tictactoe.py

import random

# The indices in state represent this tic tac toe board
#
# index 0 | index 1 | index 2
# ---------------------------
# index 3 | index 4 | index 5
# ---------------------------
# index 6 | index 7 | index 8

class TTT:
    def __init__(self):
        self.state = ['-' for i in range(9)]
        self.nothing = '-'
        self.computer = 'x'
        self.turn = self.computer
        self.player = 'o'
        self.winner = None

    def make_move(self, coord, player):
        self.state[coord] = player
        if self.turn == self.computer: 
            self.turn = self.player 
        else:
            self.turn = self.computer

    def possible_moves(self):
        return [i for (i,val) in enumerate(self.state) if val == self.nothing]

    def computer_move(self):
        coord = random.choice(self.possible_moves())
        self.make_move(coord, self.computer)
        self.set_winner()

    def random_player_move(self):
        coord = random.choice(self.possible_moves())
        self.make_move(coord, self.player)
        self.set_winner()

    def is_live(self):
        return self.winner == None and len(self.possible_moves()) > 0

    def get_game_result(self):
        if self.winner == None:
            return 'draw'
        else:
            return self.winner
            
    def set_winner(self):
        if (self.is_winner(self.player)):
            self.winner = self.player
        if (self.is_winner(self.computer)):
            self.winner = self.computer

    def is_winner(self, player):
        state = self.state
        if (
            # top horizontal 3
            (state[0] == player and state[1] == player and state[2] == player) or
            # mid horizontal 3
            (state[3] == player and state[4] == player and state[5] == player) or
            # bot horizontal 3
            (state[6] == player and state[7] == player and state[8] == player) or
            # left vertial 3
            (state[0] == player and state[3] == player and state[6] == player) or
            # mid vertial 3
            (state[1] == player and state[4] == player and state[7] == player) or
            # right vertial 3
            (state[2] == player and state[5] == player and state[8] == player) or
            # diagonal from top left 
            (state[0] == player and state[4] == player and state[8] == player) or
            # diagonal from top right 
            (state[2] == player and state[4] == player and state[6] == player)
        ):
            return True
        else:
            return False

    def print_board(self):
        print(f" {self.state[0]} | {self.state[1]} | {self.state[2]} \n" \
              f"-----------\n" \
              f" {self.state[3]} | {self.state[4]} | {self.state[5]} \n"\
              f"-----------\n" \
              f" {self.state[6]} | {self.state[7]} | {self.state[8]} \n")