Here it is if someone is looking for something like this added more fields to echo to payment gateway
<?php
if (isset($_POST) && is_array($_POST) && count($_POST))
{
$loginID = "xxxxxxxxxxxxx";
$transactionKey = "xxxxxxxxxxxxxxxxx";
$description = "xxxxxxxxxxxxxxx";
$testMode = "false";
$amount = ($_REQUEST["x_amount"]);
$first_name = ($_POST["x_first_name"]);
$last_name = ($_POST["x_last_name"]);
$Address = ($_REQUEST["x_address"]);
$city = ($_REQUEST["x_city"]);
$state = ($_REQUEST["x_state"]);
$zip = ($_REQUEST["x_zip"]);
$email = ($_REQUEST["x_email"]);
$phone = ($_REQUEST["x_phone"]);
$invoice = date(YmdHis);
$sequence = rand(1, 1000);
$timeStamp = time();
// The following lines generate the SIM fingerprint. PHP versions 5.1.2 and
// newer have the necessary hmac function built in. For older versions, it
// will try to use the mhash library.
if( phpversion() >= '5.1.2' )
{
$fingerprint = hash_hmac("md5", $loginID . "^" . $sequence . "^" . $timeStamp . "^" . $amount ."^", $transactionKey);
}
else
{
$fingerprint = bin2hex(mhash(MHASH_MD5, $loginID . "^" . $sequence . "^" . $timeStamp . "^" . $amount . "^", $transactionKey));
}
?>
<form method="post" action="https://test.authorize.net/gateway/transact.dll"><input value="<?php echo $loginID; ?>" type="hidden" name="x_login" /> <input value="<?php echo $amount; ?>" type="hidden" name="x_amount" /> <input value="<?php echo $first_name; ?>" type="hidden" name="x_first_name" /> <input value="<?php echo $last_name; ?>" type="hidden" name="x_last_name" /> <input value="<?php echo $Address; ?>" type="hidden" name="x_address" /> <input value="<?php echo $city; ?>" type="hidden" name="x_city" /> <input value="<?php echo $state; ?>" type="hidden" name="x_state" /> <input value="<?php echo $zip; ?>" type="hidden" name="x_zip" /> <input value="<?php echo $description; ?>" type="hidden" name="x_description" /><input value="<?php echo $email; ?>" type="hidden" name="x_email" /><input value="<?php echo $phone; ?>" type="hidden" name="x_phone" /> <input value="<?php echo $invoice; ?>" type="hidden" name="x_invoice_num" /> <input value="<?php echo $sequence; ?>" type="hidden" name="x_fp_sequence" /> <input value="<?php echo $timeStamp; ?>" type="hidden" name="x_fp_timestamp" /> <input value="<?php echo $fingerprint; ?>" type="hidden" name="x_fp_hash" /> <input value="<?php echo $testMode; ?>" type="hidden" name="x_test_request" /> <input value="PAYMENT_FORM" type="hidden" name="x_show_form" /> <input value="Continue to Our Secure Server" type="submit" /> </form><?php
}
else
{
?>
<form method="post" action="<?php echo $_SERVER['PHP_SELF']; ?>">
<p>Amount: <input type="text" name="x_amount" /> </p>
<div>First Name: <input value="<?php echo $first_name; ?>" type="text" name="x_first_name" /> </div>
<div>Last Name: <input value="<?php echo $last_name; ?>" type="text" name="x_last_name" /> </div>
<div>Address: <input value="<?php echo $address; ?>" type="text" name="x_address" /> </div>
<div>city: <input value="<?php echo $city; ?>" type="text" name="x_city" /></div>
<div>state: <input value="<?php echo $state; ?>" type="text" name="x_state" /></div>
<div> zip: <input value="<?php echo $zip; ?>" type="text" name="x_zip" />
<div>Email: <input value="<?php echo $email; ?>" type="text" name="x_email" /> </div>
<div>Phone Number: <input value="<?php echo $phone; ?>" type="text" name="x_phone" /> <input value="NexT Page" type="submit" /> </div></form><?php
}
?> </div>