diff --git a/commonlisp/gilded-rose-functional.lisp b/commonlisp/gilded-rose-functional.lisp new file mode 100644 index 00000000..10cd83e8 --- /dev/null +++ b/commonlisp/gilded-rose-functional.lisp @@ -0,0 +1,129 @@ +;; Hi and welcome to team Gilded Rose. As you know, we are a small inn +;; with a prime location in a prominent city ran by a friendly +;; innkeeper named Allison. We also buy and sell only the finest goods. +;; Unfortunately, our goods are constantly degrading in quality as they +;; approach their sell by date. We have a system in place that updates +;; our inventory for us. It was developed by a no-nonsense type named +;; Leeroy, who has moved on to new adventures. Your task is to add the +;; new feature to our system so that we can begin selling a new +;; category of items. + +;; First an introduction to our system: +;; All items have a SellIn value which denotes the number of days we have to sell the item +;; All items have a Quality value which denotes how valuable the item is +;; At the end of each day our system lowers both values for every item +;; Pretty simple, right? Well this is where it gets interesting: +;; Once the sell by date has passed, Quality degrades twice as fast +;; The Quality of an item is never negative +;; "Aged Brie" actually increases in Quality the older it gets +;; The Quality of an item is never more than 50 +;; "Sulfuras", being a legendary item, never has to be sold or decreases in Quality +;; "Backstage passes", like aged brie, increases in Quality as it's +;; SellIn value approaches; Quality increases by 2 when there are 10 +;; days or less and by 3 when there are 5 days or less but Quality +;; drops to 0 after the concert + +;; We have recently signed a supplier of conjured items. This requires an update to our system: +;; "Conjured" items degrade in Quality twice as fast as normal items +;; Feel free to make any changes to the UpdateQuality method and add +;; any new code as long as everything still works correctly. However, +;; do not alter the Item class or Items property as those belong to the +;; goblin in the corner who will insta-rage and one-shot you as he +;; doesn't believe in shared code ownership (you can make the +;; UpdateQuality method and Items property static if you like, we'll +;; cover for you). +;; Just for clarification, an item can never have its Quality increase +;; above 50, however "Sulfuras" is a legendary item and as such its +;; Quality is 80 and it never alters. + +;; https://github.com/emilybache/GildedRose-Refactoring-Kata + +;; Common Lisp functional version: Manfred Bergmann, 2022 + +;;; ================================================================ +;;; Code + +(defpackage :gilded-rose + (:use :cl)) + +(in-package :gilded-rose) + + +;;; Class ITEM + +(defstruct item + (name "" :type string :read-only t) + (sell-in 0 :type integer) + (quality 0 :type integer)) + +(defun update-quality (items) + (mapcar #'update-item items)) + +(defun update-item (item) + (let ((new-item (copy-structure item))) + (with-slots (name quality sell-in) new-item + (if (and (not (equalp name "Aged Brie")) + (not (equalp name "Backstage passes to a TAFKAL80ETC concert"))) + (if (> quality 0) + (if (not (equalp name "Sulfuras, Hand of Ragnaros")) + (setf quality (- quality 1)))) + (when (< quality 50) + (setf quality (+ quality 1)) + (when (equalp name "Backstage passes to a TAFKAL80ETC concert") + (if (< sell-in 11) + (if (< quality 50) + (setf quality (+ quality 1)))) + (if (< sell-in 6) + (if (< quality 50) + (setf quality (+ quality 1))))))) + + (if (not (equalp name "Sulfuras, Hand of Ragnaros")) + (setf sell-in (- sell-in 1))) + + (if (< sell-in 0) + (if (not (equalp name "Aged Brie")) + (if (not (equalp name "Backstage passes to a TAFKAL80ETC concert")) + (if (> quality 0) + (if (not (equalp name "Sulfuras, Hand of Ragnaros")) + (setf quality (- quality 1)))) + (setf quality (- quality quality))) + (if (< quality 50) + (setf quality (+ quality 1)))))) + new-item)) + +;;; Example + +(defun to-string (item) + (with-slots (name quality sell-in) item + (format nil "~a, ~a, ~a" name sell-in quality))) + +(defun print-day (day items) + (format t "-------- day ~a --------~%" day) + (format t "name, sell-in, quality~%") + (dolist (item items) + (write-line (to-string item))) + (terpri)) + +(defun run-gilded-rose (days) + (write-line "OMGHAI!") + (let* ((descriptions '(("+5 Dexterity Vest" 10 20) + ("Aged Brie" 2 0) + ("Elixir of the Mongoose" 5 7) + ("Sulfuras, Hand of Ragnaros" 0 80) + ("Sulfuras, Hand of Ragnaros" -1 80) + ("Backstage passes to a TAFKAL80ETC concert" 15 20) + ("Backstage passes to a TAFKAL80ETC concert" 10 49) + ("Backstage passes to a TAFKAL80ETC concert" 5 49) + ;; this conjured item does not work properly yet + ("Conjured Mana Cake" 3 6))) + (items (loop :for (name sell-in quality) :in descriptions + :collect (make-item :name name + :sell-in sell-in + :quality quality)))) + (loop :for day :upto days + :with the-items = items + :do (progn + (print-day day the-items) + (setf the-items (update-quality the-items)))))) + +;;; ================================================================