<?php

function encrypt_e($input, $ky) {
	$key   = html_entity_decode($ky);
	$iv = "@@@@&&&&####$$$$";
	$data = openssl_encrypt ( $input , "AES-128-CBC" , $key, 0, $iv );
	return $data;
}

function decrypt_e($crypt, $ky) {
	$key   = html_entity_decode($ky);
	$iv = "@@@@&&&&####$$$$";
	$data = openssl_decrypt ( $crypt , "AES-128-CBC" , $key, 0, $iv );
	return $data;
}

function generateSalt_e($length) {
	$random = "";
	srand((double) microtime() * 1000000);

	$data = "AbcDE123IJKLMN67QRSTUVWXYZ";
	$data .= "aBCdefghijklmn123opq45rs67tuv89wxyz";
	$data .= "0FGH45OP89";

	for ($i = 0; $i < $length; $i++) {
		$random .= substr($data, (rand() % (strlen($data))), 1);
	}

	return $random;
}

function checkString_e($value) {
	if ($value == 'null')
		$value = '';
	return $value;
}

function getChecksumFromArray($arrayList, $key, $sort=1) {
	if ($sort != 0) {
		ksort($arrayList);
	}
	$str = getArray2Str($arrayList);
	$salt = generateSalt_e(4);
	$finalString = $str . "|" . $salt;
	$hash = hash("sha256", $finalString);
	$hashString = $hash . $salt;
	$checksum = encrypt_e($hashString, $key);
	return $checksum;
}
function getChecksumFromString($str, $key) {
	
	$salt = generateSalt_e(4);
	$finalString = $str . "|" . $salt;
	$hash = hash("sha256", $finalString);
	$hashString = $hash . $salt;
	$checksum = encrypt_e($hashString, $key);
	return $checksum;
}

function verifychecksum_e($arrayList, $key, $checksumvalue) {
	$arrayList = removeCheckSumParam($arrayList);
	ksort($arrayList);
	$str = getArray2StrForVerify($arrayList);
	$paytm_hash = decrypt_e($checksumvalue, $key);
	$salt = substr($paytm_hash, -4);

	$finalString = $str . "|" . $salt;

	$website_hash = hash("sha256", $finalString);
	$website_hash .= $salt;

	$validFlag = "FALSE";
	if ($website_hash == $paytm_hash) {
		$validFlag = "TRUE";
	} else {
		$validFlag = "FALSE";
	}
	return $validFlag;
}

function verifychecksum_eFromStr($str, $key, $checksumvalue) {
	$paytm_hash = decrypt_e($checksumvalue, $key);
	$salt = substr($paytm_hash, -4);

	$finalString = $str . "|" . $salt;

	$website_hash = hash("sha256", $finalString);
	$website_hash .= $salt;

	$validFlag = "FALSE";
	if ($website_hash == $paytm_hash) {
		$validFlag = "TRUE";
	} else {
		$validFlag = "FALSE";
	}
	return $validFlag;
}

function getArray2Str($arrayList) {
	$findme   = 'REFUND';
	$findmepipe = '|';
	$paramStr = "";
	$flag = 1;	
	foreach ($arrayList as $key => $value) {
		$pos = strpos($value, $findme);
		$pospipe = strpos($value, $findmepipe);
		if ($pos !== false || $pospipe !== false) 
		{
			continue;
		}
		
		if ($flag) {
			$paramStr .= checkString_e($value);
			$flag = 0;
		} else {
			$paramStr .= "|" . checkString_e($value);
		}
	}
	return $paramStr;
}

function getArray2StrForVerify($arrayList) {
	$paramStr = "";
	$flag = 1;
	foreach ($arrayList as $key => $value) {
		if ($flag) {
			$paramStr .= checkString_e($value);
			$flag = 0;
		} else {
			$paramStr .= "|" . checkString_e($value);
		}
	}
	return $paramStr;
}

function redirect2PG($paramList, $key) {
	$hashString = getchecksumFromArray($paramList);
	$checksum = encrypt_e($hashString, $key);
}

function removeCheckSumParam($arrayList) {
	if (isset($arrayList["CHECKSUMHASH"])) {
		unset($arrayList["CHECKSUMHASH"]);
	}
	return $arrayList;
}

function getTxnStatus($requestParamList) {
	return callAPI(PAYTM_STATUS_QUERY_URL, $requestParamList);
}

