import turtle

wn = turtle.Screen()
wn.title("Pong by Joseph Abero")
wn.bgcolor("black")
wn.setup(width=800, height=600)
wn.tracer(0)

# Paddle A
paddle_a = turtle.Turtle()
paddle_a.speed(0)
paddle_a.shape("square")
paddle_a.color("white")
paddle_a.shapesize(stretch_wid=5, stretch_len=1)
paddle_a.penup()
paddle_a.goto(-350, 0)

# Paddle B
paddle_b = turtle.Turtle()
paddle_b.speed(0)
paddle_b.shape("square")
paddle_b.color("white")
paddle_b.shapesize(stretch_wid=5, stretch_len=1)
paddle_b.penup()
paddle_b.goto(350, 0)

# Ball
ball = turtle.Turtle()
ball.speed(0)
ball.shape("square")
ball.color("white")
ball.penup()
ball.goto(0, 0)
ball.dx = .3
ball.dy = .3


# Functions
def paddle_a_up():
	y = paddle_a.ycor()
	if (y + 20) > 300:
		paddle_a.sety(300)
	else: 
		paddle_a.sety(y + 20)


def paddle_a_down():
	y = paddle_a.ycor()
	if (y - 20) < -300:
		paddle_a.sety(-300)
	else: 
		paddle_a.sety(y - 20)

def paddle_b_up():
	y = paddle_b.ycor()
	if (y + 20) > 300:
		paddle_b.sety(300)
	else: 
		paddle_b.sety(y + 20)


def paddle_b_down():
	y = paddle_b.ycor()
	if (y - 20) < -300:
		paddle_b.sety(-300)
	else: 
		paddle_b.sety(y - 20)

# Keyboard Bindings
wn.listen()
wn.onkeypress(paddle_a_up, "w")
wn.onkeypress(paddle_a_down, "s")
wn.onkeypress(paddle_b_up, "e")
wn.onkeypress(paddle_b_down, "d")

# Main Game Loop
while True:
	wn.update()

	# Move the ball
	ball.setx(ball.xcor() + ball.dx)
	ball.sety(ball.ycor() + ball.dy)

	# Border checking
	if ball.ycor() > 290:
		ball.sety(290)
		ball.dy *= -1
	elif ball.ycor() < -290:
		ball.sety(-290)
		ball.dy *= -1
	elif ball.xcor() > 390:
		ball.setx(390)
		ball.dx *= -1
	elif ball.xcor() < -390:
		ball.setx(-390)
		ball.dx *= -1

	# Paddle and ball collisions
	if (ball.xcor() > 340 and ball.xcor() < 350 and 
		ball.ycor() < paddle_b.ycor() + 40 and 
		ball.ycor() > paddle_b.ycor() - 40):
			ball.setx(340)
			ball.dx *= -1
	if (ball.xcor() < -340 and ball.xcor() > -350 and
		ball.ycor() < paddle_a.ycor() + 40 and 
		ball.ycor() > paddle_a.ycor() - 40):
			ball.setx(-340)
			ball.dx *= -1
