;; notmuch.el --- run notmuch within emacs
;;
;; Copyright © Carl Worth
;;
;; This file is part of Notmuch.
;;
;; Notmuch is free software: you can redistribute it and/or modify it
;; under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.
;;
;; Notmuch is distributed in the hope that it will be useful, but
;; WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
;; General Public License for more details.
;;
;; You should have received a copy of the GNU General Public License
;; along with Notmuch.  If not, see <http://www.gnu.org/licenses/>.
;;
;; Authors: Carl Worth <cworth@cworth.org>

;; This is an emacs-based interface to the notmuch mail system.
;;
;; You will first need to have the notmuch program installed and have a
;; notmuch database built in order to use this. See
;; http://notmuchmail.org for details.
;;
;; To install this software, copy it to a directory that is on the
;; `load-path' variable within emacs (a good candidate is
;; /usr/local/share/emacs/site-lisp). If you are viewing this from the
;; notmuch source distribution then you can simply run:
;;
;;	sudo make install-emacs
;;
;; to install it.
;;
;; Then, to actually run it, add:
;;
;;	(require 'notmuch)
;;
;; to your ~/.emacs file, and then run "M-x notmuch" from within emacs,
;; or run:
;;
;;	emacs -f notmuch
;;
;; Have fun, and let us know if you have any comment, questions, or
;; kudos: Notmuch list <notmuch@notmuchmail.org> (subscription is not
;; required, but is available from http://notmuchmail.org).

(eval-when-compile (require 'cl))
(require 'crm)
(require 'mm-view)
(require 'message)

(require 'notmuch-lib)
(require 'notmuch-show)
(require 'notmuch-mua)
(require 'notmuch-hello)
(require 'notmuch-maildir-fcc)
(require 'notmuch-message)

(defcustom notmuch-search-result-format
  `(("date" . "%s ")
    ("count" . "%-7s ")
    ("authors" . "%-20s ")
    ("subject" . "%s ")
    ("tags" . "(%s)"))
  "Search result formatting. Supported fields are:
	date, count, authors, subject, tags
For example:
	(setq notmuch-search-result-format \(\(\"authors\" . \"%-40s\"\)
					     \(\"subject\" . \"%s\"\)\)\)"
  :type '(alist :key-type (string) :value-type (string))
  :group 'notmuch-search)

(defvar notmuch-query-history nil
  "Variable to store minibuffer history for notmuch queries")

(defvar notmuch-select-tag-history nil
  "Variable to store minibuffer history for
`notmuch-select-tag-with-completion' function.")

(defvar notmuch-read-tag-changes-history nil
  "Variable to store minibuffer history for
`notmuch-read-tag-changes' function.")

(defun notmuch-tag-completions (&optional search-terms)
  (split-string
   (with-output-to-string
     (with-current-buffer standard-output
       (apply 'call-process notmuch-command nil t
	      nil "search-tags" search-terms)))
   "\n+" t))

(defun notmuch-select-tag-with-completion (prompt &rest search-terms)
  (let ((tag-list (notmuch-tag-completions search-terms)))
    (completing-read prompt tag-list nil nil nil 'notmuch-select-tag-history)))

(defun notmuch-read-tag-changes (&optional initial-input &rest search-terms)
  (let* ((all-tag-list (notmuch-tag-completions))
	 (add-tag-list (mapcar (apply-partially 'concat "+") all-tag-list))
	 (remove-tag-list (mapcar (apply-partially 'concat "-")
				  (if (null search-terms)
				      all-tag-list
				    (notmuch-tag-completions search-terms))))
	 (tag-list (append add-tag-list remove-tag-list))
	 (crm-separator " ")
	 ;; By default, space is bound to "complete word" function.
	 ;; Re-bind it to insert a space instead.  Note that <tab>
	 ;; still does the completion.
	 (crm-local-completion-map
	  (let ((map (make-sparse-keymap)))
	    (set-keymap-parent map crm-local-completion-map)
	    (define-key map " " 'self-insert-command)
	    map)))
    (delete "" (completing-read-multiple "Tags (+add -drop): "
		tag-list nil nil initial-input
		'notmuch-read-tag-changes-history))))

(defun notmuch-update-tags (tags tag-changes)
  "Return a copy of TAGS with additions and removals from TAG-CHANGES.

TAG-CHANGES must be a list of tags names, each prefixed with
either a \"+\" to indicate the tag should be added to TAGS if not
present or a \"-\" to indicate that the tag should be removed
from TAGS if present."
  (let ((result-tags (copy-sequence tags)))
    (dolist (tag-change tag-changes)
      (let ((op (string-to-char tag-change))
	    (tag (unless (string= tag-change "") (substring tag-change 1))))
	(case op
	  (?+ (unless (member tag result-tags)
		(push tag result-tags)))
	  (?- (setq result-tags (delete tag result-tags)))
	  (otherwise
	   (error "Changed tag must be of the form `+this_tag' or `-that_tag'")))))
    (sort result-tags 'string<)))

(defun notmuch-foreach-mime-part (function mm-handle)
  (cond ((stringp (car mm-handle))
         (dolist (part (cdr mm-handle))
           (notmuch-foreach-mime-part function part)))
        ((bufferp (car mm-handle))
         (funcall function mm-handle))
        (t (dolist (part mm-handle)
             (notmuch-foreach-mime-part function part)))))

(defun notmuch-count-attachments (mm-handle)
  (let ((count 0))
    (notmuch-foreach-mime-part
     (lambda (p)
       (let ((disposition (mm-handle-disposition p)))
         (and (listp disposition)
              (or (equal (car disposition) "attachment")
                  (and (equal (car disposition) "inline")
                       (assq 'filename disposition)))
              (incf count))))
     mm-handle)
    count))

