<?php

/**
 * $Id:$
 *
 * KnowledgeTree Open Source Edition
 * Document Management Made Simple
 * Copyright (C) 2004 - 2007 The Jam Warehouse Software (Pty) Limited
 *
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License version 3 as published by the
 * Free Software Foundation.
 *
 * 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 <http://www.gnu.org/licenses/>.
 *
 * You can contact The Jam Warehouse Software (Pty) Limited, Unit 1, Tramber Place,
 * Blake Street, Observatory, 7925 South Africa. or email info@knowledgetree.com.
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU General Public License version 3.
 *
 * In accordance with Section 7(b) of the GNU General Public License version 3,
 * these Appropriate Legal Notices must retain the display of the "Powered by
 * KnowledgeTree" logo and retain the original copyright notice. If the display of the
 * logo is not reasonably feasible for technical reasons, the Appropriate Legal Notices
 * must display the words "Powered by KnowledgeTree" and retain the original
 * copyright notice.
 * Contributor( s): ______________________________________
 *
 */

class ModifiedDeltaField extends DBFieldExpr
{
	private $modifiedName;

    public function __construct()
    {
        parent::__construct('modified', 'documents', _kt('Modified Delta'));
        $this->setAlias('ModifiedDelta');
        $this->isValueQuoted(false);
    }

    public function modifyName($sql)
    {
    	$this->modifiedName = $sql;
    	$now = date('Y-m-d');


    	return "cast('$now' as date)";
    }

    public function modifyValue($value)
    {
		return "cast(cast($this->modifiedName as date) + $value as date)";
    }

    public function getInputRequirements()
    {
        return array('value'=>array('type'=>FieldInputType::DATEDIFF));
    }

    public function is_valid()
    {
        return DefaultOpCollection::validateParent($this, DefaultOpCollection::$between);
    }
}

?>