[PATCH 1/2] emacs: address completion, allow sender/recipient and filters

[Mark Walters <markwalters1009@gmail.com>]

This commit lets the user customize the address completion. It makes
two changes.

The first change controls whether to build the address completion list
based on messages you have sent or you have received (the latter is
much faster).

The second change add a possible filter query to limit the messages
used -- for example, setting this to date:1y..  would limit the
address completions to addresses used in the last year. This speeds up
the address harvest and may also make the search less cluttered as old
addresses may well no longer be valid.
---
 emacs/notmuch-address.el | 135 +++++++++++++++++++++++++++++++++--------------
 emacs/notmuch-company.el |   2 +-
 emacs/notmuch-mua.el     |   3 +-
 3 files changed, 98 insertions(+), 42 deletions(-)

diff --git a/emacs/notmuch-address.el b/emacs/notmuch-address.el
index aafbe5f..3e7bdab 100644
--- a/emacs/notmuch-address.el
+++ b/emacs/notmuch-address.el
@@ -28,15 +28,62 @@
 ;;
 (declare-function company-manual-begin "company")
 
+(defvar notmuch-address-last-harvest 0
+  "Time of last address harvest")
+
+(defvar notmuch-address-completions (make-hash-table :test 'equal)
+  "Hash of email addresses for completion during email composition.
+  This variable is set by calling `notmuch-address-harvest'.")
+
+(defvar notmuch-address-full-harvest-finished nil
+  "t indicates that full completion address harvesting has been
+finished")
+
 (defcustom notmuch-address-command 'internal
-  "The command which generates possible addresses. It must take a
-single argument and output a list of possible matches, one per
-line. The default value of `internal' uses built-in address
-completion."
+  "Determines how address completion candidates are generated.
+
+If it is a string then that string should be an external program
+which must take a single argument (searched string) and output a
+list of completion candidates, one per line.
+
+Alternatively, it can be the symbol 'internal, in which case
+internal completion is used; the variable
+`notmuch-address-internal-completion` can be used to customize
+this case.
+
+Finally, if this variable is nil then address completion is
+disabled."
   :type '(radio
 	  (const :tag "Use internal address completion" internal)
 	  (const :tag "Disable address completion" nil)
-	  (string :tag "Use external completion command" "notmuch-addresses"))
+	  (string :tag "Use external completion command"))
+  :group 'notmuch-send
+  :group 'notmuch-external)
+
+(defcustom notmuch-address-internal-completion '(sent nil)
+  "Determines how internal address completion generates candidates.
+
+This should be a list of the form '(DIRECTION FILTER), where
+ DIRECTION is either sent or received and specifies whether the
+ candidates are searched in messages sent by the user or received
+ by the user (note received by is much faster), and FILTER is
+ either nil or a filter-string, such as \"date:1y..\" to append
+ to the query."
+  :type '(list :tag "Use internal address completion"
+	       (radio
+		:tag "Base completion on messages you have"
+		:value sent
+		(const :tag "sent (more accurate)" sent)
+		(const :tag "received (faster)" received))
+	       (radio :tag "Filter messages used for completion"
+		      (const :tag "Use all messages" nil)
+		      (string :tag "Filter query")))
+  ;; We override set so that we can clear the cache when this changes
+  :set (lambda (symbol value)
+	 (set-default symbol value)
+	 (setq notmuch-address-last-harvest 0)
+	 (setq notmuch-address-completions (clrhash notmuch-address-completions))
+	 (setq notmuch-address-full-harvest-finished nil))
   :group 'notmuch-send
   :group 'notmuch-external)
 
@@ -51,17 +98,6 @@ to know how address selection is made by default."
   :group 'notmuch-send
   :group 'notmuch-external)
 
-(defvar notmuch-address-last-harvest 0
-  "Time of last address harvest")
-
-(defvar notmuch-address-completions (make-hash-table :test 'equal)
-  "Hash of email addresses for completion during email composition.
-  This variable is set by calling `notmuch-address-harvest'.")
-
-(defvar notmuch-address-full-harvest-finished nil
-  "t indicates that full completion address harvesting has been
-finished")
-
 (defun notmuch-address-selection-function (prompt collection initial-input)
   "Call (`completing-read'
       PROMPT COLLECTION nil nil INITIAL-INPUT 'notmuch-address-history)"
@@ -86,9 +122,7 @@ finished")
 			   (eq notmuch-address-command 'internal)
 			   (require 'company nil t)))
 	 (pair (cons notmuch-address-completion-headers-regexp
-		     (if use-company
-			 #'company-manual-begin
-		       #'notmuch-address-expand-name))))
+		       #'notmuch-address-expand-name)))
       (when use-company
 	(notmuch-company-setup))
       (unless (memq pair message-completion-alist)
@@ -115,7 +149,7 @@ external commands."
     (when (not notmuch-address-full-harvest-finished)
       ;; First, run quick synchronous harvest based on what the user
       ;; entered so far
-      (notmuch-address-harvest (format "to:%s*" original) t))
+      (notmuch-address-harvest original t))
     (prog1 (notmuch-address-matching original)
       ;; Then start the (potentially long-running) full asynchronous harvest if necessary
       (notmuch-address-harvest-trigger)))
@@ -123,7 +157,12 @@ external commands."
     (process-lines notmuch-address-command original))))
 
 (defun notmuch-address-expand-name ()
-  (when notmuch-address-command
+  (cond
+   ((and (eq notmuch-address-command 'internal)
+	 notmuch-address-use-company
+	 (bound-and-true-p company-mode))
+    (company-manual-begin))
+   (notmuch-address-command
     (let* ((end (point))
 	   (beg (save-excursion
 		  (re-search-backward "\\(\\`\\|[\n:,]\\)[ \t]*")
@@ -149,7 +188,8 @@ external commands."
 	    (delete-region beg end)
 	    (insert chosen))
 	(message "No matches.")
-	(ding)))))
+	(ding))))
+   (t nil)))
 
 ;; Copied from `w3m-which-command'.
 (defun notmuch-address-locate-command (command)
@@ -191,32 +231,49 @@ external commands."
 