(defun notmuch-save-attachments (mm-handle &optional queryp)
  (notmuch-foreach-mime-part
   (lambda (p)
     (let ((disposition (mm-handle-disposition p)))
       (and (listp disposition)
            (or (equal (car disposition) "attachment")
                (and (equal (car disposition) "inline")
                     (assq 'filename disposition)))
            (or (not queryp)
                (y-or-n-p
                 (concat "Save '" (cdr (assq 'filename disposition)) "' ")))
            (mm-save-part p))))
   mm-handle))

(defun notmuch-documentation-first-line (symbol)
  "Return the first line of the documentation string for SYMBOL."
  (let ((doc (documentation symbol)))
    (if doc
	(with-temp-buffer
	  (insert (documentation symbol t))
	  (goto-char (point-min))
	  (let ((beg (point)))
	    (end-of-line)
	    (buffer-substring beg (point))))
      "")))

(defun notmuch-prefix-key-description (key)
  "Given a prefix key code, return a human-readable string representation.

This is basically just `format-kbd-macro' but we also convert ESC to M-."
  (let ((desc (format-kbd-macro (vector key))))
    (if (string= desc "ESC")
	"M-"
      (concat desc " "))))

;; I would think that emacs would have code handy for walking a keymap
;; and generating strings for each key, and I would prefer to just call
;; that. But I couldn't find any (could be all implemented in C I
;; suppose), so I wrote my own here.
(defun notmuch-substitute-one-command-key-with-prefix (prefix binding)
  "For a key binding, return a string showing a human-readable
representation of the prefixed key as well as the first line of
documentation from the bound function.

For a mouse binding, return nil."
  (let ((key (car binding))
	(action (cdr binding)))
    (if (mouse-event-p key)
	nil
      (if (keymapp action)
	  (let ((substitute (apply-partially 'notmuch-substitute-one-command-key-with-prefix (notmuch-prefix-key-description key)))
		(as-list))
	    (map-keymap (lambda (a b)
			  (push (cons a b) as-list))
			action)
	    (mapconcat substitute as-list "\n"))
	(concat prefix (format-kbd-macro (vector key))
		"\t"
		(notmuch-documentation-first-line action))))))

(defun notmuch-substitute-command-keys-one (key)
  ;; A `keymap' key indicates inheritance from a parent keymap - the
  ;; inherited mappings follow, so there is nothing to print for
  ;; `keymap' itself.
  (when (not (eq key 'keymap))
    (notmuch-substitute-one-command-key-with-prefix nil key)))

(defun notmuch-substitute-command-keys (doc)
  "Like `substitute-command-keys' but with documentation, not function names."
  (let ((beg 0))
    (while (string-match "\\\\{\\([^}[:space:]]*\\)}" doc beg)
      (let* ((keymap-name (substring doc (match-beginning 1) (match-end 1)))
	     (keymap (symbol-value (intern keymap-name))))
	(setq doc (replace-match
		   (mapconcat #'notmuch-substitute-command-keys-one
			      (cdr keymap) "\n")
		   1 1 doc)))
      (setq beg (match-end 0)))
    doc))

(defun notmuch-help ()
  "Display help for the current notmuch mode."
  (interactive)
  (let* ((mode major-mode)
	 (doc (substitute-command-keys (notmuch-substitute-command-keys (documentation mode t)))))
    (with-current-buffer (generate-new-buffer "*notmuch-help*")
      (insert doc)
      (goto-char (point-min))
      (set-buffer-modified-p nil)
      (view-buffer (current-buffer) 'kill-buffer-if-not-modified))))

(require 'hl-line)

(defun notmuch-hl-line-mode ()
  (prog1 (hl-line-mode)
    (when hl-line-overlay
      (overlay-put hl-line-overlay 'priority 1))))

(defcustom notmuch-search-hook '(notmuch-hl-line-mode)
  "List of functions to call when notmuch displays the search results."
  :type 'hook
  :options '(notmuch-hl-line-mode)
  :group 'notmuch-search
  :group 'notmuch-hooks)

(defvar notmuch-search-mode-map
  (let ((map (make-sparse-keymap)))
    (define-key map "?" 'notmuch-help)
    (define-key map "q" 'notmuch-search-quit)
    (define-key map "x" 'notmuch-search-quit)
    (define-key map (kbd "<DEL>") 'notmuch-search-scroll-down)
    (define-key map "b" 'notmuch-search-scroll-down)
    (define-key map " " 'notmuch-search-scroll-up)
    (define-key map "<" 'notmuch-search-first-thread)
    (define-key map ">" 'notmuch-search-last-thread)
    (define-key map "p" 'notmuch-search-previous-thread)
    (define-key map "n" 'notmuch-search-next-thread)
    (define-key map "r" 'notmuch-search-reply-to-thread-sender)
    (define-key map "R" 'notmuch-search-reply-to-thread)
    (define-key map "m" 'notmuch-mua-new-mail)
    (define-key map "s" 'notmuch-search)
    (define-key map "o" 'notmuch-search-toggle-order)
    (define-key map "c" 'notmuch-search-stash-map)
    (define-key map "=" 'notmuch-search-refresh-view)
    (define-key map "G" 'notmuch-search-poll-and-refresh-view)
    (define-key map "t" 'notmuch-search-filter-by-tag)
    (define-key map "f" 'notmuch-search-filter)
    (define-key map [mouse-1] 'notmuch-search-show-thread)
    (define-key map "*" 'notmuch-search-tag-all)
    (define-key map "a" 'notmuch-search-archive-thread)
    (define-key map "-" 'notmuch-search-remove-tag)
    (define-key map "+" 'notmuch-search-add-tag)
    (define-key map (kbd "RET") 'notmuch-search-show-thread)
    map)
  "Keymap for \"notmuch search\" buffers.")
(fset 'notmuch-search-mode-map notmuch-search-mode-map)

