/* Monetra CardShield Client example program in C# using XML and HttpWebRequest
 *
 * Works with .Net Compact Framework v2
 *
 * Implemented based on the Monetra CardShield Guide (Section 4, other
 * sections are not relevant to the CardShield Client implementation) in
 * conjunction with the Monetra Client Interface Protocol Specification
 *
 * Please contact support@monetra.com with any questions
 */
using System;
using System.Diagnostics;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Threading;
using System.Collections;
using System.Net;
using System.Xml;
using System.ComponentModel;
using System.Windows.Forms;
using System.Security.Cryptography.X509Certificates;

class csctestxml
{
	/* Monetra Connectivity Information
	 * NOTE: This is currently pointing to our Test Server that you may
	 *       use for initial testing if desired.  Obviously for production,
	 *       or testing with encrypted card readers, you need to point
	 *       this to your local Monetra server and the username/password
	 *       you configured there.  Please take note of the restrictions
	 *       on the username setup as listed in section 4.2 of the
	 *       CardShield Guide (the red note at the bottom of that section).
	 */
	private const string monetra_host = "testbox.monetra.com";
	private const int monetra_port = 8444;
	private const string monetra_user = "test_retail:public";
	private const string monetra_pass = "publ1ct3st";

	/* CardShield Client Connectivity Information
	* NOTE: this is the default, it is possible to change, but 99%
	*       of deployments will probably use this cardshield information
	*       as-is 
	*/
	private const string csc_host = "localhost";
	private const int csc_port = 8123;
	
	/* Windows path */
	//private const string csc_path = "C:\\Program Files\\Main Street Softworks\\Monetra CardShield Client\\monetra_cardshield_client.exe";
	/* Windows CE Path */
	private const string csc_path = "\\Program Files\\Monetra CardShield Client\\monetra_cardshield_client.exe";
	/* Unix path */
	//private const string csc_path         = "/usr/local/monetra/bin/monetra_cardshield_client";


	/*! Function to launch the cardshield client from the current process.
	 *  If we don't launch it from the current process, it won't be given
	 *  focus! (at least on Windows this is true, until the first
	 *  manual focus is performed by an end-user) */
	static void launch_csc()
	{
		Process monetra_cardshield_client = new Process();
		monetra_cardshield_client.StartInfo.FileName = csc_path;
		/* Not supported on CE
		 * monetra_cardshield_client.StartInfo.CreateNoWindow = true;
		 */

		monetra_cardshield_client.Start();

		/* Make sure the CardShield Client is ready before returning,
		* Sleep 1000ms (1s) */
		System.Threading.Thread.Sleep(1000);
	}


	/*! Trust all SSL server certificates */
	internal class AcceptAllCertificatePolicy : ICertificatePolicy
	{
		public AcceptAllCertificatePolicy()
		{
		}
		public bool CheckValidationResult(ServicePoint sPoint,
		                                  X509Certificate cert,
		                                  WebRequest wRequest, int certProb)
		{
			// *** Always accept
			return true;
		}
	}


	/*! Function to POST and XML message to a Monetra-like entity 
	*  (Monetra or the CardShield Client) via HTTPS.  It will return
	*  the key/value pairs from the XML response
	* \param[in]  host        Host to connect to
	* \param[in]  port        Port to connect to (via SSL/HTTPS)
	* \param[in]  xml         String-form XML to post
	* \return True on successful communication, False if communication failed.
	*         Note: True doesn't mean the transaction itself was successful.
	*/
	static Hashtable https_post_monetra(string host, int port, string xml)
	{
		Hashtable       response = new Hashtable();
		string          url      = "https://" + host + ":" + port.ToString();
		HttpWebRequest  req      = (HttpWebRequest)WebRequest.Create(url);
		string          xmlout;

		try {
			/* POST Request */
			
			/* Disable SSL Server Certificate Checking */
			System.Net.ServicePointManager.CertificatePolicy =
				new AcceptAllCertificatePolicy();
				
			byte[] bytes;
			bytes                  = System.Text.Encoding.ASCII.GetBytes(xml);
			req.Method             = "POST";
			req.ContentType        = "text/xml";
			req.ContentLength      = bytes.Length;
			Stream reqStream       = req.GetRequestStream();
			reqStream.Write(bytes, 0, bytes.Length);
			reqStream.Close();

