<?php
/** @package    verysimple::Payment */

/** import supporting libraries */
require_once("PaymentProcessor.php");

/**
 * PayPal extends the generic PaymentProcessor object to process
 * a PaymentRequest through the PayPal direct payment API.
 *
 * @package    verysimple::Payment
 * @author     VerySimple Inc.
 * @copyright  1997-2012 VerySimple, Inc.
 * @license    http://www.gnu.org/licenses/lgpl.html  LGPL
 * @version    2.1
 */
class PayPal extends PaymentProcessor
{
	// used by paypal - 'sandbox' or 'beta-sandbox' or 'live'
	private $environment = 'sandbox';


	/**
	* Called on contruction
	* @param bool $test  set to true to enable test mode.  default = false
	*/
	function Init($testmode)
	{
		// set the post url depending on whether we're in test mode or not
		$this->environment = $testmode ? 'sandbox' : 'live';
	}

	/**
	 * @see PaymentProcessor::Refund()
	 */
	function Refund(RefundRequest $req)
	{

		$resp = new PaymentResponse();
		$resp->OrderNumber = $req->InvoiceId;

		$nvpStr = "&TRANSACTIONID=" . urlencode($req->TransactionId);

		$nvpStr .= "&CURRENCYCODE=" . urlencode($req->TransactionCurrency);

		if($req->RefundType == RefundRequest::$REFUND_TYPE_PARTIAL)
		{
			if (!$req->RefundAmount)
			{
				$resp->IsSuccess = false;
				$resp->ResponseMessage = "RefundAmount is required for partial refund";
				return $resp;
			}
			$nvpStr .= "&REFUNDTYPE=Partial&AMT=" . urldecode($req->RefundAmount);
		}
		else
		{
			$nvpStr .= "&REFUNDTYPE=Full";
		}

		if ($req->Memo) $nvpStr .= "&NOTE=" . urlencode($req->Memo);

		if ($req->InvoiceId) $nvpStr .= "&INVOICEID=" . urlencode($req->InvoiceId);

		// Execute the API operation
		$resp->RawResponse = $this->PPHttpPost('RefundTransaction', $nvpStr);

		if("SUCCESS" == strtoupper($resp->RawResponse["ACK"]) || "SUCCESSWITHWARNING" == strtoupper($resp->RawResponse["ACK"]))
		{

			/* SAMPLE SUCCESS RESPONSE
			Array (
				[REFUNDTRANSACTIONID] => 5L51568382268602F
				[FEEREFUNDAMT] => 0%2e18
				[GROSSREFUNDAMT] => 5%2e15
				[NETREFUNDAMT] => 4%2e97
				[CURRENCYCODE] => USD
				[TIMESTAMP] => 2012%2d03%2d22T23%3a25%3a25Z
				[CORRELATIONID] => 2a2cc13c7c64a
				[ACK] => Success
				[VERSION] => 62%2e0
				[BUILD] => 2649250
			)
			*/

			$resp->IsSuccess = true;
			$resp->TransactionId = $resp->RawResponse['REFUNDTRANSACTIONID'];
			$resp->OrderNumber = $req->InvoiceId;
			$resp->ResponseMessage = urldecode($resp->RawResponse['GROSSREFUNDAMT'] . ' ' . $resp->RawResponse['CURRENCYCODE']) . " was sucessfully refunded.";
		}
		else
		{
			/* SAMPLE ERROR RESPONSE:
			Array (
				[TIMESTAMP] => 2012%2d03%2d22T23%3a15%3a22Z
				[CORRELATIONID] => ae19bab2b4b1
				[ACK] => Failure [VERSION] => 62%2e0
				[BUILD] => 2649250
				[L_ERRORCODE0] => 10004
				[L_SHORTMESSAGE0] => Transaction%20refused%20because%20of%20an%20invalid%20argument%2e%20See%20additional%20error%20messages%20for%20details%2e
				[L_LONGMESSAGE0] => The%20transaction%20id%20is%20not%20valid
				[L_SEVERITYCODE0] => Error
			)
			*/

