;;; mm-uu.el -- Return uu stuffs as mm handles
;; Copyright (c) 1998, 1999, 2000 Free Software Foundation, Inc.

;; Author: Shenghuo Zhu <zsh@cs.rochester.edu>
;; Keywords: postscript uudecode binhex shar forward news

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

;;; Commentary:


;;; Code:

(eval-when-compile (require 'cl))
(require 'mail-parse)
(require 'nnheader)
(require 'mm-decode)
(require 'mailcap)

(eval-and-compile
  (autoload 'binhex-decode-region "binhex")
  (autoload 'binhex-decode-region-external "binhex")
  (autoload 'uudecode-decode-region "uudecode")
  (autoload 'uudecode-decode-region-external "uudecode"))

(defun mm-uu-copy-to-buffer (from to)
  "Copy the contents of the current buffer to a fresh buffer."
  (save-excursion
    (let ((obuf (current-buffer)))
      (set-buffer (generate-new-buffer " *mm-uu*"))
      (insert-buffer-substring obuf from to)
      (current-buffer))))

;;; postscript

(defconst mm-uu-postscript-begin-line "^%!PS-")
(defconst mm-uu-postscript-end-line "^%%EOF$")

(defconst mm-uu-uu-begin-line "^begin[ \t]+[0-7][0-7][0-7][ \t]+")
(defconst mm-uu-uu-end-line "^end[ \t]*$")

(defcustom mm-uu-decode-function 'uudecode-decode-region
  "*Function to uudecode.
Internal function is done in elisp by default, therefore decoding may
appear to be horribly slow . You can make Gnus use the external Unix
decoder, such as uudecode."
  :type '(choice (item :tag "internal" uudecode-decode-region)
		 (item :tag "external" uudecode-decode-region-external))
  :group 'gnus-article-mime) 

(defconst mm-uu-binhex-begin-line
  "^:...............................................................$")
(defconst mm-uu-binhex-end-line ":$")

(defcustom mm-uu-binhex-decode-function 'binhex-decode-region
  "*Function to binhex decode.
Internal function is done in elisp by default, therefore decoding may
appear to be horribly slow . You can make Gnus use the external Unix
decoder, such as hexbin."
  :type '(choice (item :tag "internal" binhex-decode-region)
		 (item :tag "external" binhex-decode-region-external))
  :group 'gnus-article-mime) 

(defconst mm-uu-shar-begin-line "^#! */bin/sh")
(defconst mm-uu-shar-end-line "^exit 0\\|^$")

;;; Thanks to Edward J. Sabol <sabol@alderaan.gsfc.nasa.gov> and 
;;; Peter von der Ah\'e <pahe@daimi.au.dk>
(defconst mm-uu-forward-begin-line "^-+ \\(Start of \\)?Forwarded message")
(defconst mm-uu-forward-end-line "^-+ End \\(of \\)?forwarded message")

(defvar mm-uu-begin-line nil)

(defconst mm-uu-identifier-alist
  '((?% . postscript) (?b . uu) (?: . binhex) (?# . shar)
    (?- . forward)))

(defvar mm-dissect-disposition "inline"
  "The default disposition of uu parts.
This can be either \"inline\" or \"attachment\".")

(defun mm-uu-configure-p  (key val)
  (member (cons key val) mm-uu-configure-list))

(defun mm-uu-configure (&optional symbol value)
  (if symbol (set-default symbol value))
  (setq mm-uu-begin-line nil)
  (mapcar '(lambda (type)
	     (if (mm-uu-configure-p type 'disabled) 
		 nil
	       (setq mm-uu-begin-line
		     (concat mm-uu-begin-line
			     (if mm-uu-begin-line "\\|")
			     (symbol-value
			      (intern (concat "mm-uu-" (symbol-name type)
					      "-begin-line")))))))
	  '(uu postscript binhex shar forward)))

(defcustom mm-uu-configure-list nil
  "A list of mm-uu configuration.
To disable dissecting shar codes, for instance, add
`(shar . disabled)' to this list."
  :type '(repeat (cons 
		  (choice (item postscript)
			  (item uu) 
			  (item binhex)
			  (item shar)
			  (item forward))
		  (choice (item disabled))))
  :group 'gnus-article-mime
  :set 'mm-uu-configure) 

(mm-uu-configure)

