pygame.init()

W = 407
H = 700
SIZE = W, H
screen = pygame.display.set_mode(SIZE)
clock = pygame.time.Clock()

# colours
RED = (255, 0, 0)
GREEN = (0, 255, 0)
BLUE = (0, 0, 255)
BACKGROUND = (80, 97, 175)
LANELINE = (133, 153, 232)

x1 = 29
lane2 = 129
lane3 = 236
x2 = 335
y = 530
width = 40
height = 60
vel = 5

toggle1 = 0
toggle2 = 0

target_x1 = 29
target_x2 = 335
vel_x = 3


def drawScene():
    screen.fill(BACKGROUND)
    pygame.draw.line(screen, LANELINE, (203, 0), (203, 700), 6)
    pygame.draw.line(screen, LANELINE, (100, 0), (100, 700), 4)
    pygame.draw.line(screen, LANELINE, (306, 0), (306, 700), 4)


# main loop
run = True
while run:
    clock.tick(30)

    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            run = False

        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_LEFT:
                toggle1 += 1
                if toggle1 % 2 == 1:
                    target_x1 +=100
                else:
                    target_x1 -= 100
            elif event.key == pygame.K_RIGHT:
                toggle2 += 1
                if toggle2 % 2 == 1:
                    target_x2 -= 100
                else:
                    target_x2 += 100


    if x1 < target_x1:
        x1 = min(x1 + vel_x, target_x1)
    else:
        x1 = max(x1 - vel_x, target_x1)

    if x2 < target_x2:
        x2 = min(x2 + vel_x, target_x2)
    else:
        x2 = max(x2 - vel_x, target_x2)


    drawScene()

    pygame.draw.rect(screen, RED, (x1, y, width, height))
    pygame.draw.rect(screen, RED, (x2, y, width, height))
    pygame.display.update()

pygame.quit()