Math.php

<?php
/*
 *  $Id$
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the LGPL. For more information, see
 * <http://www.doctrine-project.org>.
 */

namespace Doctrine\ORM\Query\Expr;

/**
 * Expression class for DQL math statements
 *
 * @license http://www.opensource.org/licenses/lgpl-license.php LGPL
 * @link    www.doctrine-project.org
 * @since   2.0
 * @version $Revision$
 * @author  Guilherme Blanco <guilhermeblanco@hotmail.com>
 * @author  Jonathan Wage <jonwage@gmail.com>
 * @author  Roman Borschel <roman@code-factory.org>
 */
class Math
{
    private $_leftExpr;
    private $_operator;
    private $_rightExpr;

    public function __construct($leftExpr, $operator, $rightExpr)
    {
        $this->_leftExpr  = $leftExpr;
        $this->_operator  = $operator;
        $this->_rightExpr = $rightExpr;
    }

    public function __toString()
    {
        // Adjusting Left Expression
        $leftExpr = (string) $this->_leftExpr;
        
        if ($this->_leftExpr instanceof Math) {
            $leftExpr = '(' . $leftExpr . ')';
        }
        
        // Adjusting Right Expression
        $rightExpr = (string) $this->_rightExpr;
        
        if ($this->_rightExpr instanceof Math) {
            $rightExpr = '(' . $rightExpr . ')';
        }
    
        return $leftExpr . ' ' . $this->_operator . ' ' . $rightExpr;
    }
}