[PATCH 1/3 v2] emacs: Rework crypto switch toggle.

[David Edmondson]

Re-work the existing crypto switch toggle to be based on a persistant
buffer-local variable.

To allow this, modify `notmuch-show-refresh-view' to erase and re-draw
in the current buffer rather than killing the current buffer and
creating a new one. (This will also allow more per-buffer behaviour in
future patches.)

Add a binding ('$') to toggle crypto processing of the current buffer
and remove the prefix argument approach that achieves a similar
result.
---
 emacs/notmuch-show.el |  105 +++++++++++++++++++++++-------------------------
 emacs/notmuch.el      |    7 +--
 2 files changed, 53 insertions(+), 59 deletions(-)

diff --git a/emacs/notmuch-show.el b/emacs/notmuch-show.el
index 84ac624..53f6ae4 100644
--- a/emacs/notmuch-show.el
+++ b/emacs/notmuch-show.el
@@ -124,6 +124,17 @@ indentation."
 		 (const :tag "View interactively"
 			notmuch-show-interactively-view-part)))
 
+(defvar notmuch-show-thread-id nil)
+(make-variable-buffer-local 'notmuch-show-thread-id)
+(defvar notmuch-show-parent-buffer nil)
+(make-variable-buffer-local 'notmuch-show-parent-buffer)
+(defvar notmuch-show-query-context nil)
+(make-variable-buffer-local 'notmuch-show-query-context)
+
+(defvar notmuch-show-process-crypto nil)
+(make-variable-buffer-local 'notmuch-show-process-crypto)
+(put 'notmuch-show-process-crypto 'permanent-local t)
+
 (defmacro with-current-notmuch-show-message (&rest body)
   "Evaluate body with current buffer set to the text of current message"
   `(save-excursion
@@ -410,14 +421,11 @@ message at DEPTH in the current thread."
 
 (defmacro notmuch-with-temp-part-buffer (message-id nth &rest body)
   (declare (indent 2))
-  (let ((process-crypto (make-symbol "process-crypto")))
-    `(let ((,process-crypto notmuch-show-process-crypto))
-       (with-temp-buffer
-	 (setq notmuch-show-process-crypto ,process-crypto)
-	 ;; Always acquires the part via `notmuch part', even if it is
-	 ;; available in the JSON output.
-	 (insert (notmuch-show-get-bodypart-internal ,message-id ,nth))
-	 , at body))))
+  `(with-temp-buffer
+     ;; Always acquires the part via `notmuch part', even if it is
+     ;; available in the JSON output.
+     (insert (notmuch-show-get-bodypart-internal ,message-id ,nth))
+     , at body))
 
 (defun notmuch-show-save-part (message-id nth &optional filename content-type)
   (notmuch-with-temp-part-buffer message-id nth
@@ -599,7 +607,7 @@ current buffer, if possible."
 	       (sigstatus (car (plist-get part :sigstatus))))
 	  (notmuch-crypto-insert-sigstatus-button sigstatus from))
       ;; if we're not adding sigstatus, tell the user how they can get it
-      (button-put button 'help-echo "Set notmuch-crypto-process-mime to process cryptographic mime parts.")))
+      (button-put button 'help-echo "Set notmuch-crypto-process-mime to process cryptographic MIME parts.")))
 
   (let ((inner-parts (plist-get part :content))
 	(start (point)))
@@ -625,7 +633,7 @@ current buffer, if possible."
 		     (sigstatus (car (plist-get part :sigstatus))))
 		(notmuch-crypto-insert-sigstatus-button sigstatus from))))
       ;; if we're not adding encstatus, tell the user how they can get it
-      (button-put button 'help-echo "Set notmuch-crypto-process-mime to process cryptographic mime parts.")))
+      (button-put button 'help-echo "Set notmuch-crypto-process-mime to process cryptographic MIME parts.")))
 
   (let ((inner-parts (plist-get part :content))
 	(start (point)))
@@ -752,8 +760,6 @@ current buffer, if possible."
 
 ;; Helper for parts which are generally not included in the default
 ;; JSON output.
-;; Uses the buffer-local variable notmuch-show-process-crypto to
-;; determine if parts should be decrypted first.
 (defun notmuch-show-get-bodypart-internal (message-id part-number)
   (let ((args '("show" "--format=raw"))
 	(part-arg (format "--part=%s" part-number)))
@@ -907,6 +913,15 @@ current buffer, if possible."
     ;; criteria.
     (notmuch-show-message-visible msg (plist-get msg :match))))
 
+(defun notmuch-show-toggle-process-crypto ()
+  "Toggle the processing of cryptographic MIME parts."
+  (interactive)
+  (setq notmuch-show-process-crypto (not notmuch-show-process-crypto))
+  (message (if notmuch-show-process-crypto
+	       "Processing cryptographic MIME parts."
+	     "Not processing cryptographic MIME parts."))
+  (notmuch-show-refresh-view))
+
 (defun notmuch-show-insert-tree (tree depth)
   "Insert the message tree TREE at depth DEPTH in the current thread."
   (let ((msg (car tree))
@@ -922,15 +937,6 @@ current buffer, if possible."
   "Insert the forest of threads FOREST."
   (mapc (lambda (thread) (notmuch-show-insert-thread thread 0)) forest))
 
-(defvar notmuch-show-thread-id nil)
-(make-variable-buffer-local 'notmuch-show-thread-id)
-(defvar notmuch-show-parent-buffer nil)
-(make-variable-buffer-local 'notmuch-show-parent-buffer)
-(defvar notmuch-show-query-context nil)
-(make-variable-buffer-local 'notmuch-show-query-context)
-(defvar notmuch-show-buffer-name nil)
-(make-variable-buffer-local 'notmuch-show-buffer-name)
-
 (defun notmuch-show-buttonise-links (start end)
   "Buttonise URLs and mail addresses between START and END.
 