(defvar notmuch-search-stash-map
  (let ((map (make-sparse-keymap)))
    (define-key map "i" 'notmuch-search-stash-thread-id)
    map)
  "Submap for stash commands")
(fset 'notmuch-search-stash-map notmuch-search-stash-map)

(defun notmuch-search-stash-thread-id ()
  "Copy thread ID of current thread to kill-ring."
  (interactive)
  (notmuch-common-do-stash (notmuch-search-find-thread-id)))

(defvar notmuch-search-query-string)
(defvar notmuch-search-target-thread)
(defvar notmuch-search-target-line)
(defvar notmuch-search-continuation)

(defvar notmuch-search-disjunctive-regexp      "\\<[oO][rR]\\>")

(defun notmuch-search-quit ()
  "Exit the search buffer, calling any defined continuation function."
  (interactive)
  (let ((continuation notmuch-search-continuation))
    (notmuch-kill-this-buffer)
    (when continuation
      (funcall continuation))))

(defun notmuch-search-scroll-up ()
  "Move forward through search results by one window's worth."
  (interactive)
  (condition-case nil
      (scroll-up nil)
    ((end-of-buffer) (notmuch-search-last-thread))))

(defun notmuch-search-scroll-down ()
  "Move backward through the search results by one window's worth."
  (interactive)
  ;; I don't know why scroll-down doesn't signal beginning-of-buffer
  ;; the way that scroll-up signals end-of-buffer, but c'est la vie.
  ;;
  ;; So instead of trapping a signal we instead check whether the
  ;; window begins on the first line of the buffer and if so, move
  ;; directly to that position. (We have to count lines since the
  ;; window-start position is not the same as point-min due to the
  ;; invisible thread-ID characters on the first line.
  (if (equal (count-lines (point-min) (window-start)) 0)
      (goto-char (point-min))
    (scroll-down nil)))

(defun notmuch-search-next-thread ()
  "Select the next thread in the search results."
  (interactive)
  (forward-line 1))

(defun notmuch-search-previous-thread ()
  "Select the previous thread in the search results."
  (interactive)
  (forward-line -1))

(defun notmuch-search-last-thread ()
  "Select the last thread in the search results."
  (interactive)
  (goto-char (point-max))
  (forward-line -2))

(defun notmuch-search-first-thread ()
  "Select the first thread in the search results."
  (interactive)
  (goto-char (point-min)))

(defface notmuch-message-summary-face
 '((((class color) (background light)) (:background "#f0f0f0"))
   (((class color) (background dark)) (:background "#303030")))
 "Face for the single-line message summary in notmuch-show-mode."
 :group 'notmuch-show
 :group 'notmuch-faces)

(defface notmuch-search-date
  '((t :inherit default))
  "Face used in search mode for dates."
  :group 'notmuch-search
  :group 'notmuch-faces)

(defface notmuch-search-count
  '((t :inherit default))
  "Face used in search mode for the count matching the query."
  :group 'notmuch-search
  :group 'notmuch-faces)

(defface notmuch-search-subject
  '((t :inherit default))
  "Face used in search mode for subjects."
  :group 'notmuch-search
  :group 'notmuch-faces)

(defface notmuch-search-matching-authors
  '((t :inherit default))
  "Face used in search mode for authors matching the query."
  :group 'notmuch-search
  :group 'notmuch-faces)

(defface notmuch-search-non-matching-authors
  '((((class color)
      (background dark))
     (:foreground "grey30"))
    (((class color)
      (background light))
     (:foreground "grey60"))
    (t
     (:italic t)))
  "Face used in search mode for authors not matching the query."
  :group 'notmuch-search
  :group 'notmuch-faces)

(defface notmuch-tag-face
  '((((class color)
      (background dark))
     (:foreground "OliveDrab1"))
    (((class color)
      (background light))
     (:foreground "navy blue" :bold t))
    (t
     (:bold t)))
  "Face used in search mode face for tags."
  :group 'notmuch-search
  :group 'notmuch-faces)

(defun notmuch-search-mode ()
  "Major mode displaying results of a notmuch search.

This buffer contains the results of a \"notmuch search\" of your
email archives. Each line in the buffer represents a single
thread giving a summary of the thread (a relative date, the
number of matched messages and total messages in the thread,
participants in the thread, a representative subject line, and
any tags).

Pressing \\[notmuch-search-show-thread] on any line displays that thread. The '\\[notmuch-search-add-tag]' and '\\[notmuch-search-remove-tag]'
keys can be used to add or remove tags from a thread. The '\\[notmuch-search-archive-thread]' key
is a convenience for archiving a thread (removing the \"inbox\"
tag). The '\\[notmuch-search-tag-all]' key can be used to add or remove a tag from all
threads in the current buffer.

Other useful commands are '\\[notmuch-search-filter]' for filtering the current search
based on an additional query string, '\\[notmuch-search-filter-by-tag]' for filtering to include
only messages with a given tag, and '\\[notmuch-search]' to execute a new, global
search.

