nextcloud/lib/private/datetimezone.php

120 lines
3.3 KiB
PHP

<?php
/**
* @author Joas Schilling <nickvergessen@owncloud.com>
* @author Morris Jobke <hey@morrisjobke.de>
*
* @copyright Copyright (c) 2015, ownCloud, Inc.
* @license AGPL-3.0
*
* This code is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License, version 3,
* along with this program. If not, see <http://www.gnu.org/licenses/>
*
*/
namespace OC;
use OCP\IConfig;
use OCP\IDateTimeZone;
use OCP\ISession;
class DateTimeZone implements IDateTimeZone {
/** @var IConfig */
protected $config;
/** @var ISession */
protected $session;
/**
* Constructor
*
* @param IConfig $config
* @param ISession $session
*/
public function __construct(IConfig $config, ISession $session) {
$this->config = $config;
$this->session = $session;
}
/**
* Get the timezone of the current user, based on his session information and config data
*
* @return \DateTimeZone
*/
public function getTimeZone() {
$timeZone = $this->config->getUserValue($this->session->get('user_id'), 'core', 'timezone', null);
if ($timeZone === null) {
if ($this->session->exists('timezone')) {
return $this->guessTimeZoneFromOffset($this->session->get('timezone'));
}
$timeZone = $this->getDefaultTimeZone();
}
try {
return new \DateTimeZone($timeZone);
} catch (\Exception $e) {
\OCP\Util::writeLog('datetimezone', 'Failed to created DateTimeZone "' . $timeZone . "'", \OCP\Util::DEBUG);
return new \DateTimeZone($this->getDefaultTimeZone());
}
}
/**
* Guess the DateTimeZone for a given offset
*
* We first try to find a Etc/GMT* timezone, if that does not exist,
* we try to find it manually, before falling back to UTC.
*
* @param mixed $offset
* @return \DateTimeZone
*/
protected function guessTimeZoneFromOffset($offset) {
try {
// Note: the timeZone name is the inverse to the offset,
// so a positive offset means negative timeZone
// and the other way around.
if ($offset > 0) {
$timeZone = 'Etc/GMT-' . $offset;
} else {
$timeZone = 'Etc/GMT+' . abs($offset);
}
return new \DateTimeZone($timeZone);
} catch (\Exception $e) {
// If the offset has no Etc/GMT* timezone,
// we try to guess one timezone that has the same offset
foreach (\DateTimeZone::listIdentifiers() as $timeZone) {
$dtz = new \DateTimeZone($timeZone);
$dtOffset = $dtz->getOffset(new \DateTime());
if ($dtOffset == 3600 * $offset) {
return $dtz;
}
}
// No timezone found, fallback to UTC
\OCP\Util::writeLog('datetimezone', 'Failed to find DateTimeZone for offset "' . $offset . "'", \OCP\Util::DEBUG);
return new \DateTimeZone($this->getDefaultTimeZone());
}
}
/**
* Get the default timezone of the server
*
* Falls back to UTC if it is not yet set.
*
* @return string
*/
protected function getDefaultTimeZone() {
$serverTimeZone = date_default_timezone_get();
return $serverTimeZone ?: 'UTC';
}
}