			/* Read Response */
			/* Note issues with .Net CF v2 as per below:
			 *   http://blogs.msdn.com/b/andrewarnottms/archive/2007/11/19/why-net-compact-framework-fails-to-call-some-https-web-servers.aspx
			 *   http://support.microsoft.com/kb/970549
			 * If the Server is OpenSSL, this can be worked around by setting
			 * SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS
			 */
			HttpWebResponse resp   = (HttpWebResponse)req.GetResponse();
			Stream respStream      = resp.GetResponseStream();
			StreamReader rdr       = new StreamReader(respStream);
			xmlout                 = rdr.ReadToEnd();
			rdr.Close();
		} catch (System.Net.WebException e)  {
			response["code"]       = "DENY";
			response["error_code"] = "CONN_ERROR";
			response["verbiage"]   = "Connection to " + url + " failed: " +
			                         e.Message;
			return response;
		}
		XmlDocument     xmldoc     = new XmlDocument();
		xmldoc.LoadXml(xmlout);

		XmlNodeList     trans      = xmldoc.DocumentElement.
		                             SelectSingleNode("Resp").ChildNodes;
		foreach (XmlNode kv in trans) {
			response[kv.Name] = kv.InnerText;
		}
		return response;
	}


	/*! Request a ticket from the CardShield Client as documented in 
	 *  Section 4 of the Monetra CardShield Guide.
	 * \param[in] flags     Pipe (|) separated list of flags as documented in
	 *                      the Monetra CardShield Guide
	 * \param[in] trantype  Transaction Type as documented in the Monetra
	 *                      CardShield Guide (CREDIT, DEBIT, EBT, GIFT)
	 * \param[in] pindevice Applicable only to Debit and EBT, the physically
	 *                      connected PIN entry device location.  Either USB or
	 *                      the serial port address (e.g. Win: COM1, Unix:
	 *                      /dev/ttyS0).  Specify as null otherwise.
	 * \param[in] amount    Applicable only to Pin-Debit and EBT, needed to send
	 *                      the amount to the Pin-entry device.  Specify as null
	 *                      otherwise.
	 * \return Hashtable with string responses.  The keys are:
	 *        "code", "verbiage", "error_code", "ticket"
	 *        With values equivalent to the Monetra CardShield Guide 
	 *        documentation.
	 */
	static Hashtable csc_ticketrequest(string flags, string trantype,
	                                   string pindevice, string amount)
	{
		string XML;

		XML = "<MonetraTrans>" +
		        "<Trans identifier='1'>" +
		           "<username>" + monetra_user + "</username>" +
		           "<password>" + monetra_pass + "</password>" +
		           "<monetra>" + monetra_host + ":" + monetra_port.ToString() +
		             "</monetra>" +
		           "<action>ticketrequest</action>" +
		           "<flags>" + flags + "</flags>" +
		           "<trantype>" + trantype + "</trantype>";
		if (pindevice != null){
			XML = XML + "<pindevice>" + pindevice + "</pindevice>";
		}
		if (amount != null) {
			XML = XML + "<amount>" + amount + "</amount>";
		}
		XML = XML + "</Trans></MonetraTrans>";

		return https_post_monetra(csc_host, csc_port, XML);
	}


	/*! Tell the CardShield Client to shutdown.  Since we start it up,
	 *  we should make sure we turn it off prior to exiting otherwise
	 *  the user will be prompted with an error message stating the
	 *  CardShield Client is already running on the next execution
	 *  of this application!
	 */
	static void csc_shutdown()
	{
		string XML;

		XML = "<MonetraTrans>" +
		        "<Trans identifier='1'>" +
		          "<action>shutdown</action>" + 
		        "</Trans>" +
		      "</MonetraTrans>";
		https_post_monetra(csc_host, csc_port, XML);
	}
	