			$resp->IsSuccess = false;
			$resp->ResponseCode = urldecode( $this->GetArrayVal($resp->RawResponse,"L_ERRORCODE0") );
			$resp->ResponseMessage = $this->GetErrorMessage($resp->RawResponse);
		}

		$resp->ParsedResponse = "";
		$delim = "";
		foreach (array_keys($resp->RawResponse) as $key)
		{
			$resp->ParsedResponse .= $delim . $key . "='" . urldecode( $resp->RawResponse[$key]) . "'";
			$delim = ", ";
		}

		return $resp;
	}

	/**
	* Process a PaymentRequest
	* @param PaymentRequest $req Request object to be processed
	* @return PaymentResponse
	*/
	function Process(PaymentRequest $req)
	{
		$resp = new PaymentResponse();
		$resp->OrderNumber = $req->OrderNumber;

		// before bothering with contacting the processor, check for some basic fields
		if ($req->CCNumber == '')
		{
			$resp->IsSuccess = false;
			$resp->ResponseCode = "0";
			$resp->ResponseMessage = "No Credit Card Number Provided";
			return $resp;
		}

		if ($req->CustomerFirstName == '')
		{
			$resp->IsSuccess = false;
			$resp->ResponseCode = "0";
			$resp->ResponseMessage = "No Cardholder Name Provided";
			return $resp;
		}

		// post to paypal service
		// Set request-specific fields.
		$paymentType = $req->TransactionType == PaymentRequest::$TRANSACTION_TYPE_AUTH_CAPTURE
			? urlencode('Sale')
			: urlencode('Authorization') ;
		$firstName = urlencode($req->CustomerFirstName);
		$lastName = urlencode($req->CustomerLastName);
		$creditCardType = urlencode( trim($req->CCType) );
		$creditCardNumber = urlencode( trim($req->CCNumber) );

		// month needs to be two digits - padded with leading zero if necessary
		$padDateMonth = urlencode( trim(str_pad($req->CCExpMonth, 2, '0', STR_PAD_LEFT)) );

		// year needs to be full 4-digit
		$expDateYear = urlencode( $this->GetFullYear( trim($req->CCExpYear) ) );

		$email = (urlencode($req->CustomerEmail));
		$invoiceNum = (urlencode($req->InvoiceNumber));
		$orderDesc = (urlencode($req->OrderDescription));
		$cvv2Number = urlencode($req->CCSecurityCode);
		$address1 = urlencode($req->CustomerStreetAddress);
		$address2 = urlencode($req->CustomerStreetAddress2);
		$city = urlencode($req->CustomerCity);
		$state = urlencode($req->CustomerState);
		$zip = urlencode($req->CustomerZipCode);
		$amount = urlencode($req->TransactionAmount);
		$currencyID = urlencode($req->TransactionCurrency);		// or other currency ('GBP', 'EUR', 'JPY', 'CAD', 'AUD')

		// soft descriptor can only be a max of 22 chars with no non-alphanumeric characters
		$softdescriptor = urlencode(substr(preg_replace("/[^a-zA-Z0-9\s]/", "", $req->SoftDescriptor),0,22 ));

		// legit country code list: https://cms.paypal.com/us/cgi-bin/?&cmd=_render-content&content_ID=developer/e_howto_api_nvp_country_codes
		$country = urlencode( strtoupper($req->CustomerCountry) );	// US or other valid country code
		if ($country == "USA") $country = "US";


		// Add request-specific fields to the request string.
		$nvpStr = "&PAYMENTACTION=$paymentType&AMT=$amount&CREDITCARDTYPE=$creditCardType&ACCT=$creditCardNumber".
					"&EXPDATE=$padDateMonth$expDateYear&CVV2=$cvv2Number&FIRSTNAME=$firstName&LASTNAME=$lastName".
					"&STREET=$address1&CITY=$city&STATE=$state&ZIP=$zip&COUNTRYCODE=$country&CURRENCYCODE=$currencyID".
					"&DESC=$orderDesc&INVNUM=$invoiceNum&EMAIL=$email&SOFTDESCRIPTOR=$softdescriptor";

