# File: snake2.py
#
# A simple program that uses the graphics module
# and the curses module to draw a "snake" on
# the graphics window that is controlled by 
# the arrow keys on the keyboard

from graphics import * 
import time
import curses



def main():

   def drawBox(x, y, color):
      box = Rectangle(Point(x,y), Point(x+20,y+20))
      box.setFill(color)
      box.setWidth(0)
      box.draw(win)

   # start curses 
   # don't print to screen
   # don't wait for 'enter' to be pressed
   # map special keys to curses constants

   stdscr = curses.initscr()
   curses.noecho()
   curses.cbreak()
   stdscr.keypad(1)

   # make a window for drawing stuff
   win = GraphWin("Hello", 500, 500)

   # initial position
   x = 0
   y = 240
   drawBox(x,y,"orange")

   done = False
   while not done:

      # get a character
      c = stdscr.getch()
      arrowKeyPressed = False
      new_x = x
      new_y = y

      # use arrow keys to specify
      # location of next point

      if c == curses.KEY_LEFT :
         arrowKeyPressed = True
         new_x = (x - 20) % 500
      elif c == curses.KEY_RIGHT :
         arrowKeyPressed = True
         new_x = (x + 20) % 500
      elif c == curses.KEY_UP :
         arrowKeyPressed = True
         new_y = (y - 20) % 500 
      elif c == curses.KEY_DOWN :
         arrowKeyPressed = True
         new_y = (y + 20) % 500 
      elif c == ord('q'):
         done = True

      # update box drawn if needed
      if arrowKeyPressed:

         # erase previous location
         drawBox(x,y,"white")
         # draw new box
         drawBox(new_x, new_y,"orange")
         x = new_x
         y = new_y

      time.sleep(.1)

   # end of while not done


   # wait before closing window
   time.sleep(2)

   # make the window go away
   win.close()

   # restore things to normal
   stdscr.keypad(0)
   curses.nocbreak()
   curses.echo()
   curses.endwin()

# end of main()

main()