snake.py

import pygame
import sys
from pygame.math import Vector2
import random

class Garbage:
    def __init__(self):
        self.randomize()
        
    def draw_garbage(self):
        #create rectangle
        garbage_rect = pygame.Rect(self.pos.x*cell_size,self.pos.y*cell_size,cell_size,cell_size)
        screen.blit(apple,garbage_rect)
        # pygame.draw.rect(screen,(126,166,114),garbage_rect)
    def randomize(self):
        self.x = random.randint(0,cell_number -1)
        self.y = random.randint(0,cell_number -1)
        self.pos = Vector2(self.x,self.y)

class Snake:
    def __init__(self):
        self.body = [Vector2(5,10),Vector2(4,10),Vector2(3,10)]
        self.direction = Vector2(0,0)
        self.new_block = False

        self.head_up = pygame.image.load('img/head_up.png').convert_alpha()
        self.head_down = pygame.image.load('img/head_down.png').convert_alpha()
        self.head_right = pygame.image.load('img/head_right.png').convert_alpha()
        self.head_left = pygame.image.load('img/head_left.png').convert_alpha()
        
        self.tail_up = pygame.image.load('img/tail_up.png').convert_alpha()
        self.tail_down = pygame.image.load('img/tail_down.png').convert_alpha()
        self.tail_right = pygame.image.load('img/tail_right.png').convert_alpha()
        self.tail_left = pygame.image.load('img/tail_left.png').convert_alpha()
        
        self.body_vertical = pygame.image.load('img/body_vertical.png').convert_alpha()
        self.body_horizontal = pygame.image.load('img/body_horizontal.png').convert_alpha()
        
        self.body_tr = pygame.image.load('img/body_tr.png').convert_alpha()
        self.body_tl = pygame.image.load('img/body_tl.png').convert_alpha()
        self.body_br = pygame.image.load('img/body_br.png').convert_alpha()
        self.body_bl = pygame.image.load('img/body_bl.png').convert_alpha()

        self.crunch_sound = pygame.mixer.Sound('Sound/crunch.wav')

    def draw_snake(self):
        self.update_head_graphics()
        self.update_tail_graphics()
        for index,block in enumerate(self.body):
            x_pos = block.x *cell_size
            y_pos = block.y * cell_size
            block_rect = pygame.Rect(x_pos,y_pos,cell_size,cell_size)

            if index == 0:
                screen.blit(self.head,block_rect)
            elif index == len(self.body)-1:
                screen.blit(self.tail, block_rect)
            else:
                previous_block = self.body[index +1] - block
                next_block = self.body[index-1]-block
                if previous_block.x == next_block.x:
                    screen.blit(self.body_vertical,block_rect)
                elif previous_block.y == next_block.y:
                    screen.blit(self.body_horizontal,block_rect)
                else:
                    if previous_block.x == -1 and next_block.y == -1 or previous_block.y == -1 and next_block.x == -1:
                        screen.blit(self.body_tl,block_rect) 
                    elif previous_block.x == -1 and next_block.y == 1 or previous_block.y == 1 and next_block.x == -1:
                        screen.blit(self.body_bl,block_rect)
                    elif previous_block.x == 1 and next_block.y == -1 or previous_block.y == -1 and next_block.x == 1:
                        screen.blit(self.body_tr,block_rect)
                    elif previous_block.x == 1 and next_block.y == 1 or previous_block.y == 1 and next_block.x == 1:
                        screen.blit(self.body_br, block_rect)
            
    def update_tail_graphics(self):
        tail_relation = self.body[-2] - self.body[-1]
        if tail_relation == Vector2(1,0):
            self.tail = self.tail_left
        elif tail_relation == Vector2(-1,0):
            self.tail = self.tail_right
        elif tail_relation == Vector2(0,-1):
            self.tail = self.tail_down
        elif tail_relation == Vector2(0,1):
            self.tail = self.tail_up

    def update_head_graphics(self):
        head_relation = self.body[1] - self.body[0]
        if head_relation == Vector2(1,0):
            self.head = self.head_left
        elif head_relation == Vector2(-1,0):
            self.head = self.head_right
        elif head_relation == Vector2(0,-1):
            self.head = self.head_down
        elif head_relation == Vector2(0,1):
            self.head = self.head_up

    def move_snake(self):
        if self.new_block == True:
            body_copy = self.body[:]
            body_copy.insert(0,body_copy[0]+ self.direction)
            self.body = body_copy
            self.new_block = False
        else:
            body_copy = self.body[:-1]
            body_copy.insert(0,body_copy[0]+ self.direction)
            self.body = body_copy

    def play_crunch_sound(self):
        self.crunch_sound.play()

