;;;
;;; Atlantis is a framework for creating multi-user dungeon worlds.
;;; This is the Common Lisp implementation.
;;;
;;; This file contains all the various kinds of in-game objects like
;;; places, monsters, NPCs, items...
;;;
;;; Licensed under the terms of the MIT license.
;;; author: Daniel Vedder
;;; date: 15/05/2015
;;;

(defstruct place
	(name "")
	(description "")
	;; Missing 's' in the following list names due to parsing issues
	(neighbour NIL)
	(player NIL)
	(item NIL)
	(monster NIL)
	(npc NIL))

;;; WORK IN PROGRESS >>>

(defstruct npc
	(name "")
	(description "")
	(says "")
	(sells NIL))

(defstruct monster
	(name "")
	(description "")
	(strength 0)
	(dexterity 0)
	(aggression 0)
	(weapon "")
	(armour-class 0))

(defstruct item
	(name "")
	(description "")
	(cost 0)
	(weapon "no")
	(function NIL))

(defstruct weapon
	(name "")
	(description "")
	(ranged NIL)
	(damage 0))


(defun set-object-attribute (game-object property value)
	"Set the attribute 'property' of 'game-object' to 'value'"
	;; Here follows Lisp magic :D      (that took ages to get right...)
	;; [And half the magic is gone after being outsourced to build-symbol :-(]
	;; I'm not sure how elegant it is to call (eval) explicitly, but in this
	;; case I couldn't avoid it - I needed a mix between a macro and a function
	(let ((command (build-symbol (type-of game-object) "-" property)))
		;; TODO This following section is rather ugly...
		(eval `(if (or (null (,command ,game-object))
					   (listp (,command ,game-object)))
				   (setf (,command ,game-object)
					   (append (,command ,game-object) '(,value)))
				   (setf (,command ,game-object) ,value)))))

(defun remove-object-attribute (game-object property value)
	"Remove 'value' from the attribute 'property' in 'game-object'"
	;; Same comment applies as above
	(let ((command (build-symbol (type-of game-object) "-" property)))
		(eval `(if (listp (,command ,game-object))
				   ;; FIXME This is going to give problems with multiple values
				   ;; (but will that scenario ever take place?)
				   (setf (,command ,game-object)
					   (remove-if #'(lambda (x) (equalp x ,value))
						   (,command ,game-object)))
				   (setf (,command ,game-object) NIL)))))

;; XXX This function is probably superfluous, as all place objects are stored
;; in world, with only their names recorded in the place
(let ((list-function (make-list-function 'place NIL)))
	(defun list-place-objects (object-type place)
		"Get a list of the names of all the place's objects of this type."
		(funcall list-function object-type place)))