<?php
/**
 *
 * Copyright (C) Andrew Nagy 2009.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2,
 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

/**
 * Solr Utility Functions
 *
 * This class is designed to hold Solr-related support methods that may
 * be called statically.  This allows sharing of some Solr-related logic
 * between the Solr and Summon classes.
 *
 * @author      Demian Katz
 * @access      public
 */
class SolrUtils
{
    /**
     * Capitalize boolean operators in a query string to allow case-insensitivity.
     *
     * @access  public
     * @param   string  $query          The query to capitalize.
     * @return  string                  The capitalized query.
     */
    public function capitalizeBooleans($query)
    {
        // This lookahead detects whether or not we are inside quotes; it
        // is used to prevent switching case of Boolean reserved words 
        // inside quotes, since that can cause problems in case-sensitive
        // fields when the reserved words are actually used as search terms.
        $lookahead = '(?=(?:[^\"]*+\"[^\"]*+\")*+[^\"]*+$)';
        $regs = array("/\s+AND\s+{$lookahead}/i", "/\s+OR\s+{$lookahead}/i", 
                "/(\s+NOT\s+|^NOT\s+){$lookahead}/i", "/\(NOT\s+{$lookahead}/i");
        $replace = array(' AND ', ' OR ', ' NOT ', '(NOT ');
        return trim(preg_replace($regs, $replace, $query));
    }
}

?>