added undoLastMove

OOP_2B1_Project/src/backend/Board.java

@@ -1,6 +1,7 @@
 package backend;
 
 import java.util.ArrayList;
+import java.util.LinkedList;
 
 public class Board {
 
@@ -22,6 +23,10 @@ private Integer selectedY = null;
 
 private ArrayList<int[]> highlightedPositions = new ArrayList<>();
 
+private LinkedList<ArrayList<Piece>> boardHistory = new LinkedList<>();
+
+
+
 
 
 	public Board(int colNum, int lineNum) {
@@ -162,12 +167,11 @@ private ArrayList<int[]> highlightedPositions = new ArrayList<>();
 	                if (pieceAtDestination == null || 
 	                    pieceAtDestination.isWhite() != pieceToMove.isWhite()) {
 	                    
-	                  
+	                	saveStateToHistory();
 	                    if (pieceAtDestination != null) {
 	                        pieces.remove(pieceAtDestination);
 	                    }
 	                    
-	                    
 	                    pieces.remove(pieceToMove);
 	                    pieces.add(new Piece(pieceToMove.isWhite(), pieceToMove.getType(), x, y));
 	                    
@@ -187,7 +191,20 @@ private ArrayList<int[]> highlightedPositions = new ArrayList<>();
 	        
 	    }
 	    
-	
+	private void saveStateToHistory() {
+		ArrayList<Piece> clonedList = new ArrayList<>();
+		for(int i =0; i<pieces.size();i++) {
+			Piece pieceToCopy = pieces.get(i);
+			Piece copy = new Piece(
+					pieceToCopy.isWhite(), 
+					pieceToCopy.getType(), 
+					pieceToCopy.getX(), 
+					pieceToCopy.getY());
+					
+			clonedList.add(copy);
+		}
+        boardHistory.add(clonedList);
+	}
 
 	
 	private Piece getPieceAt(int x, int y) {
@@ -260,8 +277,9 @@ private ArrayList<int[]> highlightedPositions = new ArrayList<>();
 	}
 
 	public void undoLastMove() {
-		//TODO
-		
+	   
+	    pieces = boardHistory.getLast();
+	    boardHistory.removeLast();
 	}
 
 	public Board(Board board) {

OOP_2B1_Project/testboard

@@ -1,9 +1,9 @@
-WR,WN,WB,WQ,WK,WB,WN,WR
+,WN,WB,WQ,WK,WB,,WR
 WP,WP,WP,WP,WP,WP,WP,WP
 ,,,,,,,
-,,BK,,,,,
 ,,,,,,,
-,,,,,,,
-BP,BP,BP,BP,,BP,BP,BP
-BR,BN,BB,,BQ,BB,BN,BR
+,,WR,BP,,WN,,
+,,BN,,,,,
+BP,BP,BP,,BP,BP,BP,BP
+BR,,BB,BK,BQ,BB,BN,BR
 W