;;; guile-fontconfig --- FFI bindings for FontConfig
;;; Copyright © 2021 Nicolò Balzarotti <nicolo@nixo.xyz>
;;;
;;; This file is part of guile-fontconfig.
;;;
;;; Guile-fontconfig is free software; you can redistribute it and/or
;;; modify it under the terms of the GNU Lesser General Public License
;;; as published by the Free Software Foundation; either version 3 of
;;; the License, or (at your option) any later version.
;;;
;;; Guile-fontconfig 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 Lesser General Public
;;; License along with guile-fontconfig.  If not, see
;;; <http://www.gnu.org/licenses/>.

;;; Commentary:
;;
;; Low-level FFI bindings.
;;
;;; Code:

(define-module (fontconfig bindings)
  #:use-module (fontconfig config)
  #:use-module (system foreign)
  #:export (fontconfig-func
            define-foreign

            fontconfig-pattern-create fontconfig-pattern-destroy
            fontconfig-object-set-destroy))

(define fontconfig-func
  (let ((lib (dynamic-link %libfontconfig)))
    (lambda (return-type function-name arg-types)
      "Return a procedure for the foreign function FUNCTION-NAME in
the FontConfig shared library.  That function must return a value of
RETURN-TYPE and accept arguments of ARG-TYPES."
      (pointer->procedure return-type
                          (dynamic-func function-name lib)
                          arg-types))))

(define-syntax-rule (define-foreign name return-type func-name arg-types)
  (define-public name
    (fontconfig-func return-type func-name arg-types)))


;;;
;;; Initialization
;;;

(define-foreign fontconfig-init-load-config-and-fonts
  '* "FcInitLoadConfigAndFonts" '())

(define-foreign fontconfig-finalize
  void "FcFini" '())


;;;
;;; Version
;;;

(define-foreign fontconfig-get-version
  int "FcGetVersion" '())


;;;
;;; Pattern
;;;

(define-foreign fontconfig-pattern-create
  '* "FcPatternCreate" '())

(define fontconfig-pattern-destroy
  (dynamic-func "FcPatternDestroy" (dynamic-link %libfontconfig)))

(define-foreign fontconfig-pattern-add-string
  int "FcPatternAddString" '(* * *))

(define-foreign fontconfig-pattern-add-double
  int "FcPatternAddDouble" `(* * ,double))

(define-foreign fontconfig-pattern-add-integer
  int "FcPatternAddInteger" `(* * ,int))

(define-foreign fontconfig-pattern-add-bool
  int "FcPatternAddBool" `(* * ,int))

(define-foreign fontconfig-name-unparse
  '* "FcNameUnparse" '(*))

(define-foreign fontconfig-pattern-format
  '* "FcPatternFormat" '(* *))

;; FcResult (FcPattern *p, const char *object, int id, FcValue *v);
(define-foreign fontconfig-pattern-get
  int "FcPatternGet" `(* * ,int *))

;;;
;;; Object Set
;;;
(define-foreign fontconfig-object-set-create
  '* "FcObjectSetCreate" '())

(define-foreign fontconfig-object-set-add
  int "FcObjectSetAdd" '(* *))

(define-foreign fontconfig-font-list
  '* "FcFontList" '(* * *))

(define fontconfig-object-set-destroy
  (dynamic-func "FcObjectSetDestroy" (dynamic-link %libfontconfig)))