;;; Scheme Recursive Art Contest Entry
;;;
;;; Please do not include your name or personal info in this file.
;;;
;;; Title: 'Welcome to Berkeley'
;;;
;;; Description:
;;;   When the fog comes
;;;   The red sun yields even when Carol Christ stands
;;;   'Welcome to Berkeley'

;;; utilities
(define (paint-prep col) (pendown) (color col) (begin_fill))
(define (cadr lst) (car (cdr lst)))
(define (caddr lst) (cadr (cdr lst)))

;;; color utlities ;;;

(define (lighter color-string)
  (define red (gradient (car color-string)))
  (define green (gradient (cadr color-string)))
  (define blue (gradient (caddr color-string)))
  (cons (rgb red green blue) 
    (cons (list red green blue) nil))
  )

(define (gradient col)
  (if (> col 0.95) 1
  (+ col 0.05)))

(define (shades col) (cons-stream (rgb-convert col) 
  (shades (cadr (lighter col)))))

(define (rgb-convert color-string)
    (rgb (car color-string) (cadr color-string) (caddr color-string)))

; color palettes
(define sun-col (shades '(0.9 0.02 0.01)))
(define tower-col (shades '(0.85 0.72 0.44)))
(define clock-col (shades '(0.55 0.66 0.9)))
(define sky-col (shades '(0.3 0.45 0.85)))
(define fog-col (shades '(0.45 0.45 0.45)))

;;; sky ;;;
(define (sky)
    (define (sky-painter col pos_x pos_y n)
    (if (= n 0) nil 
      (begin
      (penup) (setpos pos_x pos_y) (setheading 180) (paint-prep (car col))
      (forward 200) (left 90) (forward 900) (left 90) (forward 200) (end_fill)
      (sky-painter (cdr-stream col) pos_x (- pos_y 200) (- n 1)))))
  (sky-painter sky-col -450 450 5))

; red circular sun with degrading color
(define (sun) (sky) (sun-painter 0 sun-col))

(define (sun-painter i col-string)
    (if (= i 5) nil
      (begin (penup) (setpos 150 (+ 100 (* i 20))) (setheading 90) 
        (paint-prep (car col-string)) 
        (circle (- 80 (* 20 i))) (end_fill)
        (sun-painter (+ i 1) (cdr-stream col-string)))))

;;; campanile ;;;

(define (campanile)
  (rec-block) (shading 180) 
    (window -145 115) (window -90 115) (window -35 115) 
      (clock) (tower-top))

; rectangular block of the top 180*200
; start (-200 150), end (-200 -50)
(define (rec-block) (penup)
    (setpos -200 150) (paint-prep "white") (setheading 90) (forward 180) (right 90)
    (forward 200) (right 90) (forward 180) (end_fill)
    )

; 3 windows with dark blue shading, 20-r semi-circle and 40*130 window ceils
; #1: (-145 115) #2: (-90 115) #3: (-35 115)
(define (window pos_x pos_y)
  (penup) (setpos pos_x pos_y) (setheading 0) (paint-prep "grey")
    (circle 20 180) (setheading 180) (forward 130) (left 90) (forward 40) 
      (end_fill))

; shading based on width of building
(define (shading weidth)
    (define (shade-painter n)
    (if (= n 0) nil
      (begin (forward weidth) (left 90)
          (forward 7.5) (left 90) (shade-painter (- n 1)))))
      (setheading 90) (paint-prep "#9F9788")
      (shade-painter 2) (end_fill))

; tower top, maybe use mirroring
(define (tower-top)
    (penup) (setpos -210 150) (setheading 90) (paint-prep "white") (forward 200) 
      (left 90) (forward 54.64) (left 150) (forward 40) (right 60) (forward 160) 
        (right 60) (forward 40) (left 150) (forward 54.64) (end_fill) (shading 200) (top))

; triangular top with graduate shading, 50 degree angle
(define (top)
  (define (top-painter bottom col pos_x pos_y)
    (if (< (- bottom 33.8) 0) nil
    (begin
      (penup) (setpos pos_x pos_y) (paint-prep (car col)) (setheading 90)
        (forward bottom) (left 115) (forward 40) (left 65) (forward (- bottom 33.8))
        (end_fill) 
      (top-painter (- bottom 33.8) (cdr-stream col) (+ pos_x 16.9) (+ pos_y 36.26)))))
  (top-painter 160 tower-col -190 170))

; clock body with graduated shading
(define (clock)
  (clock-body 0 170 clock-col) (clock-plate))

(define (clock-body i length col-string)
      (if (= i 7) nil
        (clock-body (+ i 1)
          (rec-drawer (car col-string) (- (- 195) (* i 3.486)) (- (- 50) (* i 39.847)) length)
          (cdr-stream col-string))
      ))

; body of the window panels
(define (rec-drawer col pos_x pos_y length)
  (penup) (setpos pos_x pos_y) (setheading 185) (paint-prep col)
  (forward 40) (setheading 90) (forward (+ length 1.396)) (setheading -5) (forward 40)
  (end_fill) (+ length 6.972))

; clock, 60-r circle and 2 needles
(define (clock-plate) (penup) (setpos -110 -200) (paint-prep "white") (setheading 90)
  (circle 50) (end_fill) (paint-prep "grey") (circle 50)
   (penup) (setpos -110 -105) (setheading 180) (pendown) 
    (color "black")
    (forward 48) (left 90) (forward 30))

;;; fog ;;;

(define (fog i col)
    (if (= i 7) nil
      (begin
  (paint-fog (car col) (+ 300 (* i 50)) (- 300 (* i 100)))
  (paint-fog (car col) (- 350 (* i 150)) (* i 25))
  (fog (+ i 1) (cdr-stream col)))))

(define (paint-fog col pos_x pos_y) 
  (penup) (setpos pos_x pos_y) (paint-prep col) (setheading -60)
  (define (fog-painter n)
    (cond 
      ((= n 0) (setheading 90) (forward 900))
      ((= 0 (remainder n 4))
        (circle 100 60) (circle 35 90) (circle 140 45)
         (fog-painter (- n 1)))
      ((= 0 (remainder n 6))
        (forward 200) (circle 10 180)
         (fog-painter (- n 1)))
      ((= 0 (remainder n 2))
      (circle 40 60) (circle 15 90) (circle 75 30) (fog-painter (- n 1)))
      (else
        (forward 100) (circle -15 178) (fog-painter (- n 1)))
        ))
  (fog-painter 12)
      (end_fill) (penup))

;; drawing time!
(define (draw)
  (speed 10)
  (sun)
  (campanile)
  (fog 0 fog-col)
  (exitonclick)
  )

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