CJ_Check | Python Fiddle

ROW = 0
COLUMN = 1
COORDINATE = 0
REPEAT = 1
KING = ' K '
QUEEN = ' Q '
BISHOP = ' B '
KNIGHT = ' N '
ROOK = ' R '
PAWN = ' P '
NOPIECE = ' 0 '
PATH = ' * '
SPACE = ' '
BLACK = 'BLACK'
WHITE = 'WHITE'
NORTH = [-1, 0]
SOUTH = [1, 0]
EAST = [0, 1]
WEST = [0, -1]
NORTHEAST = [-1, 1]
SOUTHEAST = [1, 1]
SOUTHWEST = [1, -1]
NORTHWEST = [-1, -1]
KNIGHT1 = [-2, 1]
KNIGHT2 = [-1, 2]
KNIGHT3 = [1, 2]
KNIGHT4 = [2, 1]
KNIGHT5 = [2, -1]
KNIGHT6 = [1, -2]
KNIGHT7 = [-1, -2]
KNIGHT8 = [-2, -1]
UNLIM = True
ONESTEP = False
BOARDSIZE = 8
OCCUPIED = False
UNOCCUPIED = True
OCCUPIEDPOSITION = 0
PIECEPOSITION = 1
blackCheck = False
whiteCheck = False

class ChessPiece:
	'''
	piece is they type of piece per PIECES list representing the types
		of chess pieces
	ROM is the range of motion which is a list containing elements which
		list the possible single-move displacements along with a true or 
		false for whether the piece can move unlimited in the direction 
	color is the color of the piece per COLORS list representing the two
		sides of a chess board
	position is the coordinate two-element list of the piece position on
		the board
	'''
	#Not sure how to make better use of this
	PIECES = [KING,QUEEN,BISHOP,KNIGHT,ROOK,PAWN]
	COLORS = [BLACK,WHITE]
	UNLIMITED = [UNLIM,ONESTEP]
		
	def __init__(self, Piece, Color, Position):
		self.piece = Piece
		self.color = Color
		self.position = Position
		if Piece == KING:
			self.ROM = [[NORTH,ONESTEP],[NORTHEAST,ONESTEP],[EAST,ONESTEP],[SOUTHEAST,ONESTEP],[SOUTH,ONESTEP],[SOUTHWEST,ONESTEP],[WEST,ONESTEP],[NORTHWEST,ONESTEP]]
		elif Piece == QUEEN:
			self.ROM = [[NORTH,UNLIM],[NORTHEAST,UNLIM],[EAST,UNLIM],[SOUTHEAST,UNLIM],[SOUTH,UNLIM],[SOUTHWEST,UNLIM],[WEST,UNLIM],[NORTHWEST,UNLIM]]
		elif Piece == BISHOP:
			self.ROM = [[NORTHEAST,UNLIM],[SOUTHEAST,UNLIM],[SOUTHWEST,UNLIM],[NORTHWEST,UNLIM]]
		elif Piece == KNIGHT:
			self.ROM = [[KNIGHT1,ONESTEP],[KNIGHT2,ONESTEP],[KNIGHT3,ONESTEP],[KNIGHT4,ONESTEP],[KNIGHT5,ONESTEP],[KNIGHT6,ONESTEP],[KNIGHT7,ONESTEP],[KNIGHT8,ONESTEP]]
		elif Piece == ROOK:
			self.ROM = [[NORTH,UNLIM],[SOUTH,UNLIM],[EAST,UNLIM],[WEST,UNLIM]]
		elif Piece == PAWN:
			if Color == WHITE:
				self.ROM = [[SOUTHEAST,ONESTEP],[SOUTHWEST,ONESTEP]]
			else:
				self.ROM = [[NORTHEAST,ONESTEP],[NORTHWEST,ONESTEP]]
		else:
			return None

def checkInBounds(pTC):#pTC = positionToCheck
	if pTC[ROW] <= BOARDSIZE and pTC[ROW] > 0 and pTC[COLUMN] <= BOARDSIZE and pTC[COLUMN] > 0:
		return True
	else:
		return False

def movePosition(cP,dP):#cP = currentPosition; dP = deltaPosition
	return [cP[ROW] + dP[ROW],cP[COLUMN] + dP[COLUMN]]

