;;; Lisp Game Jam 2018
;;; Copyright © 2018 David Thompson <davet@gnu.org>
;;;
;;; This program 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.
;;;
;;; This program 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 this program.  If not, see
;;; <http://www.gnu.org/licenses/>.

(define-module (engine scene)
  #:use-module (chickadee audio)
  #:use-module (engine node-2d)
  #:use-module (oop goops)
  #:export (<scene>
            background-music
            background-music-volume
            background-music-loop?))

(define-class <scene> (<node-2d>)
  (background-music #:accessor background-music #:init-form #f
                    #:init-keyword #:music)
  (background-music-volume #:accessor background-music-volume #:init-form 1.0
                           #:init-keyword #:music-volume)
  (background-music-loop? #:accessor background-music-loop? #:init-form #t
                          #:init-keyword #:music-loop?))

(define-method (on-enter (scene <scene>))
  (if (music? (background-music scene))
      (begin
        (set-music-volume! (background-music-volume scene))
        (play-music (background-music scene)
                    #:loop? (background-music-loop? scene)))
      (stop-music)))

(define-method (on-exit (scene <scene>))
  (stop-music))