nextcloud/lib/geo.php

31 lines
1.1 KiB
PHP

<?php
/**
* Copyright (c) 2012 Georg Ehrke <ownclouddev at georgswebsite dot de>
* This file is licensed under the Affero General Public License version 3 or
* later.
* See the COPYING-README file.
*/
class OC_Geo{
/*
* @brief returns the closest timezone to coordinates
* @param (string) $latitude - Latitude
* @param (string) $longitude - Longitude
* @return (string) $timezone - closest timezone
*/
public static function timezone($latitude, $longitude) {
$alltimezones = DateTimeZone::listIdentifiers();
$variances = array();
//calculate for all timezones the system know
foreach($alltimezones as $timezone) {
$datetimezoneobj = new DateTimeZone($timezone);
$locationinformations = $datetimezoneobj->getLocation();
$latitudeoftimezone = $locationinformations['latitude'];
$longitudeoftimezone = $locationinformations['longitude'];
$variances[abs($latitudeoftimezone - $latitude) + abs($longitudeoftimezone - $longitude)] = $timezone;
}
//sort array and return the timezone with the smallest difference
ksort($variances);
reset($variances);
return current($variances);
}
}