특정시간으로부터 얼마나 지났는지 채택완료

function get_time($datetime){
    $past_timestamp = strtotime($datetime);
    $curr_timestamp = strtotime(G5_TIME_YMDHIS);

    $total_time = $curr_timestamp - $past_timestamp;

    $days = floor($total_time/86400);
    $time = $total_time - ($days*86400);
    $hours = floor($time/3600);
    $time = $time - ($hours*3600);
    $min = floor($time/60);
    $sec = $time - ($min*60);

    $return = '';
    if($days>0){
        $return = "{$days}일 전";
    }elseif($hours>0){
        $return = "{$hours}시간 전";
    }else{
        $return = "{$min}분 전";
    }

    return $return;
}

echo get_time('2020-01-30');