private Move executeMove(Square startSquare, Square endSquare) {
Move move = InvalidMove.execute();
if (isPromotionMove(startSquare, endSquare)) {
// promotion should only be performed with game.promote()!
move = InvalidMove.execute();
} else if (EnPassantMove.canBeExecuted(board, startSquare, endSquare, lastMove())) {
move = EnPassantMove.execute(board, startSquare, endSquare);
EnPassantMove enPassantMove = (EnPassantMove) move;
capturedPieces.get(enPassantMove.opposingPiece().color()).add(enPassantMove.opposingPiece());
} else if (CastlingMove.canBeExecuted(board, startSquare, endSquare)) {
move = CastlingMove.execute(board, startSquare, endSquare);
} else if (NormalMove.canBeExecuted(board, startSquare, endSquare)) {
move = NormalMove.execute(board, startSquare, endSquare);
} else if (CaptureMove.canBeExecuted(board, startSquare, endSquare)) {
move = CaptureMove.execute(board, startSquare, endSquare);
CaptureMove captureMove = (CaptureMove) move;
capturedPieces.get(captureMove.opposingPiece().color()).add(captureMove.opposingPiece());
}
if (board.inCheck(playersTurn)) {
move.undo(board);
removeCapturedPiece(move);
move = InvalidMove.execute();
}
return move;
}
public Move move(Square startSquare, Square endSquare) {
Move move = InvalidMove.execute();
if (startSquareContainsPlayersPiece(startSquare)) {
move = executeMove(startSquare, endSquare);
if (!move.moveType().equals(MoveType.INVALID)) {
moves.add(move);
changePlayersTurn();
}
}
return move;
}
private void removeCapturedPiece(Move move) {
Piece capturedPiece = null;
if (MoveType.CAPTURE.equals(move.moveType())) {
capturedPiece = ((CaptureMove) move).opposingPiece();
} else if (MoveType.EN_PASSANT.equals(move.moveType())) {
capturedPiece = ((EnPassantMove) move).opposingPiece();
} else if (MoveType.PROMOTION.equals(move.moveType())) {
capturedPiece = ((PromotionMove) move).opposingPiece();
}
if (capturedPiece != null) {
capturedPieces.get(capturedPiece.color()).remove(capturedPiece);
}
}
public Move promote(Square startSquare, Square endSquare, PieceType pieceType) {
Move move = InvalidMove.execute();
if (PromotionMove.canBeExecuted(board, startSquare, endSquare, pieceType)) {
move = PromotionMove.execute(board, startSquare, endSquare, pieceType);
}
if (MoveType.PROMOTION.equals(move.moveType())) {
if (board.inCheck(playersTurn)) {
move.undo(board);
move = InvalidMove.execute();
} else {
PromotionMove promotionMove = (PromotionMove) move;
if (promotionMove.opposingPiece() != null) {
capturedPieces
.get(promotionMove.opposingPiece().color())
.add(promotionMove.opposingPiece());
}
moves.add(move);
changePlayersTurn();
}
}
return move;
}