/**
     * Retrieve all addresses of a host by it's address. NetBIOS hosts can
     * have many names for a given IP address. The name and IP address make the
     * NetBIOS address. This provides a way to retrieve the other names for a
     * host with the same IP address.
     *
     * @param addr
     *            the address to query
     * @return resolved addresses
     * @throws UnknownHostException

   *
   * @param ip {@link Inet6Address} to be examined for embedded IPv4 in 6to4 address
   * @return {@link Inet4Address} of embedded IPv4 in 6to4 address
   * @throws IllegalArgumentException if the argument is not a valid IPv6 6to4 address
   */
  public static Inet4Address get6to4IPv4Address(Inet6Address ip) {

    val other = MockWebServer()
    val addressA = InetAddress.getByAddress("localhost", byteArrayOf(127, 0, 0, 1))
    val addressB = InetAddress.getByAddress("localhost", byteArrayOf(127, 0, 0, 2))
    other.use {
      other.start(addressA, 0)

      // Same address is okay.
      other.start(addressA, 0)

      // Same address with bound port is okay.
      other.start(addressA, other.port)

        assertNotNull(address, "Should return address for IP address");
        assertEquals("127.0.0.1", address.getHostAddress(), "Should return correct IP address");
    }

    @Test
    @DisplayName("Should get all addresses by name")
    void testGetAllByName() throws UnknownHostException {
        // When
        Address[] addresses = nameServiceClient.getAllByName("localhost", false);

        // Then

        // Given: Multiple addresses with different fail counts
        Address addr1 = mock(Address.class);
        when(addr1.getHostAddress()).thenReturn("10.0.0.1");

        Address addr2 = mock(Address.class);
        when(addr2.getHostAddress()).thenReturn("10.0.0.2");

        when(nameSvc.getAllByName(eq("test.server"), eq(true))).thenReturn(new Address[] { addr1, addr2 });

        NbtAddress[] addresses = new NbtAddress[2];
        // Create dummy NbtAddress objects for testing toString
        addresses[0] = new NbtAddress(mockRecordName, 0xC0A80101, false, 0); // 192.168.1.1
        addresses[1] = new NbtAddress(mockRecordName, 0x0A000005, true, 1); // 10.0.0.5
        addrEntryField.set(nameQueryResponse, addresses);

        String expectedContains = ",addrEntry=[";

/**
 * Implementation of HappyEyeballs Sorting Addresses.
 *
 * The current implementation does not address any of:
 *  - Async DNS split by IP class
 *  - Stateful handling of connectivity results
 *  - The prioritisation of addresses
 *
 * https://datatracker.ietf.org/doc/html/rfc8305#section-4
 */
internal fun reorderForHappyEyeballs(addresses: List<InetAddress>): List<InetAddress> {
  if (addresses.size < 2) {
    return addresses
  }

import okhttp3.Dns

/**
 * A network that always resolves two IP addresses per host. Use this when testing route selection
 * fallbacks to guarantee that a fallback address is available.
 */
class DoubleInetAddressDns : Dns {
  override fun lookup(hostname: String): List<InetAddress> {
    val addresses = Dns.SYSTEM.lookup(hostname)
    return listOf(addresses[0], addresses[0])
  }

 *  * **IP address:** whether connecting directly to an origin server or a proxy, opening a socket
 *    requires an IP address. The DNS server may return multiple IP addresses to attempt.
 *
 * Each route is a specific selection of these options.
 */
class Route(
  @get:JvmName("address") val address: Address,
  /**
   * Returns the [Proxy] of this route.
   *

    }

    static final class CacheEntry {

        Name hostName;
        NbtAddress address;
        long expiration;

        CacheEntry(final Name hostName, final NbtAddress address, final long expiration) {
            this.hostName = hostName;
            this.address = address;
            this.expiration = expiration;
        }
    }

    /**
     *
     */