// For both order complete and ship

<?php $orderId = 100000821; // you're order Id
gaOrderCompShip($orderId); // define function

  function gaOrderCompShip($orderId){   // function definition
        $email = true;   
        $trackingNum = '';
        $carrier = 'custom';
        $includeComment = false;
        $comment = "Order Completed And Shipped";

        $order = Mage::getModel('sales/order')->loadByIncrementId($orderId);

     
        $convertor = Mage::getModel('sales/convert_order');
        $shipment = $convertor->toShipment($order);

        foreach ($order->getAllItems() as $orderItem) {
         
            if (!$orderItem->getQtyToShip()) {
                continue;
            }
            if ($orderItem->getIsVirtual()) {
                continue;
            }
            $item = $convertor->itemToShipmentItem($orderItem);
            $qty = $orderItem->getQtyToShip();
            $item->setQty($qty);
            $shipment->addItem($item);
        }

        $carrierTitle = NULL;

        if ($carrier == 'custom') {
            $carrierTitle = 'courier Service name';
        }
        $data = array();
        $data['carrier_code'] = $carrier;
        $data['title'] = $carrierTitle;
        $data['number'] = $trackingNum;

        $track = Mage::getModel('sales/order_shipment_track')->addData($data);
        $shipment->addTrack($track);

        $shipment->register();
        $shipment->addComment($comment, $email && $includeComment);
        $shipment->setEmailSent(true);
        $shipment->getOrder()->setIsInProcess(true);

        $transactionSave = Mage::getModel('core/resource_transaction')
            ->addObject($shipment)
            ->addObject($shipment->getOrder())
            ->save();

        $shipment->sendEmail($email, ($includeComment ? $comment : ''));
        $order->setStatus('Complete');
        $order->addStatusToHistory($order->getStatus(), $comment, false);
     
        $shipment->save();
} ?>

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