import pygame

# Homework: move a shape with the arrow keys.
# Use pygame.key.get_pressed() and the constants:
#   pygame.K_LEFT, pygame.K_RIGHT, pygame.K_UP, pygame.K_DOWN
# The shape should wrap around: when it exits one edge it reappears
# on the opposite side.

pygame.init()

screen = pygame.display.set_mode((640, 480))
pygame.display.set_caption("Arrow Keys")
clock = pygame.time.Clock()

BG   = (20, 20, 20)
RED  = (220, 60, 60)

RADIUS = 25
x = 320.0
y = 240.0
speed = 5

running = True
while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False

    keys = pygame.key.get_pressed()
    # TODO: update x and y based on arrow key presses
    # TODO: wrap x: if x < -RADIUS then x = 640 + RADIUS, and vice versa
    # TODO: wrap y: if y < -RADIUS then y = 480 + RADIUS, and vice versa

    screen.fill(BG)
    pygame.draw.circle(screen, RED, (int(x), int(y)), RADIUS)
    pygame.display.flip()
    clock.tick(60)

pygame.quit()