{ pkgs, makeTest }:

with pkgs.lib;

{
  makeEc2Test =
    {
      name,
      image,
      userData,
      script,
      hostname ? "ec2-instance",
      sshPublicKey ? null,
      meta ? { },
    }:
    let
      metaData = pkgs.stdenv.mkDerivation {
        name = "metadata";
        buildCommand =
          ''
            mkdir -p $out/1.0/meta-data
            ln -s ${pkgs.writeText "userData" userData} $out/1.0/user-data
            echo "${hostname}" > $out/1.0/meta-data/hostname
            echo "(unknown)" > $out/1.0/meta-data/ami-manifest-path
          ''
          + optionalString (sshPublicKey != null) ''
            mkdir -p $out/1.0/meta-data/public-keys/0
            ln -s ${pkgs.writeText "sshPublicKey" sshPublicKey} $out/1.0/meta-data/public-keys/0/openssh-key
          '';
      };
      indentLines = str: concatLines (map (s: "  " + s) (splitString "\n" str));
    in
    makeTest {
      name = "ec2-" + name;
      nodes = { };
      testScript =
        ''
          import os
          import subprocess
          import tempfile

          image_dir = os.path.join(
              os.environ.get("TMPDIR", tempfile.gettempdir()), "tmp", "vm-state-machine"
          )
          os.makedirs(image_dir, mode=0o700, exist_ok=True)
          disk_image = os.path.join(image_dir, "machine.qcow2")
          subprocess.check_call(
              [
                  "qemu-img",
                  "create",
                  "-f",
                  "qcow2",
                  "-F",
                  "qcow2",
                  "-o",
                  "backing_file=${image}",
                  disk_image,
              ]
          )
          subprocess.check_call(["qemu-img", "resize", disk_image, "10G"])

          # Note: we use net=169.0.0.0/8 rather than
          # net=169.254.0.0/16 to prevent dhcpcd from getting horribly
          # confused. (It would get a DHCP lease in the 169.254.*
          # range, which it would then configure and promptly delete
          # again when it deletes link-local addresses.) Ideally we'd
          # turn off the DHCP server, but qemu does not have an option
          # to do that.
          start_command = (
              "qemu-kvm -m 1024"
              + " -device virtio-net-pci,netdev=vlan0"
              + " -netdev 'user,id=vlan0,net=169.0.0.0/8,guestfwd=tcp:169.254.169.254:80-cmd:${pkgs.micro-httpd}/bin/micro_httpd ${metaData}'"
              + f" -drive file={disk_image},if=virtio,werror=report"
              + " $QEMU_OPTS"
          )

          machine = create_machine(start_command)
          try:
        ''
        + indentLines script
        + ''
          finally:
            machine.shutdown()
        '';

      inherit meta;
    };
}
