Added move generation

+ Methods for generating legal and pseudolegal moves in Piece
+ Implementations of move generation for every piece
+ Highlighting of available moves for the selected piece in BoardPanel
- Split up the move method in Board to move and attemptMove

src/dev/kske/chess/Board.java

@@ -32,28 +32,27 @@ public class Board {
 	private List<GameEventListener> gameEventListeners;
 
 	public Board() {
-		boardArr		= new Piece[8][8];
-		kingPos	= new HashMap<>();
+		boardArr			= new Piece[8][8];
+		kingPos				= new HashMap<>();
 		gameEventListeners	= new ArrayList<>();
 		initializeDefaultPositions();
 	}
 
-	public boolean move(int xPos, int yPos, int xDest, int yDest) {
-		return move(new Move(xPos, yPos, xDest, yDest));
-	}
-
-	public boolean move(Move move) {
+	/**
+	 * Moves a piece across the board if the move is legal.
+	 * 
+	 * @param move The move to execute
+	 * @return {@code true}, if the attempted move was legal and thus executed
+	 */
+	public boolean attemptMove(Move move) {
 		Piece piece = getPos(move);
 		if (piece == null || !piece.isValidMove(move)) return false;
 		else {
-			// Move piece
-			// Save destination piece for possible canceling of the move
-			Piece capturePiece = getDest(move);
-			setDest(move, getPos(move));
-			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);
+			/*
+			 * Move piece
+			 * Save destination piece for possible canceling of the move
+			 */
+			Piece capturePiece = move(move);
 
 			// Revert move if it caused a check for its team
 			if (checkCheck(piece.getColor())) {
@@ -64,13 +63,30 @@ public class Board {
 			// TODO: detecting checkmate
 			// Check for check on the opposite team
 			Color oppositeColor = piece.getColor() == Color.WHITE ? Color.BLACK : Color.WHITE;
-			if (checkCheck(oppositeColor))
-				notifyListeners(new GameEvent(this, GameEventType.CHECK, oppositeColor));
+			if (checkCheck(oppositeColor)) notifyListeners(new GameEvent(this, GameEventType.CHECK, oppositeColor));
 
 			return true;
 		}
 	}
 
+	/**
+	 * Moves a piece across the board without checking if the move is legal.
+	 * 
+	 * @param move The move to execute
+	 * @return The captures piece, or null if the move's destination was empty
+	 */
+	public Piece move(Move move) {
+		Piece	piece			= getPos(move);
+		Piece	capturePiece	= getDest(move);
+		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;
+	}
+
 	/**
 	 * Reverts a move.
 	 * 
@@ -86,6 +102,25 @@ public class Board {
 		if (getPos(move).getType() == Type.KING) kingPos.put(getPos(move).getColor(), move.pos);
 	}
 
+	/**
+	 * Generated every legal move for one color
+	 * 
+	 * @param color The color to generate the moves for
+	 * @return A list of all legal moves
+	 */
+	public List<Move> getMoves(Color color) {
+		List<Move> moves = new ArrayList<>();
+		for (int i = 0; i < 8; i++)
+			for (int j = 0; j < 8; j++)
+				if (boardArr[i][j] != null && boardArr[i][j].getColor() == color)
+					moves.addAll(boardArr[i][j].getMoves(new Position(i, j)));
+		return moves;
+	}
+
+	public List<Move> getMoves(Position pos) {
+		return get(pos).getMoves(pos);
+	}
+
 	public boolean checkCheck(Color color) {
 		for (int i = 0; i < 8; i++)
 			for (int j = 0; j < 8; j++)

src/dev/kske/chess/BoardPanel.java

@@ -3,11 +3,12 @@ package dev.kske.chess;
 import java.awt.Color;
 import java.awt.Dimension;
 import java.awt.Graphics;
-import java.awt.Point;
 import java.awt.event.ComponentAdapter;
 import java.awt.event.ComponentEvent;
 import java.awt.event.MouseAdapter;
 import java.awt.event.MouseEvent;
+import java.util.ArrayList;
+import java.util.List;
 
 import javax.swing.JOptionPane;
 import javax.swing.JPanel;
@@ -32,12 +33,16 @@ public class BoardPanel extends JPanel implements GameEventListener {
 	private int		tileSize;
 	private Board	board;
 
+	private List<Move> displayMoves;
+
 	public BoardPanel(Board board) {
 		this();
 		setBoard(board);
 	}
 
 	public BoardPanel() {
+		displayMoves = new ArrayList<>();
+
 		/*
 		 * Add a component listener for adjusting the tile size on resizing.
 		 * The size of the board is assumed to be 8x8, as well as the both the board and
@@ -57,16 +62,26 @@ public class BoardPanel extends JPanel implements GameEventListener {
 		// Add a mouse adapter for testing piece movement
 		addMouseListener(new MouseAdapter() {
 
