import os, sys
import math
import pygame
import json
from pygame.locals import *
from pygame.gfxdraw import *
from pygame.key import *

pygame.init()
screen = pygame.display.set_mode((1024, 768))
pygame.mouse.set_visible(0)

clock = pygame.time.Clock()

bat_x = 512 # 1024 / 2
bat_y = 700
bat_w = 150
bat_h =  30

bat_speed_max = 10
bat_speed_acc = 2
bat_speed_cur = 0

running = True
while running:
    clock.tick(24) # Simulate Raspberry Pi's low fps

    keys = pygame.key.get_pressed()

    if keys[K_LEFT]:
        bat_speed_cur -= bat_speed_acc
    elif keys[K_RIGHT]:
        bat_speed_cur += bat_speed_acc
    else:
        bat_speed_cur *= 0.4

    if bat_speed_cur < -bat_speed_max:
        bat_speed_cur = -bat_speed_max
    elif bat_speed_cur > bat_speed_max:
        bat_speed_cur = bat_speed_max
    elif abs(bat_speed_cur) < 0.1:
        bat_speed_cur = 0

    bat_x += bat_speed_cur
    bat_x = round(bat_x)

    background = pygame.Surface(screen.get_size())
    background = background.convert()
    background.fill((200, 200, 200))

    pygame.gfxdraw.box(background, (10, 10, 1004, 748), (100, 0, 0))

    pygame.gfxdraw.box(background, (bat_x - bat_w/2, bat_y, bat_w, bat_h), (200, 200, 200))


    if pygame.font:
        font = pygame.font.Font(None, 36)
        text = font.render(json.dumps([bat_speed_max, bat_speed_acc, bat_speed_cur]), 1, (200, 200, 200))
        background.blit(text, (20, 20))


    screen.blit(background, (0, 0))
    pygame.display.flip()

    for event in pygame.event.get():
        if event.type == QUIT:
            running = False
        elif event.type == KEYDOWN and event.key == K_ESCAPE:
            running = False