<?php
/**
 * $Id: AdvancedQuery.php 1631 2007-05-12 22:40:28Z matthieu $
 */
if (!class_exists('Google_AdvancedQuery')) {
    if (!defined('__CLASS_PATH__')) {
        define('__CLASS_PATH__', realpath(dirname(__FILE__) . '/../'));
    }
    require_once __CLASS_PATH__ . '/Autoload.php';
    /**
     * tools for making easy query on google search browser
     * @author Matthieu MARY <hide@address.com>
     * @license http://opensource.org/licenses/gpl-license.php GNU Public License
     * @package google
     */
    class Google_AdvancedQuery extends Google_Query {

        const __PATTERN_REMOTE_URL__ = "http://www.phplibrairies.com/display_pattern_google_query.txt";

        const __PATTERN_LOCAL_FILE__ = "google.pattern";
        /**
         * builder
         * @param bool bCache : does you wants to enable cache?
         * @param int $update_pattern_frequency : number of seconds when pattern
         * must be updated
         * @return void
         * @access public
         * @throws Exception
         */
        public function __construct($update_pattern_frequency = 604800, $cache = null) {
            parent :: __construct($cache);
            $destinationFile = dirname(__FILE__) . "/" . self :: __PATTERN_LOCAL_FILE__;
            $new_pattern = '';
            // if we are over the duration validity, we delete the file to retrieve the new pattern
            if (file_exists($destinationFile) && ((time() - $update_pattern_frequency) > filemtime($destinationFile))) {
                unlink($destinationFile);
            }
            // if not file exists, we update the pattern from remote adress
            if (!file_exists($destinationFile)) {
                $new_pattern = $this->_retrievePattern();
                if (empty ($new_pattern)) {
                    throw new Exception("Cannot retrieve the new detection pattern. send email to hide@address.com to ensure that remote url work properly");
                }
                else {
                    if (!file_put_contents($destinationFile, $new_pattern)) {
                        throw new Exception("Cannot write $destinationFile to put the new detection pattern. check your write permissions on this folder");
                    }
                }
            }
            // update parent from the new detection pattern
            if (file_exists($destinationFile)) {
                $this->_updatePattern((empty ($new_pattern) ? trim(file_get_contents($destinationFile)) : $new_pattern));
            }
        }
        /**
         * return the file which contains the pattern
         * @access public
         * @return string
         * @static
         */
        public static function getFilePattern() {
            return dirname(__FILE__).'/'.self :: __PATTERN_LOCAL_FILE__;
        }
        /**
         * retrieve the latest pattern from remote url
         * @access private
         * @return string
         */
        private function _retrievePattern() {
            return trim(file_get_contents(self :: __PATTERN_REMOTE_URL__));
        }
    }
}