liminix/modules/zyxel-dual-image/service.nix

{
  liminix
, lib
, zyxel-bootconfig
}:
{ ensureActiveImage, primaryMtdPartition, secondaryMtdPartition, bootConfigurationMtdPartition, kernelCommandLineSource }:
let
  inherit (liminix.services) oneshot;
  activeImageIndex = if ensureActiveImage == "primary" then 0 else 1;
in oneshot {
  name = "zyxel-boot-configure";
  up = ''
    set -- $(cat /proc/device-tree/chosen/bootargs)
    for x in "$@"; do
        case "$x" in
            bootImage=*)
            BOOT_IMAGE="''${x#bootImage=}"
            echo "Current boot image is $BOOT_IMAGE."
            ;;
        esac
    done

    if test -z "$BOOT_IMAGE"; then
      echo "No valid image was provided in the kernel command line."
      exit 1
    else
      ${lib.getExe zyxel-bootconfig} ${bootConfigurationMtdPartition} set-image-status "$BOOT_IMAGE" valid
      ${lib.getExe zyxel-bootconfig} ${bootConfigurationMtdPartition} set-active-image ${toString activeImageIndex}

      echo "Active image is now ${ensureActiveImage}"
    fi
  '';
}