;;; nnnm.el --- Gnus backend for notmuch -*- lexical-binding: t; -*-
;; Copyright (C) 2021 jao
;; Author: jao <mail@jao.io>
;; Keywords: mail
;; This program 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.
;; This program 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 this program. If not, see <https://www.gnu.org/licenses/>.
;;; Commentary:
;; A Gnus mail backend using notmuch.
;;; Code:
(require 'gnus)
(require 'nnheader)
(require 'nnmail)
(require 'nnoo)
(nnoo-declare nnnm)
(defvar nnnm-marks-to-tags '((tick . "flagged")))
(defvar nnnm-saved-searches nil)
(defvar nnnm-maildir nil)
(defvar nnnm--group-data nil)
(defun nnnm--group-data (group) (cdr (assoc group nnnm--group-data)))
(defun nnnm--set-group-data (group data)
(setf (alist-get group nnnm--group-data nil t #'string=) data))
(defun nnnm--find-query (name)
(when-let (s (seq-find (lambda (s) (string= (plist-get s :name) name))
nnnm-saved-searches))
(plist-get s :query)))
(defun nnnm--find-message-file (id)
(car (split-string
(shell-command-to-string
(format "notmuch search --output=files %s"
(if (string-prefix-p "id:" id) id (concat "id:" id)))))))
(defun nnnm--article-data (article group)
(cond ((stringp article) (list article))
((numberp article)
(when-let (data (nnnm--group-data group))
(elt data (1- article))))))
(defun nnnm-article-to-file (article group)
(when-let (d (nnnm--article-data article group))
(or (cadr d) (nnnm--find-message-file (car d)))))
(defun nnnm--count (query &optional context)
(let ((cmd (format "notmuch count -- '(%s)%s'"
query
(if context (concat " AND " context) ""))))
(string-to-number (shell-command-to-string cmd))))
(defun nnnm--search (query &optional context)
(let ((cmd (format "notmuch search --sort=oldest-first --output=messages -- %s%s"
(shell-quote-argument (format "(%s)" query))
(if context (concat " AND " context) ""))))
(split-string (shell-command-to-string cmd))))
(defun nnnm--tag (query tags)
(let ((cmd (format "notmuch tag %s -- '(%s)'" tags query)))
(shell-command-to-string cmd)))
(defun nnnm--ids-query (ids) (mapconcat #'identity ids " OR "))
(defun nnnm--prefixed (group server)
(gnus-group-prefixed-name group `(nnnm ,server)))
(defun nnnm--get-group-marks (group server)
(gnus-info-marks (gnus-get-info (nnnm--prefixed group server))))
(defun nnnm--set-group-marks (marks group server)
(let* ((full-group (nnnm--prefixed group server))
(info (gnus-get-info full-group)))
(gnus-info-set-marks info marks)
(gnus-set-info full-group info)))
(defun nnnm--subtract-from-ranges (ranges lst)
(let ((ranges (gnus-uncompress-sequence ranges)))
(dolist (n lst)
(let ((rs (seq-group-by (lambda (r) (> n r)) ranges)))
(setq ranges
(append (alist-get t rs) (mapcar #'1- (alist-get nil rs))))))
(gnus-compress-sequence ranges)))
(defun nnnm--remove-articles-from-marks (ranges group server)
(let ((marks (nnnm--get-group-marks group server))
(lst (gnus-uncompress-sequence ranges))
(new-marks))
(dolist (m marks)
(push (cons (car m) (nnnm--subtract-from-ranges (cdr m))) lst))
(nnnm--set-group-marks marks group server)))
(defun nnnm--set-active (n group server)
(gnus-set-active (nnnm--prefixed group server) (cons 1 n)))
(defun nnnm--update-group-data (group &optional server)
(when-let (query (nnnm--find-query group))
(let* ((data (or (nnnm--group-data group)
(mapcar #'list (nnnm--search query "NOT tag:new"))))
(ids (nnnm--search query "tag:new"))
(nids (length ids))
(new-data (mapcar (lambda (id)
(list id (nnnm--find-message-file id)))
ids)))
(when (> nids 0)
(nnnm--tag (nnnm--ids-query ids) "-new")
(nnheader-report 'nnnm "%s: %d new messages retrieved" group nids))
(nnnm--set-group-data group (append data new-data))
(nnnm--set-active (+ nids (length data)) group server)
(length ids))))
;;; Interface functions.
(nnoo-define-basics nnnm)
(defun nnnm-request-type (_group &optional _article)
'mail)
(deffoo nnnm-open-server (server &optional defs)
(nnoo-change-server 'nnnm server defs)
(setq nnnm--group-data nil)
(nnheader-report 'nnnm "Opened server %s" server)
t)
(deffoo nnnm-close-server (_server)
(setq nnnm--group-data nil))
(deffoo nnnm-request-regenerate (_server)
(setq nnnm--group-data nil)
t)
(deffoo nnnm-request-list (&optional _server)
(with-current-buffer nntp-server-buffer
(erase-buffer)
(dolist (s nnnm-saved-searches)
(when-let (query (plist-get s :query))
(let ((name (plist-get s :name))
(total (nnnm--count query)))
(insert (format "%s %d 1 y\n" name total))))))
t)
(deffoo nnnm-retrieve-headers (sequence &optional group server _fetch-old)
(when (nnnm--update-group-data group server)
(with-current-buffer nntp-server-buffer
(delete-region (point-min) (point-max))
(let ((file-name-coding-system nnmail-pathname-coding-system)
(count -1))
(if (stringp (car sequence))
'headers
(dolist (article sequence)
(when-let (file (nnnm-article-to-file article group))
(insert (format "221 %d Article retrieved.\n" article))
(save-excursion (nnheader-insert-head file))
(if (re-search-forward "\n\r?\n" nil t)
(forward-char -1)
(goto-char (point-max))
(insert "\n\n"))
(insert ".\n")
(delete-region (point) (point-max)))
(when (zerop (% (cl-incf count) 20))
(nnheader-message 6 "nnnm: Receiving headers... %d%%"
(floor (* count 100.0) (length sequence)))))
(nnheader-fold-continuation-lines)
'headers)))))
(deffoo nnnm-request-article (id &optional group _server buffer)
(let* ((nntp-server-buffer (or buffer nntp-server-buffer))
(file-name-coding-system nnmail-pathname-coding-system)
(d (nnnm--article-data id group))
(id (car d))
(file (when id (or (cadr d) (nnnm--find-message-file id)))))
(cond
((not file)
(nnheader-report 'nnnm "No such article: %s" id))
((not (file-exists-p file))
(nnheader-report 'nnnm "No such file: %s" file))
((not (save-excursion (nnmail-find-file file)))
(nnheader-report 'nnnm "Couldn't read file: %s" file))
(t
(nnnm--tag id "-unread")
(nnheader-report 'nnnm "Article %s retrieved and tagged" id)
(cons group id)))))
(deffoo nnnm-request-expire-articles (articles group &optional _server _force)
(let* ((articles (gnus-uncompress-range articles))
(ids (mapcar (lambda (a) (car (nnnm--article-data a group))) articles)))
(when ids
(nnnm--tag (nnnm--ids-query ids) "+deleted")
(let ((data (nnnm--group-data group)))
(dolist (id ids)
(setq data
(cl-delete-if (lambda (d) (string= (car d) id)) data :count 1)))
(nnnm--set-group-data group data)
(nnnm--remove-articles-from-marks articles group server)
(nnnm--set-active (length data) group server)))
articles))
(deffoo nnnm-request-set-mark (group actions &optional _server)
(message "set marks: %s: %S" group actions)
actions)
;; (deffoo nnnm-request-move-article
;; (article group server accept-form &optional last _move-is-internal)
;; (error "Not implemented yet"))
(deffoo nnnm-request-group (group &optional server _dont-check info)
(nnheader-message 7 "nnnm: Opening %s -- %s" info group)
(if (nnnm--update-group-data group server)
(let ((n (length (nnnm--group-data group))))
(with-current-buffer nntp-server-buffer
(erase-buffer)
(nnheader-insert "211 %d %d %d %s\n" n 1 n group)
n))
(nnheader-report 'nnnm "Invalid group")))
(deffoo nnnm-request-newgroups (_date &optional server)
(nnnm-request-list server))
(deffoo nnnm-request-group-scan (group &optional server _info)
(nnnm--set-group-data group nil)
(nnnm--update-group-data group server))
(deffoo nnnm-request-scan (&optional group server)
(if group
(nnnm--update-group-data group server)
(setq nnnm--group-data nil)))
(deffoo nnnm-request-create-group (group &optional _server _args)
(let ((query (read-string "Query: ")))
(add-to-list 'nnnm-saved-searches `(:name ,group :query ,query))))
;; (deffoo nnnm-request-rename-group (group new-name &optional _server)
;; (error "Not implemented yet"))
(deffoo nnnm-close-group (_group &optional _server) t)
(provide 'nnnm)
;;; nnnm.el ends here