org-mode/org-mhe.el

;;; org-mhe.el - Support for links to MHE messages in Org-mode

;; Copyright (C) 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.

;; Author: Carsten Dominik <carsten at orgmode dot org>
;; Keywords: outlines, hypermedia, calendar, wp
;; Homepage: http://orgmode.org
;; Version: 1.0
;;
;; This file is part of GNU Emacs.
;;
;; GNU Emacs 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, or (at your option)
;; any later version.

;; GNU Emacs 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 GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;;; Commentary:

;; This file implements links to MHE messages for Org-mode.
;; Org-mode loads this module by default - if this is not what you want,
;; configure the variable `org-modules'.

(require 'org)

;; Customization variables
(defcustom org-mhe-search-all-folders nil
  "Non-nil means, that the search for the mh-message will be extended to
all folders if the message cannot be found in the folder given in the link.
Searching all folders is very efficient with one of the search engines
supported by MH-E, but will be slow with pick."
  :group 'org-link-follow
  :type 'boolean)

;; Declare external functions and variables
(declare-function mh-display-msg "mh-show" (msg-num folder-name))
(declare-function mh-find-path "mh-utils" ())
(declare-function mh-get-header-field "mh-utils" (field))
(declare-function mh-get-msg-num "mh-utils" (error-if-no-message))
(declare-function mh-header-display "mh-show" ())
(declare-function mh-index-previous-folder "mh-search" ())
(declare-function mh-normalize-folder-name "mh-utils"
		  (folder &optional empty-string-okay dont-remove-trailing-slash
			  return-nil-if-folder-empty))
(declare-function mh-search "mh-search"
		  (folder search-regexp &optional redo-search-flag
			  window-config))
(declare-function mh-search-choose "mh-search" (&optional searcher))
(declare-function mh-show "mh-show" (&optional message redisplay-flag))
(declare-function mh-show-buffer-message-number "mh-comp" (&optional buffer))
(declare-function mh-show-header-display "mh-show" t t)
(declare-function mh-show-msg "mh-show" (msg))
(declare-function mh-show-show "mh-show" t t)
(declare-function mh-visit-folder "mh-folder" (folder &optional
						      range index-data))
(defvar mh-progs)
(defvar mh-current-folder)
(defvar mh-show-folder-buffer)
(defvar mh-index-folder)
(defvar mh-searcher)

;; Install the link type
(org-add-link-type "mhe" 'org-mhe-open)
(add-hook 'org-store-link-functions 'org-mhe-store-link)

;; Implementation
(defun org-mhe-store-link ()
  "Store a link to an MHE folder or message."
  (when (or (equal major-mode 'mh-folder-mode)
	    (equal major-mode 'mh-show-mode))
    (let ((from (org-mhe-get-header "From:"))
	  (to (org-mhe-get-header "To:"))
	  (message-id (org-mhe-get-header "Message-Id:"))
	  (subject (org-mhe-get-header "Subject:"))
	  link desc)
      (org-store-link-props :type "mh" :from from :to to
			    :subject subject :message-id message-id)
      (setq desc (org-email-link-description))
      (setq link (org-make-link "mhe:" (org-mhe-get-message-real-folder) "#"
				(org-remove-angle-brackets message-id)))
      (org-add-link-props :link link :description desc))))

(defun org-mhe-open (path)
  "Follow an MHE message link."
  (let (folder article)
    (if (not (string-match "\\`\\([^#]+\\)\\(#\\(.*\\)\\)?" path))
	(error "Error in MHE link"))
    (setq folder (match-string 1 path)
	  article (match-string 3 path))
    (org-mhe-follow-link folder article)))

;;; mh-e integration based on planner-mode
(defun org-mhe-get-message-real-folder ()
  "Return the name of the current message real folder, so if you use
sequences, it will now work."
  (save-excursion
    (let* ((folder
            (if (equal major-mode 'mh-folder-mode)
                mh-current-folder
              ;; Refer to the show buffer
              mh-show-folder-buffer))
           (end-index
            (if (boundp 'mh-index-folder)
                (min (length mh-index-folder) (length folder))))
           )
      ;; a simple test on mh-index-data does not work, because
      ;; mh-index-data is always nil in a show buffer.
      (if (and (boundp 'mh-index-folder)
               (string= mh-index-folder (substring folder 0 end-index)))
          (if (equal major-mode 'mh-show-mode)
              (save-window-excursion
		(let (pop-up-frames)
		  (when (buffer-live-p (get-buffer folder))
		    (progn
		      (pop-to-buffer folder)
		      (org-mhe-get-message-folder-from-index)
		      )
		    )))
            (org-mhe-get-message-folder-from-index)
            )
        folder
        )
      )))

(defun org-mhe-get-message-folder-from-index ()
  "Returns the name of the message folder in a index folder buffer."
  (save-excursion
    (mh-index-previous-folder)
    (re-search-forward "^\\(+.*\\)$" nil t)
    (message "%s" (match-string 1))))

(defun org-mhe-get-message-folder ()
  "Return the name of the current message folder.  Be careful if you
use sequences."
  (save-excursion
    (if (equal major-mode 'mh-folder-mode)
        mh-current-folder
      ;; Refer to the show buffer
      mh-show-folder-buffer)))

(defun org-mhe-get-message-num ()
  "Return the number of the current message.  Be careful if you
use sequences."
  (save-excursion
    (if (equal major-mode 'mh-folder-mode)
        (mh-get-msg-num nil)
      ;; Refer to the show buffer
      (mh-show-buffer-message-number))))

(defun org-mhe-get-header (header)
  "Return a header of the message in folder mode.  This will create a
show buffer for the corresponding message.  If you have a more clever
idea..."
  (let* ((folder (org-mhe-get-message-folder))
         (num (org-mhe-get-message-num))
         (buffer (get-buffer-create (concat "show-" folder)))
         (header-field))
  (with-current-buffer buffer
    (mh-display-msg num folder)
    (if (equal major-mode 'mh-folder-mode)
        (mh-header-display)
      (mh-show-header-display))
    (set-buffer buffer)
    (setq header-field (mh-get-header-field header))
    (if (equal major-mode 'mh-folder-mode)
        (mh-show)
      (mh-show-show))
    header-field)))

(defun org-mhe-follow-link (folder article)
  "Follow an MHE link to FOLDER and ARTICLE.
If ARTICLE is nil FOLDER is shown.  If the configuration variable
`org-mhe-search-all-folders' is t and `mh-searcher' is pick,
ARTICLE is searched in all folders.  Indexed searches (swish++,
namazu, and others supported by MH-E) will always search in all
folders."
  (require 'mh-e)
  (require 'mh-search)
  (require 'mh-utils)
  (mh-find-path)
  (if (not article)
      (mh-visit-folder (mh-normalize-folder-name folder))
    (setq article (org-add-angle-brackets article))
    (mh-search-choose)
    (if (equal mh-searcher 'pick)
        (progn
          (mh-search folder (list "--message-id" article))
          (when (and org-mhe-search-all-folders
                     (not (org-mhe-get-message-real-folder)))
            (kill-this-buffer)
            (mh-search "+" (list "--message-id" article))))
      (mh-search "+" article))
    (if (org-mhe-get-message-real-folder)
        (mh-show-msg 1)
      (kill-this-buffer)
      (error "Message not found"))))

(provide 'org-mhe)

;;; org-mhe.el ends here