import ipv4;
import dns;

let client = 192.168.238.112;
let server = 142.250.207.36;
let google = 8.8.8.8;

let dns = ipv4::udp::flow(
  client/13749,
  google/53,
);

# There is a low-level DNS API which you can use to construct exact queries,
# and even malformed queries
dns.client_dgram(
  dns::hdr(
    id: 0x1234,
    flags: dns::flags(
      opcode: dns::opcode::QUERY,
      rd: 1,
    ),
    qdcount: 1,
  ),
  dns::question(
    qname: dns::name("www", "google", "com"),
    qtype: dns::type::A,
    qclass: dns::class::IN,
  )
);

dns.server_dgram(
  dns::hdr(
    id: 0x1234,
    flags: dns::flags(
      response: 1,
      opcode: dns::opcode::QUERY,
      ra: 1,
    ),
    qdcount: 1,
    ancount: 1,
  ),
  dns::question(
    qname: dns::name("www", "google", "com"),
    qtype: dns::type::A,
    qclass: dns::class::IN,
  ),
  dns::answer(
    aname: dns::name("www", "google", "com"),
    atype: dns::type::A,
    aclass: dns::class::IN,
    server,
  ),
);

# And then there is the high level API which you can use to quickly generate a
# query/response pair to make it lool like our hosts are doing DNS lookups
dns::host(client, "www.google.com", ns: google, server);