Complete list of currently available key bindings:

\\{notmuch-search-mode-map}"
  (interactive)
  (kill-all-local-variables)
  (make-local-variable 'notmuch-search-query-string)
  (make-local-variable 'notmuch-search-oldest-first)
  (make-local-variable 'notmuch-search-target-thread)
  (make-local-variable 'notmuch-search-target-line)
  (set (make-local-variable 'notmuch-search-continuation) nil)
  (set (make-local-variable 'scroll-preserve-screen-position) t)
  (add-to-invisibility-spec (cons 'ellipsis t))
  (use-local-map notmuch-search-mode-map)
  (setq truncate-lines t)
  (setq major-mode 'notmuch-search-mode
	mode-name "notmuch-search")
  (setq buffer-read-only t))

(defun notmuch-search-properties-in-region (property beg end)
  (save-excursion
    (let ((output nil)
	  (last-line (line-number-at-pos end))
	  (max-line (- (line-number-at-pos (point-max)) 2)))
      (goto-char beg)
      (beginning-of-line)
      (while (<= (line-number-at-pos) (min last-line max-line))
	(setq output (cons (get-text-property (point) property) output))
	(forward-line 1))
      output)))

(defun notmuch-search-find-thread-id ()
  "Return the thread for the current thread"
  (get-text-property (point) 'notmuch-search-thread-id))

(defun notmuch-search-find-thread-id-region (beg end)
  "Return a list of threads for the current region"
  (notmuch-search-properties-in-region 'notmuch-search-thread-id beg end))

(defun notmuch-search-find-thread-id-region-search (beg end)
  "Return a search string for threads for the current region"
  (mapconcat 'identity (notmuch-search-find-thread-id-region beg end) " or "))

(defun notmuch-search-find-authors ()
  "Return the authors for the current thread"
  (get-text-property (point) 'notmuch-search-authors))

(defun notmuch-search-find-authors-region (beg end)
  "Return a list of authors for the current region"
  (notmuch-search-properties-in-region 'notmuch-search-authors beg end))

(defun notmuch-search-find-subject ()
  "Return the subject for the current thread"
  (get-text-property (point) 'notmuch-search-subject))

(defun notmuch-search-find-subject-region (beg end)
  "Return a list of authors for the current region"
  (notmuch-search-properties-in-region 'notmuch-search-subject beg end))

(defun notmuch-search-show-thread ()
  "Display the currently selected thread."
  (interactive)
  (let ((thread-id (notmuch-search-find-thread-id))
	(subject (notmuch-prettify-subject (notmuch-search-find-subject))))
    (if (> (length thread-id) 0)
	(notmuch-show thread-id
		      (current-buffer)
		      notmuch-search-query-string
		      ;; Name the buffer based on the subject.
		      (concat "*" (truncate-string-to-width subject 30 nil nil t) "*"))
      (message "End of search results."))))

(defun notmuch-search-reply-to-thread (&optional prompt-for-sender)
  "Begin composing a reply-all to the entire current thread in a new buffer."
  (interactive "P")
  (let ((message-id (notmuch-search-find-thread-id)))
    (notmuch-mua-new-reply message-id prompt-for-sender t)))

(defun notmuch-search-reply-to-thread-sender (&optional prompt-for-sender)
  "Begin composing a reply to the entire current thread in a new buffer."
  (interactive "P")
  (let ((message-id (notmuch-search-find-thread-id)))
    (notmuch-mua-new-reply message-id prompt-for-sender nil)))

(defun notmuch-call-notmuch-process (&rest args)
  "Synchronously invoke \"notmuch\" with the given list of arguments.

Output from the process will be presented to the user as an error
and will also appear in a buffer named \"*Notmuch errors*\"."
  (let ((error-buffer (get-buffer-create "*Notmuch errors*")))
    (with-current-buffer error-buffer
	(erase-buffer))
    (if (eq (apply 'call-process notmuch-command nil error-buffer nil args) 0)
	(point)
      (progn
	(with-current-buffer error-buffer
	  (let ((beg (point-min))
		(end (- (point-max) 1)))
	    (error (buffer-substring beg end))
	    ))))))

(defun notmuch-tag (query &rest tag-changes)
  "Add/remove tags in TAG-CHANGES to messages matching QUERY.

TAG-CHANGES should be a list of strings of the form \"+tag\" or
\"-tag\" and QUERY should be a string containing the
search-query.

Note: Other code should always use this function alter tags of
messages instead of running (notmuch-call-notmuch-process \"tag\" ..)
directly, so that hooks specified in notmuch-before-tag-hook and
notmuch-after-tag-hook will be run."
  ;; Perform some validation
  (mapc (lambda (tag-change)
	  (unless (string-match-p "^[-+]\\S-+$" tag-change)
	    (error "Tag must be of the form `+this_tag' or `-that_tag'")))
	tag-changes)
  (unless (null tag-changes)
    (run-hooks 'notmuch-before-tag-hook)
    (apply 'notmuch-call-notmuch-process "tag"
	   (append tag-changes (list "--" query)))
    (run-hooks 'notmuch-after-tag-hook)))

(defcustom notmuch-before-tag-hook nil
  "Hooks that are run before tags of a message are modified.

'tags' will contain the tags that are about to be added or removed as
a list of strings of the form \"+TAG\" or \"-TAG\".
'query' will be a string containing the search query that determines
the messages that are about to be tagged"

  :type 'hook
  :options '(notmuch-hl-line-mode)
  :group 'notmuch-hooks)

(defcustom notmuch-after-tag-hook nil
  "Hooks that are run after tags of a message are modified.

