Magento - submit invoice event and price comparison

Question

all!

I'm trying to compare prices, in Order, such as GrandTotal and TotalPaid, after submit invoice. i'm try listen "sales_order_invoice_save_after" event.

config.xml
...
<events>
    <sales_order_invoice_save_after>
        <observers>
            <orderapi>
                <class>orderapi/observer</class>
                <method>checkInvoiceSubmit</method>
            </orderapi>
        </observers>
    </sales_order_invoice_save_after>
</event>
...

and next step:

Observer.php
 public function checkInvoiceSubmit(Varien_Event_Observer $observer)
 {
    $event = $observer->getEvent()->getInvoice();
$paid = $event->getState();
        if($paid == 2) {
        echo $paid."<br/>";
     }
    var_dump("Grand ".$event->getGrandTotal());
    var_dump("Paid ".$event->getTotalPaid());
    var_dump("Due ".$event->getTotalDue());
    var_dump("Refunden "$event->getTotalRefunden());

    die;
}

and see: Grand 89.97, Paid NULL, DUE NULL, Refunden NULL.

input: Grand Total £89.97, Total Paid £0.00, Total Refunded £0.00, Total Due £89.97.

How do I properly compare the two prices(Grand and Total) after confirmation of payment?

Answer 1

Solution is:

$event = $observer->getEvent()->getInvoice()->getOrder();

Enjoy!