/**
  * destroyVoucher function.
  *
  * @access public
  *
  * @param string $hash
  *
  * @return Voucher
  */
 public function destroyVoucher($hash)
 {
     if ($voucher = $this->model->where('hash', '=', $hash)->first()) {
         if ($voucher->delete()) {
             return $voucher;
         }
     }
     return false;
 }
 /**
  * expireVoucher function.
  *
  * @access public
  *
  * @param string $hash
  *
  * @return Voucher
  */
 public function expireVoucher($hash)
 {
     if ($voucher = $this->model->where('hash', '=', $hash)->first()) {
         $voucher->is_expired = 1;
         $voucher->expired_at = date('Y-m-d H:i:s');
         if ($voucher->save()) {
             return $voucher;
         }
     }
     return false;
 }