;;; mcs-ltn1.el --- MIME charset implementation for Emacs 19
;;;                 and XEmacs without MULE

;; Copyright (C) 1995,1996,1997,1998,2000 Free Software Foundation, Inc.

;; Author: MORIOKA Tomohiko <tomo@m17n.org>
;; Keywords: emulation, compatibility, Mule

;; This file is part of APEL (A Portable Emacs Library).

;; 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 GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
;; Boston, MA 02111-1307, USA.

;;; Code:

(defvar charsets-mime-charset-alist
  '(((ascii) . us-ascii)))

(defvar default-mime-charset 'iso-8859-1)

(defsubst lbt-to-string (lbt)
  (cdr (assq lbt '((nil . nil)
		   (CRLF . "\r\n")
		   (CR . "\r")
		   (dos . "\r\n")
		   (mac . "\r"))))
  )

(defun mime-charset-to-coding-system (charset &optional lbt)
  (if (stringp charset)
      (setq charset (intern (downcase charset))))
  (if (memq charset (list 'us-ascii default-mime-charset))
      charset))

(defalias 'mime-charset-p 'mime-charset-to-coding-system)

(defun detect-mime-charset-region (start end)
  "Return MIME charset for region between START and END."
  (if (save-excursion
	(goto-char start)
	(re-search-forward "[\200-\377]" end t))
      default-mime-charset
    'us-ascii))

(defun encode-mime-charset-region (start end charset &optional lbt)
  "Encode the text between START and END as MIME CHARSET."
  (let ((newline (lbt-to-string lbt)))
    (if newline
	(save-excursion
	  (save-restriction
	    (narrow-to-region start end)
	    (goto-char (point-min))
	    (while (search-forward "\n" nil t)
	      (replace-match newline))
	    )))
      ))

(defun decode-mime-charset-region (start end charset &optional lbt)
  "Decode the text between START and END as MIME CHARSET."
  (let ((newline (lbt-to-string lbt)))
    (if newline
	(save-excursion
	  (save-restriction
	    (narrow-to-region start end)
	    (goto-char (point-min))
	    (while (search-forward newline nil t)
	      (replace-match "\n"))
	    )))
      ))

(defun encode-mime-charset-string (string charset &optional lbt)
  "Encode the STRING as MIME CHARSET."
  (if lbt
      (with-temp-buffer
	(insert string)
	(encode-mime-charset-region (point-min)(point-max) charset lbt)
	(buffer-string))
    string))

(defun decode-mime-charset-string (string charset &optional lbt)
  "Decode the STRING as MIME CHARSET."
  (if lbt
      (with-temp-buffer
	(insert string)
	(decode-mime-charset-region (point-min)(point-max) charset lbt)
	(buffer-string))
    string))

(defalias 'write-region-as-mime-charset 'write-region)


;;; @ end
;;;

(require 'product)
(product-provide (provide 'mcs-ltn1) (require 'apel-ver))

;;; mcs-ltn1.el ends here
