SNAKE GAME_TKINTER

# SNAKE GAME

import tkinter as tk
from tkinter import *
from tkinter import messagebox
import random

root = tk.Tk()
root.title("Snake Game")
root.configure(bg="light green")


def start():
    global variable, apple, score
    #for arrow precision
    variable = 0
    
    #game variables
    score = 0
    grid_limitx=40
    grid_limity=25
    speed = 100


    #root.maxsize(width=grid_limitx*26, height=grid_limity*30)
    #root.minsize(width=grid_limitx*26, height=grid_limity*30)

    #grid system visualization
    for i in range(grid_limitx):
        l = Button(root, text=i, width=2, height=1, bg="grey")
        l.grid(row=grid_limity, column=i)
        
        l = Button(root, text=i, width=2, height=1, bg="grey")
        l.grid(row=0, column=i)
    for i in range(grid_limity):
        l = Button(root, text=i, width=2, height=1, bg="grey")
        l.grid(row=i, column=0)
        
        l = Button(root, text=i+1, width=2, height=1, bg="grey")
        l.grid(row=i+1, column=grid_limitx)
        
        
    '''
    for i in range(len(word)):
        if i%2==0:
            l = Button(root, text=word[i], width=2, height=1, bg="dark green")
            l.grid(row=i+1, column=grid_limit, sticky=E)
        else:
            l = Button(root, text=word[i], width=2, height=1, bg="green")
            l.grid(row=i+1, column=11, sticky=E)
    '''
    #starting btn
    btn = Button(root, text="  :", bg="dark green", width=2)
    btn.grid(row=grid_limity//2, column=grid_limitx//2)
    
    def score_update():
        global scr_l
        root.title("Snake Game"+" "*grid_limitx+"Score: "+str(score))
        '''
        scr_l = Label(root, text="Score: "+str(score), bg="yellow")
        scr_l.grid(row=0, column=11)
        '''
    score_update()

    #apple poition
    apple_pos = [(i, j) for i in range(1, grid_limity-1) for j in range(1, grid_limitx-1)]
    random.shuffle(apple_pos)

    #lists
    bodies = [] #snake bodies
    body_pos = [] #position for bodies
    current = [] #current apple position

    #apple
    apple = Button(root, text="", bg="red", width=2)
    apple.grid(row=apple_pos[0][0], column=apple_pos[0][1])
    current.append((apple.grid_info()["row"], apple.grid_info()["column"]))
    #messagebox.showinfo("Notification", "Snake Game\nBy Allen J")
    #eat
    def eat():
        global apple,score
        #if snake head position in current apple position
        if (btn.grid_info()["row"], btn.grid_info()["column"]) in current:
            apple.destroy()
            
            score+=1
            #scr_l.destroy()
            score_update()
            current.clear()
            
            #adding a body
            
            if len(bodies)%2==0:
                btn1 = Button(root, text="  ", bg="green", width=2)
                btn1.grid(row=body_pos[0][0], column=body_pos[0][1])
                bodies.append(btn1)
            else:
                btn1 = Button(root, text="  ", bg="dark green", width=2)
                btn1.grid(row=body_pos[0][0], column=body_pos[0][1])
                bodies.append(btn1)
            print(len(bodies))
            
            #random apple position
            apple = Button(root, text="", bg="red", width=2)
            random.shuffle(apple_pos)

            #to check if apple position in snake body position
            def check():
                if (apple_pos[0][0], apple_pos[0][1]) in body_pos:
                    random.shuffle(apple_pos)
                    check()
                else:
                    apple.grid(row=apple_pos[0][0], column=apple_pos[0][1])
            check()
            current.append((apple.grid_info()["row"], apple.grid_info()["column"]))
        else:
            #removing the unnecessary body position(snake body wont use this)
            body_pos.pop(0)

    #left arrow
    def left_arrow(event):
        global variable
        variable=1
        def left():
            if variable==1:
                print("left")
                btn.configure(text=":  ")

                #if snake head not touching border and snake body
                if btn.grid_info()["column"]-1>=1 and (btn.grid_info()["row"], btn.grid_info()["column"]-1) not in body_pos:
                    btn.grid_configure(row=btn.grid_info()["row"], column=btn.grid_info()["column"]-1)
                    body_pos.append((btn.grid_info()["row"], btn.grid_info()["column"]))
                    
                    #each snake body to move in previous position of previous snake body
                    for i in range(len(bodies)):
                        bodies[i].grid_configure(row=body_pos[-(i+2)][0], column=body_pos[ -(i+2)][1])
                    print(body_pos)

                    #if left arrow pressed, cannot press again, cannot press right arrow, can only press up and down arrows
                    if variable==1:
                        root.bind('<Down>', down_arrow)
                        root.bind('<Up>', up_arrow)
                        root.unbind('<Left>')
                        root.unbind('<Right>')