;;;### autoload

(defun mm-uu-dissect ()
  "Dissect the current buffer and return a list of uu handles."
  (let (text-start start-char end-char
		   type file-name end-line result text-plain-type 
		   start-char-1 end-char-1
		   (case-fold-search t))
    (save-excursion
      (save-restriction
	(mail-narrow-to-head)
	(goto-char (point-max)))
      (forward-line)
      ;;; gnus-decoded is a fake charset, which means no further
      ;;; decoding.
      (setq text-start (point)
	    text-plain-type '("text/plain"  (charset . gnus-decoded)))
      (while (re-search-forward mm-uu-begin-line nil t)
	(setq start-char (match-beginning 0))
	(setq type (cdr (assq (aref (match-string 0) 0)
			      mm-uu-identifier-alist)))
	(setq file-name
	      (if (and (eq type 'uu)
		       (looking-at "\\(.+\\)$"))
		  (and (match-string 1)
		       (let ((nnheader-file-name-translation-alist
			      '((?/ . ?,) (? . ?_) (?* . ?_) (?$ . ?_))))
			 (nnheader-translate-file-chars (match-string 1))))))
	(forward-line);; in case of failure
	(setq start-char-1 (point))
	(setq end-line (symbol-value
			(intern (concat "mm-uu-" (symbol-name type)
					"-end-line"))))
	(when (and (re-search-forward end-line nil t)
		   (not (eq (match-beginning 0) (match-end 0))))
	  (setq end-char-1 (match-beginning 0))
	  (forward-line)
	  (setq end-char (point))
	  (when (cond 
		 ((eq type 'binhex)
		  (setq file-name
			(ignore-errors
			  (binhex-decode-region start-char end-char t))))
		 ((eq type 'forward)
		  (save-excursion
		    (goto-char start-char-1)
		    (looking-at "[\r\n]*[a-zA-Z][a-zA-Z0-9-]*:")))
		 (t t))
	    (if (> start-char text-start)
		(push
		 (mm-make-handle (mm-uu-copy-to-buffer text-start start-char)
				 text-plain-type)
		 result))
	    (push
	     (cond
	      ((eq type 'postscript)
	       (mm-make-handle (mm-uu-copy-to-buffer start-char end-char)
			       '("application/postscript")))
	      ((eq type 'forward)
	       (mm-make-handle (mm-uu-copy-to-buffer start-char-1 end-char-1)
			       '("message/rfc822" (charset . gnus-decoded))))
	      ((eq type 'uu)
	       (mm-make-handle (mm-uu-copy-to-buffer start-char end-char)
			       (list (or (and file-name
					      (string-match "\\.[^\\.]+$"
							    file-name)
					      (mailcap-extension-to-mime
					       (match-string 0 file-name)))
					 "application/octet-stream"))
			       'x-uuencode nil
			       (if (and file-name (not (equal file-name "")))
				   (list mm-dissect-disposition
					 (cons 'filename file-name)))))
	      ((eq type 'binhex)
	       (mm-make-handle (mm-uu-copy-to-buffer start-char end-char)
			       (list (or (and file-name
					      (string-match "\\.[^\\.]+$" file-name)
					      (mailcap-extension-to-mime
					       (match-string 0 file-name)))
					 "application/octet-stream"))
			       'x-binhex nil
			       (if (and file-name (not (equal file-name "")))
				   (list mm-dissect-disposition
					 (cons 'filename file-name)))))
	      ((eq type 'shar)
	       (mm-make-handle (mm-uu-copy-to-buffer start-char end-char)
			       '("application/x-shar"))))
	     result)
	    (setq text-start end-char))))
      (when result
	(if (> (point-max) (1+ text-start))
	    (push
	     (mm-make-handle (mm-uu-copy-to-buffer text-start (point-max))
			     text-plain-type)
	     result))
	(setq result (cons "multipart/mixed" (nreverse result))))
      result)))

;;;### autoload
(defun mm-uu-test ()
  "Check whether the current buffer contains uu stuffs."
  (save-excursion
    (goto-char (point-min))
    (let (type end-line result
	       (case-fold-search t))
      (while (and mm-uu-begin-line
		  (not result) (re-search-forward mm-uu-begin-line nil t))
	(forward-line)
	(setq type (cdr (assq (aref (match-string 0) 0)
			      mm-uu-identifier-alist)))
	(setq end-line (symbol-value
			(intern (concat "mm-uu-" (symbol-name type)
					"-end-line"))))
	(if (and (re-search-forward end-line nil t)
		 (not (eq (match-beginning 0) (match-end 0))))
	    (setq result t)))
      result)))

(provide 'mm-uu)

;;; mm-uu.el ends here