/// <summary>
/// Some data, like En Passant right, needs resetting before a new move is applied
/// </summary>
/// <returns></returns>
public void ResetHashBeforeMove(ref ulong hash, IrrevState irrevState)
{
if (irrevState.EnPassantCapture != 0)
{
UpdateEnPassant(ref hash, irrevState.EnPassantCapture);
}
}
protected IEnumerable <Move> GenerateCastlingMoves(ulong sq)
{
IrrevState irrevState = gameState.GetIrrevState();
for (int i = 0; i <= 1; i++)
{
if (IsCastlingAllowed(irrevState, i))
{
ulong target = castlingKingTarget[i] & BitboardUtils.FIRST_RANK[gameState.Turn];
Move move = new CastlingMove(gameState, sq, target);
yield return(move);
}
}
}
public int GetKingFileScore(int pl, int file, bool rooksConnected, IrrevState irrevState)
{
int score = kingFile[file];
if (score < 0)
{
if (!irrevState.CastlingAllowed[pl, 0] && !irrevState.CastlingAllowed[pl, 1])
{
score = (int)(score * 1.5);
}
}
else if (!rooksConnected)
{
score = (int)(score * 0.2);
}
return(score);
}
public ulong GenerateHash(GameState gameState)
{
ulong hash = 0;
for (int pl = 0; pl < 2; pl++)
{
for (int i = 0; i < 6; i++)
{
int pInd = GetPieceIndex(pl, (PieceType)i);
ulong pieces = gameState.Pieces[pl, i];
while (pieces > 0)
{
int sqInd = BitboardUtils.PopLSB(ref pieces);
hash ^= piecePosBitstring[pInd, sqInd];
}
}
}
IrrevState irrevState = gameState.GetIrrevState();
for (int pl = 0; pl < 2; pl++)
{
if (!irrevState.CastlingAllowed[pl, 0])
{
DisableCastling(ref hash, pl, 0);
}
if (!irrevState.CastlingAllowed[pl, 1])
{
DisableCastling(ref hash, pl, 1);
}
}
if (irrevState.EnPassantCapture != 0)
{
UpdateEnPassant(ref hash, irrevState.EnPassantCapture);
}
return(hash);
}
protected bool IsCastlingAllowed(IrrevState irrevState, int side)
{
return(irrevState.CastlingAllowed[gameState.Turn, side] &&
(castlingEmptySquares[side] & BitboardUtils.FIRST_RANK[gameState.Turn] & gameState.FullOccupancy) == 0);
}
public void Load(string fen, GameState gameState, bool verifyValidity = false)
{
if (verifyValidity && !IsValid(fen))
{
throw new ArgumentException("Invalid FEN");
}
gameState.Reset();
IrrevState irrevState = gameState.GetIrrevState();
ulong currPos = 1;
string[] parts = fen.Split(' ');
string[] ranks = parts[0].Split('/');
for (int i = ranks.Length - 1; i >= 0; i--)
{
string rank = ranks[i];
for (int j = 0; j < rank.Length; j++)
{
char c = rank[j];
if (char.IsDigit(c))
{
int shift = (int)char.GetNumericValue(c);
currPos = currPos << shift;
}
else
{
int pl = char.IsLower(c) ? 1 : 0;
int pieceType = (int)c.ToPieceType();
gameState.Pieces[pl, pieceType] |= currPos;
gameState.Occupancy[pl] |= currPos;
currPos = currPos << 1;
}
}
}
int turn = parts[1] == "w" ? 0 : 1;
if (gameState.Turn != turn)
{
gameState.ChangeTurn();
}
if (parts[2].IndexOf('Q') < 0)
{
irrevState.CastlingAllowed[0, 0] = false;
}
if (parts[2].IndexOf('K') < 0)
{
irrevState.CastlingAllowed[0, 1] = false;
}
if (parts[2].IndexOf('q') < 0)
{
irrevState.CastlingAllowed[1, 0] = false;
}
if (parts[2].IndexOf('k') < 0)
{
irrevState.CastlingAllowed[1, 1] = false;
}
if (parts[3] != "-")
{
irrevState.EnPassantCapture = BitboardUtils.GetBitboard(parts[3].StringToPos());
}
