Magento - Grand Total To Be Charged on Invoice

When a customer buys something from a Magento store they receive an email confirmation which includes a line at the bottom for "Grand Total To Be Charged". This shows the total in the stores base currency.

I would like to add this figure to the invoices which get printed from开发者_JAVA技巧 the backend. How can this be done?

Lets see what is going on. As we can see from the url (www.example.com/index.php/admin/sales_invoice/view/invoice_id/[some_id]/) Mage_Adminhtml_Sales_Order_InvoiceController's view action is executed and this is corresponds to <adminhtml_sales_order_invoice_view> layout (app/design/adminhtml/default/default/layout/sales.xml) node. There we can see this:

<adminhtml_sales_order_invoice_view>
        <reference name="content">
            <block type="adminhtml/sales_order_invoice_view" name="sales_invoice_view">
...

We can see there that top block is Mage_Adminhtml_Block_Sales_Order_Invoice_View. There we can see (at the end of __construct() method):

if ($this->getInvoice()->getId()) {
    $this->_addButton('print', array(
        'label'     => Mage::helper('sales')->__('Print'),
        'class'     => 'save',
        'onclick'   => 'setLocation(\''.$this->getPrintUrl().'\')'
        )
    );
}

and

public function getPrintUrl()
{
    return $this->getUrl('*/*/print', array(
        'invoice_id' => $this->getInvoice()->getId()
    ));
}

Here we can see that our invoice PDF is created from a print action of current module/controller so lets see Mage_Adminhtml_Sales_Order_InvoiceController again and search for a required action method:

/**
 * Create pdf for current invoice
 */
public function printAction()
{
    $this->_initInvoice();
    parent::printAction();
}

and in parent Mage_Adminhtml_Controller_Sales_Invoice:

public function printAction()
{
    if ($invoiceId = $this->getRequest()->getParam('invoice_id')) {
        if ($invoice = Mage::getModel('sales/order_invoice')->load($invoiceId)) {
            $pdf = Mage::getModel('sales/order_pdf_invoice')->getPdf(array($invoice));
            $this->_prepareDownloadResponse('invoice'.Mage::getSingleton('core/date')->date('Y-m-d_H-i-s').
                '.pdf', $pdf->render(), 'application/pdf');
        }
    }
    else {
        $this->_forward('noRoute');
    }
}

As we can see the PDF is created by sales/order_pdf_invoice model (or Mage_Sales_Model_Order_Pdf_Invoice class). Inside of a getPdf() method is a call $this->insertTotals($page, $invoice); which is defined in Mage_Sales_Model_Order_Pdf_Abstract class. My suggestion is to overwrite Mage_Sales_Model_Order_Pdf_Invoice class and define there a custom insertTotals($page, $invoice) method to achieve what you need. I decided to give a full picture of the situation to let you decide how to solve this task.

Useful link - Overriding a model class in Magento

In short all you need to do is add some XML:

<global>
    <pdf>
       <totals>
            <mygrand_total translate="title">
                <title>Grand Total To Be Charged</title>
                <source_field>base_grand_total</source_field>
                <font_size>8</font_size>
                <display_zero>1</display_zero>
                <sort_order>705</sort_order>
            </mygrand_total>
       </totals>
    </pdf>
</global>

I would create a separate module under app/code/local/Yourcompanyname/PDFBasetotal and enable the module via etc/modules/ after which create a config.xml file under Yourcompanyname/PDFBasetotal/etc/ here I would add the above XML as to avoid any touching of core functionality.

As to why this works see the method below from the file: app/code/core/Mage/Sales/Model/Order/Pdf/Abstract.php

Note the $totals = Mage::getConfig()->getNode('global/pdf/totals')->asArray(); as this is what is looped over when creating the total output.

protected function _getTotalsList($source)
{
    $totals = Mage::getConfig()->getNode('global/pdf/totals')->asArray();
    usort($totals, array($this, '_sortTotalsList'));
    $totalModels = array();
    foreach ($totals as $index => $totalInfo) {
        if (!empty($totalInfo['model'])) {
            $totalModel = Mage::getModel($totalInfo['model']);
            if ($totalModel instanceof Mage_Sales_Model_Order_Pdf_Total_Default) {
                $totalInfo['model'] = $totalModel;
            } else {
                Mage::throwException(
                    Mage::helper('sales')->__('PDF total model should extend Mage_Sales_Model_Order_Pdf_Total_Default')
                );
            }
        } else {
            $totalModel = Mage::getModel($this->_defaultTotalModel);
        }
        $totalModel->setData($totalInfo);
        $totalModels[] = $totalModel;
    }

    return $totalModels;
}