'tags' will contain the tags that were added or removed as
a list of strings of the form \"+TAG\" or \"-TAG\".
'query' will be a string containing the search query that determines
the messages that were tagged"
  :type 'hook
  :options '(notmuch-hl-line-mode)
  :group 'notmuch-hooks)

(defun notmuch-search-set-tags (tags)
  (save-excursion
    (end-of-line)
    (re-search-backward "(")
    (forward-char)
    (let ((beg (point))
	  (inhibit-read-only t))
      (re-search-forward ")")
      (backward-char)
      (let ((end (point)))
	(delete-region beg end)
	(insert (propertize (mapconcat  'identity tags " ")
			    'face 'notmuch-tag-face))))))

(defun notmuch-search-get-tags ()
  (save-excursion
    (end-of-line)
    (re-search-backward "(")
    (let ((beg (+ (point) 1)))
      (re-search-forward ")")
      (let ((end (- (point) 1)))
	(split-string (buffer-substring-no-properties beg end))))))

(defun notmuch-search-get-tags-region (beg end)
  (save-excursion
    (let ((output nil)
	  (last-line (line-number-at-pos end))
	  (max-line (- (line-number-at-pos (point-max)) 2)))
      (goto-char beg)
      (while (<= (line-number-at-pos) (min last-line max-line))
	(setq output (append output (notmuch-search-get-tags)))
	(forward-line 1))
      output)))

(defun notmuch-search-tag-thread (&rest tag-changes)
  "Change tags for the currently selected thread.

See `notmuch-search-tag-region' for details."
  (apply 'notmuch-search-tag-region (point) (point) tag-changes))

(defun notmuch-search-tag-region (beg end &rest tag-changes)
  "Change tags for threads in the given region.

TAGS is a list of tag operations for `notmuch-tag'.  The tags are
added or removed for all threads in the region from BEG to END."
  (let ((search-string (notmuch-search-find-thread-id-region-search beg end)))
    (apply 'notmuch-tag search-string tag-changes)
    (save-excursion
      (let ((last-line (line-number-at-pos end))
	    (max-line (- (line-number-at-pos (point-max)) 2)))
	(goto-char beg)
	(while (<= (line-number-at-pos) (min last-line max-line))
	  (notmuch-search-set-tags
	   (notmuch-update-tags (notmuch-search-get-tags) tag-changes))
	  (forward-line))))))

(defun notmuch-search-tag (&optional initial-input)
  "Change tags for the currently selected thread or region."
  (interactive)
  (let* ((beg (if (region-active-p) (region-beginning) (point)))
	 (end (if (region-active-p) (region-end) (point)))
	 (search-string (notmuch-search-find-thread-id-region-search beg end))
	 (tags (notmuch-read-tag-changes initial-input search-string)))
    (apply 'notmuch-search-tag-region beg end tags)))

(defun notmuch-search-add-tag ()
  "Same as `notmuch-search-tag' but sets initial input to '+'."
  (interactive)
  (notmuch-search-tag "+"))

(defun notmuch-search-remove-tag ()
  "Same as `notmuch-search-tag' but sets initial input to '-'."
  (interactive)
  (notmuch-search-tag "-"))

(defun notmuch-search-tag-and-advance (&rest tags)
  "Apply a tag or set of tags to the current thread.

Shortcut to simplify applying tags in search mode. Targeted for
use in key-bound functions. Advances to the next thread after
applying the tags."
  (mapc 'notmuch-search-tag-thread tags)
  (notmuch-search-next-thread))

(defun notmuch-search-archive-thread ()
  "Archive the currently selected thread (remove its \"inbox\" tag).

This function advances the next thread when finished."
  (interactive)
  (notmuch-search-tag-thread "-inbox")
  (notmuch-search-next-thread))

(defvar notmuch-search-process-filter-data nil
  "Data that has not yet been processed.")
(make-variable-buffer-local 'notmuch-search-process-filter-data)

(defun notmuch-search-process-sentinel (proc msg)
  "Add a message to let user know when \"notmuch search\" exits"
  (let ((buffer (process-buffer proc))
	(status (process-status proc))
	(exit-status (process-exit-status proc))
	(never-found-target-thread nil))
    (if (memq status '(exit signal))
	(if (buffer-live-p buffer)
	    (with-current-buffer buffer
	      (save-excursion
		(let ((inhibit-read-only t)
		      (atbob (bobp)))
		  (goto-char (point-max))
		  (if (eq status 'signal)
		      (insert "Incomplete search results (search process was killed).\n"))
		  (when (eq status 'exit)
		    (if notmuch-search-process-filter-data
			(insert (concat "Error: Unexpected output from notmuch search:\n" notmuch-search-process-filter-data)))
		    (insert "End of search results.")
		    (unless (= exit-status 0)
		      (insert (format " (process returned %d)" exit-status)))
		    (insert "\n")
		    (if (and atbob
			     (not (string= notmuch-search-target-thread "found")))
			(set 'never-found-target-thread t)))))
	      (when (and never-found-target-thread
		       notmuch-search-target-line)
		  (goto-char (point-min))
		  (forward-line (1- notmuch-search-target-line))))))))

(defcustom notmuch-search-line-faces '(("unread" :weight bold)
				       ("flagged" :foreground "blue"))
  "Tag/face mapping for line highlighting in notmuch-search.

Here is an example of how to color search results based on tags.
 (the following text would be placed in your ~/.emacs file):

 (setq notmuch-search-line-faces '((\"delete\" . (:foreground \"red\"
						  :background \"blue\"))
                                   (\"unread\" . (:foreground \"green\"))))

The attributes defined for matching tags are merged, with later
attributes overriding earlier. A message having both \"delete\"
and \"unread\" tags with the above settings would have a green
foreground and blue background."
  :type '(alist :key-type (string) :value-type (custom-face-edit))
  :group 'notmuch-search
  :group 'notmuch-faces)

