def in_board(self, coordinate: Coordinate) -> bool:
"""
returns whether a coordinate is within the bounds of the board
arguments:
coordinate -- coordinate to check
"""
return (coordinate.get_rank() >= 0 and coordinate.get_file() >= 0
and coordinate.get_rank() < self.HEIGHT
and coordinate.get_file() < self.WIDTH)
def get_diagonal_moves(self, piece: Piece,
board: List[List[Piece]]) -> List[Move]:
"""
returns a list of all diagonal moves
arguments:
piece -- piece to generate moves
board -- board to validate moves
"""
if piece.piece_type != Type.BISHOP and piece.piece_type != Type.QUEEN:
return []
directions: List[Tuple[int, int]] = [(1, 1), (-1, 1), (-1, -1),
(1, -1)]
moves: List[Move] = []
for direction in directions:
destination: Coordinate = Coordinate(
piece.coordinate.get_rank() + direction[0],
piece.coordinate.get_file() + direction[1],
)
while self.in_board(destination):
moves.append(
Move(piece.coordinate, destination,
self.piece_at(destination, board)))
if self.piece_at(destination, board):
break
destination = Coordinate(
destination.get_rank() + direction[0],
destination.get_file() + direction[1],
)
return moves
def piece_at(self, coordinate: Coordinate,
board: List[List[Piece]]) -> Union[Piece, None]:
"""
returns a reference to the piece at a specified coordinate, if no piece is present returns None
arguments:
coordinate -- coordinate to check
board -- board to check for piece in
"""
if not self.in_board(coordinate):
return None
else:
return board[coordinate.get_rank()][coordinate.get_file()]
def get_pawn_moves(self, piece: Piece,
board: List[List[Piece]]) -> List[Move]:
"""
returns a list of all pawn moves
arguments:
piece -- piece to generate moves
board -- board to validate moves
"""
if piece.piece_type != Type.PAWN:
return []
direction: int = 1 if piece.color == Color.WHITE else -1
moves: List[Move] = []
# Add one square move
destination: Coordinate = Coordinate(
piece.coordinate.get_rank() + 1 * direction,
piece.coordinate.get_file())
if self.in_board(destination) and not self.piece_at(
destination, board):
if (piece.color == Color.WHITE and destination.get_rank()
== self.HEIGHT - 1) or (piece.color == Color.BLACK
and destination.get_rank() == 0):
moves.append(
Move(piece.coordinate, destination, False,
MoveType.N_PROMO))
moves.append(
Move(piece.coordinate, destination, False,
MoveType.B_PROMO))
moves.append(
Move(piece.coordinate, destination, False,
MoveType.R_PROMO))
moves.append(
Move(piece.coordinate, destination, False,
MoveType.Q_PROMO))
else:
moves.append(Move(piece.coordinate, destination))
# Add two square move
destination = Coordinate(
piece.coordinate.get_rank() + 2 * direction,
piece.coordinate.get_file())
if (not piece.moved and self.in_board(destination)
and not self.piece_at(destination, board)
and ((piece.coordinate.get_rank() == 1
and piece.color == Color.WHITE) or
(piece.coordinate.get_rank() == self.HEIGHT - 2
and piece.color == Color.BLACK))):
moves.append(
Move(piece.coordinate, destination, False,
MoveType.DOUBLE))
# Add capturing moves (default and en passant)
for offset in [-1, 1]:
destination = Coordinate(
piece.coordinate.get_rank() + 1 * direction,
piece.coordinate.get_file() + offset,
)
# Add en passant moves
if (self.in_board(destination) and self.en_passant_target
and destination == self.en_passant_target):
moves.append(
Move(piece.coordinate, destination, False,
MoveType.EN_PASSANT))
# Add default capturing moves
elif self.in_board(destination) and self.piece_at(
destination, board):
if (piece.color == Color.WHITE and destination.get_rank()
== self.HEIGHT - 1) or (piece.color == Color.BLACK and
destination.get_rank() == 0):
moves.append(
Move(piece.coordinate, destination, True,
MoveType.N_PROMO))
moves.append(
Move(piece.coordinate, destination, True,
MoveType.B_PROMO))
moves.append(
Move(piece.coordinate, destination, True,
MoveType.R_PROMO))
moves.append(
Move(piece.coordinate, destination, True,
MoveType.Q_PROMO))
else:
moves.append(Move(piece.coordinate, destination, True))
return moves
