Added move history and pawn promotion

+ Log class for move history
+ LoggedMove class with piece captured by the logged move
- Made move reversion easier
+ MoveType for recognizing special moves
+ MoveType determination during move generation and validation

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

@@ -5,6 +5,7 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 
+import dev.kske.chess.board.Log.LoggedMove;
 import dev.kske.chess.board.Piece.Color;
 import dev.kske.chess.board.Piece.Type;
 
@@ -18,10 +19,12 @@ public class Board implements Cloneable {
 
 	private Piece[][]				boardArr;
 	private Map<Color, Position>	kingPos;
+	private Log						log;
 
 	public Board() {
 		boardArr	= new Piece[8][8];
 		kingPos		= new HashMap<>();
+		log			= new Log();
 		initializeDefaultPositions();
 	}
 
@@ -36,11 +39,11 @@ public class Board implements Cloneable {
 		if (piece == null || !piece.isValidMove(move)) return false;
 		else {
 			// Move piece
-			Piece capturePiece = move(move);
+			move(move);
 
 			// Revert move if it caused a check for its team
 			if (checkCheck(piece.getColor())) {
-				revert(move, capturePiece);
+				revert();
 				return false;
 			}
 
@@ -54,31 +57,57 @@ public class Board implements Cloneable {
 	 * @param move The move to execute
 	 * @return The captures piece, or null if the move's destination was empty
 	 */
-	public Piece move(Move move) {
+	public void move(Move move) {
 		Piece	piece			= getPos(move);
 		Piece	capturePiece	= getDest(move);
+
+		switch (move.type) {
+			case PAWN_PROMOTION:
+				setPos(move, null);
+				// TODO: Select promotion
+				setDest(move, new Queen(piece.getColor(), this));
+				break;
+			case UNKNOWN:
+				System.err.printf("Unknown move %s found!%n", move);
+			case NORMAL:
 				setDest(move, piece);
 				setPos(move, null);
+		}
 
 		// Update the king's position if the moved piece is the king
 		if (piece.getType() == Type.KING) kingPos.put(piece.getColor(), move.dest);
 
-		return capturePiece;
+		// Update log
+		log.add(move, capturePiece);
 	}
 
 	/**
-	 * Reverts a move.
-	 * 
-	 * @param move          The move to revert
-	 * @param capturedPiece The piece that has been captured when the move has been
-	 *                      applied
+	 * Reverts the last move.
 	 */
-	public void revert(Move move, Piece capturedPiece) {
+	public void revert() {
+		LoggedMove	loggedMove		= log.getLast();
+		Move		move			= loggedMove.move;
+		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 UNKNOWN:
+				System.err.printf("Unknown move %s found!%n", move);
+			case NORMAL:
 				setPos(move, getDest(move));
 				setDest(move, capturedPiece);
+		}
 
 		// 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);
+
+		// Update log
+		log.removeLast();
 	}
 
 	/**
@@ -129,9 +158,9 @@ public class Board implements Cloneable {
 		if (!getMoves(kingPos.get(color)).isEmpty()) return false;
 		else {
 			for (Move move : getMoves(color)) {
-				Piece	capturePiece	= move(move);
+				move(move);
 				boolean check = checkCheck(color);
-				revert(move, capturePiece);
+				revert();
 				if (!check) return false;
 			}
 			return true;
@@ -139,8 +168,7 @@ public class Board implements Cloneable {
 	}
 
 	public GameState getGameEventType(Color color) {
-		return checkCheck(color)
-				? checkCheckmate(color) ? GameState.CHECKMATE : GameState.CHECK
+		return checkCheck(color) ? checkCheckmate(color) ? GameState.CHECKMATE : GameState.CHECK
 				: getMoves(color).isEmpty() ? GameState.STALEMATE : GameState.NORMAL;
 	}
 
@@ -243,6 +271,8 @@ public class Board implements Cloneable {
 		board.kingPos = new HashMap<>();
 		board.kingPos.putAll(kingPos);
 
+		board.log = (Log) log.clone();
+
 		return board;
 	}
 

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

@@ -0,0 +1,55 @@
+package dev.kske.chess.board;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Project: <strong>Chess</strong><br>
+ * File: <strong>Log.java</strong><br>
+ * Created: <strong>09.07.2019</strong><br>
+ * Author: <strong>Kai S. K. Engelbart</strong>
+ */
+public class Log implements Cloneable {
+
+	private List<LoggedMove> moves;
+
+	public Log() {
+		moves = new ArrayList<>();
+	}
+
+	public void add(Move move, Piece capturedPiece) {
+		moves.add(new LoggedMove(move, capturedPiece));
+	}
+
+	public LoggedMove getLast() {
+		return moves.get(moves.size() - 1);
+	}
+	
+	public void removeLast() {
+		if (!moves.isEmpty()) moves.remove(moves.size() - 1);
+	}
+
+	@Override
+	public Object clone() {
+		Log log = null;
+		try {
+			log = (Log) super.clone();
+		} catch (CloneNotSupportedException e) {
+			e.printStackTrace();
+		}
+		log.moves = new ArrayList<>();
+		log.moves.addAll(this.moves);
+		return log;
+	}
+
+	public static class LoggedMove {
+
+		public final Move		move;
+		public final Piece	capturedPiece;
+
+		public LoggedMove(Move move, Piece capturedPiece) {
+			this.move		= move;
+			this.capturedPiece	= capturedPiece;
+		}
+	}
+}

