# Copyright 2024 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
SCRIPT_ROOT=$(dirname $(readlink -f "$0"))
SCRIPT_ROOT=${SCRIPT_ROOT%cos}
. "${SCRIPT_ROOT}/build_library/build_common.sh" || exit 1

# Script must be run inside the chroot.
restart_in_chroot_if_needed "$@"

DEFINE_string kernel_tree "" \
  "In-chroot path to the kernel tree."
DEFINE_string arch "" \
  "Architecture of the config."
DEFINE_string config '' \
  'Name of the config. The config is assumed to be in the arch/${arch}/configs directory.'
DEFINE_string update_chroot '' \
  'Whether or not to update the chroot before running menuconfig. Defaults to true.'

# Parse command line.
FLAGS "$@" || exit 1
eval set -- "${FLAGS_ARGV}"

switch_to_strict_mode

menuconfig() {
  local -r config=$1
  local -r arch=$2

  local tuple
  case "${arch}" in
    x86_64)
      tuple=x86_64-cros-linux-gnu
      ;;
    arm64)
      tuple=aarch64-cros-linux-gnu
      ;;
    *)
      error "Unknown arch ${arch}"
      return 1
      ;;
  esac

  local build_dir
  build_dir="$(mktemp -d)"
  cp "${config}" "${build_dir}/.config"
  make -C "${FLAGS_kernel_tree}" O="${build_dir}" ARCH="${arch}" \
    CC="${tuple}-clang" LD="${tuple}-ld.lld" CROSS_COMPILE="${tuple}-" \
    menuconfig
  cp "${build_dir}/.config" "${config}"
  rm -rf "${build_dir}"
}

main() {
  if [[ -z "${FLAGS_kernel_tree}" ]]; then
    error "Please provide a --kernel_tree value"
    return 1
  fi

  local -r config_path="${FLAGS_kernel_tree}/arch/${FLAGS_arch}/configs/${FLAGS_config}"

  # The arch used for the config path is not necessarily the one expected
  # by the compiler.
  local compiler_arch="${FLAGS_arch}"
  if [[ "${FLAGS_arch}" == "x86" ]]; then
    compiler_arch=x86_64
  fi

  if [[ "${FLAGS_update_chroot}" != "false" ]]; then
    update_chroot
  fi
  menuconfig "${config_path}" "${compiler_arch}"
}

main "$@"