import ./make-test-python.nix (
  {
    nodes = {
      router = {config, pkgs, ...}: {
        config = {
          # This machine simulates a router with IPv6 forwarding and a static IPv6 address.
          boot.kernel.sysctl = {
            "net.ipv6.conf.all.forwarding" = true;
          };
          networking.interfaces.eth1 = {
            ipv6.addresses = [ { address = "fd00:dead:beef:dead::1"; prefixLength = 64; } ];
          };
          services.corerad = {
            enable = true;
            # Serve router advertisements to the client machine with prefix information matching
            # any IPv6 /64 prefixes configured on this interface.
            #
            # This configuration is identical to the example in the CoreRAD NixOS module.
            settings = {
              interfaces = [
                {
                  name = "eth0";
                  monitor = true;
                }
                {
                  name = "eth1";
                  advertise = true;
                  prefix = [{ prefix = "::/64"; }];
                }
              ];
              debug = {
                address = "localhost:9430";
                prometheus = true;
              };
            };
          };
        };
      };
      client = {config, pkgs, ...}: {
        # Use IPv6 SLAAC from router advertisements, and install rdisc6 so we can
        # trigger one immediately.
        config = {
          boot.kernel.sysctl = {
            "net.ipv6.conf.all.autoconf" = true;
          };
          environment.systemPackages = with pkgs; [
            ndisc6
          ];
        };
      };
    };

    testScript = ''
      start_all()

      with subtest("Wait for CoreRAD and network ready"):
          # Ensure networking is online and CoreRAD is ready.
          router.wait_for_unit("network-online.target")
          client.wait_for_unit("network-online.target")
          router.wait_for_unit("corerad.service")

          # Ensure the client can reach the router.
          client.wait_until_succeeds("ping -c 1 fd00:dead:beef:dead::1")

      with subtest("Verify SLAAC on client"):
          # Trigger a router solicitation and verify a SLAAC address is assigned from
          # the prefix configured on the router.
          client.wait_until_succeeds("rdisc6 -1 -r 10 eth1")
          client.wait_until_succeeds(
              "ip -6 addr show dev eth1 | grep -q 'fd00:dead:beef:dead:'"
          )

          addrs = client.succeed("ip -6 addr show dev eth1")

          assert (
              "fd00:dead:beef:dead:" in addrs
          ), "SLAAC prefix was not found in client addresses after router advertisement"
          assert (
              "/64 scope global temporary" in addrs
          ), "SLAAC temporary address was not configured on client after router advertisement"

      with subtest("Verify HTTP debug server is configured"):
          out = router.succeed("curl -f localhost:9430/metrics")

          assert (
              "corerad_build_info" in out
          ), "Build info metric was not found in Prometheus output"
    '';
  })