# Tests building and running a GUID Partition Table (GPT) appliance image.
# "Appliance" here means that the image does not contain the normal NixOS
# infrastructure of a system profile and cannot be re-built via
# `nixos-rebuild`.

{ lib, ... }:

let
  rootPartitionLabel = "root";

  imageId = "nixos-appliance";
  imageVersion = "1-rc1";
in
{
  name = "appliance-gpt-image";

  meta.maintainers = with lib.maintainers; [ nikstur ];

  nodes.machine = { config, lib, pkgs, ... }: {

    imports = [ ../modules/image/repart.nix ];

    virtualisation.directBoot.enable = false;
    virtualisation.mountHostNixStore = false;
    virtualisation.useEFIBoot = true;

    # Disable boot loaders because we install one "manually".
    # TODO(raitobezarius): revisit this when #244907 lands
    boot.loader.grub.enable = false;

    system.image.id = imageId;
    system.image.version = imageVersion;

    virtualisation.fileSystems = lib.mkForce {
      "/" = {
        device = "/dev/disk/by-partlabel/${rootPartitionLabel}";
        fsType = "ext4";
      };
    };

    image.repart = {
      name = "appliance-gpt-image";
      # OVMF does not work with the default repart sector size of 4096
      sectorSize = 512;
      partitions = {
        "esp" = {
          contents =
            let
              efiArch = config.nixpkgs.hostPlatform.efiArch;
            in
            {
              "/EFI/BOOT/BOOT${lib.toUpper efiArch}.EFI".source =
                "${pkgs.systemd}/lib/systemd/boot/efi/systemd-boot${efiArch}.efi";

              "/EFI/Linux/${config.system.boot.loader.ukiFile}".source =
                "${config.system.build.uki}/${config.system.boot.loader.ukiFile}";
            };
          repartConfig = {
            Type = "esp";
            Format = "vfat";
            # Minimize = "guess" seems to not work very vell for vfat
            # partitons. It's better to set a sensible default instead. The
            # aarch64 kernel seems to generally be a little bigger than the
            # x86_64 kernel. To stay on the safe side, leave some more slack
            # for every platform other than x86_64.
            SizeMinBytes = if config.nixpkgs.hostPlatform.isx86_64 then "64M" else "96M";
          };
        };
        "root" = {
          storePaths = [ config.system.build.toplevel ];
          repartConfig = {
            Type = "root";
            Format = config.fileSystems."/".fsType;
            Label = rootPartitionLabel;
            Minimize = "guess";
          };
        };
      };
    };
  };

  testScript = { nodes, ... }: ''
    import os
    import subprocess
    import tempfile

    tmp_disk_image = tempfile.NamedTemporaryFile()

    subprocess.run([
      "${nodes.machine.virtualisation.qemu.package}/bin/qemu-img",
      "create",
      "-f",
      "qcow2",
      "-b",
      "${nodes.machine.system.build.image}/${nodes.machine.image.repart.imageFile}",
      "-F",
      "raw",
      tmp_disk_image.name,
    ])

    # Set NIX_DISK_IMAGE so that the qemu script finds the right disk image.
    os.environ['NIX_DISK_IMAGE'] = tmp_disk_image.name

    os_release = machine.succeed("cat /etc/os-release")
    assert 'IMAGE_ID="${imageId}"' in os_release
    assert 'IMAGE_VERSION="${imageVersion}"' in os_release

    bootctl_status = machine.succeed("bootctl status")
    assert "Boot Loader Specification Type #2 (.efi)" in bootctl_status
  '';
}