ChessDotNet.ChessGame.ApplyMove C# (CSharp) Method

        public virtual MoveType ApplyMove(Move move, bool alreadyValidated)
        {
            ChessUtilities.ThrowIfNull(move, "move");
            if (!alreadyValidated && !IsValidMove(move))
                return MoveType.Invalid;
            MoveType type = MoveType.Move;
            Piece movingPiece = GetPieceAt(move.OriginalPosition.File, move.OriginalPosition.Rank);
            Piece capturedPiece = GetPieceAt(move.NewPosition.File, move.NewPosition.Rank);
            Piece newPiece = movingPiece;
            bool isCapture = capturedPiece != null;
            CastlingType castle = CastlingType.None;
            if (movingPiece is Pawn)
            {
                _halfMoveClock = 0;
                PositionDistance pd = new PositionDistance(move.OriginalPosition, move.NewPosition);
                if (pd.DistanceX == 1 && pd.DistanceY == 1 && GetPieceAt(move.NewPosition) == null)
                { // en passant
                    isCapture = true;
                    SetPieceAt(move.NewPosition.File, move.OriginalPosition.Rank, null);
                }
                if (move.NewPosition.Rank == (move.Player == Player.White ? 8 : 1))
                {
                    newPiece = MapPgnCharToPiece(move.Promotion.Value, move.Player);
                    type |= MoveType.Promotion;
                }
            }
            else if (movingPiece is King)
            {
                if (movingPiece.Owner == Player.White)
                    CanWhiteCastleKingSide = CanWhiteCastleQueenSide = false;
                else
                    CanBlackCastleKingSide = CanBlackCastleQueenSide = false;

                if (new PositionDistance(move.OriginalPosition, move.NewPosition).DistanceX == 2 && CastlingCanBeLegal)
                {
                    castle = ApplyCastle(move);
                    type |= MoveType.Castling;
                }
            }
            else if (movingPiece is Rook)
            {
                if (move.Player == Player.White)
                {
                    if (move.OriginalPosition.File == File.A && move.OriginalPosition.Rank == 1)
                        CanWhiteCastleQueenSide = false;
                    else if (move.OriginalPosition.File == File.H && move.OriginalPosition.Rank == 1)
                        CanWhiteCastleKingSide = false;
                }
                else
                {
                    if (move.OriginalPosition.File == File.A && move.OriginalPosition.Rank == 8)
                        CanBlackCastleQueenSide = false;
                    else if (move.OriginalPosition.File == File.H && move.OriginalPosition.Rank == 8)
                        CanBlackCastleKingSide = false;
                }
            }
            if (isCapture)
            {
                type |= MoveType.Capture;
                _halfMoveClock = 0;
                if (move.NewPosition.File == File.A && move.NewPosition.Rank == 1)
                    CanWhiteCastleQueenSide = false;
                else if (move.NewPosition.File == File.H && move.NewPosition.Rank == 1)
                    CanWhiteCastleKingSide = false;
                else if (move.NewPosition.File == File.A && move.NewPosition.Rank == 8)
                    CanBlackCastleQueenSide = false;
                else if (move.NewPosition.File == File.H && move.NewPosition.Rank == 8)
                    CanBlackCastleKingSide = false;
            }
            if (!isCapture && !(movingPiece is Pawn))
            {
                _halfMoveClock++;
                if (_halfMoveClock >= 100)
                {
                    fiftyMoves = true;
                }
                else
                {
                    fiftyMoves = false;
                }
            }
            if (move.Player == Player.Black)
            {
                _fullMoveNumber++;
            }
            SetPieceAt(move.NewPosition.File, move.NewPosition.Rank, newPiece);
            SetPieceAt(move.OriginalPosition.File, move.OriginalPosition.Rank, null);
            WhoseTurn = ChessUtilities.GetOpponentOf(move.Player);
            _moves.Add(new DetailedMove(move, movingPiece, isCapture, castle));
            return type;
        }

        public bool WouldBeInCheckAfter(Move move, Player player)
        {
            ChessUtilities.ThrowIfNull(move, nameof(move));
            var gcd = new GameCreationData();

            gcd.Board = Board;
            gcd.CanWhiteCastleKingSide  = !_whiteRookHMoved && !_whiteKingMoved;
            gcd.CanWhiteCastleQueenSide = !_whiteRookAMoved && !_whiteKingMoved;
            gcd.CanBlackCastleKingSide  = !_blackRookHMoved && !_blackKingMoved;
            gcd.CanBlackCastleQueenSide = !_blackRookAMoved && !_blackKingMoved;
            gcd.EnPassant = null;

            if (_moves.Count > 0)
            {
                var last = _moves.Last();
                if (last.Piece is Pawn && new SquareDistance(last.OriginalPosition, last.NewPosition).DistanceY == 2)
                {
                    gcd.EnPassant = new Square(last.NewPosition.File, last.Player == Player.White ? 3 : 6);
                }
            }

            gcd.HalfMoveClock  = _halfMoveClock;
            gcd.FullMoveNumber = _fullMoveNumber;

            var copy = new ChessGame(gcd);

            copy.ApplyMove(move, true);

            var status = copy.CalculateStatus(player, false);

            return(status.Event == GameEvent.Check && status.PlayerWhoCausedEvent != player);
        }