@@ -950,7 +956,7 @@ a corresponding notmuch search."
 			'face goto-address-mail-face))))
 
 ;;;###autoload
-(defun notmuch-show (thread-id &optional parent-buffer query-context buffer-name crypto-switch)
+(defun notmuch-show (thread-id &optional parent-buffer query-context buffer-name)
   "Run \"notmuch show\" with the given thread ID and display results.
 
 The optional PARENT-BUFFER is the notmuch-search buffer from
@@ -965,24 +971,20 @@ non-nil.
 The optional BUFFER-NAME provides the name of the buffer in
 which the message thread is shown. If it is nil (which occurs
 when the command is called interactively) the argument to the
-function is used.
-
-The optional CRYPTO-SWITCH toggles the value of the
-notmuch-crypto-process-mime customization variable for this show
-buffer."
+function is used."
   (interactive "sNotmuch show: ")
-  (let* ((process-crypto (if crypto-switch
-			     (not notmuch-crypto-process-mime)
-			   notmuch-crypto-process-mime)))
-    (notmuch-show-worker thread-id parent-buffer query-context buffer-name process-crypto)))
-
-(defun notmuch-show-worker (thread-id parent-buffer query-context buffer-name process-crypto)
-  (let* ((buffer-name (generate-new-buffer-name
-		       (or buffer-name
-			   (concat "*notmuch-" thread-id "*"))))
-	 (buffer (get-buffer-create buffer-name))
-	 (inhibit-read-only t))
-    (switch-to-buffer buffer)
+  (let ((buffer-name (generate-new-buffer-name
+		      (or buffer-name
+			  (concat "*notmuch-" thread-id "*")))))
+    (switch-to-buffer (get-buffer-create buffer-name))
+    ;; Set the default value for `notmuch-show-process-crypto' in this
+    ;; buffer.
+    (setq notmuch-show-process-crypto notmuch-crypto-process-mime)
+    (notmuch-show-worker thread-id parent-buffer query-context)))
+
+(defun notmuch-show-worker (thread-id parent-buffer query-context)
+  (let ((inhibit-read-only t))
+
     (notmuch-show-mode)
     ;; Don't track undo information for this buffer
     (set 'buffer-undo-list t)
@@ -990,8 +992,6 @@ buffer."
     (setq notmuch-show-thread-id thread-id)
     (setq notmuch-show-parent-buffer parent-buffer)
     (setq notmuch-show-query-context query-context)
-    (setq notmuch-show-buffer-name buffer-name)
-    (setq notmuch-show-process-crypto process-crypto)
 
     (erase-buffer)
     (goto-char (point-min))
@@ -1021,21 +1021,15 @@ buffer."
 
     (notmuch-show-mark-read)))
 
-(defun notmuch-show-refresh-view (&optional crypto-switch)
-  "Refresh the current view (with crypto switch if prefix given).
+(defun notmuch-show-refresh-view ()
+  "Refresh the current view.
 
-Kills the current buffer and reruns notmuch show with the same
-thread id.  If a prefix is given, crypto processing is toggled."
-  (interactive "P")
-  (let ((thread-id notmuch-show-thread-id)
-	(parent-buffer notmuch-show-parent-buffer)
-	(query-context notmuch-show-query-context)
-	(buffer-name notmuch-show-buffer-name)
-	(process-crypto (if crypto-switch
-			    (not notmuch-show-process-crypto)
-			  notmuch-show-process-crypto)))
-    (notmuch-kill-this-buffer)
-    (notmuch-show-worker thread-id parent-buffer query-context buffer-name process-crypto)))
+Refreshes the current view, observing changes in cryptographic preferences."
+  (interactive)
+  (let ((inhibit-read-only t))
+    (erase-buffer))
+  (notmuch-show-worker notmuch-show-thread-id notmuch-show-parent-buffer
+		       notmuch-show-query-context))
 
 (defvar notmuch-show-stash-map
   (let ((map (make-sparse-keymap)))
@@ -1085,6 +1079,7 @@ thread id.  If a prefix is given, crypto processing is toggled."
 	(define-key map (kbd "M-RET") 'notmuch-show-open-or-close-all)
 	(define-key map (kbd "RET") 'notmuch-show-toggle-message)
 	(define-key map "#" 'notmuch-show-print-message)
+	(define-key map "$" 'notmuch-show-toggle-process-crypto)
 	map)
       "Keymap for \"notmuch show\" buffers.")
 (fset 'notmuch-show-mode-map notmuch-show-mode-map)
diff --git a/emacs/notmuch.el b/emacs/notmuch.el
index 72f78ed..9d8bebd 100644
--- a/emacs/notmuch.el
+++ b/emacs/notmuch.el
@@ -463,9 +463,9 @@ Complete list of currently available key bindings:
   "Return a list of authors for the current region"
   (notmuch-search-properties-in-region 'notmuch-search-subject beg end))
 
-(defun notmuch-search-show-thread (&optional crypto-switch)
+(defun notmuch-search-show-thread ()
   "Display the currently selected thread."
-  (interactive "P")
+  (interactive)
   (let ((thread-id (notmuch-search-find-thread-id))
 	(subject (notmuch-search-find-subject)))
     (if (> (length thread-id) 0)
@@ -479,8 +479,7 @@ Complete list of currently available key bindings:
 			 (concat "*"
 				 (truncate-string-to-width subject 32 nil nil t)
 				 "*")
-			 32 nil nil t))
-		      crypto-switch)
+			 32 nil nil t)))
       (message "End of search results."))))
 
 (defun notmuch-search-reply-to-thread (&optional prompt-for-sender)
-- 
1.7.8.3