;; pick-a-string.el -- Pick a random string from a file.
;; -*- Mode: Emacs-Lisp -*-
;; Copyright(C) 2003 Daisuke Kakura <info@kakura.jp> "2003-11-04 Tue 02:11:02 CCT"

;; This program 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 2, or (at your option)
;; any later version.
;;
;; This program 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 this program; if not, you can either send email to this
;; program's maintainer or write to: The Free Software Foundation,
;; Inc.; 59 Temple Place, Suite 330; Boston, MA 02111-1307, USA.

;; HISTORY:
;;
;; 2003-11-01  v0.1  Daisuke Kakura: created.

;; INSTALL:
;;
;;    (require 'pick-a-string)

;; HOW TO USE:
;;
;; `pick-a-string' randomly picks a string from a file and displays it
;; to mini-buffer. The each data string should be terminated by
;; `pick-a-string-terminator'.
;;
;; `pick-a-string-and-insert' inserts the string where the cursor is.
;;
;; `pick-a-string-and-insert-last-one' inserts the last picked string.


(defvar pick-a-string-file (expand-file-name "~/.pick-a-string")
	"Name of a file containing strings terminated with `pick-a-string-terminater'.")

(defvar pick-a-string-terminator "\n%\n"
	"Terminator character or string between data strings in `pick-a-string-file'.")

(defvar pick-a-string-last-one nil
	"The last picked string.")


(defun pick-a-string (&optional silent)
	"Randomly pick a string from a file and display it to mini-buffer.
 If &optional argument t was given, nothing appears in mini-buffer."
	(interactive)
	(let ((buf (find-file-noselect pick-a-string-file))
			(num-strings 0)
			random-num
			beg end)
		(save-excursion
		   ;; count delimiters.
			(set-buffer buf)
			(goto-char (point-min))
			(while (search-forward pick-a-string-terminator nil t)
				(setq num-strings (1+ num-strings)))
			;; generate a random number.
			(random t)
			(setq random-num (random num-strings))
			;; then pick it up.
			(goto-char (point-min))
			(search-forward pick-a-string-terminator nil nil random-num)
			(setq beg (point))
			(search-forward pick-a-string-terminator)
			(setq end (match-beginning 0))
			(goto-char beg)
			(setq pick-a-string-last-one (buffer-substring-no-properties beg end))
			;; done.
			(kill-buffer buf)))
	(if silent
		pick-a-string-last-one
	 (message pick-a-string-last-one)))

(defun pick-a-string-and-insert ()
	"Insert a random string at current point."
	(interactive)
	(pick-a-string)
	(insert pick-a-string-last-one))

(defun pick-a-string-and-insert-last-one ()
	"Insert the last picked string at current point."
	(interactive)
	(insert pick-a-string-last-one))

(provide 'pick-a-string)

;;; pick-a-string.el ends here.