Terminal Tic Tac Toe

tictactoe.py

print("================ Tic Tac Toe ================")

def printBoard(gameState):
	"""Print out the current state of the board"""
	boardString = '''
	 0    |1    |2    
	   {0}  |  {1}  |  {2}  
	 _____|_____|_____
	 3    |4    |5    
	   {3}  |  {4}  |  {5}
	 _____|_____|_____
	 6    |7    |8    
	   {6}  |  {7}  |  {8}
	      |     |    
	'''
	print(boardString.format(*gameState))

def checkWinner(gameState):
	"""Return "X" or "O" if there is a winner, and None otherwise"""
	lines = [
	    [0, 1, 2],
	    [3, 4, 5],
	    [6, 7, 8],
	    [0, 3, 6],
	    [1, 4, 7],
	    [2, 5, 8],
	    [0, 4, 8],
	    [2, 4, 6],
  	]
	for line in lines:
		[a, b, c] = line
		if gameState[a] != " " and gameState[a] == gameState[b] and gameState[a] == gameState[c]:
			return gameState[a]

hasComputerPlayer = False
isXsTurn = True

def turn(gameState):
	"""Handle a single turn of Tic Tac Toe"""
	global isXsTurn

	printBoard(gameState)
	if isXsTurn:
		print("X's Turn")
		num = int(input("Where will you place your X? (0-8) "))
	else:
		print("O's Turn")
		if hasComputerPlayer:
			num = computerTurn()
		else:
			num = int(input("Where will you place your O? (0-8) "))
	if num in range(0, 9):
		if gameState[num] == " ":
			gameState[num] = ("X" if isXsTurn else "O")
			isXsTurn = not isXsTurn
		else:
			print("That square is occupied. Try again.")
	else:
		print("Be sure to pick a number in the range 0-8. Try again.")

def computerTurn():
	# TODO Return a number from 0-8 where the computer will place an O
	return -1

def playGame():
	"""Play a game of Tic Tac Toe"""
	gameState = [" "] * 9
	isXsTurn = True

	winner = checkWinner(gameState)
	while winner == None:
		turn(gameState)
		winner = checkWinner(gameState)

	printBoard(gameState)
	print("Winner: %s" % checkWinner(gameState))

playGame()