from math import inf as infinity from random import choice import platform import time from os import system

HUMAN = -1 COMP = +1 board = [ [0, 0, 0], [0, 0, 0], [0, 0, 0], ]

def evaluate(state):

if wins(state, COMP):
    score = +1
elif wins(state, HUMAN):
    score = -1
else:
    score = 0

return score

def wins(state, player):

win_state = [
    [state[0][0], state[0][1], state[0][2]],
    [state[1][0], state[1][1], state[1][2]],
    [state[2][0], state[2][1], state[2][2]],
    [state[0][0], state[1][0], state[2][0]],
    [state[0][1], state[1][1], state[2][1]],
    [state[0][2], state[1][2], state[2][2]],
    [state[0][0], state[1][1], state[2][2]],
    [state[2][0], state[1][1], state[0][2]],
]
if [player, player, player] in win_state:
    return True
else:
    return False

def game_over(state):

return wins(state, HUMAN) or wins(state, COMP)

def empty_cells(state):

cells = []

for x, row in enumerate(state):
    for y, cell in enumerate(row):
        if cell == 0:
            cells.append([x, y])

return cells

def valid_move(x, y):

if [x, y] in empty_cells(board):
    return True
else:
    return False

def set_move(x, y, player):

if valid_move(x, y):
    board[x][y] = player
    return True
else:
    return False

def minimax(state, depth, player):

if player == COMP:
    best = [-1, -1, -infinity]
else:
    best = [-1, -1, +infinity]

if depth == 0 or game_over(state):
    score = evaluate(state)
    return [-1, -1, score]

for cell in empty_cells(state):
    x, y = cell[0], cell[1]
    state[x][y] = player
    score = minimax(state, depth - 1, -player)
    state[x][y] = 0
    score[0], score[1] = x, y

    if player == COMP:
        if score[2] > best[2]:
            best = score  # max value
    else:
        if score[2] < best[2]:
            best = score  # min value

return best

def clean():

os_name = platform.system().lower()
if 'windows' in os_name:
    system('cls')
else:
    system('clear')

def render(state, c_choice, h_choice):

chars = {
    -1: h_choice,
    +1: c_choice,
    0: ' '
}
str_line = '---------------'

print('\n' + str_line)
for row in state:
    for cell in row:
        symbol = chars[cell]
        print(f'| {symbol} |', end='')
    print('\n' + str_line)

def ai_turn(c_choice, h_choice):

depth = len(empty_cells(board))
if depth == 0 or game_over(board):
    return

clean()
print(f'Computer turn [{c_choice}]')
render(board, c_choice, h_choice)

if depth == 9:
    x = choice([0, 1, 2])
    y = choice([0, 1, 2])
else:
    move = minimax(board, depth, COMP)
    x, y = move[0], move[1]

set_move(x, y, COMP)
time.sleep(1)

def human_turn(c_choice, h_choice):

depth = len(empty_cells(board))
if depth == 0 or game_over(board):
    return

# Dictionary of valid moves
move = -1
moves = {
    1: [0, 0], 2: [0, 1], 3: [0, 2],
    4: [1, 0], 5: [1, 1], 6: [1, 2],
    7: [2, 0], 8: [2, 1], 9: [2, 2],
}

clean()
print(f'Human turn [{h_choice}]')
render(board, c_choice, h_choice)

while move < 1 or move > 9:
    try:
        move = int(input('Use numpad (1..9): '))
        coord = moves[move]
        can_move = set_move(coord[0], coord[1], HUMAN)

        if not can_move:
            print('Bad move')
            move = -1
    except (EOFError, KeyboardInterrupt):
        print('Bye')
        exit()
    except (KeyError, ValueError):
        print('Bad choice')

def main(): """ Main function that calls all functions """ clean() h_choice = '' # X or O c_choice = '' # X or O first = '' # if human is the first

# Human chooses X or O to play
while h_choice != 'O' and h_choice != 'X':
    try:
        print('')
        h_choice = input('Choose X or O\nChosen: ').upper()
    except (EOFError, KeyboardInterrupt):
        print('Bye')
        exit()
    except (KeyError, ValueError):
        print('Bad choice')

# Setting computer's choice
if h_choice == 'X':
    c_choice = 'O'
else:
    c_choice = 'X'

# Human may starts first
clean()
while first != 'Y' and first != 'N':
    try:
        first = input('First to start?[y/n]: ').upper()
    except (EOFError, KeyboardInterrupt):
        print('See you soon')
        exit()
    except (KeyError, ValueError):
        print('Open your eyes!!')

# Main loop of this game
while len(empty_cells(board)) > 0 and not game_over(board):
    if first == 'N':
        ai_turn(c_choice, h_choice)
        first = ''

    human_turn(c_choice, h_choice)
    ai_turn(c_choice, h_choice)

# Game over message
if wins(board, HUMAN):
    clean()
    print(f'Human turn [{h_choice}]')
    render(board, c_choice, h_choice)
    print('YOU WIN! Congrats!!!')
elif wins(board, COMP):
    clean()
    print(f'Computer turn [{c_choice}]')
    render(board, c_choice, h_choice)
    print('YOU LOSE!')
else:
    clean()
    render(board, c_choice, h_choice)
    print('DRAW!!!')

exit()

if name == 'main': main()