<?php
/**
 * GroupByProcessor.php
 *
 * This file implements the processor for the GROUP-BY statements.
 *
 * Copyright (c) 2010-2012, Justin Swanhart
 * with contributions by André Rothe <arothe@phosco.info, phosco@gmx.de>
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 *   * Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright notice,
 *     this list of conditions and the following disclaimer in the documentation
 *     and/or other materials provided with the distribution.
 *
 * 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 HOLDER 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.
 */

require_once(dirname(__FILE__) . '/OrderByProcessor.php');

/**
 * 
 * This class processes the GROUP-BY statements.
 * 
 * @author arothe
 * 
 */
class GroupByProcessor extends OrderByProcessor {

    public function process($tokens, $select = array()) {
        $out = array();
        $parseInfo = $this->initParseInfo();

        if (!$tokens) {
            return false;
        }

        foreach ($tokens as $token) {
            $trim = strtoupper(trim($token));
            switch ($trim) {
            case ',':
                $parsed = $this->processOrderExpression($parseInfo, $select);
                unset($parsed['direction']);

                $out[] = $parsed;
                $parseInfo = $this->initParseInfo();
                break;
            default:
                $parseInfo['base_expr'] .= $token;
            }
        }

        $parsed = $this->processOrderExpression($parseInfo, $select);
        unset($parsed['direction']);
        $out[] = $parsed;

        return $out;
    }
}
?>