                        root.after(speed, left)
                    else:
                        root.bind('<Left>', left_arrow)
                        root.bind('<Right>', right_arrow)
                else:
                    print("Lose!")
                    restart()
                eat()
        left()

    #right arrow
    def right_arrow(event):
        global variable
        variable=2
        def right():
            if variable==2:   
                print("right")
                btn.configure(text="  :")

                #if snake head not touching border and snake body
                if btn.grid_info()["column"]+1<=grid_limitx-1 and (btn.grid_info()["row"], btn.grid_info()["column"]+1) not in body_pos:
                    btn.grid_configure(row=btn.grid_info()["row"], column=btn.grid_info()["column"]+1)
                    body_pos.append((btn.grid_info()["row"], btn.grid_info()["column"]))

                    #each snake body to move in previous position of previous snake body
                    for i in range(len(bodies)):
                        bodies[i].grid_configure(row=body_pos[-(i+2)][0], column=body_pos[-(i+2)][1])
                    print(body_pos)

                    #if right arrow pressed, cannot press again, cannot press left arrow, can only press up and down arrows
                    if variable==2:
                        root.bind('<Down>', down_arrow)
                        root.bind('<Up>', up_arrow)
                        root.unbind('<Right>')
                        root.unbind('<Left>')

                        root.after(speed, right)
                    else:
                        root.bind('<Right>', right_arrow)
                        root.bind('<Left>', left_arrow)
                else:
                    print("Lose!")
                    restart()
                eat()
        right()

    #up arrow
    def up_arrow(event):
        global variable
        variable=3
        def up():
            if variable==3:
                print("up")
                btn.configure(text="..")

                #if snake head not touching border and snake body
                if btn.grid_info()["row"]-1>=1 and (btn.grid_info()["row"]-1, btn.grid_info()["column"]) not in body_pos:
                    btn.grid_configure(row=btn.grid_info()["row"]-1, column=btn.grid_info()["column"])
                    body_pos.append((btn.grid_info()["row"], btn.grid_info()["column"]))

                    #each snake body to move in previous position of previous snake body
                    for i in range(len(bodies)):
                        bodies[i].grid_configure(row=body_pos[-(i+2)][0], column=body_pos[-(i+2)][1])
                    
                    #if up arrow pressed, cannot press again, cannot press down arrow, can only press left and right arrows
                    if variable==3:
                        root.unbind('<Up>')
                        root.unbind('<Down>')
                        root.bind('<Left>', left_arrow)
                        root.bind('<Right>', right_arrow)

                        root.after(speed, up)
                    else:
                        root.bind('<Up>', up_arrow)
                        root.bind('<Down>', down_arrow)
                    print(body_pos) 
                else:
                    print("Lose!")
                    restart()
                eat()
        up()

    #down arrow
    def down_arrow(event):
        global variable
        variable=4
        def down():
            if variable==4:
                print("down")
                btn.configure(text="..")

                #if snake head not touching border and snake body
                if btn.grid_info()["row"]+1<=grid_limity-1 and (btn.grid_info()["row"]+1, btn.grid_info()["column"]) not in body_pos:
                    btn.grid_configure(row=btn.grid_info()["row"]+1, column=btn.grid_info()["column"])
                    body_pos.append((btn.grid_info()["row"], btn.grid_info()["column"]))

                    #each snake body to move in previous position of previous snake body
                    for i in range(len(bodies)):
                        bodies[i].grid_configure(row=body_pos[-(i+2)][0], column=body_pos[-(i+2)][1])

                    #if down arrow pressed, cannot press again, cannot press up arrow, can only press left and right arrows
                    if variable==4:
                        root.unbind('<Down>')
                        root.unbind('<Up>')
                        root.bind('<Left>', left_arrow)
                        root.bind('<Right>', right_arrow)

                        root.after(speed, down)
                    else:
                        root.bind('<Down>', down_arrow)
                        root.bind('<Up>', up_arrow)
                    print(body_pos) 
                else:
                    print("Lose!")
                    restart()
                eat()
        down()
    
    def restart():
        messagebox.showinfo("Notification", "Game Over \nScore: "+str(score))
        btn.destroy()
        apple.destroy()
        
        for body in bodies:
            body.destroy()
        bodies.clear()
        body_pos.clear()
        current.clear()
        start()

    def pause(event):
        global variable
        variable=0
        messagebox.showinfo("Notification", "Game Paused")

    #binding root to the arrow keys
    root.bind('<Left>', left_arrow)
    root.bind('<Right>', right_arrow)
    root.bind('<Up>', up_arrow)
    root.bind('<Down>', down_arrow)
    root.bind('<p>', pause)   
start()

root.mainloop()