[PATCH v3 1/4] emacs: Let the user choose where to compose new mails

[Thomas Jost]

Reusing the current window to compose a new mail may be troublesome for the
user. This patch introduces a new customizable variable, notmuch-mua-compose-in,
which lets the user choose where to create the mail buffer: in the current
window (current and default behaviour), in a new window, or in a new frame.
---
 emacs/notmuch-mua.el |   40 ++++++++++++++++++++++++++++++++++++++--
 1 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/emacs/notmuch-mua.el b/emacs/notmuch-mua.el
index 8824b08..90834d6 100644
--- a/emacs/notmuch-mua.el
+++ b/emacs/notmuch-mua.el
@@ -31,6 +31,21 @@
   :group 'notmuch
   :type 'hook)
 
+(defcustom notmuch-mua-compose-in 'current-window
+  "Where to create the mail buffer used to compose a new message.
+  Possible values are `current-window' (default), `new-window'
+  and `new-frame'. If set to `current-window', the mail buffer
+  will be displayed in the current window, so the old buffer will
+  be restored when the mail buffer is killed. If set to
+  `new-window' or `new-frame', the mail buffer will be displayed
+  in a new window/frame that will be destroyed when the buffer is
+  killed. You may want to customize `message-kill-buffer-on-exit'
+  accordingly."
+  :group 'notmuch
+  :type '(choice (const :tag "Compose in the current window" current-window)
+		 (const :tag "Compose mail in a new window"  new-window)
+		 (const :tag "Compose mail in a new frame"   new-frame)))
+
 (defcustom notmuch-mua-user-agent-function 'notmuch-mua-user-agent-full
   "Function used to generate a `User-Agent:' string. If this is
 `nil' then no `User-Agent:' will be generated."
@@ -48,6 +63,23 @@ list."
 
 ;;
 
+(defun notmuch-mua-get-switch-function ()
+  "Get a switch function according to `notmuch-mua-compose-in'."
+  (cond ((eq notmuch-mua-compose-in 'current-window)
+	 'switch-to-buffer)
+	((eq notmuch-mua-compose-in 'new-window)
+	 'switch-to-buffer-other-window)
+	((eq notmuch-mua-compose-in 'new-frame)
+	 'switch-to-buffer-other-frame)
+	(t (error "Invalid value for `notmuch-mua-compose-in'"))))
+
+(defun notmuch-mua-maybe-set-window-dedicated ()
+  "Set the selected window as dedicated according to
+`notmuch-mua-compose-in'."
+  (when (or (eq notmuch-mua-compose-in 'new-frame)
+	    (eq notmuch-mua-compose-in 'new-window))
+    (set-window-dedicated-p (selected-window) t)))
+
 (defun notmuch-mua-user-agent-full ()
   "Generate a `User-Agent:' string suitable for notmuch."
   (concat (notmuch-mua-user-agent-notmuch)
@@ -99,7 +131,8 @@ list."
 	((same-window-regexps '("\\*mail .*")))
       (notmuch-mua-mail (mail-header 'to headers)
 			(mail-header 'subject headers)
-			(message-headers-to-generate headers t '(to subject))))
+			(message-headers-to-generate headers t '(to subject))
+			nil (notmuch-mua-get-switch-function)))
     ;; insert the message body - but put it in front of the signature
     ;; if one is present
     (goto-char (point-max))
@@ -112,6 +145,7 @@ list."
   (message-goto-body))
 
 (defun notmuch-mua-forward-message ()
+  (funcall (notmuch-mua-get-switch-function) (current-buffer))
   (message-forward)
 
   (when notmuch-mua-user-agent-function
@@ -121,6 +155,7 @@ list."
   (message-sort-headers)
   (message-hide-headers)
   (set-buffer-modified-p nil)
+  (notmuch-mua-maybe-set-window-dedicated)
 
   (message-goto-to))
 
@@ -143,6 +178,7 @@ list."
   (message-sort-headers)
   (message-hide-headers)
   (set-buffer-modified-p nil)
+  (notmuch-mua-maybe-set-window-dedicated)
 
   (message-goto-to))
 
@@ -199,7 +235,7 @@ the From: address first."
   (let ((other-headers
 	 (when (or prompt-for-sender notmuch-always-prompt-for-sender)
 	   (list (cons 'from (notmuch-mua-prompt-for-sender))))))
-    (notmuch-mua-mail nil nil other-headers)))
+    (notmuch-mua-mail nil nil other-headers nil (notmuch-mua-get-switch-function))))
 
 (defun notmuch-mua-new-forward-message (&optional prompt-for-sender)
   "Invoke the notmuch message forwarding window.
-- 
1.7.8