;;; org-pretty.el --- Support for prettify-symbols-mode  -*- lexical-binding: t; -*-

;; Copyright (C) 2018 Free Software Foundation, Inc.
;;
;; Author: J. Alexander Branham <alex.branham at gmail dot com>
;; Maintainer: emacs-orgmode@gnu.org
;;
;; This file is part of GNU Emacs.
;;
;; 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 adds support for `prettify-symbols-mode' in Org buffers.
;; To use, call M-x org-prettify-mode or put
;;
;; (add-hook 'org-mode-hook #'org-prettify-mode)
;;
;; in your configuration file.

;;; Code:

(require 'org)

(defvar-local org-pretty-alist '(("*" . ?•))
  "An alist of symbols to prettify, see `prettify-symbols-alist'.
Whether the symbol actually gets prettified is controlled by
`org-pretty-compose-p', which see.")

(defun org-pretty-compose-p (start end match)
  "Return non-nil if the symbol between START and END is to be prettified.
MATCH is the string match.  See also
`prettify-symbols-compose-predicate'."
  (if (string= match "*")
      ;; Prettify asterisks in headings.
      (and (org-match-line org-outline-regexp-bol)
	   (< end (match-end 0)))
    ;; Else rely on the default function.
    (funcall #'prettify-symbols-default-compose-p start end match)))

;;;###autoload
(define-minor-mode org-pretty-mode
  "Set up `prettify-symbols-mode' in org buffers."
  :lighter nil
  :keymap nil
  (if org-pretty-mode
      ;; Turn on.
      (when (eq major-mode 'org-mode)
	(setq-local prettify-symbols-alist org-pretty-alist)
	(setq-local prettify-symbols-compose-predicate #'org-pretty-compose-p)
	(prettify-symbols-mode))
    ;; Turn off.
    (when (eq major-mode 'org-mode)
      (setq-local prettify-symbols-alist nil)
      (setq-local prettify-symbols-compose-predicate #'prettify-symbols-default-compose-p)
      (prettify-symbols-mode -1))))

(provide 'org-pretty)

;;; org-pretty.el ends here