private string GetSANSourceString(Board preMoveBoard, Move move)
{
var src = BoardHelpers.GetPieceAtIndex(preMoveBoard.Occupancy, move.SourceIndex);
Debug.Assert(src.HasValue);
if (src == Piece.King)
{
return("K");
}
if (src == Piece.Pawn)
{
var source = "";
//if the move was an En Passant or a capture, return the file letter
if (move.MoveType == MoveType.EnPassant ||
move.SourceIndex.GetFile() != move.DestinationIndex.GetFile())
{
source = move.SourceIndex.IndexToFileDisplay().ToString();
}
return(source);
}
var strSrcPiece = src.Value.GetCharRepresentation().ToString().ToUpper();
var otherLikePieces = preMoveBoard.Occupancy.Occupancy(preMoveBoard.ActivePlayer, src);
var duplicateAttackerIndexes = new List <ushort>();
foreach (var attackerIndex in otherLikePieces.GetSetBits())
{
var legalMoves = Bitboard.Instance.GetLegalMoves(attackerIndex,
preMoveBoard.Occupancy, preMoveBoard.EnPassantIndex, preMoveBoard.CastlingAvailability);
var canPieceMoveToDestination = legalMoves.Any(x => x.DestinationIndex == move.DestinationIndex);
if (canPieceMoveToDestination)
{
duplicateAttackerIndexes.Add(attackerIndex);
}
}
if (duplicateAttackerIndexes.Count == 1)
{
return(strSrcPiece);
}
var duplicateFiles = duplicateAttackerIndexes.Select(x => x.GetFile()).GroupBy(x => x)
.Any(x => x.Count() > 1);
var duplicateRanks = duplicateAttackerIndexes.Select(x => x.GetRank()).GroupBy(x => x)
.Any(x => x.Count() > 1);
if (!duplicateFiles)
{
return(strSrcPiece + move.SourceIndex.IndexToFileDisplay());
}
if (!duplicateRanks)
{
return(strSrcPiece + move.SourceIndex.IndexToRankDisplay());
}
return(strSrcPiece + move.SourceIndex.ToSquareString());
}
public void GetPieceAtIndexTest(TestCase <Piece?, ushort> testCase)
{
var actual = BoardHelpers.GetPieceAtIndex(BoardHelpers.InitialBoard, testCase.TestMethodInputValue);
Assert.AreEqual(testCase.ExpectedValue, actual, testCase.Description);
}