handling the new class special moves with the new parameters

src/backend/Board.java

@@ -447,7 +447,7 @@ public class Board {
 	    return x >= 0 && x < width && y >= 0 && y < height;
 	}
 
-	private boolean isEmpty(int x, int y) {
+	public boolean isEmpty(int x, int y) {
 	    return isValidPosition(x, y) && board[x][y] == null;
 	}
 
@@ -459,6 +459,32 @@ public class Board {
 	    return isValidPosition(x, y) && board[x][y] != null && board[x][y].isWhite() == isWhite;
 	}
 	
+	public Piece getPieceAt(int x, int y) {
+	    if (!isValidPosition(x, y)) return null;
+	    return board[x][y];
+	}
+
+	public void removePieceAt(int x, int y) {
+	    if (isValidPosition(x, y)) board[x][y] = null;
+	}
+
+	public void setEnPassantCol(int col) {
+	    this.enPassantCol = col;
+	}
+
+	public void setEnPassantRow(int row) {
+	    this.enPassantRow = row;
+	}
+
+	public int getEnPassantCol() {
+	    return this.enPassantCol;
+	}
+
+	public int getEnPassantRow() {
+	    return this.enPassantRow;
+	}
+
+
 	
 	public void undoLastMove() {
 	    if (!undoStack.isEmpty()) {
@@ -497,46 +523,34 @@ public class Board {
 	    // Save current state before move for undo
 	    undoStack.push(toFileRep());
 	    
-	    // existing move logic
 	    Piece piece = board[move.getFromX()][move.getFromY()];
+	    
+	    // Handle en passant capture
+	    if (SpecialMoves.isEnPassant(this, move)) {
+	        Piece capturedPawn = board[move.getToX()][move.getFromY()];
+	        move.setCapturedPiece(capturedPawn);
+	        SpecialMoves.handleEnPassant(this, move);
+	    }
+	    
+	    // Move the piece
 	    board[move.getToX()][move.getToY()] = piece;
 	    board[move.getFromX()][move.getFromY()] = null;
 	    piece.x = move.getToX();
 	    piece.y = move.getToY();
 	    
-	 // Reset en passant tracking at the start of each move
-	    enPassantCol = -1;
-	    enPassantRow = -1;
-	    
-	 // Check if this is a pawn making a double move
-	    if (piece.getType() == PieceType.Pawn && 
-	        Math.abs(move.getFromY() - move.getToY()) == 2) {
-	        enPassantCol = move.getToX();
-	        enPassantRow = (move.getFromY() + move.getToY()) / 2; // Middle square
-	    }
+	    // Update en passant tracking
+	    SpecialMoves.updateEnPassantTracking(this, move, piece);
 	    
+	    // Handle pawn promotion
 	    if (piece.getType() == PieceType.Pawn && 
 	        (piece.getY() == 0 || piece.getY() == height - 1)) {
-	            board[piece.getX()][piece.getY()] = promotePawn(piece.isWhite(), piece.getX(), piece.getY());
-	        }
-	    
-	 // Handle en passant capture
-	    if (piece.getType() == PieceType.Pawn && 
-	    	    move.getToX() != move.getFromX() && 
-	    	    board[move.getToX()][move.getToY()] == null) {
-	    	    // This is a diagonal pawn move to an empty square - must be en passant
-	    	    
-	    	    // Capture the pawn
-	    	    Piece capturedPawn = board[move.getToX()][move.getFromY()];
-	    	    move.setCapturedPiece(capturedPawn);
-	    	    
-	    	    // Remove the captured pawn
-	    	    board[move.getToX()][move.getFromY()] = null; // not working
+	        board[piece.getX()][piece.getY()] = SpecialMoves.promotePawn(piece.isWhite(), piece.getX(), piece.getY());
 	    }
 	    
 	    turn++;
 	}
 
+	
 	//Finds the position of the king of a given color.
 	public Piece findKing(boolean isWhite) {
 	    for (int x = 0; x < width; x++) {