    def add_block(self):
        self.new_block = True

    def reset(self):
        self.body = [Vector2(5,10),Vector2(4,10),Vector2(3,10)]
        self.direction = Vector2(0,0)

class main:
    def __init__(self):
        self.snake = Snake()
        self.garbage = Garbage()
    
    def update(self):
        self.snake.move_snake()
        self.check_collision()
        self.check_fail()
    
    def draw_elements(self):
        self.draw_grass()
        self.garbage.draw_garbage()
        self.snake.draw_snake()
        self.draw_score()
    
    def check_collision(self):
        if self.garbage.pos == self.snake.body[0]:
            self.garbage.randomize()
            self.snake.add_block()
            self.snake.play_crunch_sound()
        for block in self.snake.body[1:]:
            if block == self.garbage.pos:
                self.garbage.randomize()

    def draw_score(self):
        score_text = str(len(self.snake.body) - 3)
        score_surface = game_font.render(score_text,True,(56,74,12))
        score_x = cell_number* cell_size - 60
        score_y = cell_number*cell_size - 40
        score_rect = score_surface.get_rect(center = (score_x,score_y)) 
        apple_rect = apple.get_rect(midright = (score_rect.left, score_rect.centery))
        bg_rect = pygame.Rect(apple_rect.left,apple_rect.top,apple_rect.width+score_rect.width+ 10,apple_rect.height)

        pygame.draw.rect(screen,(167,209,61),bg_rect)
        screen.blit(score_surface,score_rect)
        screen.blit(apple,apple_rect)
        pygame.draw.rect(screen, (56,74,12),bg_rect,2)

    def change_direction(self,direction):
        if direction == 'up' and self.snake.direction != Vector2(0,1):
            self.snake.direction = Vector2(0,-1)
            self.snake.move_snake()
        if direction == 'down' and self.snake.direction != Vector2(0,-1):
            self.snake.direction = Vector2(0,1)
            self.snake.move_snake()
        if direction == 'right' and self.snake.direction != Vector2(-1,0):
            self.snake.direction = Vector2(1,0)
            self.snake.move_snake()
        if direction == 'left' and self.snake.direction != Vector2(1,0):
            self.snake.direction = Vector2(-1,0)
            self.snake.move_snake()

    def check_fail(self, pt = None):
        if pt is None:
            pt = self.snake.body[0]

        if not 0 <= pt.x < cell_number or not 0 <= pt.y < cell_number:
            return True , 'Screen'
        if pt in self.snake.body[1:]:
            return True , 'Tail'
        return False, None

    def draw_grass(self):
        grass_colour=(167,209,61)
        for row in range(cell_number):
            if row%2 == 0:     
                for col in range(cell_number):
                    if col%2 == 0:
                        grass_rect = pygame.Rect(col*cell_size,row*cell_size,cell_size,cell_size)
                        pygame.draw.rect(screen,grass_colour,grass_rect)
            else:
                for col in range(cell_number):
                    if col%2 != 0:
                        grass_rect = pygame.Rect(col*cell_size,row*cell_size,cell_size,cell_size)
                        pygame.draw.rect(screen,grass_colour,grass_rect)
            
    def game_over(self):
        self.snake.reset()

pygame.mixer.pre_init(44100,-16,2,512)
pygame.init()
cell_size =40 
cell_number = 20
screen = pygame.display.set_mode((cell_number*cell_size,cell_number*cell_size))
clock = pygame.time.Clock()
apple = pygame.image.load('img/apple.png').convert_alpha() 
game_font = pygame.font.Font('Font/PoetsenOne-Regular.ttf',25)
main_game = main()

SCREEN_UPDATE = pygame.USEREVENT
pygame.time.set_timer(SCREEN_UPDATE,150)

while True:
    #draw all the elements
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            sys.exit()
        if event.type == SCREEN_UPDATE:
            main_game.update()
        # if event.type == pygame.KEYDOWN:
        #     if event.key == pygame.K_UP and main_game.snake.direction.y != 1:
        #         main_game.snake.direction = Vector2(0,-1)    
        #     if event.key == pygame.K_DOWN and main_game.snake.direction.y != -1:
        #         main_game.snake.direction = Vector2(0,1)
        #     if event.key == pygame.K_RIGHT and main_game.snake.direction.x != -1:
        #         main_game.snake.direction = Vector2(1,0)
        #     if event.key == pygame.K_LEFT and main_game.snake.direction.x != 1:
        #         main_game.snake.direction = Vector2(-1,0)            
    screen.fill((175,215,70))
    main_game.draw_elements()
    pygame.display.update()
    clock.tick(60)