lisp_subdecadence/src/utilities.lisp

(in-package #:subdecadence.utilities)

;;; base-deck is the unshuffled deck
;;; ♣ / C = Mj+
;;; ♠ / S = Mj-
;;; ♥ / H = Mn+
;;; ♦ / D = Mn-

(defvar +base-deck+
  '("0♠" "0♣" "0♥" "0♦" 
    "1♠" "1♣" "1♥" "1♦" 
    "2♠" "2♣" "2♥" "2♦" 
    "3♠" "3♣" "3♥" "3♦" 
    "4♠" "4♣" "4♥" "4♦" 
    "5♠" "5♣" "5♥" "5♦" 
    "6♠" "6♣" "6♥" "6♦" 
    "7♠" "7♣" "7♥" "7♦" 
    "8♠" "8♣" "8♥" "8♦" 
    "9♠" "9♣" "9♥" "9♦"))

(defun remove-nth (seq n)
  "Remove the n-th element from the sequence `seq', returns a new sequence with the desired result, the function doesnt modify `seq'"
  (unless (typep seq 'list) (error "Type error: seq must be a sequence."))
  (unless (typep n 'fixnum) (error "Type error: n must be a fixnum."))
  (remove-if #'identity seq :start n :count 1))

(defun strip-suit (card)
  (unless (typep card 'string) (error "Type error: card must be a string."))
  "Return the integer at the beginning of a card."
  (parse-integer (subseq card 0 1)))

(defun diff (x y)
  (unless (typep x 'fixnum) (error "Type error: x must be a fixnum."))
  (unless (typep y 'fixnum) (error "Type error: y must be a fixnum."))
  (abs (- x y)))

(defun display-cross (set)
  "Display 5 elements in Atlantean cross."
  (unless (typep set 'list) (error "Type error: set must be a list."))
  (format t "

       ~A

    ~A    ~A

       ~A

       ~A

"
	  (elt set 3)
	  (elt set 2)
	  (elt set 1)
	  (elt set 0)
	  (elt set 4)))

(defun shuffle (deck)
  "Shuffle a list."
  (unless (typep deck 'list) (error "Type error: deck must be a list."))
  (loop for i from (length deck) downto 2
	do (rotatef (elt deck (random i (make-random-state t)))
		    (elt deck (1- i))))
  deck)