<?php
/* This macro will be parsed as PHP code (see http://www.php.net)

The calculateshipping function is called every time a shipping calculation request is made by Shopify.

The function must return an array of available shipping options, otherwise no shipping options will be returned to your customers.
*/
function calculateshipping($DATA) {

	/* do not edit above this line */

	$_RATES = array();

	//this will detect items with $0 as items requiring shipping

	$ratePerItem = 10;
	
	$rate = 0;
	foreach ($DATA['items'] as $item) {
		if ($item['price'] == 0) {
			//this is a free item and therefore requires shipping
			$rate += $ratePerItem*$item['quantity'];
		}
	}

	$_RATES[] = array(
		"service_name" => "Standard Shipping",
		"service_code" => "STANDARD",
		"total_price" => $rate*100, //in cents
		"currency" => "USD",
	);

	return $_RATES;

	/* do not edit below this line */

}