import turtle

#General Shape class - base class for other shapes
class Shape(object):
	#Constructor for Shape class
	#Parameters: pencolor - color of the pen to use for outlining
	#			 pensize - size (width) of the pen to use
	#Returns: None, post-condition: instance variables for class will be set with initial values
	def __init__(self, pencolor = "black", pensize = 1):
		self.pencolor = pencolor
		self.pensize = pensize
     
        
#Line class - class used to create and draw a line object
class Line(Shape):
	# Constructor for Line class 
	#Parameters: beg - coordinates of the beginning point
	#    		 end - coordinates of the ending point
	#    		 pencolor - color of the line
	#    		 pensize - size (width) of the line
	#Returns: None, post-condition: instance variables for class will be set with initial values
	def __init__(self, beg = (0.0, 0.0), end = (50.0, 0.0), pencolor = "black", pensize = 1):
		Shape.__init__(self,pencolor,pensize)
		self.beg = beg
		self.end = end

	#Overloading the str method
	#Parameters: None
	#Returns: a nicely formatted string with start and end points
	def __str__(self):
		return "Line(beg:{},end:{})".format(self.beg,self.end)

	#Method used for drawing a Line using Turtle
	#Parameter: pen - an object of type Turtle
	#Returns: None
	def draw(self, pen):
		pen.pensize(self.pensize)
		pen.pencolor(self.pencolor)
		pen.up()
		pen.goto(self.beg)
		pen.down()
		pen.goto(self.end)

#3-D box class
class Box(object):
	#Constructor for a 3-D box
	#Parameters: pos - reference position (lower left corner of the box)
	#  	         size - length of a side of the box
	#Returns: None
	def __init__(self, pos = (0.0,0.0), size = 50):
		self.pos = pos
		x,y = pos
		self.size = size
		offset = size/3.0     # off set to use for back face   
		# an instance contains 9 lines, comments indicate: face, edge
		self.side_lines = [Line((x,y),(x,y+size)), # front, left 
                           Line((x,y),(x+size,y)), # front, bottom
                           Line((x+size,y),(x+size,y+size)),  # front, right
                           Line((x,y+size),(x+size,y+size)),  # front, top
                           Line((x,y+size),(x+offset,y+size+offset)), #top, left
                           Line((x+offset,y+size+offset),(x+size+offset,y+size+offset)), #top, back
                           Line((x+size,y+size),(x+size+offset,y+size+offset)), #top, right
                           Line((x+size,y),(x+size+offset,y+offset)),  # right, bottom
                           Line((x+size+offset,y+offset),(x+size+offset,y+size+offset)) # right, back
                           ]

	#Overloading the str method
	#Parameters: None
	#Returns: a nicely formatted string with position and size
	def __str__(self):
		return "Box(pos:{},size:{})".format(self.pos,self.size)

	#Method used for drawing a Line using Turtle
	#Parameter: pen - an object of type Turtle
	#Returns: None
	def draw(self,pen):
		for l in self.side_lines:
			l.draw(pen)

def main():
	#create an object of type Turtle
	pen = turtle.Turtle()
    
	#create a new box, print out information about the box and then draw it using the turtle
	box1 = Box()
	print(box1)
	box1.draw(pen)

	#create a second box, print out information about the box and then draw it using the turtle
	box2 = Box((80.0,0.0), 60)
	print(box2)
	box2.draw(pen)

	#create a line, print out information about the line and then draw it using the turtle
	line = Line((-100,-100),(-100,100),"purple", 3)
	print(line)
	line.draw(pen)
        
	#command makes the turtle icon disappear from the screen
	pen.hideturtle()
    
	#The turtle screen will close when you click on it.
	turtle.exitonclick()
    
main()