-			private Point src;
+			private Position pos;
 
 			@Override
 			public void mousePressed(MouseEvent evt) {
-				if (src == null) src = evt.getPoint();
-				else {
-					Point dest = evt.getPoint();
-					board.move(src.x / tileSize, src.y / tileSize, dest.x / tileSize, dest.y / tileSize);
-					repaint();
-					src = null;
+				if (pos == null) {
+					pos = new Position(evt.getPoint().x / tileSize, evt.getPoint().y / tileSize);
+
+					if (board.get(pos) != null) {
+						displayMoves.clear();
+						displayMoves.addAll(board.getMoves(pos));
+						repaint();
+					}
+				} else {
+					Position dest = new Position(evt.getPoint().x / tileSize, evt.getPoint().y / tileSize);
+
+					if (board.attemptMove(new Move(pos, dest))) {
+						displayMoves.clear();
+						repaint();
+					}
+					pos = null;
 				}
 			}
 		});
@@ -89,6 +104,17 @@ public class BoardPanel extends JPanel implements GameEventListener {
 			for (int j = 0; j < 8; j++)
 				if (board.getBoardArr()[i][j] != null) g.drawImage(TextureUtil
 					.getPieceTexture(board.getBoardArr()[i][j]), i * tileSize, j * tileSize, this);
+
+		// Draw possible moves if a piece was selected
+		if (!displayMoves.isEmpty()) {
+			g.setColor(Color.green);
+			int radius = tileSize / 4;
+			for (Move move : displayMoves)
+				g.fillOval(move.dest.x * tileSize + tileSize / 2 - radius / 2,
+						move.dest.y * tileSize + tileSize / 2 - radius / 2,
+						radius,
+						radius);
+		}
 	}
 
 	@Override

src/dev/kske/chess/Move.java

@@ -29,4 +29,9 @@ public class Move {
 	public boolean isVertical() { return xDist == 0; }
 
 	public boolean isDiagonal() { return xDist == yDist; }
+
+	@Override
+	public String toString() {
+		return String.format("%s -> %s", pos, dest);
+	}
 }

src/dev/kske/chess/Position.java

@@ -14,4 +14,9 @@ public class Position {
 		this.x	= x;
 		this.y	= y;
 	}
+
+	@Override
+	public String toString() {
+		return String.format("[%d, %d]", x, y);
+	}
 }

src/dev/kske/chess/piece/Bishop.java

@@ -1,7 +1,11 @@
 package dev.kske.chess.piece;
 
+import java.util.ArrayList;
+import java.util.List;
+
 import dev.kske.chess.Board;
 import dev.kske.chess.Move;
+import dev.kske.chess.Position;
 
 /**
  * Project: <strong>Chess</strong><br>
@@ -28,6 +32,48 @@ public class Bishop extends Piece {
 		return checkDestination(move);
 	}
 
+	@Override
+	protected List<Move> getPseudolegalMoves(Position pos) {
+		List<Move> moves = new ArrayList<>();
+
+		// Diagonal moves to the lower right
+		for (int i = pos.x + 1, j = pos.y + 1; i < 8 && j < 8; i++, j++) {
+			Move move = new Move(pos, new Position(i, j));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+
+		// Diagonal moves to the lower left
+		for (int i = pos.x - 1, j = pos.y + 1; i >= 0 && j < 8; i--, j++) {
+			Move move = new Move(pos, new Position(i, j));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+
+		// Diagonal moves to the upper right
+		for (int i = pos.x + 1, j = pos.y - 1; i < 8 && j >= 0; i++, j--) {
+			Move move = new Move(pos, new Position(i, j));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+
+		// Diagonal moves to the upper left
+		for (int i = pos.x - 1, j = pos.y - 1; i >= 0 && j >= 0; i--, j--) {
+			Move move = new Move(pos, new Position(i, j));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+		return moves;
+	}
+
 	@Override
 	public Type getType() { return Type.BISHOP; }
 }

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

@@ -1,7 +1,11 @@
 package dev.kske.chess.piece;
 
+import java.util.ArrayList;
+import java.util.List;
+
 import dev.kske.chess.Board;
 import dev.kske.chess.Move;
+import dev.kske.chess.Position;
 
 /**
  * Project: <strong>Chess</strong><br>
@@ -20,6 +24,21 @@ public class King extends Piece {
 		return move.xDist <= 1 && move.yDist <= 1 && isFreePath(move);
 	}
 
