discuz 함수 dgmdate

function dgmdate($timestamp, $format = 'dt', $timeoffset = '9999', $uformat = '') {
    global $_G;
    $format == 'u' && !$_G['setting']['dateconvert'] && $format = 'dt';
    static $dformat, $tformat, $dtformat, $offset, $lang;
    if($dformat === null) {
        $dformat = getglobal('setting/dateformat');
        $tformat = getglobal('setting/timeformat');
        $dtformat = $dformat.' '.$tformat;
        $offset = getglobal('member/timeoffset');
        $sysoffset = getglobal('setting/timeoffset');
        $offset = $offset == 9999 ? ($sysoffset ? $sysoffset : 0) : $offset;
        $lang = lang('core', 'date');
    }
    $timeoffset = $timeoffset == 9999 ? $offset : $timeoffset;
    $timestamp += $timeoffset * 3600;
    $format = empty($format) || $format == 'dt' ? $dtformat : ($format == 'd' ? $dformat : ($format == 't' ? $tformat : $format));
    if($format == 'u') {
        $todaytimestamp = TIMESTAMP - (TIMESTAMP + $timeoffset * 3600) % 86400 + $timeoffset * 3600;
        $s = gmdate(!$uformat ? $dtformat : $uformat, $timestamp);
        $time = TIMESTAMP + $timeoffset * 3600 - $timestamp;
        if($timestamp >= $todaytimestamp) {
            if($time > 3600) {
                $return = intval($time / 3600).' '.$lang['hour'].$lang['before'];
            } elseif($time > 1800) {
                $return = $lang['half'].$lang['hour'].$lang['before'];
            } elseif($time > 60) {
                $return = intval($time / 60).' '.$lang['min'].$lang['before'];
            } elseif($time > 0) {
                $return = $time.' '.$lang['sec'].$lang['before'];
            } elseif($time == 0) {
                $return = $lang['now'];
            } else {
                $return = $s;
            }
            if($time >=0 && !defined('IN_MOBILE')) {
                $return = '<span title="'.$s.'">'.$return.'</span>';
            }
        } elseif(($days = intval(($todaytimestamp - $timestamp) / 86400)) >= 0 && $days < 7) {
            if($days == 0) {
                $return = $lang['yday'].'&nbsp;'.gmdate($tformat, $timestamp);
            } elseif($days == 1) {
                $return = $lang['byday'].'&nbsp;'.gmdate($tformat, $timestamp);
            } else {
                $return = ($days + 1).'&nbsp;'.$lang['day'].$lang['before'];
            }
            if(!defined('IN_MOBILE')) {
                $return = '<span title="'.$s.'">'.$return.'</span>';
            }
        } else {
            $return = $s;
        }
        return $return;
    } else {
        return gmdate($format, $timestamp);
    }
}