Timestamp PHP SOURCE

<?
class DateHelper{
 public static function get_time_ago($time_stamp)
 {
  $time_difference = strtotime('now') - $time_stamp;

  if ($time_difference >= 60 * 60 * 24 * 365.242199)
  {
return DateHelper::get_time_ago_string($time_stamp, 60 * 60 * 24 * 365.242199, 'tahun');
  }
  elseif ($time_difference >= 60 * 60 * 24 * 30.4368499)
  {
return DateHelper::get_time_ago_string($time_stamp, 60 * 60 * 24 * 30.4368499, 'bulan');
  }
  elseif ($time_difference >= 60 * 60 * 24 * 7)
  {
return DateHelper::get_time_ago_string($time_stamp, 60 * 60 * 24 * 7, 'minggu');
  }
  elseif ($time_difference >= 60 * 60 * 24)
  {
return DateHelper::get_time_ago_string($time_stamp, 60 * 60 * 24, 'hari');
  }
  elseif ($time_difference >= 60 * 60)
  {
return DateHelper::get_time_ago_string($time_stamp, 60 * 60, 'jam');
  }
  else
  {
return DateHelper::get_time_ago_string($time_stamp, 60, 'menit');
  }
 }

 public static function get_time_ago_string($time_stamp, $divisor, $time_unit)
 {
  $time_difference = strtotime("now") - $time_stamp;
  $time_units      = floor($time_difference / $divisor);

  settype($time_units, 'string');

  if ($time_units === '0')
  {
   return 'less than 1 ' . $time_unit . ' lalu';
  }
  elseif ($time_units === '1')
  {
   return '1 ' . $time_unit . ' lalu';
  }
  else
  {
return $time_units . ' ' . $time_unit . ' yang lalu';
  }
 }
}

  error_reporting(0);
  session_start();   
 echo "".DateHelper::get_time_ago('1142006887')."";

// echo strtotime("now");
?>