+	@Override
+	protected List<Move> getPseudolegalMoves(Position pos) {
+		List<Move> moves = new ArrayList<>();
+		for (int i = Math.max(0, pos.x - 1); i < Math.min(8, pos.x + 2); i++)
+			for (int j = Math.max(0, pos.y - 1); j < Math.min(8, pos.y + 2); j++)
+				if (i != pos.x || j != pos.y) {
+					Move move = new Move(pos, new Position(i, j));
+					if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+						moves.add(move);
+						if (board.getDest(move) != null) break;
+					}
+				}
+		return moves;
+	}
+
 	@Override
 	public Type getType() { return Type.KING; }
 }

src/dev/kske/chess/piece/Knight.java

@@ -1,7 +1,11 @@
 package dev.kske.chess.piece;
 
+import java.util.ArrayList;
+import java.util.List;
+
 import dev.kske.chess.Board;
 import dev.kske.chess.Move;
+import dev.kske.chess.Position;
 
 /**
  * Project: <strong>Chess</strong><br>
@@ -20,6 +24,27 @@ public class Knight extends Piece {
 		return Math.abs(move.xDist - move.yDist) == 1 && move.xDist != 0 && move.yDist != 0 && isFreePath(move);
 	}
 
+	private void checkAndInsertMove(List<Move> moves, Position pos, int offsetX, int offsetY) {
+		if (pos.x + offsetX >= 0 && pos.x + offsetX < 8 && pos.y + offsetY >= 0 && pos.y + offsetY < 8) {
+			Move move = new Move(pos, new Position(pos.x + offsetX, pos.y + offsetY));
+			if (checkDestination(move)) moves.add(move);
+		}
+	}
+
+	@Override
+	protected List<Move> getPseudolegalMoves(Position pos) {
+		List<Move> moves = new ArrayList<>();
+		checkAndInsertMove(moves, pos, -2, 1);
+		checkAndInsertMove(moves, pos, -1, 2);
+		checkAndInsertMove(moves, pos, 1, 2);
+		checkAndInsertMove(moves, pos, 2, 1);
+		checkAndInsertMove(moves, pos, -2, -1);
+		checkAndInsertMove(moves, pos, -1, -2);
+		checkAndInsertMove(moves, pos, 1, -2);
+		checkAndInsertMove(moves, pos, 2, -1);
+		return moves;
+	}
+
 	@Override
 	public Type getType() { return Type.KNIGHT; }
 }

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

@@ -1,7 +1,11 @@
 package dev.kske.chess.piece;
 
+import java.util.ArrayList;
+import java.util.List;
+
 import dev.kske.chess.Board;
 import dev.kske.chess.Move;
+import dev.kske.chess.Position;
 
 /**
  * Project: <strong>Chess</strong><br>
@@ -37,6 +41,38 @@ public class Pawn extends Piece {
 		else return board.getDest(move) != null && board.getDest(move).getColor() != getColor();
 	}
 
+	@Override
+	protected List<Move> getPseudolegalMoves(Position pos) {
+		List<Move> moves = new ArrayList<>();
+
+		int sign = getColor() == Color.WHITE ? -1 : 1;
+
+		// Strafe left
+		if (pos.x > 0) {
+			Move move = new Move(pos, new Position(pos.x - 1, pos.y + sign));
+			if (isFreePath(move)) moves.add(move);
+		}
+
+		// Strafe right
+		if (pos.x < 7) {
+			Move move = new Move(pos, new Position(pos.x + 1, pos.y + sign));
+			if (isFreePath(move)) moves.add(move);
+		}
+
+		// Step forward
+		if (sign == 1 && pos.y < 7 || sign == -1 && pos.y > 0) {
+			Move move = new Move(pos, new Position(pos.x, pos.y + sign));
+			if (isFreePath(move)) moves.add(move);
+		}
+
+		// Double step forward
+		if (sign == 1 && pos.y == 1 || sign == -1 && pos.y == 6) {
+			Move move = new Move(pos, new Position(pos.x, pos.y + 2 * sign));
+			if (isFreePath(move)) moves.add(move);
+		}
+		return moves;
+	}
+
 	@Override
 	public Type getType() { return Type.PAWN; }
 }

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

@@ -1,7 +1,11 @@
 package dev.kske.chess.piece;
 
+import java.util.Iterator;
+import java.util.List;
+
 import dev.kske.chess.Board;
 import dev.kske.chess.Move;
+import dev.kske.chess.Position;
 
 /**
  * Project: <strong>Chess</strong><br>
@@ -19,6 +23,20 @@ public abstract class Piece {
 		this.board	= board;
 	}
 