		// make the post - use a try/catch in case of network errors
		try
		{
			$resp->RawResponse = $this->PPHttpPost('DoDirectPayment', $nvpStr);

			if ("SUCCESS" == strtoupper($resp->RawResponse["ACK"]) || "SUCCESSWITHWARNING" == strtoupper($resp->RawResponse["ACK"]))
			{
				$resp->IsSuccess = true;
				$resp->TransactionId = urldecode( $this->GetArrayVal($resp->RawResponse,"TRANSACTIONID") );
				$resp->ResponseCode = urldecode( "AVSCODE=" . $this->GetArrayVal($resp->RawResponse,"AVSCODE") . ",CVV2MATCH=" . $this->GetArrayVal($resp->RawResponse,"CVV2MATCH"));
				$resp->ResponseMessage = urldecode( "Charge of " . $this->GetArrayVal($resp->RawResponse,"AMT") . " Posted" );
			}
			else
			{
				// for error descriptions, refrer to https://cms.paypal.com/us/cgi-bin/?cmd=_render-content&content_ID=developer/e_howto_api_nvp_errorcodes
				$resp->IsSuccess = false;
				$resp->ResponseCode = urldecode( $this->GetArrayVal($resp->RawResponse,"L_ERRORCODE0") );
				$resp->ResponseMessage = $this->GetErrorMessage($resp->RawResponse);

			}

			$resp->ParsedResponse = "";
			$delim = "";
			foreach (array_keys($resp->RawResponse) as $key)
			{
				$resp->ParsedResponse .= $delim . $key . "='" . urldecode( $resp->RawResponse[$key]) . "'";
				$delim = ", ";
			}

		}
		catch (Exception $ex)
		{
			// this means we had a connection error talking to the gateway
			$resp->IsSuccess = false;
			$resp->ResponseCode = $ex->getCode();
			$resp->ResponseMessage = $ex->getMessage();
		}



		return $resp;
	}

	/**
	 * Given a response array, attempt to return the most sensible error message.
	 * @param array $httpParsedResponseAr
	 */
	private function GetErrorMessage($httpParsedResponseAr)
	{
		/* SAMPLE RETURN VALUE
		(
		    [TIMESTAMP] => 2012%2d03%2d23T01%3a47%3a01Z
		    [CORRELATIONID] => c9dcc0b7acd94
		    [ACK] => Failure
		    [VERSION] => 62%2e0
		    [BUILD] => 2649250
		    [L_ERRORCODE0] => 10507
		    [L_SHORTMESSAGE0] => Invalid%20Configuration
		    [L_LONGMESSAGE0] => This%20transaction%20cannot%20be%20processed%2e%20Please%20contact%20PayPal%20Customer%20Service%2e
		    [L_SEVERITYCODE0] => Error
		    [AMT] => 103%2e00
		    [CURRENCYCODE] => USD
		)
		*/

		$errmsg = $this->GetArrayVal($httpParsedResponseAr,"L_SHORTMESSAGE0") . ": ";

		// figure out the message as PayPal reports it
		$longmessage = $this->GetArrayVal($httpParsedResponseAr,"L_LONGMESSAGE0");

		// paypal prepends this to every message, so strip it out
		$longmessage = str_replace("This%20transaction%20cannot%20be%20processed%2e","", $longmessage );

		if ($longmessage != "")
		{
			// this will generally be the best description of the error
			$errmsg .= $longmessage;
		}
		else
		{
			// paypal didn't give a simple error description so we have to try to decipher the gateway response

			// this is the response code from the gateway
			$processor_code = $this->GetArrayVal($httpParsedResponseAr,"L_ERRORPARAMVALUE0");

			if ($processor_code)
			{
				// this will usually be "ProcessorResponse" in which case we don't need to display it
				$processor_prefix = $this->GetArrayVal($httpParsedResponseAr,"L_ERRORPARAMID0");
				$processor_prefix = ($processor_prefix == "ProcessorResponse")
				? ''
				: $processor_prefix . ' - ';

				$processor_message =  $processor_prefix . $this->getProcessorResponseDescription($processor_code);

