snakeGame.py

import pygame
import time
import random

snake_speed = 15

window_x = 720
window_y = 480

black = pygame.Color(0, 0, 0)
white = pygame.Color(255, 255, 255)
red = pygame.Color(255, 0, 0)
green = pygame.Color(0, 255, 0)

pygame.init()

pygame.display.set_caption("Snake")
game_window = pygame.display.set_mode((window_x, window_y))

fps = pygame.time.Clock()

snake_position = [100, 50]

snake_body = [[100, 50],
              [90, 50],
              [80, 50],
              [70, 50]
              ]

fruit_position = [random.randrange(1, (window_x//10)) * 10, 
                  random.randrange(1, (window_y//10)) * 10]

fruit_spawn = True

direction = 'RIGHT'
change_to = direction

score = 0

def show_score(choice, color, font, size):
  
    score_font = pygame.font.SysFont(font, size)
    
    score_surface = score_font.render('Score : ' + str(score), True, color)
    
    score_rect = score_surface.get_rect()
    
    game_window.blit(score_surface, score_rect)

def game_over():
  
    my_font = pygame.font.SysFont("times new roman", 50)
    
    game_over_surface = my_font.render(
        "Your Score is : " + str(score), True, red)
    
    game_over_rect = game_over_surface.get_rect()
    
    game_over_rect.midtop = (window_x/2, window_y/4)
    
    game_window.blit(game_over_surface, game_over_rect)
    pygame.display.flip()
    
    time.sleep(2)
    
    pygame.quit()
    
    quit()


while True:
    
    for event in pygame.event.get():
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_UP:
                change_to = "UP"
            if event.key == pygame.K_DOWN:
                change_to = "DOWN"
            if event.key == pygame.K_LEFT:
                change_to = "LEFT"
            if event.key == pygame.K_RIGHT:
                change_to = "RIGHT"

    if change_to == "UP" and direction != "DOWN":
        direction = "UP"
    if change_to == "DOWN" and direction != "UP":
        direction = "DOWN"
    if change_to == "LEFT" and direction != "RIGHT":
        direction = "LEFT"
    if change_to == "RIGHT" and direction != "LEFT":
        direction = "RIGHT"

    if direction == "UP":
        snake_position[1] -= 10
    if direction == "DOWN":
        snake_position[1] += 10
    if direction == "LEFT":
        snake_position[0] -= 10
    if direction == "RIGHT":
        snake_position[0] += 10

    snake_body.insert(0, list(snake_position))
    if snake_position[0] == fruit_position[0] and snake_position[1] == fruit_position[1]:
        score += 10
        fruit_spawn = False
    else:
        snake_body.pop()
        
    if not fruit_spawn:
        fruit_position = [random.randrange(1, (window_x//10)) * 10, 
                          random.randrange(1, (window_y//10)) * 10]
        
    fruit_spawn = True
    game_window.fill(black)
    
    for pos in snake_body:
        pygame.draw.rect(game_window, green,
                         pygame.Rect(pos[0], pos[1], 10, 10))
    pygame.draw.rect(game_window, white, pygame.Rect(
        fruit_position[0], fruit_position[1], 10, 10))

    if snake_position[0] < 0 or snake_position[0] > window_x-10:
        game_over()
    if snake_position[1] < 0 or snake_position[1] > window_y-10:
        game_over()

    for block in snake_body[1:]:
        if snake_position[0] == block[0] and snake_position[1] == block[1]:
            game_over()

    show_score(1, white, "times new roman", 20)

    pygame.display.update()

    fps.tick(snake_speed)