tic_tac_toe_ai.py

import pygame
import sys

# Initialize Pygame
pygame.init()

# Constants
WIDTH, HEIGHT = 300, 300
LINE_WIDTH = 5
BOARD_ROWS = 3
BOARD_COLS = 3
SQUARE_SIZE = WIDTH // BOARD_COLS
CIRCLE_RADIUS = SQUARE_SIZE // 3
CIRCLE_WIDTH = 15
CROSS_WIDTH = 25
SPACE = SQUARE_SIZE // 4

# Colors
BG_COLOR = (28, 170, 156)
LINE_COLOR = (23, 145, 135)
CIRCLE_COLOR = (239, 231, 200)
CROSS_COLOR = (84, 84, 84)

# Initialize screen
screen = pygame.display.set_mode((WIDTH, HEIGHT))
pygame.display.set_caption('Tic-Tac-Toe')
screen.fill(BG_COLOR)

def draw_lines():
    # Horizontal lines
    pygame.draw.line(screen, LINE_COLOR, (0, SQUARE_SIZE), (WIDTH, SQUARE_SIZE), LINE_WIDTH)
    pygame.draw.line(screen, LINE_COLOR, (0, 2 * SQUARE_SIZE), (WIDTH, 2 * SQUARE_SIZE), LINE_WIDTH)
    # Vertical lines
    pygame.draw.line(screen, LINE_COLOR, (SQUARE_SIZE, 0), (SQUARE_SIZE, HEIGHT), LINE_WIDTH)
    pygame.draw.line(screen, LINE_COLOR, (2 * SQUARE_SIZE, 0), (2 * SQUARE_SIZE, HEIGHT), LINE_WIDTH)

def draw_figures(board):
    for row in range(BOARD_ROWS):
        for col in range(BOARD_COLS):
            if board[row][col] == 'O':
                pygame.draw.circle(screen, CIRCLE_COLOR, (int(col * SQUARE_SIZE + SQUARE_SIZE // 2), int(row * SQUARE_SIZE + SQUARE_SIZE // 2)), CIRCLE_RADIUS, CIRCLE_WIDTH)
            elif board[row][col] == 'X':
                pygame.draw.line(screen, CROSS_COLOR, (col * SQUARE_SIZE + SPACE, row * SQUARE_SIZE + SQUARE_SIZE - SPACE), (col * SQUARE_SIZE + SQUARE_SIZE - SPACE, row * SQUARE_SIZE + SPACE), CROSS_WIDTH)
                pygame.draw.line(screen, CROSS_COLOR, (col * SQUARE_SIZE + SPACE, row * SQUARE_SIZE + SPACE), (col * SQUARE_SIZE + SQUARE_SIZE - SPACE, row * SQUARE_SIZE + SQUARE_SIZE - SPACE), CROSS_WIDTH)

draw_lines()

def check_winner(board, player):
    # Check rows
    for row in range(BOARD_ROWS):
        if board[row][0] == board[row][1] == board[row][2] == player:
            return True
    # Check columns
    for col in range(BOARD_COLS):
        if board[0][col] == board[1][col] == board[2][col] == player:
            return True
    # Check diagonals
    if board[0][0] == board[1][1] == board[2][2] == player:
        return True
    if board[2][0] == board[1][1] == board[0][2] == player:
        return True
    return False

def restart():
    screen.fill(BG_COLOR)
    draw_lines()
    return [[" " for _ in range(BOARD_COLS)] for _ in range(BOARD_ROWS)]

board = restart()
current_player = 'X'
game_over = False

# This code is use to play for 2 players 

# while True:
#     for event in pygame.event.get():
#         if event.type == pygame.QUIT:
#             pygame.quit()
#             sys.exit()
#         if event.type == pygame.MOUSEBUTTONDOWN and not game_over:
#             mouseX = event.pos[0]  # X coordinate
#             mouseY = event.pos[1]  # Y coordinate

#             clicked_row = int(mouseY // SQUARE_SIZE)
#             clicked_col = int(mouseX // SQUARE_SIZE)

#             if board[clicked_row][clicked_col] == " ":
#                 board[clicked_row][clicked_col] = current_player
#                 draw_figures(board)
#                 if check_winner(board, current_player):
#                     game_over = True
#                 current_player = 'O' if current_player == 'X' else 'X'

#         if event.type == pygame.KEYDOWN:
#             if event.key == pygame.K_r:
#                 board = restart()
#                 game_over = False
#                 current_player = 'X'

#     pygame.display.update()


# for this extra  function is used to play with ai
def check_draw(board):
    for row in range(BOARD_ROWS):
        for col in range(BOARD_COLS):
            if board[row][col] == " ":
                return False
    return True

def minimax(board, depth, is_maximizing):
    if check_winner(board, 'O'):
        return 1
    if check_winner(board, 'X'):
        return -1
    if check_draw(board):
        return 0

    if is_maximizing:
        best_score = -float('inf')
        for row in range(BOARD_ROWS):
            for col in range(BOARD_COLS):
                if board[row][col] == " ":
                    board[row][col] = 'O'
                    score = minimax(board, depth + 1, False)
                    board[row][col] = " "
                    best_score = max(score, best_score)
        return best_score
    else:
        best_score = float('inf')
        for row in range(BOARD_ROWS):
            for col in range(BOARD_COLS):
                if board[row][col] == " ":
                    board[row][col] = 'X'
                    score = minimax(board, depth + 1, True)
                    board[row][col] = " "
                    best_score = min(score, best_score)
        return best_score

def best_move(board):
    best_score = -float('inf')
    move = None
    for row in range(BOARD_ROWS):
        for col in range(BOARD_COLS):
            if board[row][col] == " ":
                board[row][col] = 'O'
                score = minimax(board, 0, False)
                board[row][col] = " "
                if score > best_score:
                    best_score = score
                    move = (row, col)
    return move

# Modify the game loop to include AI moves
while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            sys.exit()
        if event.type == pygame.MOUSEBUTTONDOWN and not game_over:
            mouseX = event.pos[0]  # X coordinate
            mouseY = event.pos[1]  # Y coordinate

            clicked_row = int(mouseY // SQUARE_SIZE)
            clicked_col = int(mouseX // SQUARE_SIZE)

            if board[clicked_row][clicked_col] == " ":
                board[clicked_row][clicked_col] = current_player
                draw_figures(board)
                if check_winner(board, current_player):
                    game_over = True
                current_player = 'O' if current_player == 'X' else 'X'
                
                # AI move
                if not game_over and current_player == 'O':
                    ai_move = best_move(board)
                    if ai_move:
                        board[ai_move[0]][ai_move[1]] = 'O'
                        draw_figures(board)
                        if check_winner(board, 'O'):
                            game_over = True
                        current_player = 'X'

        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_r:
                board = restart()
                game_over = False
                current_player = 'X'

    pygame.display.update()