 The car is a partial harvest, and the cdr is a full harvest")
 
-(defun notmuch-address-harvest (&optional filter-query synchronous callback)
-  "Collect addresses completion candidates. It queries the
-notmuch database for all messages sent by the user optionally
-matching FILTER-QUERY (if not nil). It collects the destination
-addresses from those messages and stores them in
-`notmuch-address-completions'. Address harvesting may take some
-time so the address collection runs asynchronously unless
-SYNCHRONOUS is t. In case of asynchronous execution, CALLBACK is
-called when harvesting finishes."
-  (let* ((from-me-query (mapconcat (lambda (x) (concat "from:" x)) (notmuch-user-emails) " or "))
-	 (query (if filter-query
-		    (format "(%s) and (%s)" from-me-query filter-query)
-		  from-me-query))
+(defun notmuch-address-harvest (&optional addr-prefix synchronous callback)
+  "Collect addresses completion candidates.
+
+It queries the notmuch database for messages sent/received (as
+configured with `notmuch-address-command`) by the user, collects
+destination/source addresses from those messages and stores them
+in `notmuch-address-completions'.
+
+If ADDR-PREFIX is not nil, only messages with to/from addresses
+matching ADDR-PREFIX*' are queried.
+
+Address harvesting may take some time so the address collection runs
+asynchronously unless SYNCHRONOUS is t. In case of asynchronous
+execution, CALLBACK is called when harvesting finishes."
+
+  (let* ((sent (eq (car notmuch-address-internal-completion) 'sent))
+	 (config-query (cadr notmuch-address-internal-completion))
+	 (prefix-query (when addr-prefix
+			 (format "%s:%s*" (if sent "to" "from") addr-prefix)))
+	 (from-or-to-me-query
+	  (mapconcat (lambda (x)
+		       (concat (if sent "from:" "to:") x))
+		     (notmuch-user-emails) " or "))
+	 (query (if (or prefix-query config-query)
+		    (concat (format "(%s)" from-or-to-me-query)
+			    (when prefix-query
+			      (format " and (%s)" prefix-query))
+			    (when config-query
+			      (format " and (%s)" config-query)))
+		  from-or-to-me-query))
 	 (args `("address" "--format=sexp" "--format-version=2"
-		 "--output=recipients"
+		 ,(if sent "--output=recipients" "--output=sender")
 		 "--deduplicate=address"
 		 ,query)))
     (if synchronous
 	(mapc #'notmuch-address-harvest-addr
 				   (apply 'notmuch-call-notmuch-sexp args))
       ;; Asynchronous
-      (let* ((current-proc (if filter-query
+      (let* ((current-proc (if addr-prefix
 			       (car notmuch-address-harvest-procs)
 			     (cdr notmuch-address-harvest-procs)))
 	     (proc-name (format "notmuch-address-%s-harvest"
-				(if filter-query "partial" "full")))
+				(if addr-prefix "partial" "full")))
 	     (proc-buf (concat " *" proc-name "*")))
 	;; Kill any existing process
 	(when current-proc
@@ -228,7 +285,7 @@ called when harvesting finishes."
 		     args))
 	(set-process-filter current-proc 'notmuch-address-harvest-filter)
 	(set-process-query-on-exit-flag current-proc nil)
-	(if filter-query
+	(if addr-prefix
 	    (setcar notmuch-address-harvest-procs current-proc)
 	  (setcdr notmuch-address-harvest-procs current-proc)))))
   ;; return value
diff --git a/emacs/notmuch-company.el b/emacs/notmuch-company.el
index b881d6d..dcb59cd 100644
--- a/emacs/notmuch-company.el
+++ b/emacs/notmuch-company.el
@@ -72,7 +72,7 @@
 			  (lambda (callback)
 			    ;; First run quick asynchronous harvest based on what the user entered so far
 			    (notmuch-address-harvest
-			     (format "to:%s*" arg) nil
+			     arg nil
 			     (lambda (_proc _event)
 			       (funcall callback (notmuch-address-matching arg))
 			       ;; Then start the (potentially long-running) full asynchronous harvest if necessary
diff --git a/emacs/notmuch-mua.el b/emacs/notmuch-mua.el
index 399e138..93a4d4b 100644
--- a/emacs/notmuch-mua.el
+++ b/emacs/notmuch-mua.el
@@ -276,8 +276,7 @@ mutiple parts get a header."
 
 (define-derived-mode notmuch-message-mode message-mode "Message[Notmuch]"
   "Notmuch message composition mode. Mostly like `message-mode'"
-  (when notmuch-address-command
-    (notmuch-address-setup)))
+  (notmuch-address-setup))
 
 (put 'notmuch-message-mode 'flyspell-mode-predicate 'mail-mode-flyspell-verify)
 
-- 
2.1.4