tictactoe.py

import numpy as np

class Board:
    # looks like this:
    #   1 2 3
    # a x x o
    # b x o -
    # c - - x

    def init(self):
        self.contents = np.array(["-" for i in range(9)]).reshape((3,3))
        self.won = False

    def mark(self,location,symbol):
        letter_translator = {'a':0,'b':1,'c':2}
        row = letter_translator[location[0]]
        col = int(location[1])-1
        self.contents[row,col] = symbol

    def check_wins(self):
        def check_if_all_equal(triplet):
            return (
                triplet[0] != "-" and triplet[1] != "-" and triplet[2] != "-" and
                triplet[0] == triplet[1] and triplet[1] == triplet[2]
            )

        triplets = []
        # horizontal
        triplets.append(self.contents[0,:])
        triplets.append(self.contents[1,:])
        triplets.append(self.contents[2,:])
        # vertical
        triplets.append(self.contents[:,0])
        triplets.append(self.contents[:,1])
        triplets.append(self.contents[:,2])
        # diagonal
        triplets.append(self.contents.diagonal())
        triplets.append(self.contents.transpose().diagonal())
        
        checks = []
        for triplet in triplets:
            checks.append(check_if_all_equal(triplet))
        if sum(checks) > 0:
            self.won = True

    def show(self):
        print(
            "  1 2 3"
            + "\na " + " ".join(list(self.contents[0,:]))
            + "\nb " + " ".join(list(self.contents[1,:]))
            + "\nc " + " ".join(list(self.contents[2,:]))
        )

# main
board = Board()
board.init()
game_over = False
symbol = 'X' # O goes first, will be switched in first step of loop
switch = {'O':'X','X':'O'}

while not game_over:
    while not board.won:
        symbol = switch[symbol]
        board.show()
        location = input("Input: ")
        board.mark(location,symbol)
        board.check_wins()
        
    print(f"Player {symbol} won!!")

    val = input("Replay? (y/[n])")
    if val == "y":
        board.init()
        game_over = False
    else:
        game_over = True


# # AI
# Moves that will block an opponents 2 pattern
# Moves that will form a winning pattern - sorted by how many patterns it can form
# Moves that disorient the opponent - farthest from your existing tiles