<?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.phpdoctrine.org>.

 */

namespace Doctrine\ORM\Query;

/**

 * A parse tree printer for Doctrine Query Language parser.

 *

 * @author      Janne Vanhala <jpvanhal@cc.hut.fi>

 * @license     http://www.opensource.org/licenses/lgpl-license.php LGPL

 * @link        http://www.phpdoctrine.org

 * @since       2.0

 * @version     $Revision$

 */

class Printer

{

    /**

     * Current indentation level

     *

     * @var int

     */

    protected $_indent = 0;

    /**

     * Defines whether parse tree is printed (default, false) or not (true).

     *

     * @var bool

     */

    protected $_silent;

    /**

     * Constructs a new parse tree printer.

     *

     * @param bool $silent Parse tree will not be printed if true.

     */

    public function __construct($silent = false)

    {

        $this->_silent = $silent;

    }

    /**

     * Prints an opening parenthesis followed by production name and increases

     * indentation level by one.

     *

     * This method is called before executing a production.

     *

     * @param string $name production name

     */

    public function startProduction($name)

    {

        $this->println('(' . $name);

        $this->_indent++;

    }

    /**

     * Decreases indentation level by one and prints a closing parenthesis.

     *

     * This method is called after executing a production.

     */

    public function endProduction()

    {

        $this->_indent--;

        $this->println(')');

    }

    /**

     * Prints text indented with spaces depending on current indentation level.

     *

     * @param string $str text

     */

    public function println($str)

    {

        if ( ! $this->_silent) {

            echo str_repeat('    ', $this->_indent), $str, "\n";

        }

    }

}