(defun notmuch-search-color-line (start end line-tag-list)
  "Colorize lines in `notmuch-show' based on tags."
  ;; Create the overlay only if the message has tags which match one
  ;; of those specified in `notmuch-search-line-faces'.
  (let (overlay)
    (mapc (lambda (elem)
	    (let ((tag (car elem))
		  (attributes (cdr elem)))
	      (when (member tag line-tag-list)
		(when (not overlay)
		  (setq overlay (make-overlay start end)))
		;; Merge the specified properties with any already
		;; applied from an earlier match.
		(overlay-put overlay 'face
			     (append (overlay-get overlay 'face) attributes)))))
	  notmuch-search-line-faces)))

(defun notmuch-search-author-propertize (authors)
  "Split `authors' into matching and non-matching authors and
propertize appropriately. If no boundary between authors and
non-authors is found, assume that all of the authors match."
  (if (string-match "\\(.*\\)|\\(.*\\)" authors)
      (concat (propertize (concat (match-string 1 authors) ",")
			  'face 'notmuch-search-matching-authors)
	      (propertize (match-string 2 authors)
			  'face 'notmuch-search-non-matching-authors))
    (propertize authors 'face 'notmuch-search-matching-authors)))

(defun notmuch-search-insert-authors (format-string authors)
  ;; Save the match data to avoid interfering with
  ;; `notmuch-search-process-filter'.
  (save-match-data
    (let* ((formatted-authors (format format-string authors))
	   (formatted-sample (format format-string ""))
	   (visible-string formatted-authors)
	   (invisible-string "")
	   (padding ""))

      ;; Truncate the author string to fit the specification.
      (if (> (length formatted-authors)
	     (length formatted-sample))
	  (let ((visible-length (- (length formatted-sample)
				   (length "... "))))
	    ;; Truncate the visible string according to the width of
	    ;; the display string.
	    (setq visible-string (substring formatted-authors 0 visible-length)
		  invisible-string (substring formatted-authors visible-length))
	    ;; If possible, truncate the visible string at a natural
	    ;; break (comma or pipe), as incremental search doesn't
	    ;; match across the visible/invisible border.
	    (when (string-match "\\(.*\\)\\([,|] \\)\\([^,|]*\\)" visible-string)
	      ;; Second clause is destructive on `visible-string', so
	      ;; order is important.
	      (setq invisible-string (concat (match-string 3 visible-string)
					     invisible-string)
		    visible-string (concat (match-string 1 visible-string)
					   (match-string 2 visible-string))))
	    ;; `visible-string' may be shorter than the space allowed
	    ;; by `format-string'. If so we must insert some padding
	    ;; after `invisible-string'.
	    (setq padding (make-string (- (length formatted-sample)
					  (length visible-string)
					  (length "..."))
				       ? ))))

      ;; Use different faces to show matching and non-matching authors.
      (if (string-match "\\(.*\\)|\\(.*\\)" visible-string)
	  ;; The visible string contains both matching and
	  ;; non-matching authors.
	  (setq visible-string (notmuch-search-author-propertize visible-string)
		;; The invisible string must contain only non-matching
		;; authors, as the visible-string contains both.
		invisible-string (propertize invisible-string
					     'face 'notmuch-search-non-matching-authors))
	;; The visible string contains only matching authors.
	(setq visible-string (propertize visible-string
					 'face 'notmuch-search-matching-authors)
	      ;; The invisible string may contain both matching and
	      ;; non-matching authors.
	      invisible-string (notmuch-search-author-propertize invisible-string)))

      ;; If there is any invisible text, add it as a tooltip to the
      ;; visible text.
      (when (not (string= invisible-string ""))
	(setq visible-string (propertize visible-string 'help-echo (concat "..." invisible-string))))

      ;; Insert the visible and, if present, invisible author strings.
      (insert visible-string)
      (when (not (string= invisible-string ""))
	(let ((start (point))
	      overlay)
	  (insert invisible-string)
	  (setq overlay (make-overlay start (point)))
	  (overlay-put overlay 'invisible 'ellipsis)
	  (overlay-put overlay 'isearch-open-invisible #'delete-overlay)))
      (insert padding))))

(defun notmuch-search-insert-field (field date count authors subject tags)
  (cond
   ((string-equal field "date")
    (insert (propertize (format (cdr (assoc field notmuch-search-result-format)) date)
			'face 'notmuch-search-date)))
   ((string-equal field "count")
    (insert (propertize (format (cdr (assoc field notmuch-search-result-format)) count)
			'face 'notmuch-search-count)))
   ((string-equal field "subject")
    (insert (propertize (format (cdr (assoc field notmuch-search-result-format)) subject)
			'face 'notmuch-search-subject)))

   ((string-equal field "authors")
    (notmuch-search-insert-authors (cdr (assoc field notmuch-search-result-format)) authors))

   ((string-equal field "tags")
    (insert (concat "(" (propertize tags 'font-lock-face 'notmuch-tag-face) ")")))))

(defun notmuch-search-show-result (date count authors subject tags)
  (let ((fields) (field))
    (setq fields (mapcar 'car notmuch-search-result-format))
    (loop for field in fields
	  do (notmuch-search-insert-field field date count authors subject tags)))
  (insert "\n"))

