function getShoppingCartSummary() {
	var mainElement;
	var summaryElement;
	
	mainElement = document.getElementById('display_cart_summary');
	
	if(mainElement == null) {
		return null;
	}

	return mainElement.innerHTML;	
}

/**
 * @return true, false, or null depending on if the cart is empty, not empty, or unknown
 */
function isShoppingCartEmpty() {
	var contents;
	
	contents = getShoppingCartSummary();
	
	if(contents == null) {
		return null;
	}

	if(contents.search('(Your shopping cart is empty)') != -1) {
		return true;
	}
	
	return false;
}

/**
 * 
 */
function getShoppingCartItems() {
	var summary;
	var result;

	summary = getShoppingCartSummary();
	
	if(summary == null) {
		return null;
	}
	
	result = summary.match(/\d+/);
	
	if(result == null) {
		return null;
	}
	
	return result[0];
}

/**
 * 
 */
function getShoppingCartTotal() {
	var summary;
	var result1;
	var result2;
	var output;

	summary = getShoppingCartSummary();
	
	if(summary == null) {
		return null;
	}
	
	//(Your shopping cart contains 1 item priced at $800.00) 
	//(Your shopping cart contains 2 items for a total cost of $920.00) 
	result1 = summary.match(/total\scost\sof\s.*\)/);
	result2 = summary.match(/priced\sat\s.*\)/);
	
	if(result1 == null && result2 == null) {
		return null;
	}
	
	if(result1 != null) {
		//total cost of text
		if(result1[0] == null || result1[0].length <= 15) {
			return null;
		}
		
		output = result1[0].substr(14, result1[0].length-15);
	}
	else {
		//priced at text
		if(result2[0] == null || result2[0].length <= 11) {
			return null;
		}
		
		output = result2[0].substr(10, result2[0].length-11);
	}
	
	return output;
}


function updateHeaderCartSummary() {
	var element;
	var items;
	var output;
	
	element = document.getElementById('view_cart_text_right');
	
	if(element == null) {
		return;
	}
	
	items = getShoppingCartItems();
	total = getShoppingCartTotal();
	
	//No items or null
	if(isShoppingCartEmpty()) {
		output = '0 Items: <b>$0.00</b>';
	}
	else if (items == null || total == null) {
		return;
	}
	else if(items == 0) {
		output = '0 Items: <b>$0.00</b>';
	}
	else {
		//Create string
		output = items + ' Item';
		if (items > 1) {
			output = output + 's';
		}
		output = output + ': <b>' + total + '</b>';
	}
	
	//Put data into field
	element.innerHTML = output;
}