# In contrast to systemd-networkd-dhcpserver, this test configures
# the router with a static DHCP lease for the client's MAC address.
import ./make-test-python.nix (
  { lib, ... }:
  {
    name = "systemd-networkd-dhcpserver-static-leases";
    meta = with lib.maintainers; {
      maintainers = [ veehaitch ];
    };
    nodes = {
      router = {
        virtualisation.vlans = [ 1 ];
        systemd.services.systemd-networkd.environment.SYSTEMD_LOG_LEVEL = "debug";
        networking = {
          useNetworkd = true;
          useDHCP = false;
          firewall.enable = false;
        };
        systemd.network = {
          networks = {
            # systemd-networkd will load the first network unit file
            # that matches, ordered lexiographically by filename.
            # /etc/systemd/network/{40-eth1,99-main}.network already
            # exists. This network unit must be loaded for the test,
            # however, hence why this network is named such.
            "01-eth1" = {
              name = "eth1";
              networkConfig = {
                DHCPServer = true;
                Address = "10.0.0.1/24";
              };
              dhcpServerStaticLeases = [
                {
                  MACAddress = "02:de:ad:be:ef:01";
                  Address = "10.0.0.10";
                }
              ];
            };
          };
        };
      };

      client = {
        virtualisation.vlans = [ 1 ];
        systemd.services.systemd-networkd.environment.SYSTEMD_LOG_LEVEL = "debug";
        systemd.network = {
          enable = true;
          links."10-eth1" = {
            matchConfig.OriginalName = "eth1";
            linkConfig.MACAddress = "02:de:ad:be:ef:01";
          };
          networks."40-eth1" = {
            matchConfig.Name = "eth1";
            networkConfig = {
              DHCP = "ipv4";
              IPv6AcceptRA = false;
            };
            # This setting is important to have the router assign the
            # configured lease based on the client's MAC address. Also see:
            # https://github.com/systemd/systemd/issues/21368#issuecomment-982193546
            dhcpV4Config.ClientIdentifier = "mac";
            linkConfig.RequiredForOnline = "routable";
          };
        };
        networking = {
          useDHCP = false;
          firewall.enable = false;
          interfaces.eth1 = lib.mkForce { };
        };
      };
    };
    testScript = ''
      start_all()

      with subtest("check router network configuration"):
        router.wait_for_unit("systemd-networkd-wait-online.service")
        eth1_status = router.succeed("networkctl status eth1")
        assert "Network File: /etc/systemd/network/01-eth1.network" in eth1_status, \
          "The router interface eth1 is not using the expected network file"
        assert "10.0.0.1" in eth1_status, "Did not find expected router IPv4"

      with subtest("check client network configuration"):
        client.wait_for_unit("systemd-networkd-wait-online.service")
        eth1_status = client.succeed("networkctl status eth1")
        assert "Network File: /etc/systemd/network/40-eth1.network" in eth1_status, \
          "The client interface eth1 is not using the expected network file"
        assert "10.0.0.10" in eth1_status, "Did not find expected client IPv4"

      with subtest("router and client can reach each other"):
        client.wait_until_succeeds("ping -c 5 10.0.0.1")
        router.wait_until_succeeds("ping -c 5 10.0.0.10")
    '';
  }
)