import pygame,sys,random,os
from pygame.locals import *

def main():
    os.environ["SDL_VIDEO_CENTERED"] = "1"
    pygame.init()
    pygame.display.set_caption("SNAKE")
    screen = pygame.display.set_mode((320,320))
    snakeHead = [160,304]
    snakeBody = [[160,304],[144,304],[128,304]]
    angle = 0
    snakeDead = False
    while 1:
        while snakeDead == False:
            for e in pygame.event.get():
                if e.type == QUIT:
                    pygame.quit()
                    return
                if e.type == KEYDOWN:
                    if e.key == K_ESCAPE:
                        pygame.quit()
                        return
                    if e.key == K_UP:
                        angle = 0
                    if e.key == K_LEFT:
                        angle = 90
                    if e.key == K_DOWN:
                        angle = 180
                    if e.key == K_RIGHT:
                        angle = 270

            update(angle, snakeHead,snakeBody,snakeDead)
            screen.fill((255,255,255))
            draw(screen,snakeBody,snakeHead)
            pygame.display.update()
            pygame.time.wait(100)
        if snakeDead == True:
            font = pygame.font.SysFont("arial",48)
            ren = font.render("GAME OVER",True,(0,255,0))
            screen.blit(ren,(5,5))
            pygame.display.update()
            pygame.time.wait(10000)
                
def update(angle,snakeHead,snakeBody,snakeDead):
    snakeBody.insert(0, list(snakeHead))
    snakeBody.pop()
    if angle == 0:
        snakeHead[1] -= 16
    if angle == 90:
        snakeHead[0] -=16
    if angle == 180:
       snakeHead[1] += 16
    if angle == 270:
        snakeHead[0] += 16

    for b in snakeBody:
        if snakeHead == b:
            snakeDead = True
    if snakeHead[0] not in range(320):
        snakeDead =  True
    if snakeHead[1] not in range(320):
        snakeDead = True

def draw(screen,snakeBody,snakeHead):
    screen.fill((255,0,0),(snakeHead[0],snakeHead[1], 16,16))
    for b in snakeBody:
        screen.fill((255,0,0),(b[0],b[1],16,16))

        
if __name__ == "__main__":
    main()