public void Move(int move)
{
halfMovesStack.Push(halfMoves);
IPiece p = board[MovePackHelper.GetStartSquare(move)];
if (MovePackHelper.HasCapture(move))
{
captured.Push(board[MovePackHelper.GetEndSquare(move)]);
board[MovePackHelper.GetEndSquare(move)].Capture();
ZKey ^= ZKeyForCastling[(int)CastlingStatus];
CastlingStatus ^= MovePackHelper.GetCastleMask(move);
ZKey ^= ZKeyForCastling[(int)CastlingStatus];
halfMoves = 0;
}
else
{
if (p.Type != PieceType.Pawn)
{
halfMoves++;
}
}
p.Move(move);
if (MovePackHelper.HasCastling(move))
{
DoCastling(move);
}
PromotionTo to = MovePackHelper.GetPromotion(move);
if (to != PromotionTo.None)
{
DoPromotion(p, move, to);
}
moveStack.Push(move);
if (!epTouched)
{
PlaceEnpassant(Square.Invalid);
}
epTouched = false;
if (ToMove == Side.Black)
{
movesCount++;
}
Flip();
Debug.Assert(ZKey == CalcZKey());
}
private void UndoMove(int move)
{
IPiece p = board[MovePackHelper.GetEndSquare(move)];
p.UnMove(move);
if (MovePackHelper.HasCapture(move))
{
IPiece resumed = captured.Pop();
resumed.UnCapture(MovePackHelper.GetEndSquare(move));
board[resumed.HomeSquare] = resumed;
ZKey ^= ZKeyForCastling[(int)CastlingStatus];
CastlingStatus ^= MovePackHelper.GetCastleMask(move);
ZKey ^= ZKeyForCastling[(int)CastlingStatus];
}
if (MovePackHelper.HasCastling(move))
{
UndoCastling(move);
}
PromotionTo to = MovePackHelper.GetPromotion(move);
if (to != PromotionTo.None)
{
UndoPromotion(p, move, to);
}
if (!epTouched)
{
UnplaceEnPassant();
}
epTouched = false;
if (ToMove == Side.White)
{
movesCount--;
}
halfMoves = halfMovesStack.Pop();
Flip();
Debug.Assert(ZKey == CalcZKey());
}