(defun notmuch-search-process-filter (proc string)
  "Process and filter the output of \"notmuch search\""
  (let ((buffer (process-buffer proc))
	(found-target nil))
    (if (buffer-live-p buffer)
	(with-current-buffer buffer
	  (save-excursion
	    (let ((line 0)
		  (more t)
		  (inhibit-read-only t)
		  (string (concat notmuch-search-process-filter-data string)))
	      (setq notmuch-search-process-filter-data nil)
	      (while more
		(while (and (< line (length string)) (= (elt string line) ?\n))
		  (setq line (1+ line)))
		(if (string-match "^\\(thread:[0-9A-Fa-f]*\\) \\([^][]*\\) \\(\\[[0-9/]*\\]\\) \\([^;]*\\); \\(.*\\) (\\([^()]*\\))$" string line)
		    (let* ((thread-id (match-string 1 string))
			   (date (match-string 2 string))
			   (count (match-string 3 string))
			   (authors (match-string 4 string))
			   (subject (match-string 5 string))
			   (tags (match-string 6 string))
			   (tag-list (if tags (save-match-data (split-string tags)))))
		      (goto-char (point-max))
		      (if (/= (match-beginning 1) line)
			  (insert (concat "Error: Unexpected output from notmuch search:\n" (substring string line (match-beginning 1)) "\n")))
		      ;; We currently just throw away excluded matches.
		      (unless (eq (aref count 1) ?0)
			(let ((beg (point)))
			  (notmuch-search-show-result date count authors
						      (notmuch-prettify-subject subject) tags)
			  (notmuch-search-color-line beg (point) tag-list)
			  (put-text-property beg (point) 'notmuch-search-thread-id thread-id)
			  (put-text-property beg (point) 'notmuch-search-authors authors)
			  (put-text-property beg (point) 'notmuch-search-subject subject)
			  (when (string= thread-id notmuch-search-target-thread)
			    (set 'found-target beg)
			    (set 'notmuch-search-target-thread "found"))))
		      (set 'line (match-end 0)))
		  (set 'more nil)
		  (while (and (< line (length string)) (= (elt string line) ?\n))
		    (setq line (1+ line)))
		  (if (< line (length string))
		      (setq notmuch-search-process-filter-data (substring string line)))
		  ))))
	  (if found-target
	      (goto-char found-target)))
      (delete-process proc))))

(defun notmuch-search-tag-all (&rest tag-changes)
  "Add/remove tags from all matching messages.

This command adds or removes tags from all messages matching the
current search terms. When called interactively, this command
will prompt for tags to be added or removed. Tags prefixed with
'+' will be added and tags prefixed with '-' will be removed.

Each character of the tag name may consist of alphanumeric
characters as well as `_.+-'.
"
  (interactive (notmuch-read-tag-changes))
  (apply 'notmuch-tag notmuch-search-query-string tag-changes))

(defun notmuch-search-buffer-title (query)
  "Returns the title for a buffer with notmuch search results."
  (let* ((saved-search
	  (let (longest
		(longest-length 0))
	    (loop for tuple in notmuch-saved-searches
		  if (let ((quoted-query (regexp-quote (cdr tuple))))
		       (and (string-match (concat "^" quoted-query) query)
			    (> (length (match-string 0 query))
			       longest-length)))
		  do (setq longest tuple))
	    longest))
	 (saved-search-name (car saved-search))
	 (saved-search-query (cdr saved-search)))
    (cond ((and saved-search (equal saved-search-query query))
	   ;; Query is the same as saved search (ignoring case)
	   (concat "*notmuch-saved-search-" saved-search-name "*"))
	  (saved-search
	   (concat "*notmuch-search-"
		   (replace-regexp-in-string (concat "^" (regexp-quote saved-search-query))
					     (concat "[ " saved-search-name " ]")
					     query)
		   "*"))
	  (t
	   (concat "*notmuch-search-" query "*"))
	  )))

(defun notmuch-read-query (prompt)
  "Read a notmuch-query from the minibuffer with completion.

PROMPT is the string to prompt with."
  (lexical-let
      ((completions
	(append (list "folder:" "thread:" "id:" "date:" "from:" "to:"
		      "subject:" "attachment:")
		(mapcar (lambda (tag)
			  (concat "tag:" tag))
			(process-lines notmuch-command "search" "--output=tags" "*")))))
    (let ((keymap (copy-keymap minibuffer-local-map))
	  (minibuffer-completion-table
	   (completion-table-dynamic
	    (lambda (string)
	      ;; generate a list of possible completions for the current input
	      (cond
	       ;; this ugly regexp is used to get the last word of the input
	       ;; possibly preceded by a '('
	       ((string-match "\\(^\\|.* (?\\)\\([^ ]*\\)$" string)
		(mapcar (lambda (compl)
			  (concat (match-string-no-properties 1 string) compl))
			(all-completions (match-string-no-properties 2 string)
					 completions)))
	       (t (list string)))))))
      ;; this was simpler than convincing completing-read to accept spaces:
      (define-key keymap (kbd "<tab>") 'minibuffer-complete)
      (let ((history-delete-duplicates t))
	(read-from-minibuffer prompt nil keymap nil
			      'notmuch-search-history nil nil)))))

;;;###autoload
(defun notmuch-search (&optional query oldest-first target-thread target-line continuation)
  "Run \"notmuch search\" with the given `query' and display results.

If `query' is nil, it is read interactively from the minibuffer.
Other optional parameters are used as follows:

  oldest-first: A Boolean controlling the sort order of returned threads
  target-thread: A thread ID (with the thread: prefix) that will be made
                 current if it appears in the search results.
  target-line: The line number to move to if the target thread does not
               appear in the search results."
  (interactive)
  (if (null query)
      (setq query (notmuch-read-query "Notmuch search: ")))
  (let ((buffer (get-buffer-create (notmuch-search-buffer-title query))))
    (switch-to-buffer buffer)
    (notmuch-search-mode)
    ;; Don't track undo information for this buffer
    (set 'buffer-undo-list t)
    (set 'notmuch-search-query-string query)
    (set 'notmuch-search-oldest-first oldest-first)
    (set 'notmuch-search-target-thread target-thread)
    (set 'notmuch-search-target-line target-line)
    (set 'notmuch-search-continuation continuation)
    (let ((proc (get-buffer-process (current-buffer)))
	  (inhibit-read-only t))
      (if proc
	  (error "notmuch search process already running for query `%s'" query)
	)
      (erase-buffer)
      (goto-char (point-min))
      (save-excursion
	(let ((proc (start-process
		     "notmuch-search" buffer
		     notmuch-command "search"
		     (if oldest-first
			 "--sort=oldest-first"
		       "--sort=newest-first")
		     query)))
	  (set-process-sentinel proc 'notmuch-search-process-sentinel)
	  (set-process-filter proc 'notmuch-search-process-filter)
	  (set-process-query-on-exit-flag proc nil))))
    (run-hooks 'notmuch-search-hook)))

(defun notmuch-search-refresh-view ()
  "Refresh the current view.

