[PATCH 3/3] emacs: colorize buttonized 'id:' links depending on the target message's state

[Pieter Praet <pieter@praet.org>]

* emacs/notmuch-show.el (notmuch-show-buttonized-link-present),
* emacs/notmuch-show.el (notmuch-show-buttonized-link-present-and-unread),
* emacs/notmuch-show.el (notmuch-show-buttonized-link-missing):
  new faces for buttonized id: links.

* emacs/notmuch-show.el (notmuch-show-found-target-p): add optional arg
  VERIFY-UNREAD which causes results to be filtered by "tag:unread".

* emacs/notmuch-show.el (notmuch-show-buttonize-links): use different
  face property depending on the result of `notmuch-show-found-target-p',
  causing buttons to present, present-and-unread and missing messages to
  be displayed in a different color.
---
 emacs/notmuch-show.el |   32 +++++++++++++++++++++++++++++---
 1 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/emacs/notmuch-show.el b/emacs/notmuch-show.el
index 8f12955..25330c4 100644
--- a/emacs/notmuch-show.el
+++ b/emacs/notmuch-show.el
@@ -797,6 +797,27 @@ current buffer, if possible."
 (defvar notmuch-show-buffer-name nil)
 (make-variable-buffer-local 'notmuch-show-buffer-name)
 
+(defface notmuch-show-buttonized-link-present
+  '((t (:inherit goto-address-mail-face :foreground "blue")))
+  "Face used for buttonized links to messages which are present
+in the mail store."
+  :group 'notmuch-show
+  :group 'notmuch-appearance)
+
+(defface notmuch-show-buttonized-link-present-and-unread
+  '((t (:inherit goto-address-mail-face :foreground "green")))
+  "Face used for buttonized links to messages which are present
+in the mail store, and are tagged `unread'."
+  :group 'notmuch-show
+  :group 'notmuch-appearance)
+
+(defface notmuch-show-buttonized-link-missing
+  '((t (:inherit goto-address-mail-face :foreground "red")))
+  "Face used for buttonized links to messages which are NOT
+present in in the mail store."
+  :group 'notmuch-show
+  :group 'notmuch-appearance)
+
 (defun notmuch-show-buttonize-links (start end)
   "Buttonize URLs and mail addresses between START and END.
 
@@ -816,7 +837,12 @@ a corresponding notmuch search."
 				   (notmuch-show-if-found ,message-id))
 			'follow-link t
 			'help-echo "Mouse-1, RET: search for this message"
-			'face goto-address-mail-face))))
+			'face (cond
+			       ((notmuch-show-found-target-p message-id t)
+				'notmuch-show-buttonized-link-present-and-unread)
+			       ((notmuch-show-found-target-p message-id)
+				'notmuch-show-buttonized-link-present)
+			       (t 'notmuch-show-buttonized-link-missing)))))))
 
 ;;;###autoload
 (defun notmuch-show (thread-id &optional parent-buffer query-context buffer-name crypto-switch)
@@ -909,8 +935,8 @@ thread id.  If a prefix is given, crypto processing is toggled."
     (notmuch-kill-this-buffer)
     (notmuch-show-worker thread-id parent-buffer query-context buffer-name process-crypto)))
 
-(defun notmuch-show-found-target-p (target)
-  (let ((args `("count" ,target)))
+(defun notmuch-show-found-target-p (target &optional verify-unread)
+  (let ((args `("count" ,target ,(if verify-unread "and tag:unread" ""))))
     (> (string-to-number (substring
       (with-output-to-string
         (apply 'call-process notmuch-command nil standard-output nil args))
-- 
1.7.8.1