;;; insert-separator.el
;;;
;;; Copyright (C) 1997, 1998, 2004, 2007, 2008 Thien-Thi Nguyen
;;;
;;; This file is part of ttn's personal elisp library, released under
;;; the terms of the GNU General Public License as published by the
;;; Free Software Foundation; either version 3, or (at your option) any
;;; later version.  There is NO WARRANTY.  See file COPYING for details.

;;; Description: Insert code separator comment in mode-specific ways.  Fancy.

(require 'cl)
(require 'yo)

;;;###autoload
(defun insert-separator ()
  "Inserts line of dashes ending using a mode-specific comment prefix.
Because we have MIPS to spare these days (hee hee), why not animate it?"
  (interactive)

  (let* ((str (case major-mode
                ((scheme-mode
                  lisp-mode
                  emacs-lisp-mode
                  inferior-lisp-mode
                  lisp-interaction-mode)        ";;;")
                ((c-mode
                  c++-mode)                     "//")
                ((texinfo-mode)                 "@c ")
                (t                              "")))
         (len (length str))

         ;; To make things interesting, choose a different way each time.
         ;; Register them here.

         (ways '[starfield
                 grow-from-left
                 instantly])

         (way (aref ways (random (length ways))))

         )

    ;; OK, now do it.  Take care of positioning first.

    (if (bolp)
        nil
      (forward-line 1)
      (beginning-of-line))

    ;; Based on the chosen way, put the thing in motion.

    (case way

     ('starfield                        ; starfield
      (do ((j 0 (1+ j)))
          ((= j 10))
        (let ((printme (starfield-string 78)))
          (insert printme)
          (sit-for 0.05)
          (delete-char (- (length printme)))))
      (insert (substring (concat str (make-string 78 ?-)) 0 78) "\n"))

     ('grow-from-left                   ; grow-from-left
      (while (< len 78)
        (setq str (concat str "-")
              len (1+ len))
        (insert str)
        (sit-for 0.01)
        (delete-char (- len)))
      (insert str "\n"))

     ('instantly
       (insert str (make-string (- 78 (length str)) ?-) "\n"))

     ;; Add new methods here.

     )))

(provide 'insert-separator)

;;; insert-separator.el ends here