function getTxnStatusNew($requestParamList,$PAYTM_STATUS_QUERY_NEW_URL) {
	return callNewAPI($PAYTM_STATUS_QUERY_NEW_URL, $requestParamList);
}

function initiateTxnRefund($requestParamList) {
	$CHECKSUM = getRefundChecksumFromArray($requestParamList,PAYTM_MERCHANT_KEY,0);
	$requestParamList["CHECKSUM"] = $CHECKSUM;
	return callAPI(PAYTM_REFUND_URL, $requestParamList);
}

function callAPI($apiURL, $requestParamList) {
	$jsonResponse = "";
	$responseParamList = array();
	$JsonData =json_encode($requestParamList);
	$postData = 'JsonData='.urlencode($JsonData);
	$ch = curl_init($apiURL);
	curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");                                                                     
	curl_setopt($ch, CURLOPT_POSTFIELDS, $postData);                                                                  
	curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); 
	curl_setopt ($ch, CURLOPT_SSL_VERIFYHOST, 0);
	curl_setopt ($ch, CURLOPT_SSL_VERIFYPEER, 0);
	curl_setopt($ch, CURLOPT_HTTPHEADER, array(                                                                         
	'Content-Type: application/json', 
	'Content-Length: ' . strlen($postData))                                                                       
	);  
	$jsonResponse = curl_exec($ch);   
	$responseParamList = json_decode($jsonResponse,true);
	return $responseParamList;
}

function callNewAPI($apiURL, $requestParamList) {
	$jsonResponse = "";
	$responseParamList = array();
	$JsonData =json_encode($requestParamList);
	$postData = 'JsonData='.urlencode($JsonData);
	$ch = curl_init($apiURL);
	curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");                                                                     
	curl_setopt($ch, CURLOPT_POSTFIELDS, $postData);                                                                  
	curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); 
	curl_setopt ($ch, CURLOPT_SSL_VERIFYHOST, 0);
	curl_setopt ($ch, CURLOPT_SSL_VERIFYPEER, 0);
	curl_setopt($ch, CURLOPT_HTTPHEADER, array(                                                                         
	'Content-Type: application/json', 
	'Content-Length: ' . strlen($postData))                                                                       
	);  
	$jsonResponse = curl_exec($ch);   
	$responseParamList = json_decode($jsonResponse,true);
	return $responseParamList;
}
function getRefundChecksumFromArray($arrayList, $key, $sort=1) {
	if ($sort != 0) {
		ksort($arrayList);
	}
	$str = getRefundArray2Str($arrayList);
	$salt = generateSalt_e(4);
	$finalString = $str . "|" . $salt;
	$hash = hash("sha256", $finalString);
	$hashString = $hash . $salt;
	$checksum = encrypt_e($hashString, $key);
	return $checksum;
}
function getRefundArray2Str($arrayList) {	
	$findmepipe = '|';
	$paramStr = "";
	$flag = 1;	
	foreach ($arrayList as $key => $value) {		
		$pospipe = strpos($value, $findmepipe);
		if ($pospipe !== false) 
		{
			continue;
		}
		
		if ($flag) {
			$paramStr .= checkString_e($value);
			$flag = 0;
		} else {
			$paramStr .= "|" . checkString_e($value);
		}
	}
	return $paramStr;
}
function callRefundAPI($refundApiURL, $requestParamList) {
	$jsonResponse = "";
	$responseParamList = array();
	$JsonData =json_encode($requestParamList);
	$postData = 'JsonData='.urlencode($JsonData);
	$ch = curl_init($apiURL);	
	curl_setopt ($ch, CURLOPT_SSL_VERIFYHOST, 0);
	curl_setopt ($ch, CURLOPT_SSL_VERIFYPEER, 0);
	curl_setopt($ch, CURLOPT_URL, $refundApiURL);
	curl_setopt($ch, CURLOPT_POST, true);
	curl_setopt($ch, CURLOPT_POSTFIELDS, $postData);  
	curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); 
	$headers = array();
	$headers[] = 'Content-Type: application/json';
	curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);  
	$jsonResponse = curl_exec($ch);   
	$responseParamList = json_decode($jsonResponse,true);
	return $responseParamList;
}


function pgRedirect($param){
	header("Pragma: no-cache");
	header("Cache-Control: no-cache");
	header("Expires: 0");

	if(!empty($param)){

		$checkSum = "";
		$paramList = array();


