Convert consecutive FSF copyright years to ranges.

[bpt/emacs.git] / lisp / mail / footnote.el

;;; footnote.el --- footnote support for message mode  -*- coding: iso-latin-1;-*-

;; Copyright (C) 1997, 2000-2011 Free Software Foundation, Inc.

;; Author: Steven L Baur <steve@xemacs.org>
;; Keywords: mail, news
;; Version: 0.19

;; 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 <http://www.gnu.org/licenses/>.

;;; Commentary:

;; This file provides footnote[1] support for message-mode in emacsen.
;; footnote-mode is implemented as a minor mode.

;; [1] Footnotes look something like this.  Along with some decorative
;; stuff.

;; TODO:
;; Reasonable Undo support.
;; more language styles.

;;; Code:

(eval-when-compile
  (require 'cl)
  (defvar filladapt-token-table))

(defgroup footnote nil
  "Support for footnotes in mail and news messages."
  :version "21.1"
  :group 'message)

(defcustom footnote-mode-line-string " FN"
  "String to display in modes section of the mode-line."
  :group 'footnote)

(defcustom footnote-mode-hook nil
  "Hook functions run when footnote-mode is activated."
  :type 'hook
  :group 'footnote)

(defcustom footnote-narrow-to-footnotes-when-editing nil
  "If non-nil, narrow to footnote text body while editing a footnote."
  :type 'boolean
  :group 'footnote)

(defcustom footnote-prompt-before-deletion t
  "If non-nil, prompt before deleting a footnote.
There is currently no way to undo deletions."
  :type 'boolean
  :group 'footnote)

(defcustom footnote-spaced-footnotes t
  "If non-nil, insert an empty line between footnotes.
Customizing this variable has no effect on buffers already
displaying footnotes."
  :type 'boolean
  :group 'footnote)

(defcustom footnote-use-message-mode t ; Nowhere used.
  "If non-nil, assume Footnoting will be done in `message-mode'."
  :type 'boolean
  :group 'footnote)

(defcustom footnote-body-tag-spacing 2
  "Number of spaces separating a footnote body tag and its text.
Customizing this variable has no effect on buffers already
displaying footnotes."
  :type 'integer
  :group 'footnote)

(defcustom footnote-prefix [(control ?c) ?!]
  "Prefix key to use for Footnote command in Footnote minor mode.
The value of this variable is checked as part of loading Footnote mode.
After that, changing the prefix key requires manipulating keymaps."
  ;; FIXME: the type should be a key-sequence, but it seems Custom
  ;; doesn't support that yet.
  ;; :type  'string
  )

;;; Interface variables that probably shouldn't be changed

(defcustom footnote-section-tag "Footnotes: "
  "Tag inserted at beginning of footnote section.
If you set this to the empty string, no tag is inserted and the
value of `footnote-section-tag-regexp' is ignored.  Customizing
this variable has no effect on buffers already displaying
footnotes."
  :type 'string
  :group 'footnote)

(defcustom footnote-section-tag-regexp "Footnotes\\(\\[.\\]\\)?: "
  "Regexp which indicates the start of a footnote section.
This variable is disregarded when `footnote-section-tag' is the
empty string.  Customizing this variable has no effect on buffers
already displaying footnotes."
  :type 'regexp
  :group 'footnote)

;; The following three should be consumed by footnote styles.
(defcustom footnote-start-tag "["
  "String used to denote start of numbered footnote.
Should not be set to the empty string.  Customizing this variable
has no effect on buffers already displaying footnotes."
  :type 'string
  :group 'footnote)

(defcustom footnote-end-tag "]"
  "String used to denote end of numbered footnote.
Should not be set to the empty string.  Customizing this variable
has no effect on buffers already displaying footnotes."
  :type 'string
  :group 'footnote)

(defvar footnote-signature-separator (if (boundp 'message-signature-separator)
					 message-signature-separator
				       "^-- $")
  "*String used to recognize .signatures.")

;;; Private variables

(defvar footnote-style-number nil
  "Footnote style represented as an index into footnote-style-alist.")
(make-variable-buffer-local 'footnote-style-number)

(defvar footnote-text-marker-alist nil
  "List of markers pointing to text of footnotes in message buffer.")
(make-variable-buffer-local 'footnote-text-marker-alist)

(defvar footnote-pointer-marker-alist nil
  "List of markers pointing to footnote pointers in message buffer.")
(make-variable-buffer-local 'footnote-pointer-marker-alist)

(defvar footnote-mouse-highlight 'highlight
  "Text property name to enable mouse over highlight.")

;;; Default styles
;;; NUMERIC
(defconst footnote-numeric-regexp "[0-9]+"
  "Regexp for digits.")

(defun Footnote-numeric (n)
  "Numeric footnote style.
Use Arabic numerals for footnoting."
  (int-to-string n))

;;; ENGLISH UPPER
(defconst footnote-english-upper "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
  "Upper case English alphabet.")

