;;; Scheme Recursive Art Contest Entry
;;;
;;; Please do not include your name or personal info in this file.
;;;
;;; Title: A Lonely Night
;;;
;;; Description:
;;;   <You might be lonely
;;;    But when everything seems dark
;;;    We are here for you.>

(define (draw)
  ; YOUR CODE HERE
  (define (draw-tree height depth x y)
  	(setheading 0)
  	(color "blue")
  	(draw-tree-base (* depth 4) depth x y)
  	(setheading 0)
  	(draw-branch height depth)
  )

  (define (draw-tree-base base trunk x y)
  	(if (<= base trunk)
  		nil
  		(begin
  			(pu)
  			(setposition x y)
	  		(pd)
	  		(setheading 90)
	  		(forward base)
	  		(draw-tree-base (* base 0.9) trunk (+ x (* base 0.05)) (+ y 1))
	  	)
	 )
  )

  (define (draw-branch len depth)
  	(pd)
  	(color "blue")
  	(draw-line len depth)
  	(cond ((<= depth 1)
  		(begin
  			(color "pink")
  			(begin_fill)
  			(circle 1.5)
  			(end_fill))
  		)
  	(else (begin
		  	(right 20)
		  	(draw-branch (quotient len 1.25) (- depth 1))
		  	(left 25)
		  	(draw-branch (quotient len 1.5) (- depth 2))
		  	(left 20)
		  	(draw-branch (quotient len 1.3) (- depth 0.5))
		  	(right 25)
  			)
  		)
  	)
  	(pu)
  	(backward len)
  )

  (define (draw-line len thickness)
  	(pd)
  	(begin_fill)
  	(forward len)
  	(left 90)
  	(forward thickness)
  	(left 90)
  	(forward len)
  	(left 90)
  	(forward thickness)
  	(end_fill)
  	(pu)
  	(left 90)
  	(forward len)
  	(pd)
  )

  (define (draw-sky)
  	(define (draw-sky-helper x y r g b)
	  	(if (>= r 1)
	  		nil
	  		(begin
	  			(color (rgb r g b))
	  			(pu)
	  			(setheading 0)
	  			(setposition x y)
	  			(left 90)
	  			(pd)
	  			(forward (* x 2))
	  			(draw-sky-helper x (- y 1) (+ r 0.003) (+ g 0.003) (+ b 0.003))
	  		)
	  	)
	  )
  	(draw-sky-helper 500 350 0 0 0)
  )

  (define (draw-ground)
  	(define (draw-ground-helper x y r g b)
	  	(if (or (>= r 1) (>= g 1) (>= b 1))
	  		nil
	  		(begin
	  			(color (rgb r g b))
	  			(pu)
	  			(setheading 0)
	  			(setposition x y)
	  			(left 90)
	  			(pd)
	  			(forward (* x 2))
	  			(draw-ground-helper x (+ y 1) (+ r 0.0005) (+ g 0.0028) (+ b 0.0005))
	  		)
	  	)
	  )
  	(draw-ground-helper 500 -330 0.8 0 0.8)
  )

  (define (draw-moon)
  	(define (draw-moon-helper x y)
  		(color "white")
  		(pu)
  		(setposition x y)
  		(setheading 270)
  		(pd)
  		(begin_fill)
  		(circle 100 200)
  		(setheading 129)
  		(circle 150 -82)
  		(end_fill)
  	)
  	(draw-moon-helper -150 280)
  )


  (speed 0)
  (hideturtle)
  (draw-sky)
  (draw-moon)
  (draw-ground)
  (pu)
  (setposition 250 -100)
  (draw-tree 75 4 250 -100)
  (setposition -150 -174)
  (draw-tree 88 5 -150 -174)
  (setposition 100 -275)
  (draw-tree 100 5 100 -275)
  (exitonclick))

; Please leave this last line alone.  You may add additional procedures above
; this line.
(draw)