import pygame
import random
import sys

pygame.init()
pygame.font.init()

WIDTH, HEIGHT = 1000, 800

screen = pygame.display.set_mode((WIDTH, HEIGHT))
pygame.display.set_caption("Snake Game")

BLACK = (0, 0, 0)
WHITE = (255, 255, 255)
RED = (255, 0, 0)
GREEN = (0, 255, 0)

BLOCK_SIZE = 20
SPEED = 5

clock = pygame.time.Clock()
try:
    font = pygame.font.SysFont('arial', 35)
except:
    font = pygame.font.Font(None, 35)


def show_score(score):
    text = font.render(f"Score: {score}", True, WHITE)
    screen.blit(text, [0, 0])


def draw_snake(block_size, snake_list):
    for pos in snake_list:
        pygame.draw.rect(screen, GREEN, [pos[0], pos[1], block_size, block_size])


def game_loop():
    game_over = False
    game_close = False

    x, y = WIDTH // 2, HEIGHT // 2
    dx, dy = 0, 0

    snake_body = []
    snake_len = 1

    food_x = round(random.randrange(0, WIDTH - BLOCK_SIZE) / BLOCK_SIZE) * BLOCK_SIZE
    food_y = round(random.randrange(0, HEIGHT - BLOCK_SIZE) / BLOCK_SIZE) * BLOCK_SIZE

    while not game_over:
        while game_close:
            screen.fill(BLACK)
            tip = font.render("Game Over! Q-Quit | C-Restart", True, RED)
            screen.blit(tip, (40, 130))
            show_score(snake_len - 1)
            pygame.display.update()

            for event in pygame.event.get():
                if event.type == pygame.KEYDOWN:
                    if event.key == pygame.K_q:
                        game_over = True
                        game_close = False
                    if event.key == pygame.K_c:
                        game_loop()
                if event.type == pygame.QUIT:
                    game_over = True
                    game_close = False

        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                game_over = True
            if event.type == pygame.KEYDOWN:
                if event.key == pygame.K_LEFT and dx != BLOCK_SIZE:
                    dx = -BLOCK_SIZE
                    dy = 0
                elif event.key == pygame.K_RIGHT and dx != -BLOCK_SIZE:
                    dx = BLOCK_SIZE
                    dy = 0
                elif event.key == pygame.K_UP and dy != BLOCK_SIZE:
                    dy = -BLOCK_SIZE
                    dx = 0
                elif event.key == pygame.K_DOWN and dy != -BLOCK_SIZE:
                    dy = BLOCK_SIZE
                    dx = 0

        if x < 0 or x >= WIDTH or y < 0 or y >= HEIGHT:
            game_close = True

        x += dx
        y += dy
        screen.fill(BLACK)

        pygame.draw.rect(screen, RED, [food_x, food_y, BLOCK_SIZE, BLOCK_SIZE])

        head = [x, y]
        snake_body.append(head)

        if len(snake_body) > snake_len:
            del snake_body[0]

        for seg in snake_body[:-1]:
            if seg == head:
                game_close = True

        draw_snake(BLOCK_SIZE, snake_body)
        show_score(snake_len - 1)

        pygame.display.update()

        if x == food_x and y == food_y:
            food_x = round(random.randrange(0, WIDTH - BLOCK_SIZE) / BLOCK_SIZE) * BLOCK_SIZE
            food_y = round(random.randrange(0, HEIGHT - BLOCK_SIZE) / BLOCK_SIZE) * BLOCK_SIZE
            snake_len += 1

        clock.tick(SPEED)

    pygame.quit()
    sys.exit()


if __name__ == "__main__":
    game_loop()