Credit Card Validation

credit_card_validate.php

<?php
 function checkSum($ccnum) {
	$checksum = 0;
	for ($i=(2-(strlen($ccnum) % 2)); $i<=strlen($ccnum); $i+=2)
	{
		$checksum += (int)($ccnum{$i-1});
	}
	for ($i=(strlen($ccnum)% 2) + 1; $i<strlen($ccnum); $i+=2) 
	{
		$digit = (int)($ccnum{$i-1}) * 2;
		if ($digit < 10) { 
			$checksum += $digit; 
		}
		else { 
			$checksum += ($digit-9); 
		}
	}
	if (($checksum % 10) == 0) 
		return true; 
	else 
		return 0;
}


function checkExpDate($month,$year) {
	$expTs = mktime(0, 0, 0, $month + 1, 1, $year);
	$curTs = time();
	$maxTs = $curTs + (10 * 365 * 24 * 60 * 60);
	if ($expTs > $curTs && $expTs < $maxTs) {
		return true;
	} else {
		return 0;			
	}
}

function validateCVV($type,$cvv) {
	$count = ($type === 'amex') ? 4 : 3;
	if(preg_match('/^[0-9]{'.$count.'}$/', $cvv)) {
		return true;
	}else { 
	   return 0;
	} 
}

function isValidCardNumber($cardNumber,$month,$year,$cvv) {
	$creditcard = array(  "Visa"=>"/^4\d{3}-?\d{4}-?\d{4}-?\d{4}$/",
					"Mastercard"=>"/^5[1-5]\d{2}-?\d{4}-?\d{4}-?\d{4}$/",
					"Discover"=>"/^6011-?\d{4}-?\d{4}-?\d{4}$/",
					"Amex"=>"/^3[4,7]\d{13}$/",
					//"diners"=>"/^3[0,6,8]\d{12}$/",
					//"bankcard"=>"/^5610-?\d{4}-?\d{4}-?\d{4}$/",
					//"jcb"=>"/^[3088|3096|3112|3158|3337|3528]\d{12}$/",
					//"enroute"=>"/^[2014|2149]\d{11}$/",
					"Switch"=>"/^[4903|4911|4936|5641|6333|6759|6334|6767]\d{12}$/");
					$match=false;
	foreach($creditcard as $type=>$pattern) {
		if(preg_match($pattern,$cardNumber) === 1) {
			$match=true;
			$cardType = $type;
			break;
		}
	}
	
	if(!$match) {
		//return "Invalid card number. Please check credit card number";			
		return "Fail";
	}
	else {	
		if((checkSum($cardNumber)==true) and (checkExpDate($month,$year)==true) and (validateCVV($cardType,$cvv)==true)){
			return "Success";
		}else{
			return "Fail";
		}
	}	
}

function isValidCardType($cardNumber) {
	$creditcard = array(  "Visa"=>"/^4\d{3}-?\d{4}-?\d{4}-?\d{4}$/",
					"Mastercard"=>"/^5[1-5]\d{2}-?\d{4}-?\d{4}-?\d{4}$/",
					"Discover"=>"/^6011-?\d{4}-?\d{4}-?\d{4}$/",
					"Amex"=>"/^3[4,7]\d{13}$/",
					//"diners"=>"/^3[0,6,8]\d{12}$/",
					//"bankcard"=>"/^5610-?\d{4}-?\d{4}-?\d{4}$/",
					//"jcb"=>"/^[3088|3096|3112|3158|3337|3528]\d{12}$/",
					//"enroute"=>"/^[2014|2149]\d{11}$/",
					"Switch"=>"/^[4903|4911|4936|5641|6333|6759|6334|6767]\d{12}$/");
	$match=false;
	foreach($creditcard as $type=>$pattern) {
		if(preg_match($pattern,$cardNumber) === 1) {
			$match=true;
			$cardType = $type;
			break;
		}
	}
	
	if(!$match) {
		//return "Invalid card number. Please check credit card number";			
		return "Plain";
	}
	else {	
		return $cardType;
	}	
}
	
$validation_type = (@$_GET['vtype']) ? : die("Invalid Type");
$credit_card_number = (@$_GET['cval']) ? : die("Plain");
$month = (@$_GET['month']) ? : "0";
$months = explode("/", $month);
$cvv = (@$_GET['cvv']) ? : "0";

if ($validation_type == 'full'){
	echo isValidCardNumber($credit_card_number,$months[0],$months[1],$cvv);
}else{
	echo isValidCardType($credit_card_number);
}
?>