	
	/*! Run a transaction through Monetra using the ticket returned from the
	 *  CardShield Client.
	 *
	 *  We need to follow the Monetra Client Interface Protocol Spec here for
	 *  the most part as found on:
	 *     http://www.monetra.com/content/developers.html
	 *
	 *  The exception here is that, as per the addendum CardShield Guide,
	 *  section 4.3.1, under "Passing Ticket Data to Monetra", we replace any
	 *  sensitive information such as trackdata, account, expdate, street, zip,
	 *  cvv2 (or their e_ encrypted counterparts), with the single
	 *  "cardshieldticket" parameter filled in with the "ticket" response
	 *  parameter from the CardShield Client.  Since the CardShield Client did
	 *  the collection of this data, we wouldn't have that sensitive data
	 *  available to us anyhow, thus taking the POS out of scope for PA-DSS!
	 *
	 * NOTE: This is just an example API, you may want to add additional
	 *       optionalparameters based on your industry (such as tax,
	 *       examount[tip], and so on).
	 *
	 * \param[in] action   One of the actions available to standard users in the
	 *                     Monetra Client Interface Protocol Specification.  So
	 *                     "sale" or "preauth" might be common ones.  Though you
	 *                     can also do other requests, like store it in
	 *                     Monetra's permanent DSS token system (doc for DSS
	 *                     also available in the same place as the Monetra
	 *                     Client Interface Protocol Spec)!
	 * \param[in] amount   Dollar amount of request, in string form, with
	 *                     decimal place
	 * \param[in] ticket   Ticket returned from the Monetra CardShield Client
	 *                     (csc_ticketrequest())
	 * \param[in] ordernum Optional order number as generated by POS.  Pass null
	 *                     if not used.
	 * \return Hashtable of string key/value pairs from Monetra response.  
	 *         Please refer to the Monetra Client Interface Protocol
	 *         specification for a list of what these may be based on the action
	 *         being performed.  "code" is guaranteed to always be returned.
	 */
	static Hashtable monetra_transaction(string action, string amount,
	                                     string ticket, string ordernum)
	{
		string XML;

		/* Append the parameters for the transaction being run as per
		 * the Monetra Client Interface Protocol Specification */
		XML = "<MonetraTrans>" +
		        "<Trans identifier='1'>" +
		          "<username>" + monetra_user + "</username>" +
		          "<password>" + monetra_pass + "</password>" +
		          "<action>" + action + "</action>" +
		          "<cardshieldticket>" + ticket + "</cardshieldticket>" +
		          "<amount>" + amount + "</amount>";

		if (ordernum != null) {
			XML = XML + "<ordernum>" + ordernum + "</ordernum>";
		}

		XML = XML + "</Trans></MonetraTrans>";

		return https_post_monetra(monetra_host, monetra_port, XML);
	}


	/*! Main entry point to this application to be executed */
	static void Main()
	{
		Hashtable response;
		string ticket;

		/* Step1: Launch the CardShield Client */
		launch_csc();
		MessageBox.Show("CardShield Client Launched");

		/* Step2: Request Ticket from the CardShield Client using Keyed Entry
		 * Credit Card */
		response = csc_ticketrequest("KEY|AVS|CVV", "CREDIT", null, null);
		if (String.Compare((string)response["code"], "AUTH", true) != 0) {
			csc_shutdown();
			string msg = "TicketRequest failure.\r\n" +
			             "code = " + (string)response["code"] + "\r\n" +
			             "error_code = " + (string)response["error_code"] +
			               "\r\n" +
			             "verbiage = " + (string)response["verbiage"] + "\r\n";
			MessageBox.Show(msg);
			return;
		}

		ticket = (string)response["ticket"];
		MessageBox.Show("Received ticket: " + ticket);

		/* Step3: Send Transaction to Monetra with Ticket */
		response = monetra_transaction("sale", "12.00", ticket, "1234567890");
		string resultMsg = "";
		if (String.Compare((string)response["code"], "AUTH", true) != 0) {
			resultMsg = "Transaction Failed.\r\n";
		} else {
			resultMsg = "Transaction SUCCESSFUL!\r\n";
		}
        
		/* Print out all the response key/value pairs ... */
		foreach (DictionaryEntry kv in response) {
			resultMsg = resultMsg + (string)kv.Key + " = " + (string)kv.Value +
			            "\r\n";
		}

		MessageBox.Show(resultMsg);
		/* NOTE: No real reason to exit here ... we could just keep running
		 *       Steps 2 and 3 all day long.  No reason to keep disconnecting and
		 *       reconnecting, or starting/stopping the CardShield Client.
		 */

		/* Step4: Cleanup */
		csc_shutdown();
	}
}