Kills the current buffer and runs a new search with the same
query string as the current search. If the current thread is in
the new search results, then point will be placed on the same
thread. Otherwise, point will be moved to attempt to be in the
same relative position within the new buffer."
  (interactive)
  (let ((target-line (line-number-at-pos))
	(oldest-first notmuch-search-oldest-first)
	(target-thread (notmuch-search-find-thread-id))
	(query notmuch-search-query-string)
	(continuation notmuch-search-continuation))
    (notmuch-kill-this-buffer)
    (notmuch-search query oldest-first target-thread target-line continuation)
    (goto-char (point-min))))

(defcustom notmuch-poll-script nil
  "An external script to incorporate new mail into the notmuch database.

This variable controls the action invoked by
`notmuch-search-poll-and-refresh-view' and
`notmuch-hello-poll-and-update' (each have a default keybinding
of 'G') to incorporate new mail into the notmuch database.

If set to nil (the default), new mail is processed by invoking
\"notmuch new\". Otherwise, this should be set to a string that
gives the name of an external script that processes new mail. If
set to the empty string, no command will be run.

The external script could do any of the following depending on
the user's needs:

1. Invoke a program to transfer mail to the local mail store
2. Invoke \"notmuch new\" to incorporate the new mail
3. Invoke one or more \"notmuch tag\" commands to classify the mail

Note that the recommended way of achieving the same is using
\"notmuch new\" hooks."
  :type '(choice (const :tag "notmuch new" nil)
		 (const :tag "Disabled" "")
		 (string :tag "Custom script"))
  :group 'notmuch-external)

(defun notmuch-poll ()
  "Run \"notmuch new\" or an external script to import mail.

Invokes `notmuch-poll-script', \"notmuch new\", or does nothing
depending on the value of `notmuch-poll-script'."
  (interactive)
  (if (stringp notmuch-poll-script)
      (unless (string= notmuch-poll-script "")
	(call-process notmuch-poll-script nil nil))
    (call-process notmuch-command nil nil nil "new")))

(defun notmuch-search-poll-and-refresh-view ()
  "Invoke `notmuch-poll' to import mail, then refresh the current view."
  (interactive)
  (notmuch-poll)
  (notmuch-search-refresh-view))

(defun notmuch-search-toggle-order ()
  "Toggle the current search order.

By default, the \"inbox\" view created by `notmuch' is displayed
in chronological order (oldest thread at the beginning of the
buffer), while any global searches created by `notmuch-search'
are displayed in reverse-chronological order (newest thread at
the beginning of the buffer).

This command toggles the sort order for the current search.

Note that any filtered searches created by
`notmuch-search-filter' retain the search order of the parent
search."
  (interactive)
  (set 'notmuch-search-oldest-first (not notmuch-search-oldest-first))
  (notmuch-search-refresh-view))

(defun notmuch-search-filter (query)
  "Filter the current search results based on an additional query string.

Runs a new search matching only messages that match both the
current search results AND the additional query string provided."
  (interactive (list (notmuch-read-query "Filter search: ")))
  (let ((grouped-query (if (string-match-p notmuch-search-disjunctive-regexp query)
			   (concat "( " query " )")
			 query)))
    (notmuch-search (if (string= notmuch-search-query-string "*")
			grouped-query
		      (concat notmuch-search-query-string " and " grouped-query)) notmuch-search-oldest-first)))

(defun notmuch-search-filter-by-tag (tag)
  "Filter the current search results based on a single tag.

Runs a new search matching only messages that match both the
current search results AND that are tagged with the given tag."
  (interactive
   (list (notmuch-select-tag-with-completion "Filter by tag: ")))
  (notmuch-search (concat notmuch-search-query-string " and tag:" tag) notmuch-search-oldest-first))

;;;###autoload
(defun notmuch ()
  "Run notmuch and display saved searches, known tags, etc."
  (interactive)
  (notmuch-hello))

(defun notmuch-interesting-buffer (b)
  "Is the current buffer of interest to a notmuch user?"
  (with-current-buffer b
    (memq major-mode '(notmuch-show-mode
		       notmuch-search-mode
		       notmuch-hello-mode
		       message-mode))))

;;;###autoload
(defun notmuch-cycle-notmuch-buffers ()
  "Cycle through any existing notmuch buffers (search, show or hello).

If the current buffer is the only notmuch buffer, bury it. If no
notmuch buffers exist, run `notmuch'."
  (interactive)

  (let (start first)
    ;; If the current buffer is a notmuch buffer, remember it and then
    ;; bury it.
    (when (notmuch-interesting-buffer (current-buffer))
      (setq start (current-buffer))
      (bury-buffer))

    ;; Find the first notmuch buffer.
    (setq first (loop for buffer in (buffer-list)
		     if (notmuch-interesting-buffer buffer)
		     return buffer))

    (if first
	;; If the first one we found is any other than the starting
	;; buffer, switch to it.
	(unless (eq first start)
	  (switch-to-buffer first))
      (notmuch))))

(setq mail-user-agent 'notmuch-user-agent)

(provide 'notmuch)