				$errmsg .= $processor_message;
			}
		}

		return urldecode($errmsg);
	}

	/**
	 * Util to return array values without throwing an undefined error
	 *
	 * @param Array $arr
	 * @param variant $key
	 * @param variant $not_defined_val value to return if array key doesn't exist
	 * @return variant
	 */
	private function GetArrayVal($arr,$key,$not_defined_val = "")
	{
		return array_key_exists($key,$arr)
			? $arr[$key]
			: $not_defined_val;
	}


	/**
	 * Send HTTP POST Request.  Throws an Exception if the server communication failed
	 *
	 * @param	string	The API method name
	 * @param	string	The POST Message fields in &name=value pair format
	 * @return	array	Parsed HTTP Response body
	 */
	private function PPHttpPost($methodName_, $nvpStr_) {

		// Set up your API credentials, PayPal end point, and API version.
		$API_UserName = urlencode($this->Username);
		$API_Password = urlencode($this->Password);
		$API_Signature = urlencode($this->Signature);
		$API_Endpoint = "https://api-3t.paypal.com/nvp";

		if ("sandbox" === $this->environment || "beta-sandbox" === $this->environment)
		{
			$API_Endpoint = "https://api-3t." . $this->environment . ".paypal.com/nvp";
		}

		//$version = urlencode('51.0');
		$version = urlencode('62.0');

		// Set the curl parameters.
		$ch = curl_init();
		curl_setopt($ch, CURLOPT_URL, $API_Endpoint);
		curl_setopt($ch, CURLOPT_VERBOSE, 1);

		// Turn off the server and peer verification (TrustManager Concept).
		curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
		curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);

		curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
		curl_setopt($ch, CURLOPT_POST, 1);

		// Set the API operation, version, and API signature in the request.
		$nvpreq = "METHOD=$methodName_&VERSION=$version&PWD=$API_Password&USER=$API_UserName&SIGNATURE=$API_Signature$nvpStr_";

		// Set the request as a POST FIELD for curl.
		curl_setopt($ch, CURLOPT_POSTFIELDS, $nvpreq);

		// Get response from the server.
		$httpResponse = curl_exec($ch);

		if(!$httpResponse) {
			throw new Exception("$methodName_ failed: ".curl_error($ch).'('.curl_errno($ch).')');
		}

		// Extract the response details.
		$httpResponseAr = explode("&", $httpResponse);

		$httpParsedResponseAr = array();
		foreach ($httpResponseAr as $i => $value) {
			$tmpAr = explode("=", $value);
			if(sizeof($tmpAr) > 1) {
				$httpParsedResponseAr[$tmpAr[0]] = $tmpAr[1];
			}
		}

		if((0 == sizeof($httpParsedResponseAr)) || !array_key_exists('ACK', $httpParsedResponseAr)) {
			throw new Exception("Invalid HTTP Response for POST request($nvpreq) to $API_Endpoint.");
		}

		return $httpParsedResponseAr;
	}

	/**
	 * This returns a formatted error given a payment processor error response code.
	 *
	 * @link https://www.x.com/blogs/matt/2010/10/26/error-codes-explained-15005
	 * @param string $code
	 * @return string possible description of error
	 */
	private function getProcessorResponseDescription($code)
	{
		return "Transaction was rejected by the issuing bank with error code $code.";

		// @TODO these have proven to be unreliable, but maybe somebody can do something better?
		/*
		$responses = Array();
      	$responses['0005'] = "The transaction was declined without explanation by the card issuer.";
		$responses['0013'] = "The transaction amount is greater than the maximum the issuer allows.";
		$responses['0014'] = "The issuer indicates that this card is not valid.";
		$responses['0051'] = "The credit limit for this account has been exceeded.";
		$responses['0054'] = "The card is expired.";
		$responses['1015'] = "The credit card number was invalid.";
		$responses['1511'] = "Duplicate transaction attempt.";
		$responses['1899'] = "Timeout waiting for host response.";
		$responses['2075'] = "Approval from the card issuer's voice center is required to process this transaction.";

		return array_key_exists($code,$responses)
			? "Error Code " . $code . ": " .$responses[$code]
			: "Error Code " . $code;
		*/


	}

}

?>