irrevState.HalfmoveClock = int.Parse(parts[4]);
irrevState.ZobristHash = gameState.ZobristHashUtils.GenerateHash(gameState);
}
public string Convert(GameState gameState)
{
StringBuilder builder = new StringBuilder();
for (int r = 7; r >= 0; r--)
{
int emptySq = 0;
for (int f = 0; f < 8; f++)
{
int sqInd = r * 8 + f;
string piece = GetPieceBySquare(gameState, sqInd);
if (piece == null)
{
emptySq++;
}
else
{
if (emptySq > 0)
{
builder.Append(emptySq);
emptySq = 0;
}
builder.Append(piece);
}
}
if (emptySq > 0)
{
builder.Append(emptySq);
}
if (r > 0)
{
builder.Append('/');
}
}
char turn = gameState.Turn == 0 ? 'w' : 'b';
builder.Append(" " + turn + " ");
string castling = "";
IrrevState irrevState = gameState.GetIrrevState();
if (irrevState.CastlingAllowed[0, 1])
{
castling += 'K';
}
if (irrevState.CastlingAllowed[0, 0])
{
castling += 'Q';
}
if (irrevState.CastlingAllowed[1, 1])
{
castling += 'k';
}
if (irrevState.CastlingAllowed[1, 0])
{
castling += 'q';
}
if (castling == "")
{
castling = "-";
}
builder.Append(castling + " ");
string enPassant = "-";
if (irrevState.EnPassantCapture != 0)
{
enPassant = irrevState.EnPassantCapture.PosToString();
}
builder.Append(enPassant + " ");
builder.Append(irrevState.HalfmoveClock + " ");
builder.Append(gameState.GetTurnNum());
return(builder.ToString());
}
protected void SetIrrevState()
{
irrevState = gameState.GetIrrevState();
}
private IEnumerable <Move> GetRegularMovesFromSquare(ulong sq, GenerationMode generationMode)
{
ulong reversedFullOccupancy = ~gameState.FullOccupancy;
ulong to;
ulong attacks;
if (gameState.Turn == 0)
{
if (generationMode == GenerationMode.Normal)
{
to = sq << 8 & reversedFullOccupancy;
if (to != 0)
{
yield return(new Move(gameState, sq, to, pieceType));
if ((sq & BitboardUtils.SECOND_RANK[gameState.Turn]) > 0)
{
to = to << 8 & reversedFullOccupancy;
if (to != 0)
{
yield return(new Move(gameState, sq, to, pieceType));
}
}
}
}
to = sq << 7 & BitboardUtils.NOT_H_FILE;
attacks = to;
if ((to & gameState.Occupancy[1 - gameState.Turn]) != 0)
{
yield return(new Move(gameState, sq, to, pieceType));
}
to = sq << 9 & BitboardUtils.NOT_A_FILE;
attacks |= to;
if ((to & gameState.Occupancy[1 - gameState.Turn]) != 0)
{
yield return(new Move(gameState, sq, to, pieceType));
}
}
else
{
if (generationMode == GenerationMode.Normal)
{
to = sq >> 8 & reversedFullOccupancy;
if (to != 0)
{
yield return(new Move(gameState, sq, to, pieceType));
if ((sq & BitboardUtils.SECOND_RANK[gameState.Turn]) > 0)
{
to = to >> 8 & reversedFullOccupancy;
if (to != 0)
{
yield return(new Move(gameState, sq, to, pieceType));
}
}
}
}
to = sq >> 9 & BitboardUtils.NOT_H_FILE;
attacks = to;
if ((to & gameState.Occupancy[1 - gameState.Turn]) != 0)
{
yield return(new Move(gameState, sq, to, pieceType));
}
to = sq >> 7 & BitboardUtils.NOT_A_FILE;
attacks |= to;
if ((to & gameState.Occupancy[1 - gameState.Turn]) != 0)
{
yield return(new Move(gameState, sq, to, pieceType));
}
}
//En Passant
IrrevState irrevState = gameState.GetIrrevState();
if ((irrevState.EnPassantCapture & attacks) > 0)
{
yield return(new EnPassantMove(gameState, sq, irrevState.EnPassantCapture));
}
}