using System;

using System.Security.Cryptography;

using System.Text;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        var initialPayment = false;

        var freeStartPeriod = 0; // free start period in days

        var staging = false;

        const string PublicKey = "0oa70WuefiddqLjqlTlp"; // Enter your service public key

        const string PrivateKey = "m2vQxqNixqrEDcQ2heVr"; // Enter your service private key

        var customerAccountNumber = "Customer-1";

        var msisdn = "201286438693"; // Mobile number

        var operatorCode = "60201"; // operator code

        var subscriptionPlanId = 3; 

        var initialPaymentproductId = "100Points";

        var initialPaymentDate = DateTime.Now.AddDays(freeStartPeriod).ToString("yyyy-MM-dd HH:mm:ssZ");

        var executeInitialPaymentNow = initialPayment;

        var recurringPaymentproductId = "100Points";

        var productCatalogName = "HETest";

        var executeRecurringPaymentNow = false;

        var contractStartDate = DateTime.UtcNow.ToString("yyyy-MM-dd HH:mm:ssZ");

        var contractEndDate = DateTime.Now.AddYears(10).ToString("yyyy-MM-dd HH:mm:ssZ");

        var autoRenewContract = true;

        var language = 1;

        var sendVerificationSMS = true;

        var allowMultipleFreeStartPeriods = false;

        var headerEnrichmentReferenceCode = "";

        var smsId = "";

        var message = customerAccountNumber + msisdn + operatorCode + subscriptionPlanId.ToString() + initialPaymentproductId + initialPaymentDate + executeInitialPaymentNow.ToString().ToLower() + recurringPaymentproductId + productCatalogName + executeRecurringPaymentNow.ToString().ToLower() + contractStartDate + contractEndDate + autoRenewContract.ToString().ToLower() + language.ToString() + sendVerificationSMS.ToString().ToLower() + allowMultipleFreeStartPeriods.ToString().ToLower() + headerEnrichmentReferenceCode + smsId;

        var digest = CalculateDigest(PublicKey, PrivateKey, message);

        //Console.WriteLine(digest);

        var theDigest = CalculateDigest(PublicKey, PrivateKey, message);

        Console.WriteLine("{\n\"signature\": \"" +theDigest+"\",\n"+

                          "\"customerAccountNumber\": \"" +customerAccountNumber+"\",\n"+

                          "\"msisdn\": \"" +msisdn+"\",\n"+

                          "\"operatorCode\": \"" +operatorCode+"\",\n"+

                          "\"subscriptionPlanId\": \"" +subscriptionPlanId+"\",\n"+

                          "\"initialPaymentproductId\": \"" +initialPaymentproductId+"\",\n"+

                          "\"initialPaymentDate\": \"" +initialPaymentDate+"\",\n"+

                          "\"executeInitialPaymentNow\": \"" +executeInitialPaymentNow.ToString().ToLower()+"\",\n"+

                          "\"executeRecurringPaymentNow\": \"" +executeRecurringPaymentNow.ToString().ToLower()+"\",\n"+

                          "\"recurringPaymentproductId\": \"" +recurringPaymentproductId+"\",\n"+

                          "\"productCatalogName\": \"" +productCatalogName+"\",\n"+

                          "\"autoRenewContract\": \"" +autoRenewContract.ToString().ToLower()+"\",\n"+

                          "\"sendVerificationSMS\": \"" +sendVerificationSMS.ToString().ToLower()+"\",\n"+

                          "\"allowMultipleFreeStartPeriods\": \"" +allowMultipleFreeStartPeriods.ToString().ToLower()+"\",\n"+

                          "\"contractStartDate\": \"" +contractStartDate+"\",\n"+

                          "\"contractEndDate\": \"" +contractEndDate+"\",\n"+

                          "\"language\": \"" +language+"\",\n"+

                          "\"headerEnrichmentReferenceCode\": \"" +headerEnrichmentReferenceCode+"\",\n"+

                          "\"smsId\": \"" +smsId+"\"\n}");

    }

​

    public static string CalculateDigest(string publicKey, string privateKey, string message)

    {

        var digest = "";

        var hash = new System.Security.Cryptography.HMACSHA256(System.Text.Encoding.UTF8.GetBytes(privateKey));

        var correctHash = string.Join(string.Empty, hash.ComputeHash(System.Text.Encoding.UTF8.GetBytes(message)).Select(b => b.ToString("x2")));

        digest = publicKey + ":" + correctHash;

​

        return digest;

    }

}