'''An object-oriented game of Tic Tac Toe.'''

EMPTY = " " # marker for an empty square
SIZE = 3 # size of the game board
DASHES = 7 * '-' # used in printing

class TicTacToe:
    '''A text-based game of Tic-Tac-Toe'''


    def __init__(self):
        '''Initialize the game board.'''
        self.board = []
        for row_num in range(SIZE):
            board_row = []
            for col_num in range(SIZE):
                board_row.append(EMPTY)
            self.board.append(board_row)
            
        self.winner = None # who has won the game
        self.empty_squares = SIZE * SIZE # number of empty squares left

    
    def __str__(self):
        '''Draw the game board.'''
        board_str = DASHES + "\n"
        for row in self.board:
            board_str += "|"
            for marker in row:
                board_str += marker + "|"
            board_str += "\n" + DASHES + "\n"
        return board_str


    def read_move(self):
        '''Read in a move as x,y'''
        valid_move = False
        while not valid_move:
            input_str = input('Enter a move r, c: ')
            try:
                (play_x, play_y) = input_str.split(',')
                play_x = int(play_x) - 1
                play_y = int(play_y) - 1
                if play_x >= 0 and play_y >= 0 and self.board[play_x][play_y] == EMPTY:
                    valid_move = True
                else:
                    print("Invalid move, try again")
            except:
                print("Invalid move, try again")
        return (play_x, play_y)        
        
        
    def make_play(self, player, row_num, col_num):
        '''Set the given square at (row, col) to the given player's marker.'''
        if self.board[row_num][col_num] != EMPTY:
            self.empty_squares -= 1
        self.board[row_num][col_num] = player.marker

        
    
    def game_over(self, last_player, row_played, col_played):
        '''Given the last player to play and where they played, returns whether
        the game is over and sets self.winner if the player has won.'''
        
        if last_player == None: # ignore on the first check
            return False        
        
        if self.empty_squares == 0: # all squares played
            return True
        
        marker = last_player.marker
        
        # check the row through row_played
        win = True
        for col in range(SIZE):
            if self.board[row_played][col] != marker:
                win = False
                break
        if win:
            self.winner = last_player
            return True
        
        # check the col through col_played
        win = True
        for row in range(SIZE):
            if self.board[row][col_played] != marker:
                win = False
                break
        if win:
            self.winner = last_player
            return True
        

        # right diag
        win = True
        for i in range(SIZE):
            if self.board[i][i] != marker:
                win = False
                break
        if win:
            self.winner = last_player
            return True
        
        # left diag
        win = True
        for i in range(SIZE):
            if self.board[i][SIZE - 1 - i] != marker:
                win = False
                break
        if win:
            self.winner = last_player
            return True
            
        # otherwise, not a win
        return False 
    


class Player:
    '''A player of the game represented as a name and a marker.'''

    
    def __init__(self, name, marker):
        self.name = name
        self.marker = marker
    
    
    def __str__(self):
        return self.name + " (" + self.marker + ")"
     


def main():
    '''Run a game of tic tac toe.'''
    
    ttt = TicTacToe()
    player1 = Player('Alice', 'A')
    player2 = Player('Bob', 'B')
    
    cur_player = None
    play_x = None
    play_y = None
    
    while not ttt.game_over(cur_player, play_x, play_y):
        print(ttt)
        if cur_player == player1:
            cur_player = player2
        else:
            cur_player = player1
        print(str(cur_player) + "'s move")
        (play_x, play_y) = ttt.read_move()
        ttt.make_play(cur_player, play_x, play_y)
               
    print(ttt)
    
    if ttt.winner == None:
        print("No winner!")
    else:
        print(ttt.winner, "wins!")
    
main()