Showing full country name, rather than country code

Trying to use <?php echo $current_user->billing_country; ?> to display the Woocommerce user billing country. This for example echo’s as AU if the customer has an Australian billing address. However, I would like to pull the full name in place of the country code.

The same applies for the billing_state. Instead of getting South Australia I get SA. Have made work through functions.php, however only if I add each state and country. This is obviously a great undertaking to map the worlds states to the state codes.

I believe I have done this before in a very simple way, but for whatever reason cannot figure it out at this moment.

The country and state are being used within a disable input field as the value
<input type="text" class="form-control" value="<?php echo $current_user->billing_country; ?>" disabled="">

Cheers