Prestashop - Replace some char in zip code if a specific country is selected

Question

I need to change the postal code at the moment of the check out (the module is Onepagecheckout).

The target is to do a str_replace() of postal cose according to country of the address, before the data stored in wp_address. For exemple, if the country is Portugal, the zip code format is NNNN-NNN. I have to replace the "-" with "".

I found the hook that store the address in the DB, and the edit work nice. But there is a new problem: normally, when i select the conuntry, automatically the module show me some possibility of shipping and now that's not happen with the country where i edit the zip code.

The hook that provide store the address is Hook::exec('actionSubmitCustomerAddressForm', array('address' => &$address));, in the file onepagecheckoutps.php

For sure, there is a incompatibility with the zip_code_format in the table ww_ps_country, at some point he compare the zip_code_format (NNNN-NN) with the zip code (that will be NNNNNN).

But i don't know why i can fix this. Here my code in onepagecheckoutps.php => validateFieldsAddress()

    ...
if (!Validate::isDate($address->date_add)) {
        $address->date_add = date('Y-m-d H:i:s');
    }
    if (!Validate::isDate($address->date_upd)) {
        $address->date_upd = $address->date_add;
    }

    switch ($address->id_country) {
        case 15 :
            $address->postcode = str_replace("-","",$address->postcode);
        case 13:
            $address->postcode = substr($address->postcode,0,4);
        case 125:
            $address->postcode = substr($address->postcode,3);
        case 12:
            $address->postcode = substr($address->postcode,2);
    }

    Hook::exec('actionSubmitCustomerAddressForm', array('address' => &$address));
}

What i get:

What i should get: