(require 'notmuch-message)

(defun ambrevar/org-notmuch-get (field &optional name)
  "Return list of emails from FIELD ready for Org capture.
With NAME, return name instead."
  (when field
    (mapconcat (if name #'car #'cadr) (mail-extract-address-components field 'all) "|")))

;; TODO: Report org-notmuch-store-link upstream.
(defun org-notmuch-store-link ()
  "Store a link to a notmuch search or message."
  (when (or (eq major-mode 'notmuch-show-mode)
            (eq major-mode 'notmuch-tree-mode))
    (let* ((message-id (notmuch-show-get-message-id t))
           (subject (notmuch-show-get-subject))
           (to (notmuch-show-get-to))
           (cc (notmuch-show-get-cc))
           (from (notmuch-show-get-from))
           (date (org-trim (notmuch-show-get-date)))
           desc link)
      (org-store-link-props :type "notmuch" :from from :to to :date date
                            :subject subject :message-id message-id
                            :to-names (ambrevar/org-notmuch-get to 'name)
                            :to-addresses (ambrevar/org-notmuch-get to)
                            :cc-names (ambrevar/org-notmuch-get cc 'name)
                            :cc-addresses (ambrevar/org-notmuch-get cc))
      (setq desc (org-email-link-description))
      (setq link (concat "notmuch:id:" message-id))
      (org-add-link-props :link link :description desc)
      link)))

;; From https://notmuchmail.org/pipermail/notmuch/2018/026423.html

;; attachment checks
;;
;; should be sent upstream, but needs unit tests in test/T310-emacs.sh
(defcustom notmuch-message-attach-regex
  "\\b\\(attache\?ment\\|attached\\|attach\\|pi[èe]ce\s+jointe?\\)\\b"
  "Pattern of text announcing there should be an attachment.

This is used by `notmuch-message-check-attach' to check email
bodies for words that might indicate the email should have an
attachement. If the pattern matches and there is no attachment (a
`<#part ...>' magic block), notmuch will show a confirmation
prompt before sending the email.

The default regular expression is deliberately liberal: we prefer
false positive than forgotten attachments. This should be
customized for non-english languages and notmuch welcomes
additions to the pattern for your native language, unless it
conflicts with common words in other languages."
  :type '(regexp)
  :group 'notmuch-send)

(defun notmuch-message-check-attach ()
  """Check for missing attachments.

This is normally added to `message-send-hook' and is configured
through `notmuch-message-attach-regex'."""
  (save-excursion ;; XXX: this fails somehow: point is at the end of the buffer on error
    (goto-char (point-min))
    (if (re-search-forward notmuch-message-attach-regex nil t)
        (progn
          (goto-char (point-min))
          (unless (re-search-forward "<#part [^>]*filename=[^>]*>" nil t)
            (or (y-or-n-p "Email seem to refer to attachment, but nothing attached, send anyways?")
                (error "No attachment found, aborting")))))))

(add-hook 'message-send-hook 'notmuch-message-check-attach)

(provide 'patch-notmuch)