cheque module modification

[opionai]

How can I collect the id_order variable to send it with the confirmation email of the cheque module but with base64_encode encoded (
        

$mailVars =    array(
            '{cheque_name}' => Configuration::get('CHEQUE_NAME'),
            '{cheque_address}' => Configuration::get('CHEQUE_ADDRESS'),
            '{cheque_address_html}' => str_replace("\n", '<br />', Configuration::get('CHEQUE_ADDRESS')),
            {id_order} =>  here
            );

        $this->module->validateOrder((int)$cart->id, Configuration::get('PS_OS_CHEQUE'), $total, $this->module->displayName, NULL, $mailVars, (int)$currency->id, false, $customer->secure_key);
        Tools::redirect('index.php?controller=order-confirmation&id_cart='.(int)$cart->id.'&id_module='.(int)$this->module->id.'&id_order='.$this->module->currentOrder.'&key='.$customer->secure_key);
    }
}

 

 

Como puedo recoger la variable de id_order para enviarla con el email  de confirmación del modulo cheque pero con codificada base64_encode(

 

$mailVars =    array(
            '{cheque_name}' => Configuration::get('CHEQUE_NAME'),
            '{cheque_address}' => Configuration::get('CHEQUE_ADDRESS'),
            '{cheque_address_html}' => str_replace("\n", '<br />', Configuration::get('CHEQUE_ADDRESS')),
            {id_order} =>  aqui
            );

        $this->module->validateOrder((int)$cart->id, Configuration::get('PS_OS_CHEQUE'), $total, $this->module->displayName, NULL, $mailVars, (int)$currency->id, false, $customer->secure_key);
        Tools::redirect('index.php?controller=order-confirmation&id_cart='.(int)$cart->id.'&id_module='.(int)$this->module->id.'&id_order='.$this->module->currentOrder.'&key='.$customer->secure_key);
    }
}

[opionai]

Please help me