(defconst footnote-english-upper-regexp "[A-Z]+"
  "Regexp for upper case English alphabet.")

(defun Footnote-english-upper (n)
  "Upper case English footnoting.
Wrapping around the alphabet implies successive repetitions of letters."
  (let* ((ltr (mod (1- n) (length footnote-english-upper)))
	 (rep (/ (1- n) (length footnote-english-upper)))
	 (chr (char-to-string (aref footnote-english-upper ltr)))
	 rc)
    (while (>= rep 0)
      (setq rc (concat rc chr))
      (setq rep (1- rep)))
    rc))

;;; ENGLISH LOWER
(defconst footnote-english-lower "abcdefghijklmnopqrstuvwxyz"
  "Lower case English alphabet.")

(defconst footnote-english-lower-regexp "[a-z]+"
  "Regexp of lower case English alphabet.")

(defun Footnote-english-lower (n)
  "Lower case English footnoting.
Wrapping around the alphabet implies successive repetitions of letters."
  (let* ((ltr (mod (1- n) (length footnote-english-lower)))
	 (rep (/ (1- n) (length footnote-english-lower)))
	 (chr (char-to-string (aref footnote-english-lower ltr)))
	 rc)
    (while (>= rep 0)
      (setq rc (concat rc chr))
      (setq rep (1- rep)))
    rc))

;;; ROMAN LOWER
(defconst footnote-roman-lower-list
  '((1 . "i") (5 . "v") (10 . "x")
    (50 . "l") (100 . "c") (500 . "d") (1000 . "m"))
  "List of roman numerals with their values.")

(defconst footnote-roman-lower-regexp "[ivxlcdm]+"
  "Regexp of roman numerals.")

(defun Footnote-roman-lower (n)
  "Generic Roman number footnoting."
  (Footnote-roman-common n footnote-roman-lower-list))

;;; ROMAN UPPER
(defconst footnote-roman-upper-list
  '((1 . "I") (5 . "V") (10 . "X")
    (50 . "L") (100 . "C") (500 . "D") (1000 . "M"))
  "List of roman numerals with their values.")

(defconst footnote-roman-upper-regexp "[IVXLCDM]+"
  "Regexp of roman numerals.  Not complete")

(defun Footnote-roman-upper (n)
  "Generic Roman number footnoting."
  (Footnote-roman-common n footnote-roman-upper-list))

(defun Footnote-roman-common (n footnote-roman-list)
  "Lower case Roman footnoting."
  (let* ((our-list footnote-roman-list)
	 (rom-lngth (length our-list))
	 (rom-high 0)
	 (rom-low 0)
	 (rom-div -1)
	 (count-high 0)
	 (count-low 0))
    ;; find surrounding numbers
    (while (and (<= count-high (1- rom-lngth))
		(>= n (car (nth count-high our-list))))
      ;; (message "Checking %d" (car (nth count-high our-list)))
      (setq count-high (1+ count-high)))
    (setq rom-high count-high)
    (setq rom-low (1- count-high))
    ;; find the appropriate divisor (if it exists)
    (while (and (= rom-div -1)
		(< count-low rom-high))
      (when (or (> n (- (car (nth rom-high our-list))
			(/ (car (nth count-low our-list))
			   2)))
		(= n (- (car (nth rom-high our-list))
			(car (nth count-low our-list)))))
	(setq rom-div count-low))
      ;; (message "Checking %d and %d in div loop" rom-high count-low)
      (setq count-low (1+ count-low)))
    ;;(message "We now have high: %d, low: %d, div: %d, n: %d"
    ;;	       rom-high rom-low (if rom-div rom-div -1) n)
    (let ((rom-low-pair (nth rom-low our-list))
	  (rom-high-pair (nth rom-high our-list))
	  (rom-div-pair (if (not (= rom-div -1)) (nth rom-div our-list) nil)))
      ;; (message "pairs are: rom-low: %S, rom-high: %S, rom-div: %S"
      ;;	  rom-low-pair rom-high-pair rom-div-pair)
      (cond
       ((< n 0) (error "Footnote-roman-common called with n < 0"))
       ((= n 0) "")
       ((= n (car rom-low-pair)) (cdr rom-low-pair))
       ((= n (car rom-high-pair)) (cdr rom-high-pair))
       ((= (car rom-low-pair) (car rom-high-pair))
	(concat (cdr rom-low-pair)
		(Footnote-roman-common
		 (- n (car rom-low-pair))
		 footnote-roman-list)))
       ((>= rom-div 0) (concat (cdr rom-div-pair) (cdr rom-high-pair)
			       (Footnote-roman-common
				(- n (- (car rom-high-pair)
					(car rom-div-pair)))
				footnote-roman-list)))
       (t (concat (cdr rom-low-pair)
		  (Footnote-roman-common
		   (- n (car rom-low-pair))
		   footnote-roman-list)))))))

;; Latin-1