/// <summary>
/// Caclulate the king's legal moves
/// </summary>
/// <param name="board"></param>
/// <returns></returns>
public override ICollection <Move> calculateLegalMoves(Board board)
{
IList <Move> legalMoves = new List <Move>();
foreach (int currentCandidateOffset in CANDIDATE_MOVE_COORDINATES)
{
//Check for first column exclusion for the king
if (isFirstColumnExclusion(this.piecePosition, currentCandidateOffset) ||
isEighthColumnExclusion(this.piecePosition, currentCandidateOffset))
{
continue;
}
int candidateDestinationCoordinate = this.piecePosition + currentCandidateOffset;
if (BoardUtils.IsValidTileCoordinate(candidateDestinationCoordinate))
{
Tile candidateDestinationTile = board.getTile(candidateDestinationCoordinate);
//If the destination tile is not occupied
if (!candidateDestinationTile.isTileOccupied())
{
legalMoves.Add(new MajorMove(board, this, candidateDestinationCoordinate));
}
//If the destination tile is occupied
else
{
Piece pieceAtDestination = candidateDestinationTile.getPiece();
Alliance pieceAlliance = pieceAtDestination.getPieceAlliance();
if (this.pieceAlliance != pieceAlliance)
{
legalMoves.Add(new MajorAttackMove(board, this, candidateDestinationCoordinate, pieceAtDestination));
}
}
}
}
return(legalMoves.ToList());
}
/// <summary>
/// calculate all legal moves possible for the bishop
/// </summary>
/// <param name="board"></param>
/// <returns></returns>
public override ICollection <Move> calculateLegalMoves(Board board)
{
IList <Move> legalMoves = new List <Move>();
foreach (int currentCandidateOffset in CANDIDATE_MOVE_COORDINATES)
{
int candidateDestinationCoordinate = this.piecePosition;
while (true)
{
//First or Last column exclusion break
if (IsFirstColumnExclusion(candidateDestinationCoordinate, currentCandidateOffset) ||
IsEighthColumnExclusion(candidateDestinationCoordinate, currentCandidateOffset))
{
break;
}
candidateDestinationCoordinate += currentCandidateOffset;
if (!BoardUtils.IsValidTileCoordinate(candidateDestinationCoordinate))
{
break;
}
else
{
//Set the tile as a valid candidate
Tile candidateDestinationTile = board.getTile(candidateDestinationCoordinate);
//If the candidate Tile is not Occupied
if (!candidateDestinationTile.isTileOccupied())
{
//Add move as legal
legalMoves.Add(new MajorMove(board, this, candidateDestinationCoordinate));
}
else
{
//Tile is occupied
Piece pieceAtDestination = candidateDestinationTile.getPiece();
Alliance pieceAtDestinationAlliance = pieceAtDestination.getPieceAlliance();
//If the piece alliance of the piece at the target tile
//is not the same as the piece alliace of this object...
if (this.pieceAlliance != pieceAtDestinationAlliance)
{
//Add the move into the list of legal moves
legalMoves.Add(new MajorAttackMove(board, this, candidateDestinationCoordinate, pieceAtDestination));
}
break;
}
}
}
}
return(legalMoves.ToList());
}
/// <summary>
/// Calculates the leagal moves for a knight and returns a list of
/// all possible moves
/// </summary>
/// <param name="board"></param>
/// <returns></returns>
public override ICollection <Move> calculateLegalMoves(Board board)
{
int candidateDestinationCoordinate;
IList <Move> legalMoves = new List <Move>();
foreach (int currentCandidateOffset in CANDIDATE_MOVE_COORDINATES)
{
candidateDestinationCoordinate = this.piecePosition + currentCandidateOffset;
//If the tile is a valid tile coordinate for this piece...
if (BoardUtils.IsValidTileCoordinate(candidateDestinationCoordinate))
{
//Check Column exclusions for the knight
if (isFirstColumnExclusion(this.piecePosition, currentCandidateOffset) ||
isSecondColumExclusion(this.piecePosition, currentCandidateOffset) ||
isSeventhColumExclusion(this.piecePosition, currentCandidateOffset) ||
isEighthColumExclusion(this.piecePosition, currentCandidateOffset))
{
continue;
}
//Set the tile as a valid candidate
Tile candidateDestinationTile = board.getTile(candidateDestinationCoordinate);
//If the candidate Tile is not Occupied
if (!candidateDestinationTile.isTileOccupied())
{
//Add move as legal
legalMoves.Add(new MajorMove(board, this, candidateDestinationCoordinate));
}
else
{
//Tile is occupied
Piece pieceAtDestination = candidateDestinationTile.getPiece();
Alliance pieceAlliance = pieceAtDestination.getPieceAlliance();
//If the piece alliance of the piece at the target tile
//is not the same as the piece alliace of this object...