def readBoard():
	board = []
	print "Welcome to the Check program."
	print "You will enter characters to simulate the layout on a chess board."
	print "Enter 8 characters for each row without spaces, followed by <Enter>."
	print "Enter all 8 rows of the chess board."
	print "White plays from the top of the board and black from the bottom."
	print "Enter lowercase letters for the white pieces."
	print "Enter uppercase letters for the black pieces."
	print "Enter '0' for blank squares."
	print "Enter 'K' or 'k' for the king."
	print "Enter 'Q' or 'q' for the king."
	print "Enter 'B' or 'b' for the bishop."
	print "Enter 'N' or 'n' for the knight."
	print "Enter 'R' or 'r' for the rook."
	print "Enter 'P' or 'p' for the pawn."
	rowNum = 1
	while rowNum <= BOARDSIZE:
		row = []
		passedValidation = True
		line = raw_input()
		if len(line) > 8 or len(line) < 8:
			print "Line not the correct length. Re-enter it."
		else:
			colNum = 1
			for c in line:
				newPiece = SPACE + c.upper() + SPACE
				if c == c.lower():
					pieceColor = WHITE
				else:
					pieceColor = BLACK
				if newPiece == KING:
					row.append(ChessPiece(KING, pieceColor, [rowNum, colNum]))
					colNum += 1
				elif newPiece == QUEEN:
					row.append(ChessPiece(QUEEN, pieceColor, [rowNum, colNum]))
					colNum += 1
				elif newPiece == BISHOP:
					row.append(ChessPiece(BISHOP, pieceColor, [rowNum, colNum]))
					colNum += 1
				elif newPiece == KNIGHT:
					row.append(ChessPiece(KNIGHT, pieceColor, [rowNum, colNum]))
					colNum += 1
				elif newPiece == ROOK:
					row.append(ChessPiece(ROOK, pieceColor, [rowNum, colNum]))
					colNum += 1
				elif newPiece == PAWN:
					row.append(ChessPiece(PAWN, pieceColor, [rowNum, colNum]))
					colNum += 1
				elif newPiece == NOPIECE:
					colNum += 1
				else:
					print "Incorrect character entered. Please re-enter line."
					passedValidation = False
					break
			if passedValidation:
				rowNum += 1
				for i in range(len(row)):
					board.append(row[i])
	return board

def isUnOccupied(positionTC, piecesTC): #positionTC = positionToCheck; piecesTC = piecesToCheck
	status = [UNOCCUPIED]
	for p in piecesTC:
		if p.position == positionTC:
			status = [OCCUPIED, p]
	return status

def checkForCheck(piecesList):
	global blackCheck
	global whiteCheck
	for p1 in piecesList:
		piecePosition = p1.position
		for delta in p1.ROM:
			checkPosition = movePosition(piecePosition, delta[COORDINATE])
			if delta[REPEAT]:
				while checkInBounds(checkPosition) and isUnOccupied(checkPosition, piecesList)[OCCUPIEDPOSITION]:
					checkPosition = movePosition(checkPosition, delta[COORDINATE])
				if not isUnOccupied(checkPosition, piecesList)[OCCUPIEDPOSITION]:
					if isUnOccupied(checkPosition, piecesList)[PIECEPOSITION].piece == KING:
						if isUnOccupied(checkPosition, piecesList)[PIECEPOSITION].color == WHITE and p1.color == BLACK:
							whiteCheck = True
						elif isUnOccupied(checkPosition, piecesList)[PIECEPOSITION].color == BLACK and p1.color == WHITE:
							blackCheck = True
			else:
				if checkInBounds(checkPosition):
					if not isUnOccupied(checkPosition, piecesList)[OCCUPIEDPOSITION]:
						if isUnOccupied(checkPosition, piecesList)[PIECEPOSITION].piece == KING:
							if isUnOccupied(checkPosition, piecesList)[PIECEPOSITION].color == WHITE and p1.color == BLACK:
								whiteCheck = True
								#print "White King is in check"
							elif isUnOccupied(checkPosition, piecesList)[PIECEPOSITION].color == BLACK and p1.color == WHITE:
								blackCheck = True
								#print "Black King is in check"

pieces = readBoard()
#pieces = [ChessPiece(ROOK, WHITE, [3,3]), ChessPiece(KING, BLACK, [5,7]),ChessPiece(QUEEN, WHITE, [5,5])]
checkForCheck(pieces)
if blackCheck and whiteCheck:
	print "Both kings are in check."
elif blackCheck:
	print "The black king is in check."
elif whiteCheck:
	print "The white king is in check."
else:
	print "No kings are in check."

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