;;; mime-image.el --- mime-view filter to display images

;; Copyright (C) 1995,1996,1997,1998 MORIOKA Tomohiko
;; Copyright (C) 1996 Dan Rich

;; Author: MORIOKA Tomohiko <morioka@jaist.ac.jp>
;;         Dan Rich <drich@morpheus.corp.sgi.com>
;; Maintainer: MORIOKA Tomohiko <morioka@jaist.ac.jp>
;; Created: 1995/12/15
;;	Renamed: 1997/2/21 from tm-image.el

;; Keywords: image, picture, X-Face, MIME, multimedia, mail, news

;; This file is part of SEMI (Showy Emacs MIME Interfaces).

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

;;; Commentary:
;;	If you use this program with MULE, please install
;;	etl8x16-bitmap.bdf font included in tl package.

;;; Code:

(require 'mime-view)
(require 'alist)

(cond ((featurep 'xemacs)
       (require 'images)
       
       (defun-maybe image-inline-p (format)
	 (or (memq format image-native-formats)
	     (find-if (function
		       (lambda (native)
			 (image-converter-chain format native)
			 ))
		      image-native-formats)
	     ))
       
       (image-register-netpbm-utilities)
       (image-register-converter 'pic 'ppm "pictoppm")
       (image-register-converter 'mag 'ppm "magtoppm")
       
       (defun bitmap-insert-xbm-file (file)
	 (let ((gl (make-glyph (list (cons 'x file))))
	       (e (make-extent (point) (point)))
	       )
	   (set-extent-end-glyph e gl)
	   ))
       
       ;;
       ;; X-Face
       ;;
       (autoload 'highlight-headers "highlight-headers")
       
       (defun mime-preview-x-face-function-use-highlight-headers ()
	 (highlight-headers (point-min) (re-search-forward "^$" nil t) t)
	 )
       
       (add-hook 'mime-display-header-hook
		 'mime-preview-x-face-function-use-highlight-headers)
       
       )
      ((featurep 'mule)
       ;; for MULE 2.* or mule merged EMACS
       (require 'x-face-mule)

       (defvar image-native-formats '(xbm))
       
       (defun-maybe image-inline-p (format)
	 (memq format image-native-formats)
	 )
       
       (defun-maybe image-normalize (format data)
	 (and (eq format 'xbm)
	      (vector 'xbm ':data data)
	      ))
       
       ;;
       ;; X-Face
       ;;
       (if (exec-installed-p uncompface-program exec-path)
	   (add-hook 'mime-display-header-hook
		     'x-face-decode-message-header)
	 )
       ))

(or (fboundp 'image-invalid-glyph-p)
    (defsubst image-invalid-glyph-p (glyph)
      (or (null (aref glyph 0))
	  (null (aref glyph 2))
	  (equal (aref glyph 2) "")
	  ))
    )

(mapcar (function
	 (lambda (rule)
	   (let ((type    (car rule))
		 (subtype (nth 1 rule))
		 (format  (nth 2 rule)))
	     (if (image-inline-p format)
		 (ctree-set-calist-strictly
		  'mime-preview-condition
		  (list (cons 'type type)(cons 'subtype subtype)
			'(body . visible)
			(cons 'body-presentation-method #'mime-display-image)
			(cons 'image-format format))
		  )))))
	'((image jpeg		jpeg)
	  (image gif		gif)
	  (image tiff		tiff)
	  (image x-tiff		tiff)
	  (image xbm		xbm)
	  (image x-xbm		xbm)
	  (image x-xpixmap	xpm)
	  (image x-pic		pic)
	  (image x-mag		mag)
	  (image png		png)
	  ))


;;; @ content filter for images
;;;
;;    (for XEmacs 19.12 or later)

(defun mime-display-image (entity situation)
  (message "Decoding image...")
  (let ((gl (image-normalize (cdr (assq 'image-format situation))
			     (mime-entity-content entity))))
    (cond ((image-invalid-glyph-p gl)
	   (setq gl nil)
	   (message "Invalid glyph!")
	   )
	  ((eq (aref gl 0) 'xbm)
	   (let ((xbm-file
		  (make-temp-name
		   (expand-file-name "tm" temporary-file-directory))))
	     (with-temp-buffer
	       (insert (aref gl 2))
	       (write-region (point-min)(point-max) xbm-file)
	       )
	     (message "Decoding image...")
	     (bitmap-insert-xbm-file xbm-file)
	     (delete-file xbm-file)
	     )
	   (message "Decoding image... done")
	   )
	  (t
	   (setq gl (make-glyph gl))
	   (let ((e (make-extent (point) (point))))
	     (set-extent-end-glyph e gl)
	     )
	   (message "Decoding image... done")
	   ))
    )
  (insert "\n")
  )


;;; @ end
;;;

(provide 'mime-image)

;;; mime-image.el ends here