ouch

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Threading;

namespace ZarinPal_Pay_Lib
{
    public class ZarinPay
    {
        private string _MerchantID, _Description, _CallbackURL, _Email, _Mobile;
        private int _Amount;
        public delegate void PArgs(object sender, PayArgs e);
        public event PArgs OnPaymentAction;
        /// <summary>
        /// Initilize a payment
        /// </summary>
        /// <param name="MerchantID">Reciever Unique ID</param>
        /// <param name="Amount">Amount to send</param>
        /// <param name="Description"></param>
        /// <param name="CallbackURL">Where to redirect after finish</param>
        /// <param name="Email">Sender mail address ( optionl )</param>
        /// <param name="Mobile">Sender mobile number ( optional )</param>
        /// <returns>Returns authority id</returns>
        public ZarinPay(string MerchantID, int Amount, string Description, string CallbackURL, string Email = "", string Mobile = "")
        {
            _MerchantID = MerchantID;
            _Amount = Amount;
            _Description = Description;
            _CallbackURL = CallbackURL;
            _Email = Email;
            _Mobile = Mobile;
        }
        /// <summary>
        /// Starts payment
        /// </summary>
        /// <returns>Returns payment autohority id</returns>
        public string StartPay()
        {
            ZarinPal.PaymentGatewayImplementationServicePortTypeClient request = new ZarinPal.PaymentGatewayImplementationServicePortTypeClient();
            string autohority = string.Empty;
            int value = request.PaymentRequest(_MerchantID, _Amount, _Description, _Email, _Mobile, _CallbackURL, out autohority);
            if (value > 0)
            {
                new Thread(() =>
                {
                    CheckPaymentStatus(autohority);
                }).Start();
                return autohority;
            }
            else
            {
                return null;
            }
        }
        private void CheckPaymentStatus(string autohority)
        {
            ZarinPal.PaymentGatewayImplementationServicePortTypeClient request = new ZarinPal.PaymentGatewayImplementationServicePortTypeClient();
            long refID = -1;
            while (true)
            {
                int verf = request.PaymentVerification(_MerchantID, autohority, _Amount, out refID);
                if (verf > 0)
                {
                    if(OnPaymentAction != null)
                    {
                        OnPaymentAction(this, new PayArgs(verf, autohority, refID));
                    }
                    break;
                }
                else
                {
                    if (verf != -21)
                    {
                        if (OnPaymentAction != null)
                        {
                            OnPaymentAction(this, new PayArgs(verf, autohority, refID));
                        }
                        break;
                    }
                }
            }
        }
        public string MerchantID
        {
            get { return _MerchantID; }
        }
        public string Description
        {
            get { return _Description; }
        }
        public string CallbackURL
        {
            get { return _CallbackURL; }
        }
        public string Email
        {
            get { return _Email; }
        }
        public string Mobile
        {
            get { return _Mobile; }
        }
        public int Amount
        {
            get { return _Amount; }
        }
        public class PayArgs
        {
            private int _Status;
            private string _Autohority;
            private long _RefID;
            public PayArgs(int Status, string Autohority, long RefID)
            {
                _Status = Status;
                _Autohority = Autohority;
                _RefID = RefID;
            }
            public int Status
            {
                get { return _Status; }
            }
            public string Autohority
            {
                get { return _Autohority; }
            }
            public long RefID
            {
                get { return _RefID; }
            }
        }
    }
}