Pawn.java

package chess;

public class Pawn extends Piece {
	
	// Pawn class
	public Pawn (char file, int rank, boolean isBlack) {
		super (file, rank, isBlack);		
	}
	
	@Override
	public boolean canMove (char startFile, int startRank, char newFile, 
			int newRank, Board board) {
		int pawnDirection = (this.isBlack) ? -1 : 1;
		
		// Check for vertical, horizontal, a clear path and that the square is different from its own
		if (!isDiffSquare(startFile, startRank, newFile, newRank)) return false;
		
		if (verticalMove(startFile, startRank, newFile, newRank) &&
		        newRank - startRank == pawnDirection &&
		        board.isEmpty(newFile, newRank)) {
		        return true;
		}
		    
		    // Forward two (only if on starting rank)
		if (verticalMove(startFile, startRank, newFile, newRank) &&
		        newRank - startRank == 2 * pawnDirection && (startRank == (isBlack ? 7 : 2)) &&
		        board.isEmpty(newFile, newRank) && board.isEmpty(startFile, startRank + pawnDirection)) {
		        return true;
		}
		    
		    // Diagonal capture
		if (diagonalMove(startFile, startRank, newFile, newRank) &&
		        newRank - startRank == pawnDirection) {
		        Piece target = board.getPiece(newFile, newRank);
		        if (target != null && target.isBlack != this.isBlack) {
		            return true;
		        }
		}
		
		return false;	
	}
	public boolean attacksSquare(char startFile, int startRank, char file, int rank) {
	    int pawnDirection = (this.isBlack) ? -1 : 1;
	    return diagonalMove(startFile, startRank, file, rank) &&
	           (rank - startRank == pawnDirection);
	}
	
	@Override
	public Piece clone() {
	    return new Pawn(this.getFile(), this.getRank(), this.isBlack);
	}
	
	@Override
	public String getSymbol() {
		
		return ("P");
	}

}