;;; rails-project.el ---

;; Copyright (C) 2006 Dmitry Galinsky <dima dot exe at gmail dot com>

;; Authors: Dmitry Galinsky <dima dot exe at gmail dot com>,

;; Keywords: ruby rails languages oop

;; $URL: svn+ssh://rubyforge/var/svn/emacs-rails/trunk/rails.el $

;; $Id: rails.el 149 2007-03-29 15:07:49Z dimaexe $

;;; License

;; 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 2

;; 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, write to the Free Software

;; Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

;;; Code:

(defun rails-project:root ()

  "Return RAILS_ROOT if this file is a part of a Rails application,

else return nil"

  (let ((curdir default-directory)

        (max 10)

        (found nil))

    (while (and (not found) (> max 0))

      (progn

        (if (file-exists-p (concat curdir "config/environment.rb"))

            (progn

              (setq found t))

          (progn

            (setq curdir (concat curdir "../"))

            (setq max (- max 1))))))

    (if found (expand-file-name curdir))))

(defmacro* rails-project:with-root ((root) &body body)

  "If you use `rails-project:root' or functions related on it

several times in a block of code, you can optimize your code by

using this macro. Also, blocks of code will be executed only if

rails-root exist.

 (rails-project:with-root (root)

    (foo root)

    (bar (rails-core:file \"some/path\")))

 "

 `(let ((,root (rails-project:root)))

    (when ,root

      (flet ((rails-project:root () ,root))

        ,@body))))

(defmacro rails-project:in-root (&rest body)

  "Set the default directory to the Rails root directory while

BODY is executed."

  (let ((root (gensym)))

    `(rails-project:with-root

      (,root)

      (let ((default-dir ,root))

        ,@body))))

(defmacro* rails-project:in-root-with-cd (&rest body)

  (let ((root (gensym)))

  `(rails-project:with-root (,root)

    (in-directory (,root) ,@body))))

(defun rails-project:compile-in-root (command)

  (rails-project:in-root-with-cd

   (compile command)))

(defun rails-project:name ()

  "Return the name of current Rails project."

  (replace-regexp-in-string "^.*/\\(.*\\)/$" "\\1"

          (directory-name (rails-project:root))))

(provide 'rails-project)