Display dialog for game mode selection
 		new GameModeDialog(boardPane).setVisible(true);