# Scribble

import simplegui

# cells
width = 15
height = 15
scale = 9  # pixels per cell

def make_empty_grid(x, y):
    grid = []
    for r in range(x):
        row = []
        for c in range(y):
            row.append(0)
        grid.append(row)
    return grid

# Handler to draw on canvas
def draw(canvas):
  for x in range(width):
    for y in range(height):
      alive = world[x][y]
      col = 'black' if alive else 'white'
      try:
        # canvas.draw_circle(center_point, radius, line_width, line_color, fill_color)
        canvas.draw_circle([x * scale + scale//2, y * scale + scale//2], scale//2, 1, '#ccc', col)
      except Exception as e:
        # I don't get this!  About one in 1000 says that col is not set.
        col = 'red'
        canvas.draw_circle([x * scale + scale//2, y * scale + scale//2], scale//2, 1, col, col)

mouse_click_new_val = 1

def mouse_handler_click(position):
  global mouse_click_new_val
  x, y = position
  x = x // scale
  y = y // scale
  # 0 <--> 1
  world[x][y] = 1 - world[x][y]
  mouse_click_new_val = world[x][y]

def mouse_handler_drag(position):
  x, y = position
  x = x // scale
  y = y // scale
  world[x][y] = mouse_click_new_val

def init():
  global world
  world = make_empty_grid(width, height)

def main():
  # Create a frame and assign callbacks to event handlers
  frame = simplegui.create_frame("Scribble", width * scale, height * scale)
  frame.set_canvas_background('white')
  frame.set_draw_handler(draw)
  frame.set_mouseclick_handler(mouse_handler_click)
  frame.set_mousedrag_handler(mouse_handler_drag)

  init()

  # Start the frame animation
  frame.start()

if __name__ == '__main__':
    main()