* WIP: show image attachment inline (mu4e-view-show-images)

emacs/mu4e-headers.el

@@ -897,7 +897,7 @@ current window. "
       (erase-buffer)
       (insert (propertize "Waiting for message..."
 		'face 'mu4e-system-face 'intangible t))
-      (mu4e~proc-view docid))))
+      (mu4e~proc-view docid mu4e-view-show-images))))
 
 (defun mu4e~headers-kill-buffer-and-window ()
   "Quit the message view and return to the main view."

emacs/mu4e-proc.el

@@ -421,12 +421,15 @@ mean:
 response."
   (mu4e~proc-send-command "ping"))
 
-(defun mu4e~proc-view (docid-or-msgid)
+(defun mu4e~proc-view (docid-or-msgid &optional images)
   "Get one particular message based on its DOCID-OR-MSGID (keyword
-argument). The result will be delivered to the function registered
+argument). Optionally, if IMAGES is non-nil, backend will any
-as `mu4e-message-func'."
+images attached to the message, and return them as temp files.  The
-  (mu4e~proc-send-command "view %s"
+result will be delivered to the function registered as
-    (mu4e--docid-msgid-param docid-or-msgid)))
+`mu4e-message-func'."
+  (mu4e~proc-send-command "view %s extract-images:%s"
+    (mu4e--docid-msgid-param docid-or-msgid)
+    (if images "true" "false")))
 
 (provide 'mu4e-proc)
 

emacs/mu4e-utils.el

@@ -720,6 +720,27 @@ mu4e logs some of its internal workings to a log-buffer. See
       (error "No debug log available"))
     (switch-to-buffer buf)))
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(defvar mu4e-imagemagick-identify "identify"
+  "Name/path of the Imagemagick 'identify' program.")
+
+(defun mu4e-display-image (imgpath &optional maxwidth)
+  "Display image IMG at point; optionally specify
+MAXWIDTH. Function tries to use imagemagick if available; otherwise
+MAXWIDTH is ignored."
+  (when
+    (let*
+      ((identify (and maxwidth (executable-find mu4e-imagemagick-identify)))
+	(props (and identify (shell-command-to-string
+			       (format "%s -format '%%w' %s"
+				 identify (shell-quote-argument imgpath)))))
+	(width (and props (string-to-number props)))
+	(img
+	      (if (> (or width 0) (or maxwidth 0))
+		(create-image imgpath 'imagemagick nil :width maxwidth)
+		(create-image imgpath 'imagemagick))))
+      (newline)
+      (insert-image img imgpath nil t))))
 
 
 (provide 'mu4e-utils)

emacs/mu4e-view.el

@@ -86,6 +86,15 @@ display with `mu4e-view-toggle-hide-cited (default keybinding:
 <w>)."
   :group 'mu4e-view)
 
+(defcustom mu4e-view-show-images nil
+  "Whether to automatically display attached images in the message
+buffer."
+  :group 'mu4e-view)
+
+(defcustom mu4e-view-image-max-width 800
+  "The maximum width for images to display; this is only effective
+  if you're using an emacs with Imagemagick support."
+  :group 'mu4e-view)
 
 (defvar mu4e-view-actions
   '( ("capture message" ?c mu4e-action-capture-message)
@@ -134,11 +143,10 @@ where:
 
 
 
-
 (defun mu4e-view-message-with-msgid (msgid)
   "View message with MSGID. This is meant for external programs
 wanting to show specific messages - for example, `mu4e-org'."
-  (mu4e~proc-view msgid))
+  (mu4e~proc-view msgid mu4e-view-show-images))
 
 (defun mu4e-view-message-text (msg)
   "Return the message to display (as a string), based on the MSG
@@ -215,6 +223,8 @@ marking if it still had that."
 	(mu4e~view-fontify-footer)
 	(mu4e~view-make-urls-clickable)
 
+	(mu4e~view-show-images-maybe msg)
+
 	(unless refresh
 	  ;; if we're showing the message for the first time, use the values of
 	  ;; user-settable variables `mu4e~view-wrap-lines' and
@@ -322,6 +332,15 @@ is nil, and otherwise open it."
     (unless (zerop id)
       (mu4e~view-construct-header (format "Attachments(%d)" id) attstr t))))
 
+(defun mu4e-view-for-each-part (msg func)
+  "Apply FUNC to each part in MSG. FUNC should be a function taking two arguments;
+ 1. the message MSG, and
+ 2. a plist describing the attachment. The plist looks like:
+    	 (:index 1 :name \"test123.doc\"
+          :mime-type \"application/msword\" :attachment t :size 1234)."
+  (dolist (part (mu4e-msg-field msg :parts))
+    (funcall func msg part)))
+
 
 (defvar mu4e-view-mode-map nil
   "Keymap for \"*mu4e-view*\" buffers.")
@@ -571,6 +590,18 @@ Seen; if the message is not New/Unread, do nothing."
       (browse-url url))))
 
 
+(defun mu4e~view-show-images-maybe (msg)
+  "Show attached images, if `mu4e-view-show-images' is non-nil."
+  (when (and (display-images-p) mu4e-view-show-images)
+    (mu4e-view-for-each-part msg
+      (lambda (msg part)
+	(when (string-match "^image/" (plist-get part :mime-type))
+	  (let ((imgfile (plist-get part :temp)))
+	    (when (and imgfile (file-exists-p imgfile))
+	      (save-excursion
+		(goto-char (point-max))
+		(mu4e-display-image imgfile mu4e-view-image-max-width)))))))))
+		
 ;; this is fairly simplistic...
 (defun mu4e~view-make-urls-clickable ()
   "Turn things that look like URLs into clickable things, and
@@ -595,7 +626,6 @@ number them so they can be opened using `mu4e-view-go-to-url'."
 			     'face 'mu4e-view-url-number-face))))))))
 
 
-
 (defun mu4e~view-wrap-lines ()
   "Wrap lines in the message body."
   (save-excursion

emacs/mu4e.texi

@@ -748,6 +748,26 @@ variable @code{mu4e-attachment-dir}, for example:
 (setq mu4e-attachment-dir (file-name-expand "~/Downloads"))
 @end lisp
 
+@subsection Viewing images inline
+
+It is possible to show images inline in the message view buffer if you run
+emacs in GUI-mode. You can enable this by setting the variable
+@code{mu4e-view-show-images} to @t{t}.
+
+Since emacs does not always handle images correctly, this is not enabled by
+default. Note, if you are using a (pre-) release of emacs 24 and build it
+yourself, you probable want to build it with @emph{Imagemagick} support -- in
+that case, also make sure you call @code{imagemagick-register-types} in your
+configuration, so it is used for images.
+
+@lisp
+;; enable inline images
+(setq mu4e-view-show-images-t)
+;; use imagemagick, if available
+(when (fboundp 'imagemagick-register-types)
+   (imagemagick-register-types))
+@end lisp
+
 @subsection Actions
 
 @code{mu4e-view-action} (@key{a}) lets you pick some custom action to perform