;; The first three lines of this file were inserted by DrRacket. They record metadata
;; about the language level of this file in a form that our tools can easily process.
#reader(lib "htdp-beginner-reader.ss" "lang")((modname list-linear-struct) (read-case-sensitive #t) (teachpacks ()) (htdp-settings #(#t constructor repeating-decimal #f #t none #f () #f)))

;; [See note on hws page, about downloading (not pasting) .rkt files.]

; Data Definiton:
(define-struct book (title author num-pages is-copyrighted?))
;   make-book : string, string, natural, boolean -> book




;;; Data Def'n:
; A monst-def ("monster defender") is either:
;  - String
;  - Book
;  - (make-amplifier [number] [MonstDef] [String])
;   interpretation: an amplifier is a device that lets you plug in
;   some other monster-defender, and it amplifies it by `strength`.
;   When using it, it makes a sound.
;   Of course, because amplifiers are themselves monst-defs, you can plug one amplifier into another.

(define-struct amplifier (strength def sound))



;;; TASK: write examples of the data
























"go away you wicked monster!"
"shoo!"
(make-book "The Cat in the Hat" "Seuss" 37 #true)
(make-amplifier 17 "shoo!" "cough")
(make-amplifier 2
                (make-amplifier 17 "shoo!" "cough")
                "clink-clank")

(make-amplifier 0
                (make-amplifier 2
                                (make-amplifier 17 "shoo!" "cough")
                                "clink-clank")
                "oops")

; We  could draw these as trees...
; but really they'd always be long sparse trees.
; In spirit, they are actually lists.





;;; TASK write the template for func-for-monst-def



















; func-for-monst-def : monst-def -> ??
;
(define (func-for-monst-def a-md)
  (cond [(string? a-md)    ...]
        [(book? a-md)      (book-title a-md)
                           (book-author a-md)
                           (book-num-pages a-md)
                           (book-is-copyrighted? a-md)]
        [(amplifier? a-md) (amplifier-strength a-md)
                           (func-for-monst-def (amplifier-def a-md))
                           (amplifier-sound a-md)]))


; TASK: Write   effectiveness : monst-def -> number?
; We say that the effectiveness of a monster-defender is:
;   - (for strings) the length of the string you shout (f
;   - (for books) the #pages of the book, plus 10 if it's copyrighted
;   - (for amplifiers) the amplifier-strength times the strength of the internal monster-defender, minus the
;     number of characters in its sound.

















(check-expect (effectiveness "go away you wicked monster!") 27)
(check-expect (effectiveness "shoo!") 4)
(check-expect (effectiveness (make-book "The Cat in the Hat" "Seuss" 37 #true)) 47)
(check-expect (effectiveness (make-book "The Soul of Wit" "Barland" 0 #false) 0))
(check-expect (effectiveness (make-book "Chat Roulette for Dummies" "Sir Preiz" 23 #false) 23))
(check-expect (effectiveness (make-amplifier 17 "shoo!" "k-k-k")) (- (* 17 (strength "shoo!")) 5))
(check-expect (effectiveness (make-amplifier 17 (make-book "The Cat in the Hat" "Seuss" 37 #true)) "k-k-k")) (- (* 17 (strength "shoo!")) 5))

(check-expect (effectiveness (make-amplifier 2
                                             (make-amplifier 17 "shoo!" "cough")
                                             "clink-clank"))
              (- (* 2 (effectiveness (make-amplifier 17 "shoo!" "cough"))) 11))

(check-expect (effectiveness (make-amplifier 0
                                             (make-amplifier 2
                                                             (make-amplifier 17 "shoo!" "cough")
                                                             "clink-clank")
                                             "oops"))
              -4)

(check-expect (effectiveness (make-amplifier 3
                                             (make-amplifier 2
                                                             (make-amplifier 17 "shoo!" "cough")
                                                             "clink-clank")
                                             "pew, pew"))
              (- (* 3 (effectiveness  (make-amplifier 2
                                                             (make-amplifier 17 "shoo!" "cough")
                                                             "clink-clank")))
                 8))




; TASK:  Write total-sound : monst-def -> string
; Return the sound made, when using a mosnst-def.
; This is:
;  - (for strings) the string itself (it's being shouted!)
;  - (for books) the string "(flip, flip)", the sound of pages being turned
;    [alternately: make it a string of "."s, one for each page]
;  - (for amplifiers): the amplifier's `sound` followed by the total-sound of its `def` followed by its `sound` (again).