Help with pygame

[Daniel Kersgaard]

I'm having a little trouble, tried Googling it, but to no avail. Currently, I'm working on making a snake game, however I'm stuck on a simple border. The only thing I need help with is when you run the program, the bottom right corner of the border is missing. I'm not sure why. And I know I'm no where near finished, I've simply got a wall, and a randomly placed piece of food. A classmate mentioned increasing the BLOCK_SIZE variable in the width for loop, but that simply moved the top and bottom walls over one pixel. I'm stuck, and any help would be greatly appreciated! And I'm not sure if there is a better or easier way of providing my code, so I just pasted it below.

import pygame as pg
import random as rnd
import sys

#define colors using rgb
RED        = (255,0,0)
RED_DARK   = (150,0,0)
GREEN      = (0,255,0)
GREEN_DARK = (0,150,0)
BLUE       = (0,0,255)
BLUE_DARK  = (0,0,150)
WHITE      = (255,255,255)
BLACK      = (0,0,0)

#block size
BLOCK_SIZE = 30


#play area and game speed
WIDTH = 25
HEIGHT = 25
SPEED = 8
SPEED_TICK =2
SPEED_NIC = 5
SHORT = 12
LONG = 1


UP = 0
DOWN = 1
LEFT = 2
RIGHT = 3


class food:

    #class constructor
    def __init__(self, surface, min_xcord, max_xcord, min_ycord, max_ycord):
        self.surface = surface
        self.min_xcord = min_xcord
        self.max_xcord = max_xcord
        self.min_ycord = min_ycord
        self.max_ycord = max_ycord

        self.apple = pg.Surface((BLOCK_SIZE, BLOCK_SIZE))
        self.apple.set_alpha(255)
        self.apple.fill(RED)
    #get food position
    def getPosition(self):
        return (rnd.randint(self.min_xcord, self.max_xcord), rnd.randint(self.min_ycord, self.max_ycord))
        
    #draw the food on the play area
    def draw(self):
        position = self.getPosition()
        
        self.surface.blit(self.apple, (position[0] * BLOCK_SIZE, position[1] * BLOCK_SIZE))

def drawWalls(surface):

    # create wall block
    wallblock = pg.Surface((BLOCK_SIZE, BLOCK_SIZE))
    wallblock.set_alpha(255)
    wallblock.fill(BLUE)
    
    #left and right walls
    for y in range(HEIGHT):
        surface.blit(wallblock, (0, y * BLOCK_SIZE))
        surface.blit(wallblock, (WIDTH * BLOCK_SIZE, y * BLOCK_SIZE))
    
        for x in range(WIDTH):
            surface.blit(wallblock, (x * BLOCK_SIZE, 0))
            surface.blit(wallblock, (x * BLOCK_SIZE, HEIGHT * BLOCK_SIZE))

    pg.display.flip()

def main():

    #initalize pygame
    pg.init()

    #initalize the main screen, screen is 'pygame.Surface'
    screen = pg.display.set_mode(((WIDTH + 1) * BLOCK_SIZE, (HEIGHT + 1) * BLOCK_SIZE))
    screen.fill(BLACK)

    drawWalls(screen)
    
    myfood = food(screen, 1, 24, 1, 24)
    myfood.draw()

    pg.display.flip()
  

main()