<?php
// needs: https://github.com/VIISON/AddressSplitting

add_filter('pr_shipping_dhl_label_args', 'fix_dhl_address', 2, 10);

function split_address( $address_1, $address_2 ) {
  $split = array();
  // try to split the first adress line
  try {
    $split = \VIISON\AddressSplitter\AddressSplitter::splitAddress( $address_1 );
  } catch ( Exception $e ) {
    // try again with with added field
    try {
      $split = \VIISON\AddressSplitter\AddressSplitter::splitAddress( $address_1 . ' ' .
                                                                      $address_2 );
    // address is probably invalid
    } catch (Exception $e) {
      error_log($e->getMessage());
    }
  }
  return $split;
}

function fix_dhl_address($args, $order_id) {
  $split = $this->split_address($args['shipping_address']['address_1'], $args['shipping_address']['address_2']);

  if (!empty($split)) {
    $args['shipping_address']['address_1'] = $split['streetName'];
    $args['shipping_address']['address_2'] = $split['houseNumber'];
  } // TODO: handle empty case (invalid address?) or rely on DHL API to handle it?
  return $args;
}