#Key Balls - Using Calico Graphics

#Like bouncing balls, but they all reverse when you press a key.

from Graphics import *
from Myro import timer  #used for the animation.
import random   #random starting positions and speeds

NUMBALLS = 10
WINSIZE = 500
win = Window("Pong", WINSIZE, WINSIZE)
win.mode = "manual"  #Trick to make the animation smoother....
balls = []
dx = []
dy = []


#This function gets called when somebody releases a key while the window has the focus
def handleKeyRelease(win, event):
  #All it does is print a message and reverse the direction of the balls
  print("Key Released!", event.key)
  for idx in range(len(dy) ):
     dy[idx] = -dy[idx]
     dx[idx] = -dx[idx]


#Bind the key handler funciton! (Note that this works even after the timer runs out!)

onKeyPress( handleKeyRelease )



#make each of the balls with a random starting position and dx,dy.
for x in range(NUMBALLS):
  #Generate a random startX and startY position for this ball.
  startX = int( random.random() * WINSIZE)
  startY = int( random.random() * WINSIZE )

  #create this ball
  thisBall = Circle((startX,startY), 10)
  thisBall.draw(win)                        #Draw it on the window.
  balls.append(thisBall)                    #Add it to the list of balls.

  #make a random color for this ball:
  co = Color( random.random() * 255, random.random() *255, random.random() *255)
  thisBall.color = co

  #Generate random DX and DY for this ball, and save them to the dx and dy lists.
  ballDX = int( random.random() * 30) - 15
  ballDY = int( random.random() * 30) - 15
  dx.append(ballDX)
  dy.append(ballDY)






#Now, animate all the balls for 15 seconds:
for i in timer(15):

  #Now, move all the balls and check to make sure they don't go off the edges!
  for index in range(len(balls) ):
     b = balls[index]
     ballDX = dx[index]
     ballDY = dy[index]
     b.move(ballDX,ballDY)
     if b.getX() > WINSIZE or b.getX() < 0:
        dx[index] = -dx[index]

     if b.getY() > WINSIZE or b.getY() < 0:
        dy[index] = -dy[index]


  #Outside of the "for index of each ball" loop, but inside the timer loop.
  wait(0.1)  #Wait for 1/10th of a second so the user can see the ball moving!
  win.update()  #Because we set the window mode to manual, we must tell it when to update!