Invoices For Each Shop

[garciasanchezdani]

I have a prestashop website, which has two shops ( multi-store): shop 'A', and shop 'B'.

When I buy only products from shop A, invoice is generated properly, with data of shop A; and vice versa.

But my problem comes when I buy one product from shop A, and other product from shop B. Then, the invoice is generated with only data of one shop ( shop A, which is the default ).

I'd need to display both shops in the invoice ( in the same pdf ).

My template is invoice, so the tpl is invoice.tpl ( and header.tpl and footer.tpl ), and I see that the file classes/pdf/HTMLTemplateInvoice.php do the logic:

public function __construct(OrderInvoice $order_invoice, $smarty)
    {
        $this->order_invoice = $order_invoice;
        $this->order = new Order((int)$this->order_invoice->id_order);
        $this->smarty = $smarty;

        // header informations
        $this->date = Tools::displayDate($order_invoice->date_add);

        $id_lang = Context::getContext()->language->id;
        $prefix = Configuration::get('PS_INVOICE_PREFIX', $id_lang, null, (int)$this->order->id_shop);
        $this->title = sprintf(HTMLTemplateInvoice::l('Invoice #%1$s%2$06d'), $prefix, $order_invoice->number);
        // footer informations
        $this->shop = new Shop((int)$this->order->id_shop);
    }

Could you help me, please?