;;; Catbird Game Engine
;;; Copyright © 2023 David Thompson <davet@gnu.org>
;;;
;;; Catbird 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.
;;;
;;; Catbird 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 Catbird.  If not, see <http://www.gnu.org/licenses/>.

;;; Commentary:
;;
;; Generic math methods.
;;
;;; Code:
(define-module (catbird math)
  #:use-module (chickadee math matrix)
  #:use-module (chickadee math vector)
  #:use-module (oop goops)
  #:export (<vec2>
            <vec3>
            <matrix3>
            <matrix4>
            vec))

(define <vec2> (class-of (vec2 0.0 0.0)))
(define <vec3> (class-of (vec3 0.0 0.0 0.0)))
(define <matrix3> (class-of (make-identity-matrix3)))
(define <matrix4> (class-of (make-identity-matrix4)))

(define-method (vec (x <number>) (y <number>))
  (vec2 x y))

(define-method (vec (x <number>) (y <number>) (z <number>))
  (vec3 x y z))

(define-method (vec (v <vec2>) (z <number>))
  (vec3 (vec2-x v) (vec2-y v) z))

(define-method (vec (x <number>) (v <vec2>))
  (vec3 x (vec2-x v) (vec2-y v)))

(define-method (+ (a <vec2>) (b <vec2>))
  (vec2+ a b))

(define-method (+ (a <vec2>) (b <number>))
  (vec2+ a b))

(define-method (+ (a <number>) (b <vec2>))
  (vec2+ b a))

(define-method (+ (a <vec3>) (b <vec3>))
  (vec3+ a b))

(define-method (+ (a <vec3>) (b <number>))
  (vec3+ a b))

(define-method (+ (a <number>) (b <vec3>))
  (vec3+ b a))

(define-method (- (a <vec2>) (b <vec2>))
  (vec2- a b))

(define-method (- (a <vec2>) (b <number>))
  (vec2- a b))

(define-method (- (a <vec3>) (b <vec3>))
  (vec3- a b))

(define-method (- (a <vec3>) (b <number>))
  (vec3- a b))

(define-method (* (a <vec2>) (b <vec2>))
  (vec2* a b))

(define-method (* (a <vec2>) (b <number>))
  (vec2* a b))

(define-method (* (a <number>) (b <vec2>))
  (vec2* b a))

(define-method (* (a <vec3>) (b <vec3>))
  (vec3* a b))

(define-method (* (a <vec3>) (b <number>))
  (vec3* a b))

(define-method (* (a <number>) (b <vec3>))
  (vec3* b a))

(define-method (* (a <matrix3>) (b <matrix3>))
  (matrix3* a b))

(define-method (* (a <matrix4>) (b <matrix4>))
  (matrix4* a b))

(define-method (/ (a <vec2>) (b <vec2>))
  (vec2* a (vec2 (/ 1.0 (vec2-x b))
                 (/ 1.0 (vec2-y b)))))

(define-method (/ (a <vec2>) (b <number>))
  (vec2* a (/ 1.0 b)))

(define-method (/ (a <number>) (b <vec2>))
  (vec2* (vec2 (/ 1.0 (vec2-x b))
               (/ 1.0 (vec2-y b)))
         b))

(define-method (/ (a <vec3>) (b <vec3>))
  (vec3* a (vec3 (/ 1.0 (vec3-x b))
                 (/ 1.0 (vec3-y b))
                 (/ 1.0 (vec3-z b)))))

(define-method (/ (a <vec3>) (b <number>))
  (vec3* a (/ 1.0 b)))

(define-method (/ (a <number>) (b <vec3>))
  (vec3* (vec3 (/ 1.0 (vec3-x b))
               (/ 1.0 (vec3-y b))
               (/ 1.0 (vec3-z b)))
         b))