import math
import random
import pygame as pg
pg.init()

#init seats
seats = [0] * (7)
appr = [0] * (31)
for i in range(7):
    seats[i] = [0] * (5)

#init screen
width, height = 705, 405
screen = pg.display.set_mode((width, height))
pg.display.set_caption("Classroom")

#init background
bg = pg.Surface(screen.get_size())
bg = bg.convert()
bg.fill((0, 0, 0))

#draw game_map
def Draw() :
    x = 20
    y = 20
    for i in range(30) :
        appr[i+1] = 0
    for i in range(7) :
        for j in range(5) :
            pg.draw.rect(bg, (255,255,255),[i*100+5, j*80+5, 95, 75], 0)
            pg.draw.rect(bg, (  0,  0,  0),[i*100+5, j*80+5, 95, 75], 1)
            if (i == 0 and j == 0) :
                continue
            if (i == 6 and j == 0) :
                continue
            if (i == 0 and j == 4) :
                continue
            if (i == 3 and j == 4) :
                continue
            if (i == 6 and j == 4) :
                continue
            tmp = math.ceil(random.random()*30)
            while (appr[tmp] == 1) :
                tmp = math.ceil(random.random()*30)
            seats[i][j] = tmp
            appr[tmp] = 1
            font = pg.font.SysFont("simhei", 50)
            text = font.render(str(seats[i][j]), True, (0,0,0))
            bg.blit(text, (i*100+32, j*80+27))
    #show screen
    screen.blit(bg, (0,0))
    pg.display.update()

Draw()

#exit
running = True
while running:
    if pg.mouse.get_pressed()[0] :
        Draw()
    for event in pg.event.get():
        if event.type == pg.QUIT:
            running = False