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

@@ -8,6 +8,8 @@ import java.util.Map;
 import java.util.Objects;
 
 import dev.kske.chess.board.Piece.Color;
+import dev.kske.chess.event.EventBus;
+import dev.kske.chess.event.MoveEvent;
 
 /**
  * Project: <strong>Chess</strong><br>
@@ -120,6 +122,32 @@ public class Board {
 		log.removeLast();
 	}
 
+	public void selectPreviousNode() {
+		MoveNode	moveNode	= log.getLast();
+		Move		move		= moveNode.move;
+
+		// Revert the move
+		move.revert(this, moveNode.capturedPiece);
+
+		// Select previous move node
+		log.selectPreviousNode();
+
+		// Dispatch move event
+		EventBus.getInstance().dispatch(new MoveEvent(move.invert(), getGameEventType(log.getActiveColor().opposite())));
+	}
+
+	public void selectNextNode(int index) {
+		log.selectNextNode(index);
+		MoveNode	moveNode	= log.getLast();
+		Move		move		= moveNode.move;
+
+		// Execute the next move
+		move.execute(this);
+
+		// Dispatch move event
+		EventBus.getInstance().dispatch(new MoveEvent(move, getGameEventType(log.getActiveColor().opposite())));
+	}
+
 	/**
 	 * Generated every legal move for one color
 	 *

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

@@ -44,6 +44,10 @@ public class Move {
 		board.set(dest, capturedPiece);
 	}
 	
+	public Move invert() {
+		return new Move(dest, pos);
+	}
+
 	public static Move fromLAN(String move) {
 		Position	pos		= Position.fromLAN(move.substring(0, 2));
 		Position	dest	= Position.fromLAN(move.substring(2));

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

@@ -29,7 +29,7 @@ import dev.kske.chess.ui.OverlayComponent;
  */
 public class Game {
 
-	private Map<Color, Player>	players	= new HashMap<>();
+	private Map<Color, Player>	players	= new HashMap<>(2);
 	private Board				board;
 	private OverlayComponent	overlayComponent;
 	private BoardComponent		boardComponent;

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

@@ -12,6 +12,7 @@ import javax.swing.JButton;
 import javax.swing.JComponent;
 import javax.swing.JLabel;
 import javax.swing.JList;
+import javax.swing.JOptionPane;
 import javax.swing.JPanel;
 import javax.swing.JScrollPane;
 import javax.swing.ListSelectionModel;
@@ -95,11 +96,29 @@ public class GamePane extends JComponent {
 		moveSelectionPanel.add(btnFirst);
 
 		btnPrevious = new JButton("Previous");
-		btnPrevious.setEnabled(false);
+		btnPrevious.addActionListener((evt) -> {
+			if (game != null) {
+				game.getBoard().selectPreviousNode();
+				getBoardPane().getOverlayComponent().clearArrow();
+				repaint();
+			}
+		});
 		moveSelectionPanel.add(btnPrevious);
 
 		btnNext = new JButton("Next");
-		btnNext.setEnabled(false);
+		btnNext.addActionListener((evt) -> {
+			if(game != null) {
+				int numVariations = game.getBoard().getLog().getLast().getVariations().size();
+				int index;
+				if(numVariations == 1)
+					index = 1;
+				else
+					index = Integer.parseInt(JOptionPane.showInputDialog("Enter the variation index."));
+				game.getBoard().selectNextNode(index);
+				getBoardPane().getOverlayComponent().clearArrow();
+				repaint();
+			}
+		});
 		moveSelectionPanel.add(btnNext);
 
 		btnLast = new JButton("Last");

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

@@ -26,7 +26,10 @@ public class MoveNodeRenderer extends JLabel implements ListCellRenderer<MoveNod
 	public Component getListCellRendererComponent(JList<? extends MoveNode> list, MoveNode node, int index,
 			boolean isSelected, boolean cellHasFocus) {
 		setBorder(new EmptyBorder(5, 5, 5, 5));
-		setText(node.move.toLAN());
+		
+		int numVariations = node.hasVariations() ? node.getVariations().size() : 0; 
+		setText(String.format("%s (%d)", node.move.toLAN(), numVariations));
+		
 		setBackground(isSelected ? Color.red : Color.white);
 		setOpaque(true);
 		return this;