+	public List<Move> getMoves(Position pos) {
+		List<Move> moves = getPseudolegalMoves(pos);
+		for (Iterator<Move> iterator = moves.iterator(); iterator.hasNext();) {
+			Move	move			= iterator.next();
+			Piece	capturePiece	= board.move(move);
+			if (board.checkCheck(getColor()))
+				iterator.remove();
+			board.revert(move, capturePiece);
+		}
+		return moves;
+	}
+
+	protected abstract List<Move> getPseudolegalMoves(Position pos);
+
 	public abstract boolean isValidMove(Move move);
 
 	protected boolean isFreePath(Move move) {
@@ -47,5 +65,9 @@ public abstract class Piece {
 
 	public static enum Color {
 		WHITE, BLACK;
+
+		public Color opposite() {
+			return this == WHITE ? BLACK : WHITE;
+		}
 	}
 }

src/dev/kske/chess/piece/Queen.java

@@ -1,7 +1,11 @@
 package dev.kske.chess.piece;
 
+import java.util.ArrayList;
+import java.util.List;
+
 import dev.kske.chess.Board;
 import dev.kske.chess.Move;
+import dev.kske.chess.Position;
 
 /**
  * Project: <strong>Chess</strong><br>
@@ -36,6 +40,84 @@ public class Queen extends Piece {
 		return checkDestination(move);
 	}
 
+	@Override
+	protected List<Move> getPseudolegalMoves(Position pos) {
+		List<Move> moves = new ArrayList<>();
+
+		// Horizontal moves to the right
+		for (int i = pos.x + 1; i < 8; i++) {
+			Move move = new Move(pos, new Position(i, pos.y));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+
+		// Horizontal moves to the left
+		for (int i = pos.x - 1; i >= 0; i--) {
+			Move move = new Move(pos, new Position(i, pos.y));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+
+		// Vertical moves to the top
+		for (int i = pos.y - 1; i >= 0; i--) {
+			Move move = new Move(pos, new Position(pos.x, i));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+
+		// Vertical moves to the bottom
+		for (int i = pos.y + 1; i < 8; i++) {
+			Move move = new Move(pos, new Position(pos.x, i));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+
+		// Diagonal moves to the lower right
+		for (int i = pos.x + 1, j = pos.y + 1; i < 8 && j < 8; i++, j++) {
+			Move move = new Move(pos, new Position(i, j));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+
+		// Diagonal moves to the lower left
+		for (int i = pos.x - 1, j = pos.y + 1; i >= 0 && j < 8; i--, j++) {
+			Move move = new Move(pos, new Position(i, j));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+
+		// Diagonal moves to the upper right
+		for (int i = pos.x + 1, j = pos.y - 1; i < 8 && j >= 0; i++, j--) {
+			Move move = new Move(pos, new Position(i, j));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+
+		// Diagonal moves to the upper left
+		for (int i = pos.x - 1, j = pos.y - 1; i >= 0 && j >= 0; i--, j--) {
+			Move move = new Move(pos, new Position(i, j));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+		return moves;
+	}
+
 	@Override
 	public Type getType() { return Type.QUEEN; }
 }

src/dev/kske/chess/piece/Rook.java

@@ -1,7 +1,11 @@
 package dev.kske.chess.piece;
 
+import java.util.ArrayList;
+import java.util.List;
+
 import dev.kske.chess.Board;
 import dev.kske.chess.Move;
+import dev.kske.chess.Position;
 
 /**
  * Project: <strong>Chess</strong><br>
@@ -32,6 +36,48 @@ public class Rook extends Piece {
 		return checkDestination(move);
 	}
 
+	@Override
+	protected List<Move> getPseudolegalMoves(Position pos) {
+		List<Move> moves = new ArrayList<>();
+
+		// Horizontal moves to the right
+		for (int i = pos.x + 1; i < 8; i++) {
+			Move move = new Move(pos, new Position(i, pos.y));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+
+		// Horizontal moves to the left
+		for (int i = pos.x - 1; i >= 0; i--) {
+			Move move = new Move(pos, new Position(i, pos.y));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+
+		// Vertical moves to the top
+		for (int i = pos.y - 1; i >= 0; i--) {
+			Move move = new Move(pos, new Position(pos.x, i));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+
+		// Vertical moves to the bottom
+		for (int i = pos.y + 1; i < 8; i++) {
+			Move move = new Move(pos, new Position(pos.x, i));
+			if (board.getDest(move) == null || board.getDest(move).getColor() != getColor()) {
+				moves.add(move);
+				if (board.getDest(move) != null) break;
+			} else break;
+		}
+		return moves;
+	}
+
 	@Override
 	public Type getType() { return Type.ROOK; }
 }