;;; Mudsync --- Live hackable MUD
;;; Copyright © 2016 Christopher Allan Webber <cwebber@dustycloud.org>
;;;
;;; This file is part of Mudsync.
;;;
;;; Mudsync is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or
;;; (at your option) any later version.
;;;
;;; Mudsync is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
;;; General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with Mudsync.  If not, see <http://www.gnu.org/licenses/>.

(define-module (mudsync room)
  #:use-module (mudsync gameobj)
  #:use-module (8sync systems actors)
  #:use-module (8sync agenda)
  #:use-module (oop goops)
  #:export (<room>
            <exit>))

;;; Rooms
;;; =====

(define-class <exit> ()
  ;; Used for wiring
  (to-symbol #:accessor exit-to-symbol
             #:init-keyword #:to-symbol)
  ;; The actual address we use
  (to-address #:accessor exit-to-address
              #:init-keyword #:address)
  ;; Name of the room (@@: Should this be names?)
  (name #:accessor exit-name
        #:init-keyword #:name)
  (desc #:accessor exit-desc
               #:init-keyword #:desc)

  ;; *Note*: These two methods have an extra layer of indirection, but
  ;;   it's for a good reason.
  (visible-check #:init-value (const #t)
                 #:init-keyword #:visible-check)
  ;; By default all exits can be traversed
  (traverse-check #:init-value (const #t)
                  #:init-keyword #:traverse-check))

(define* (exit-can-traverse? exit actor
                             #:optional (target-actor (actor-id actor)))
  ((slot-ref exit 'traverse-check) exit actor target-actor))

(define* (exit-is-visible? exit actor
                           #:optional (target-actor (actor-id actor)))
  ((slot-ref exit 'traverse-check) exit actor target-actor))


;; Kind of a useful utility, maybe?
(define (simple-slot-getter slot)
  (lambda (actor message)
    (reply-message actor message
                   #:val (slot-ref actor slot))))

(define always (const #t))

;; TODO: remove hack
(define full-command list)

;; TODO: fill these in
(define cmatch-just-verb #f)
(define cmatch-direct-verb #f)
(define cmatch-direct-obj #f)

(define %room-contain-commands
  (list
   (full-command "look" cmatch-just-verb always 'look-room)
   (full-command "look" cmatch-direct-obj always 'look-member)
   (full-command "go" cmatch-just-verb always 'go-where)
   (full-command "go" cmatch-direct-obj always 'go-exit)))

;; TODO: Subclass from container?
(define-class <room> (<gameobj>)
  (desc #:init-value ""
        #:init-keyword #:desc)
  ;; TODO: Switch this to be loc based
  ;; Uses a hash table like a set (values ignored)
  (occupants #:init-thunk make-hash-table)
  ;; A list of <exit>
  (exits #:init-value '()
         #:getter room-exits)
  ;; @@: Maybe eventually <room> will inherit from some more general
  ;;  game object class

  (contain-commands
   #:init-value %room-contain-commands)

  (message-handler
   #:allocation #:each-subclass
   #:init-value
   (make-action-dispatch
    ;; desc == description
    (get-desc
     (simple-slot-getter 'desc))
    (get-name
     (simple-slot-getter 'name))
    ((register-occupant! actor message who)
     "Register an actor as being a occupant of this room"
     (hash-set! (slot-ref actor 'occupants) who #t))
    ((evict-occupant! actor message who)
     "De-register an occupant removed from the room"
     (hash-remove! (slot-ref actor 'occupants) who))
    (wire-exits! (wrap-apply room-wire-exits!)))))

(define (room-wire-exits! room message)
  "Actually hook up the rooms' exit addresses to the rooms they
claim to point to."
  (for-each
   (lambda (exit)
     (define new-exit
       (<-wait room (gameobj-gm room) 'lookup-room
               #:symbol (exit-to-symbol exit)))

     (set! (exit-to-address exit) new-exit))

   (room-exits room)))