#!/usr/bin/env python
""" tic-tac-toe programming design
	as a course exercise on Oct 20
	
	The user would see something like this:
	
	 X | O |               a | b | c
	---+---+---  	      ---+---+---
	   |   |               d | e | f
	---+---+--- 	      ---+---+---
	   |   |               g | h | i
	   
	Where would you like to put an X ? 

    The user is first asked whether they
    want to play X or O.
    X moves first.
    Moves are input as the letters 
    The program recognizes when someone has won
    and says so.
    The computer plays legal moves.
	
"""

board     = [ [' ']*3, [' ']*3, [' ']*3 ]
help_text = [ ' a | b | c',
			  ' d | e | f',
			  ' g | h | i',
			]

who = ['X', 'O', 0]  # [ user, computer, next_to_move]

def print_board():
	bar = '---+---+---'
	for row in range(0,len(board)):
		print ' ' + ' | '.join(board[row]),
		print ' '*6 + help_text[row]
		if row == len(board)-1:
			break
		print bar + ' '*6 + bar

def change_board(move):
	""" apply this move to the global board"""
	# not written yet

def get_move():
	""" return a move for either the user or computer"""
	# not yet

def is_winner():
	""" return true if someone has won.
		As a side effect, print a message saying so."""
	print "We have a winner!"
	return True

def pick_sides():
	""" Decide who plays X and who plays O """

def play_game():
	print " tic tac toe "
	while True:   # outer loop over multiple game
		pick_sides()
		while True:
			print_board()
			change_board(get_move())
			if is_winner():
				break
		raw_input("Another game? (cntl-C to exit)")
		print "Good, here we go."
		print