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

@@ -10,16 +10,22 @@ public class Move {
 
 	public final Position	pos, dest;
 	public final int		xDist, yDist, xSign, ySign;
+	public Type				type;
 
-	public Move(Position pos, Position dest) {
+	public Move(Position pos, Position dest, Type type) {
 		this.pos	= pos;
 		this.dest	= dest;
+		this.type	= type;
 		xDist		= Math.abs(dest.x - pos.x);
 		yDist		= Math.abs(dest.y - pos.y);
 		xSign		= (int) Math.signum(dest.x - pos.x);
 		ySign		= (int) Math.signum(dest.y - pos.y);
 	}
 
+	public Move(Position pos, Position dest) {
+		this(pos, dest, Type.NORMAL);
+	}
+
 	public Move(int xPos, int yPos, int xDest, int yDest) {
 		this(new Position(xPos, yPos), new Position(xDest, yDest));
 	}
@@ -34,4 +40,8 @@ public class Move {
 	public String toString() {
 		return String.format("%s -> %s", pos, dest);
 	}
+
+	public static enum Type {
+		NORMAL, PAWN_PROMOTION, CASTLING, EN_PASSANT, UNKNOWN
+	}
 }

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

@@ -17,12 +17,17 @@ public class Pawn extends Piece {
 
 	@Override
 	public boolean isValidMove(Move move) {
-		// TODO: en passant, pawn promotion
+		// TODO: en passant
 		boolean	step		= move.isVertical() && move.yDist == 1;
 		boolean	doubleStep	= move.isVertical() && move.yDist == 2;
 		boolean	strafe		= move.isDiagonal() && move.xDist == 1;
 		if (getColor() == Color.WHITE) doubleStep &= move.pos.y == 6;
 		else doubleStep &= move.pos.y == 1;
+
+		// Mark move as pawn promotion if necessary
+		if (move.ySign == 1 && move.pos.y == 6 || move.ySign == -1 && move.pos.y == 1)
+			move.type = Move.Type.PAWN_PROMOTION;
+
 		return (step ^ doubleStep ^ strafe) && move.ySign == (getColor() == Color.WHITE ? -1 : 1) && isFreePath(move);
 	}
 
@@ -43,8 +48,6 @@ public class Pawn extends Piece {
 
 		int sign = getColor() == Color.WHITE ? -1 : 1;
 
-		if (sign == -1 && pos.y == 1 || sign == 1 && pos.y == 7) return moves;
-
 		// Strafe left
 		if (pos.x > 0) {
 			Move move = new Move(pos, new Position(pos.x - 1, pos.y + sign));
@@ -68,6 +71,11 @@ public class Pawn extends Piece {
 			Move move = new Move(pos, new Position(pos.x, pos.y + 2 * sign));
 			if (isFreePath(move)) moves.add(move);
 		}
+
+		// Mark moves as pawn promotions if necessary
+		if (sign == 1 && pos.y == 6 || sign == -1 && pos.y == 1)
+			moves.parallelStream().forEach(m -> m.type = Move.Type.PAWN_PROMOTION);
+
 		return moves;
 	}
 

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

@@ -23,10 +23,10 @@ public abstract class Piece implements Cloneable {
 		List<Move> moves = getPseudolegalMoves(pos);
 		for (Iterator<Move> iterator = moves.iterator(); iterator.hasNext();) {
 			Move	move			= iterator.next();
-			Piece	capturePiece	= board.move(move);
+			board.move(move);
 			if (board.checkCheck(getColor()))
 				iterator.remove();
-			board.revert(move, capturePiece);
+			board.revert();
 		}
 		return moves;
 	}
@@ -67,7 +67,7 @@ public abstract class Piece implements Cloneable {
 	public Color getColor() { return color; }
 
 	public static enum Type {
-		KING, QUEEN, ROOK, KNIGHT, BISHOP, PAWN;
+		KING, QUEEN, ROOK, KNIGHT, BISHOP, PAWN
 	}
 
 	public static enum Color {

src/dev/kske/chess/game/ai/MoveProcessor.java

@@ -5,7 +5,6 @@ import java.util.concurrent.Callable;
 
 import dev.kske.chess.board.Board;
 import dev.kske.chess.board.Move;
-import dev.kske.chess.board.Piece;
 import dev.kske.chess.board.Piece.Color;
 
 /**
@@ -39,7 +38,7 @@ public class MoveProcessor implements Callable<ProcessingResult> {
 	private int miniMax(Board board, List<Move> moves, Color color, int depth) {
 		int bestValue = Integer.MIN_VALUE;
 		for (Move move : moves) {
-			Piece	capturePiece	= board.move(move);
+			board.move(move);
 			int		teamValue		= board.evaluate(color);
 			int		enemyValue		= board.evaluate(color.opposite());
 			int		valueChange		= teamValue - enemyValue;
@@ -52,7 +51,7 @@ public class MoveProcessor implements Callable<ProcessingResult> {
 				if (depth == 0) bestMove = move;
 			}
 
-			board.revert(move, capturePiece);
+			board.revert();
 		}
 		return bestValue;
 	}