Working with PayPal IPN's malformatted multidimensional arrays

paypal_standards_suck.php

<?php

use PayPal\IPN\PPIPNMessage;

$postData = file_get_contents('php://input');

$ipn = new PPIPNMessage($postData);

if (!$ipn->validate()) {
	exit;
}

$data = array();
$fixArr = preg_replace("/\b(\w+)\\%5B(\w+)\\%5D\.([^=]*)[=]([^\&]*)([\&$])\b/", "$1%5B$2%5D%5B$3%5D=$4$5", $postData);
parse_str($fixArr, $data);

if (isset($data['payment_status'])) {
	$payment_status = $data['payment_status'];
	$txn_id = $data['txn_id'];
} else if ($data['transaction']) {
	foreach ($data['transaction'] as $transaction) {
		if ($transaction['is_primary_receiver'] === 'true') {
			$payment_status = $transaction['status'];
			$txn_id = $transaction['id'];
		}
	}
}