Working on board loading from FEN-encoded string

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

@@ -64,7 +64,7 @@ public class Board implements Cloneable {
 		kingPos			= new HashMap<>();
 		castlingRights	= new HashMap<>();
 		log				= new Log();
-		initializeDefaultPositions();
+		initDefaultPositions();
 	}
 
 	/**
@@ -327,7 +327,7 @@ public class Board implements Cloneable {
 	/**
 	 * Initialized the board array with the default chess pieces and positions.
 	 */
-	public void initializeDefaultPositions() {
+	public void initDefaultPositions() {
 		// Initialize pawns
 		for (int i = 0; i < 8; i++) {
 			boardArr[i][1]	= new Pawn(Color.BLACK, this);
@@ -383,34 +383,63 @@ public class Board implements Cloneable {
 	}
 
 	/**
-	 * @return A new instance of this class with a shallow copy of both
-	 *         {@code kingPos} and {code boardArr}
+	 * Initialized the board with a position specified in a FEN-encoded string.
+	 * 
+	 * @param fen The FEN-encoded string representing target state of the board
 	 */
-	@Override
-	public Object clone() {
-		Board board = null;
-		try {
-			board = (Board) super.clone();
-		} catch (CloneNotSupportedException ex) {
-			ex.printStackTrace();
-		}
-		board.boardArr = new Piece[8][8];
-		for (int i = 0; i < 8; i++)
-			for (int j = 0; j < 8; j++) {
-				if (boardArr[i][j] == null) continue;
-				board.boardArr[i][j]		= (Piece) boardArr[i][j].clone();
-				board.boardArr[i][j].board	= board;
+	public void initFromFEN(String fen) {
+		String[] parts = fen.split(" ");
+		log.reset();
+
+		// Piece placement (from white's perspective)
+		String[] rows = parts[0].split("/");
+		for (int i = 0; i < 8; i++) {
+			char[] places = rows[i].toCharArray();
+			for (int j = 0, k = 0; k < places.length; j++, k++) {
+				if (Character.isDigit(places[k])) {
+					for (int l = j; l < Character.digit(places[k], 10); l++, j++)
+						boardArr[j][i] = null;
+					--j;
+				}
+				else {
+					Color color = Character.isUpperCase(places[k]) ? Color.WHITE : Color.BLACK;
+					switch (Character.toLowerCase(places[k])) {
+						case 'k':
+							boardArr[j][i] = new King(color, this);
+							kingPos.put(color, new Position(j, i));
+							break;
+						case 'q':
+							boardArr[j][i] = new Queen(color, this);
+							break;
+						case 'r':
+							boardArr[j][i] = new Rook(color, this);
+							break;
+						case 'n':
+							boardArr[j][i] = new Knight(color, this);
+							break;
+						case 'b':
+							boardArr[j][i] = new Bishop(color, this);
+							break;
+						case 'p':
+							boardArr[j][i] = new Pawn(color, this);
+							break;
+						default:
+							System.err.printf("Unknown character '%c' in board declaration of FEN string '%s'%n",
+									places[k],
+									fen);
+					}
+				}
 			}
+		}
 
-		board.kingPos = new HashMap<>();
-		board.kingPos.putAll(kingPos);
-		board.log = (Log) log.clone();
+		// Active color
+		log.setActiveColor(Color.fromFirstChar(parts[1].charAt(0)));
 
-		return board;
+		// TODO: other fields, synchronize with log and game
 	}
 
 	/**
-	 * @return A FEN string representing the board
+	 * @return A FEN-encoded string representing the board
 	 */
 	public String toFEN() {
 		StringBuilder sb = new StringBuilder();
@@ -458,6 +487,7 @@ public class Board implements Cloneable {
 		// Active color
 		sb.append(" " + log.getActiveColor().firstChar());
 
+		// Castling Rights
 		sb.append(' ');
 		StringBuilder castlingSb = new StringBuilder();
 		if (castlingRights.get(Color.WHITE).get(Type.KING)) castlingSb.append('K');
@@ -469,7 +499,7 @@ public class Board implements Cloneable {
 
 		final LoggedMove lastMove = log.getLast();
 
-		// En passant availabillity
+		// En passant availability
 		sb.append(" " + (lastMove == null || lastMove.enPassant == null ? "-" : lastMove.enPassant.toSAN()));
 
 		// Halfmove clock
@@ -481,6 +511,33 @@ public class Board implements Cloneable {
 		return sb.toString();
 	}
 
+	/**
+	 * @return A new instance of this class with a shallow copy of both
+	 *         {@code kingPos} and {code boardArr}
+	 */
+	@Override
+	public Object clone() {
+		Board board = null;
+		try {
+			board = (Board) super.clone();
+		} catch (CloneNotSupportedException ex) {
+			ex.printStackTrace();
+		}
+		board.boardArr = new Piece[8][8];
+		for (int i = 0; i < 8; i++)
+			for (int j = 0; j < 8; j++) {
+				if (boardArr[i][j] == null) continue;
+				board.boardArr[i][j]		= (Piece) boardArr[i][j].clone();
+				board.boardArr[i][j].board	= board;
+			}
+
+		board.kingPos = new HashMap<>();
+		board.kingPos.putAll(kingPos);
+		board.log = (Log) log.clone();
+
+		return board;
+	}
+
 	public Piece get(Position pos) {
 		return boardArr[pos.x][pos.y];
 	}

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

@@ -69,6 +69,8 @@ public class Log implements Cloneable {
 
 	public Color getActiveColor() { return activeColor; }
 
+	public void setActiveColor(Color activeColor) { this.activeColor = activeColor; }
+
 	public List<LoggedMove> getLoggedMoves() { return moves; }
 
 	public static class LoggedMove {

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

@@ -91,12 +91,16 @@ public abstract class Piece implements Cloneable {
 	public static enum Color {
 		WHITE, BLACK;
 
-		public Color opposite() {
-			return this == WHITE ? BLACK : WHITE;
+		public static Color fromFirstChar(char c) {
+			return Character.toLowerCase(c) == 'w' ? WHITE : BLACK;
 		}
 
 		public char firstChar() {
 			return this == WHITE ? 'w' : 'b';
 		}
+
+		public Color opposite() {
+			return this == WHITE ? BLACK : WHITE;
+		}
 	}
 }

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

@@ -89,7 +89,7 @@ public class Game {
 
 	public void reset() {
 		players.values().forEach(Player::cancelMove);
-		board.initializeDefaultPositions();
+		board.initDefaultPositions();
 		boardComponent.repaint();
 		overlayComponent.clearDots();
 		overlayComponent.clearArrow();

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

@@ -82,6 +82,18 @@ public class MenuBar extends JMenuBar {
 			.setContents(new StringSelection(mainWindow.getGame().getBoard().toFEN()), null));
 		toolsMenu.add(exportFENMenuItem);
 
+		// TODO: Synchronize with game
+		JMenuItem loadFromFENMenuItem = new JMenuItem("Load board from FEN");
+		loadFromFENMenuItem.addActionListener((evt) -> {
+			mainWindow.getGame().reset();
+			mainWindow.getGame()
+			.getBoard()
+				.initFromFEN(JOptionPane.showInputDialog("Enter a FEN string: "));
+			mainWindow.getBoardPane().getBoardComponent().repaint();
+
+		});
+		toolsMenu.add(loadFromFENMenuItem);
+
 		add(toolsMenu);
 	}