;;; -*- lexical-binding: t -*-
;;
;; this file:
;;   https://dataswamp.org/~incal/emacs-init/fill-incal.el

(require 'message)

(setq sentence-end-double-space nil)

(setq fill-nobreak-predicate '(fill-single-char-nobreak-p
                               fill-single-word-nobreak-p) )

(let ((fill-col 62))
  (setq-default fill-column fill-col)
  (setq message-fill-column fill-col) )

;; region

(defun fill-down (beg end &optional justify)
  "Fill the current paragraph from the current line down.
\nWith mark active, act upon the region instead.
\nWith \\[universal-argument], remove full justification."
  (interactive
   (if (use-region-p)
       (list (region-beginning) (region-end) current-prefix-arg)
     (list (line-beginning-position)
           (save-excursion
             (forward-paragraph)
             (point) )
           current-prefix-arg) ))
  (if (and justify (equal justify '(4))) ;    C-u -> unjustify
      (canonically-space-region beg end)
    (fill-region beg end) ))             ; no C-u -> fill

(defun unfill-region (beg end)
  "Unfill the region, joining text paragraphs into a single line.
\nhttp://emacswiki.org/emacs/unfillregion"
  (interactive "*r")
  (let ((fill-column (point-max)))
    (fill-region beg end) ))

;; buffer

(defun fill-buffer ()
  "Fill all paragraphs in the buffer."
  (interactive)
  (fill-region (point-min) (point-max)) )

(defun unfill-buffer ()
  "Unfill all paragraphs in the buffer."
  (interactive)
  (unfill-region (point-min) (point-max)) )

(provide 'fill-incal)