+If the Fcc header is already set, then keep it as-is.
+Otherwise set it according to `notmuch-fcc-dirs'."
+ (let ((subdir
+ (cond
+ ((or (not notmuch-fcc-dirs)
+ (message-field-value "Fcc"))
+ ;; Nothing set or an existing header.
+ nil)
+ ((stringp notmuch-fcc-dirs)
+ notmuch-fcc-dirs)
+ ((and (listp notmuch-fcc-dirs)
+ (stringp (car notmuch-fcc-dirs)))
+ ;; Old style - no longer works.
+ (error "Invalid `notmuch-fcc-dirs' setting (old style)"))
+ ((listp notmuch-fcc-dirs)
+ (if-let ((match (seq-some (let ((from (message-field-value "From")))
+ (pcase-lambda (`(,regexp . ,folder))
+ (and (string-match-p regexp from)
+ (cons t folder))))
+ notmuch-fcc-dirs)))
+ (cdr match)
+ (message "No Fcc header added.")
+ nil))
+ (t
+ (error "Invalid `notmuch-fcc-dirs' setting (neither string nor list)")))))
+ (when subdir
+ (if notmuch-maildir-use-notmuch-insert
+ (notmuch-maildir-add-notmuch-insert-style-fcc-header subdir)
+ (notmuch-maildir-add-file-style-fcc-header subdir)))))
+
+(defun notmuch-maildir-add-notmuch-insert-style-fcc-header (subdir)
+ ;; Notmuch insert does not accept absolute paths, so check the user
+ ;; really want this header inserted.
+ (when (or (not (= (elt subdir 0) ?/))
+ (y-or-n-p (format "Fcc header %s is an absolute path %s %s" subdir
+ "and notmuch insert is requested."
+ "Insert header anyway? ")))
+ (message-add-header (concat "Fcc: " subdir))))
+
+(defun notmuch-maildir-add-file-style-fcc-header (subdir)
+ (message-add-header
+ (concat "Fcc: "
+ (file-truename
+ ;; If the resulting directory is not an absolute path,
+ ;; prepend the standard notmuch database path.
+ (if (= (elt subdir 0) ?/)
+ subdir
+ (concat (notmuch-database-path) "/" subdir))))))
+
+;;; Functions for saving a message using either method.
+
+(defmacro with-temporary-notmuch-message-buffer (&rest body)
+ "Set-up a temporary copy of the current message-mode buffer."
+ `(let ((case-fold-search t)
+ (buf (current-buffer))
+ (mml-externalize-attachments message-fcc-externalize-attachments))
+ (with-current-buffer (get-buffer-create " *message temp*")
+ (message-clone-locals buf) ;; for message-encoded-mail-cache
+ (erase-buffer)
+ (insert-buffer-substring buf)
+ ,@body)))
+
+(defun notmuch-maildir-setup-message-for-saving ()
+ "Setup message for saving.
+
+This should be called on a temporary copy.
+This is taken from the function message-do-fcc."
+ (if (not message-encoded-mail-cache)
+ (message-encode-message-body)
+ (erase-buffer)
+ (insert message-encoded-mail-cache))
+ (save-restriction
+ (message-narrow-to-headers)
+ (mail-encode-encoded-word-buffer))
+ (goto-char (point-min))
+ (when (re-search-forward
+ (concat "^" (regexp-quote mail-header-separator) "$")
+ nil t)
+ (replace-match "" t t )))
+
+(defun notmuch-maildir-message-do-fcc ()
+ "Process Fcc headers in the current buffer.
+
+This is a rearranged version of message mode's message-do-fcc."
+ (let (files file)
+ (save-excursion
+ (save-restriction
+ (message-narrow-to-headers)
+ (setq file (message-fetch-field "fcc" t)))
+ (when file
+ (with-temporary-notmuch-message-buffer
+ (notmuch-maildir-setup-message-for-saving)
+ (save-restriction
+ (message-narrow-to-headers)
+ (while (setq file (message-fetch-field "fcc" t))
+ (push file files)
+ (message-remove-header "fcc" nil t)))
+ ;; Process FCC operations.
+ (mapc #'notmuch-fcc-handler files)
+ (kill-buffer (current-buffer)))))))
+
+(defun notmuch-fcc-handler (fcc-header)
+ "Store message with notmuch insert or normal (file) fcc.
+
+If `notmuch-maildir-use-notmuch-insert' is set then store the
+message using notmuch insert. Otherwise store the message using
+normal fcc."
+ (message "Doing Fcc...")
+ (if notmuch-maildir-use-notmuch-insert
+ (notmuch-maildir-fcc-with-notmuch-insert fcc-header)
+ (notmuch-maildir-fcc-file-fcc fcc-header))
+ (message "Doing Fcc...done"))
+
+;;; Functions for saving a message using notmuch insert.
+
+(defun notmuch-maildir-notmuch-insert-current-buffer (folder &optional create tags)
+ "Use notmuch insert to put the current buffer in the database.