from PIL import Image

class Screen:
  width = None
  height = None
  x0 = None
  y0 = None
  
  def __init__(self, width, height):
    self.width = width
    self.height = height
    self.x0 = int(width/2)
    self.y0 = int(height/2)
    
    self.img = Image.new( 'RGB', (self.width, self.height), "white")
    self.pixels = self.img.load()
    self.drawAxis()


  def setPoint(self, x, y, v):
    c = self.x0+x
    r = self.y0-y
    if v == "*":
      color = (0, 0, 0)
    elif v == ".":
      color = (255, 0, 0)
    else:
      color = v
      
    self.pixels[c, r] = color
 
  
  def moveOrigin(self, dx, dy):
    self.x0 += dx
    self.y0 -= dy
    
    self.img = Image.new( 'RGB', (self.width, self.height), "white")
    self.pixels = self.img.load()
    self.drawAxis()


  def drawAxis(self):
    r = self.y0
    for c in range(self.width):
      self.pixels[c,r] = (128, 128, 126)
    
    c = self.x0  
    for r in range(self.height):
      self.pixels[c,r] = (128, 128, 128)


  def printScreen(self, fileName = None):
    if fileName is not None:
      self.img.save(fileName)
    self.img.show()