		// Create an array having all required parameters for creating checksum.
		$paramList["MID"] 				= $param['mid'];
		$paramList["ORDER_ID"] 			= $param["order_id"];
		$paramList["CUST_ID"] 			= $param["cust_id"];
		$paramList["INDUSTRY_TYPE_ID"] 	= $param['industry_type_id'];
		$paramList["CHANNEL_ID"] 		= $param['channel_id'];
		$paramList["TXN_AMOUNT"] 		= $param["txn_amount"];
		$paramList["WEBSITE"] 			= $param['mwebsite'];
		$paramList["CALLBACK_URL"] 		= $param['callback'];

		/*$paramList["MSISDN"] = $MSISDN; //Mobile number of customer
		$paramList["EMAIL"] = $EMAIL; //Email ID of customer
		$paramList["VERIFIED_BY"] = "EMAIL"; //
		$paramList["IS_USER_VERIFIED"] = "YES"; //

		*/

		//print_obj($paramList);die;

		//Here checksum string will return by getChecksumFromArray() function.
		$checkSum = getChecksumFromArray($paramList,$param['mkey']);

		//print_obj($checkSum);die;

		?>
		<center><h1>Please do not refresh this page...</h1></center>
		<form method="post" action="<?php echo $param['txn_url']; ?>" name="f1" id="f1">
			<?php
			foreach($paramList as $name => $value) {
				echo '<input type="hidden" name="'. $name .'" value="' . $value . '" id="'. $name .'">';
			}
			?>
			<input type="hidden" name="CHECKSUMHASH" id="CHECKSUMHASH" value="<?php echo $checkSum; ?>">
		</form>
		<?php
	}else{
		return 'Prameters are empty';
	}		
}


function pgResponse($param){
	// header("Pragma: no-cache");
	// header("Cache-Control: no-cache");
	// header("Expires: 0");

	//return $param;die;

	if(!empty($param)){
		$paytmChecksum = "";
		$paramList = array();
		$isValidChecksum = "FALSE";


		// // In Test Page, we are taking parameters from POST request. In actual implementation these can be collected from session or DB. 
		// $ORDER_ID = $_POST["ORDERID"];

		// // Create an array having all required parameters for status query.
		// $requestParamList = array("MID" => $param['mid'] , "ORDERID" => $ORDER_ID);  
		
		// $StatusCheckSum = getChecksumFromArray($requestParamList,$param['mkey']);
		
		// $requestParamList['CHECKSUMHASH'] = $StatusCheckSum;

		// // Call the PG's getTxnStatusNew() function for verifying the transaction status.
		// $responseParamList = getTxnStatusNew($requestParamList);

		// return $responseParamList;

		$paramList = $_POST;
		$paytmChecksum = isset($_POST["CHECKSUMHASH"]) ? $_POST["CHECKSUMHASH"] : ""; //Sent by Paytm pg

		//Verify all parameters received from Paytm pg to your application. Like MID received from paytm pg is same as your application’s MID, TXN_AMOUNT and ORDER_ID are same as what was sent by you to Paytm PG for initiating transaction etc.
		$isValidChecksum = verifychecksum_e($paramList, $param['mkey'], $paytmChecksum); //will return TRUE or FALSE string.

		if($isValidChecksum == "TRUE"){

			if ($_POST["STATUS"] == "TXN_SUCCESS"){
				if (isset($_POST["ORDERID"]) && $_POST["ORDERID"] != ""){
					// In Test Page, we are taking parameters from POST request. In actual implementation these can be collected from session or DB. 
					$ORDER_ID = $_POST["ORDERID"];

					// Create an array having all required parameters for status query.
					$requestParamList = array("MID" => $param['mid'] , "ORDERID" => $ORDER_ID);  
					
					$StatusCheckSum = getChecksumFromArray($requestParamList,$param['mkey']);
					
					$requestParamList['CHECKSUMHASH'] = $StatusCheckSum;

					// Call the PG's getTxnStatusNew() function for verifying the transaction status.
					$responseParamList = getTxnStatusNew($requestParamList,$param['paytm_status_query_new_url']);

					if (isset($responseParamList) && count($responseParamList)>0 ){
						$return=$responseParamList;
					}else{
						$return='Paytm Response error';
					}
				}else{
					$return='No Order ID Found';
				}
			}else{
				$return='Transaction Failed';
			}

		}else{
			$return='Checksum mismatched';
		}
	}else{
		$return='Parameter is empty';
	}	

	return $return;
}