def is_valid_board(board):
"""
Check if the board is valid. The board is considered valid if the sum of
all values in the board, sum, is such that -1 <= sum <= 1, the only values in
the board are config.COMPUTER, config.HUMAN, and config.NO_PLAYER, and the length
of the board is 9.
@param board: the board state you want to check.
@return: True if the board is considered valid, False if not.
"""
valid = len(board) == 9
valid &= -1 <= sum(board) <= 1
valid &= reduce(lambda x, y: x and y, [utils.is_valid_player(p) for p in board])
return valid
def make_move(board, index, p):
"""
Checks to see that the move is valid.
@param board: the board state you want to check.
@param index: the index of the board array where you want to make
the move for p.
@param p: the game_player making the move. p=1 or p=-1
@return: Returns a board representing the new board state if index is a
valid move. If p is not a valid value for a game_player, it will raise an
exception. If the resulting board is invalid (say you have 3 X moves and 1 O
move) it will also throw an exception.
"""
if not utils.is_valid_player(p) or p == config.NO_PLAYER:
raise Exception("Input p must = {0} or {1}. p = {3}".format(config.HUMAN, config.COMPUTER, p))
result = copy.deepcopy(board)
result[index] = p
if not is_valid_board(result):
raise Exception("Move for {0} at {1} is invalid.".format(p, index))
return result