if (this.pieceAlliance != pieceAlliance)
{
//Add the move into the list of legal moves
legalMoves.Add(new MajorAttackMove(board, this, candidateDestinationCoordinate, pieceAtDestination));
}
}
}
}
//Return the calculated legal moves
return(legalMoves.ToList());
}
/// <summary>
/// Pawn legal moves calculations
/// </summary>
/// <param name="board"></param>
/// <returns></returns>
public override ICollection <Move> calculateLegalMoves(Board board)
{
//List of all possible legal moves
IList <Move> legalMoves = new List <Move>();
foreach (int currentCandidateOffset in CANDIDATE_MOVE_COORDINATES)
{
int candidateDestinationCoordinate = this.piecePosition + (this.getPieceAlliance().getDirection() * currentCandidateOffset);
//Check if the candidateCoordinate is a valid board coordinate
if (!BoardUtils.IsValidTileCoordinate(candidateDestinationCoordinate))
{
continue;
}
//Pawns can only move up or down in direction based on alliance
if (currentCandidateOffset == 8 && !board.getTile(candidateDestinationCoordinate).isTileOccupied())
{
//Check for pawn promotion
if (this.pieceAlliance.isPawnPromotionSquare(candidateDestinationCoordinate))
{
//if the pawn is eligible for promotion then promote it
legalMoves.Add(new PawnPromotion(new PawnMove(board, this, candidateDestinationCoordinate)));
}
else
{
//Add this pawn move as a legal move
legalMoves.Add(new PawnMove(board, this, candidateDestinationCoordinate));
}
}
//if the pawns are on starting position then pawns can travel two tiles up or down
else if (currentCandidateOffset == 16 && this.IsFirstMove() &&
((BoardUtils.SECOND_RANK[this.piecePosition] && this.getPieceAlliance().isWhite()) ||
(BoardUtils.SEVENTH_RANK[this.piecePosition] && this.getPieceAlliance().isBlack())))
{
int behindCandidateDestinationCoordinate = this.piecePosition + (this.pieceAlliance.getDirection() * 8);
//Check if the candidate tile is occupied
if (!board.getTile(behindCandidateDestinationCoordinate).isTileOccupied() &&
!board.getTile(candidateDestinationCoordinate).isTileOccupied())
{
//Add this pawn move as a legal move
legalMoves.Add(new PawnJump(board, this, candidateDestinationCoordinate));
}
}
//Attack move on 7 tile move
else if (currentCandidateOffset == 7 &&
!((BoardUtils.EIGHTH_COLUMN[this.piecePosition] && this.getPieceAlliance().isWhite()) ||
(BoardUtils.FIRST_COLUMN[this.piecePosition] && this.getPieceAlliance().isBlack())))
{
if (board.getTile(candidateDestinationCoordinate).isTileOccupied())
{
Piece pieceOnCandidate = board.getTile(candidateDestinationCoordinate).getPiece();
//Opponent piece alliance check
if (this.pieceAlliance != pieceOnCandidate.getPieceAlliance())
{
//Check for pawn promotion
if (this.pieceAlliance.isPawnPromotionSquare(candidateDestinationCoordinate))
{
//if the pawn is eligible for promotion then promote it
legalMoves.Add(new PawnPromotion(new PawnAttackMove(board, this, candidateDestinationCoordinate, pieceOnCandidate)));
}
else
{
//Attack Move
legalMoves.Add(new PawnAttackMove(board, this, candidateDestinationCoordinate, pieceOnCandidate));
}
}
}
//En Passant Condition
else if (board.getEnPassantPawn() != null)
{
if (board.getEnPassantPawn().getPiecePosition() == this.piecePosition + (this.pieceAlliance.getOppositeDirection()))
{
Piece pieceOnCandidate = board.getEnPassantPawn();
if (this.pieceAlliance != pieceOnCandidate.getPieceAlliance())
{
legalMoves.Add(new PawnEnPassantAttackMove(board, this, candidateDestinationCoordinate, pieceOnCandidate));
}
}
}
}
//Attack move on 9 tile move
else if (currentCandidateOffset == 9 &&
!((BoardUtils.FIRST_COLUMN[this.piecePosition] && this.getPieceAlliance().isWhite()) ||
(BoardUtils.EIGHTH_COLUMN[this.piecePosition] && this.getPieceAlliance().isBlack())))
{
if (board.getTile(candidateDestinationCoordinate).isTileOccupied())
{
Piece pieceOnCandidate = board.getTile(candidateDestinationCoordinate).getPiece();
if (this.pieceAlliance != pieceOnCandidate.getPieceAlliance())
{
//Check for pawn promotion
if (this.pieceAlliance.isPawnPromotionSquare(candidateDestinationCoordinate))
{
//if the pawn is eligible for promotion then promote it
legalMoves.Add(new PawnPromotion(new PawnAttackMove(board, this, candidateDestinationCoordinate, pieceOnCandidate)));
}
else
{
//Attack Move
legalMoves.Add(new PawnAttackMove(board, this, candidateDestinationCoordinate, pieceOnCandidate));
}
}
}
//En Passant Condition
else if (board.getEnPassantPawn() != null)
{
if (board.getEnPassantPawn().getPiecePosition() == this.piecePosition - (this.pieceAlliance.getOppositeDirection()))
{
Piece pieceOnCandidate = board.getEnPassantPawn();
if (this.pieceAlliance != pieceOnCandidate.getPieceAlliance())
{
legalMoves.Add(new PawnEnPassantAttackMove(board, this, candidateDestinationCoordinate, pieceOnCandidate));
}
}
}
}
}
return(legalMoves.ToList());
}