;;; org-flymake.el --- Org support for flymake.el  -*- lexical-binding: t; -*-
;;
;; Copyright (C) 2018 Free Software Foundation, Inc.
;;
;; This file is a part of GNU Emcas.
;;
;; GNU Emacs 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.
;;
;; GNU Emacs 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 GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
;;
;;
;;; Commentary:
;; This file implements support for flymake.el in org mode buffers.
;; To enable it permanently in all org buffers, add this to your Emacs
;; configuration file:
;;
;; (add-hook 'org-mode-hook #'org-flymake-setup)
;;
;; Flymake supports multiple backends.  Currently we use `org-lint' only.

;;; Code:

(eval-when-compile
  (require 'cl-lib))
(require 'org-lint)
(require 'seq)

(defun org-flymake-org-lint-backend (report-fn &rest _args)
  "A Flymake backend for `org-lint'.
Calls REPORT-FN directly."
  (let* ((report (org-lint--generate-reports
		  (current-buffer) org-lint--checkers))
	 (report (mapcar
		  (lambda (c) (seq-into (nth 0 (cdr c)) 'list))
		  report)))
    (funcall report-fn
	     (cl-loop
	      for (line _trust description _checkers) in report
	      for (beg . end) = (flymake-diag-region (current-buffer) (string-to-number line))
	      collect
	      (flymake-make-diagnostic (current-buffer) beg end :note description)))
    report))

;;;###autoload
(defun org-flymake-setup ()
  "Add `org-flymake' to `flymake-diagnostic-functions'."
  (if (< emacs-major-version 26)
      (user-error "Org-flymake requires Emacs 26.1 or greater")
    (add-hook 'flymake-diagnostic-functions #'org-flymake-org-lint-backend nil t)
    (flymake-mode)))

(provide 'org-flymake)

;;; org-flymake.el ends here