$(document).ready(function(){

    $("#delivery_same_as_invoice").click(function(event){

      if($(this).is(":checked")) {
        populateDeliveryAddress();
      } else {
        clearDeliveryAddress();
      }
    });

    function populateDeliveryAddress() {
      $("#delivery_address_address1").val($("#invoice_address_address1").val());
      $("#delivery_address_address2").val($("#invoice_address_address2").val());
      $("#delivery_address_town").val($("#invoice_address_town").val());
      $("#delivery_address_county").val($("#invoice_address_county").val());
      $("#delivery_address_postcode").val($("#invoice_address_postcode").val());
    }
    function clearDeliveryAddress() {
      $(".right input:text").val('');
    }
  });