Game of Tic Tac Toe

tictactoe_turtle_v4.py

# Version 4: 
#     draws the board
#     allows a user to click on the cells
#     only allows a cell to be used once
#     detects when a user wins
#     draws the winning line 
#     detects ties
from turtle import Turtle

def vertical_line(x, y):
    t = Turtle()
    t.speed('fastest')
    t.hideturtle()
    t.up()
    t.goto(x, y)
    t.color('blue')
    t.down()
    t.right(90)
    t.forward(300)
    
def horizontal_line(x, y):
    t = Turtle()
    t.speed('fastest')
    t.hideturtle()
    t.up()
    t.goto(x, y)
    t.color('blue')
    t.down()
    t.forward(300)

def winning_line(x, y, type):
    t = Turtle()
    t.speed('slow')
    t.width(10)
    t.hideturtle()
    t.up()
    t.goto(x, y)
    t.color('green')
    t.down()

    if type == "vertical":
        t.right(90)
        t.forward(225)
    elif type == "horizontal":
        t.forward(225)
    elif type == "diagonal-a-i":
        t.right(45)
        t.forward(300)
    elif type == "diagonal-c-g":
        t.right(135)
        t.forward(300)
    else:
        print(f"Type {type} is not valid")
        
def draw_x(x, y):
    t = Turtle()
    t.speed('fastest')
    t.hideturtle()
    t.color('red')

    t.up()
    t.goto(x-20, y+10)
    t.down()
    t.right(45)
    t.forward(56)

    t.up()
    t.goto(x+20, y+10)
    t.down()
    t.right(90)
    t.forward(56)

def draw_o(x, y):
    t = Turtle()
    t.speed('fastest')
    t.hideturtle()
    t.color('red')
    t.up()
    t.goto(x-10, y-20)
    t.down()
    t.circle(15)

def print_board():
    vertical_line(-100, 200)
    vertical_line(0, 200)
    vertical_line(100, 200)
    vertical_line(200, 200)
    horizontal_line(-100, 200)
    horizontal_line(-100, 100)
    horizontal_line(-100, 0)
    horizontal_line(-100, -100)

def cell_available(value):
    if value == "":
        return True
    else:
        return False

def player_wins(player):

    # Horizontal win
    if a == player and b == player and c == player:
        winning_line(-50, 150, "horizontal")
        return True
    elif d == player and e == player and f == player:
        winning_line(-50, 50, "horizontal")
        return True
    elif g == player and h == player and i == player:
        winning_line(-50, -50, "horizontal")
        return True

    # Vertical win
    if a == player and d == player and g == player:
        winning_line(-50, 150, "vertical")
        return True
    elif b == player and e == player and h == player:
        winning_line(50, 150, "vertical")
        return True
    elif c == player and f == player and i == player:
        winning_line(150, 150, "vertical")
        return True

    # Diagonal win
    if a == player and e == player and i == player:
        winning_line(-50, 150, "diagonal-a-i")
        return True
    elif c == player and e == player and g == player:
        winning_line(150, 150, "diagonal-c-g")
        return True

    # Player did not win
    return False

def game_tied():
    all_cells = a + b + c + d + e + f + g + h + i
    # If all the cells have been played then it is a tie.
    # This assumes we called player_wins() before and it 
    # returned false.
    if len(all_cells) == 9:
        t.color('green')
        t.write("It's a tie", False, font=('Arial', 40, 'normal'))
        return True
    else:
        return False
    
def handle_turn(click_x, click_y):
    global turn
    global a, b, c, d, e, f, g, h, i
    global game_over

    if game_over == True:
        print("Game over!")
        return
    
    # Coordinates where we will draw the turn
    x = None
    y = None
    valid_turn = False
    cell_text = ""

    # Clicked on first row?
    if click_y >= 100 and click_y <= 200:
        # A
        if click_x >= -100 and click_x <= 0:
            x = -50
            y = 150
            if cell_available(a):
                a = turn
                valid_turn = True
                cell_text = "on cell A"
            else:
                cell_text = "cell A already taken"
        # B
        if click_x >= 0 and click_x <= 100:
            x = 50
            y = 150
            if cell_available(b):
                b = turn
                valid_turn = True
                cell_text = "on cell B"
            else:
                cell_text = "cell B already taken"
        # C 
        if click_x >= 100 and click_x <= 200:
            x = 150
            y = 150
            if cell_available(c):
                c = turn
                valid_turn = True
                cell_text = "on cell C"
            else:
                cell_text = "cell C already taken"

    # Clicked on second row?
    if click_y >= 0 and click_y <= 100:
        # D
        if click_x >= -100 and click_x <= 0:
            x = -50
            y = 50
            if cell_available(d):
                d = turn
                valid_turn = True
                cell_text = "on cell D"
            else:
                cell_text = "cell D already taken"
            
        # E 
        if click_x >= 0 and click_x <= 100:
            x = 50
            y = 50
            if cell_available(e):
                e = turn
                valid_turn = True
                cell_text = "on cell E"
            else:
                cell_text = "cell E already taken"
        # F 
        if click_x >= 100 and click_x <= 200:
            x = 150
            y = 50
            if cell_available(f):
                f = turn
                valid_turn = True
                cell_text = "on cell F"
            else:
                cell_text = "cell F already taken"

    # Clicked on third row?
    if click_y <= 0 and click_y >= -100:
        # G
        if click_x >= -100 and click_x <= 0:
            x = -50
            y = -50
            if cell_available(g):
                g = turn
                valid_turn = True
                cell_text = "on cell G"
            else:
                cell_text = "cell G already taken"
                
        # H 
        if click_x >= 0 and click_x <= 100:
            x = 50
            y = -50
            if cell_available(h):
                h = turn
                valid_turn = True
                cell_text = "on cell H"
            else:
                cell_text = "cell H already taken"

        # I 
        if click_x >= 100 and click_x <= 200:
            cell_text = "on cell I"
            x = 150
            y = -50
            if cell_available(i):
                i = turn
                valid_turn = True
                cell_text = "on cell I"
            else:
                cell_text = "cell I already taken"


    # Draw the turn (x or o) and switch to the next turn
    if valid_turn:
        if turn == "x":
            draw_x(x, y)
        else:
            draw_o(x, y)

        if player_wins(turn):
            print(f"Player {turn} wins the game!")
            game_over = True
        elif game_tied():
            print(f"It's a tie")
            game_over = True
        else:
            if turn == "x":
                turn = "o"
            else:
                turn = "x"

        # print the coordinates on the grid
        # t.up()
        # t.goto(x, y)
        # t.down()    
        # t.write(f"x = {x}, y = {y} {cell_text}")

    # print the coordinates on the terminal
    print(f"click x = {click_x}, y = {click_y} {cell_text}")
    # print(f"x = {x}, y = {y} {cell_text}")
    # print(f"  next player: {turn}")


a = ""
b = ""
c = ""
d = ""
e = ""
f = ""
g = ""
h = ""
i = ""

turn = "x"
game_over = False

t = Turtle()
t.hideturtle()
print_board()
t.screen.onscreenclick(handle_turn)
t.screen.mainloop()