#!/bin/sh

# shellcheck source=../lib/load-configuration
. "${0%/*}/../lib/load-configuration"

# shellcheck disable=SC2016
usage() {
  >&2 echo 'usage:'
  >&2 echo '  create-build-support-package [options] --from $pkgname-$epoch:$pkgver-$pkgrel.$sub_pkgrel [--] $file1 $file2 $file3 ...'
  >&2 echo '    create $pkgname-shim containing'
  >&2 echo '    $file1, $file2, ... from the original package'
  >&2 echo '  create-build-support-package [options] --shim $pkgfile'
  >&2 echo '    insert $pkgfile into $repo_arch/build-support/$pkgname-shim'
  >&2 echo ''
  >&2 echo 'possible options:'
  >&2 echo '  -a|--arch $repo_arch: (required)'
  >&2 echo '    Operate on repository of given architecture.'
  >&2 echo '  -h|--help:'
  >&2 echo '    Show this help and exit.'
  >&2 echo '  -w|--wait:'
  >&2 echo '    Wait for lock if necessary.'
  [ -z "$1" ] && exit 1 || exit "$1"
}

eval set -- "$(
  getopt -o a:hw \
    --long arch \
    --long from \
    --long help \
    --long shim \
    --long wait \
    -n "$(basename "$0")" -- "$@" || \
    echo usage
  )"

repo_arch=''
shim_package=''
source_package=''
wait_for_lock='-n'
while true; do
  case "$1" in
    -a|--arch)
      if [ -n "${repo_arch}" ]; then
        >&2 prinf -- '-a|--arch given more than once.\n'
        usage
      fi
      shift
      repo_arch="$1"
    ;;
    --from)
      if [ -n "${source_package}" ]; then
        >&2 prinf -- '--from given more than once.\n'
        usage
      fi
      shift
      source_package="$1"
    ;;
    -h|--help)
      usage 0
    ;;
    --shim)
      if [ -n "${shim_package}" ]; then
        >&2 prinf -- '--shim given more than once.\n'
        usage
      fi
      shift
      shim_package="$1"
    ;;
    -w|--wait)
      wait_for_lock=''
    ;;
    --)
      shift
      break
    ;;
    *)
      >&2 printf 'Whoops, forgot to implement option "%s" internally.\n' \
        "$1"
      exit 42
    ;;
  esac
done

if [ -n "${source_package}" ] \
  && [ -n "${shim_package}" ]; then
  >&2 echo 'Conflicting parameters: --from and --shim'
  usage
fi

exec 9> "${sanity_check_lock_file}"
verbose_flock -s ${wait_for_lock} 9

tmp_dir=$(mktemp -d 'tmp.create-build-support.XXXXXXXXXX')
# shellcheck disable=SC2064
trap "rm -rf --one-file-system '${tmp_dir:?}'" EXIT

if [ -n "${source_package}" ]; then
  # create shim_package from source_package

  if [ $# -eq 0 ]; then
    usage 1
  fi

  pkg=$(
    # shellcheck disable=SC2016
    {
      printf 'SELECT DISTINCT '
      mysql_package_name_query
      printf ' FROM `binary_packages`'
      mysql_join_binary_packages_binary_packages_in_repositories
      mysql_join_binary_packages_in_repositories_repositories
      mysql_join_repositories_architectures
      printf ' WHERE `repositories`.`is_on_master_mirror`'
      printf ' AND `architectures`.`name`=from_base64("%s")' \
        "$(
          printf '%s' "${repo_arch}" \
            | base64 -w0
        )"
      printf ' AND '
      mysql_package_name_query '' 'XX' \
        | sed '
          s/,"-",`XX.*\.pkg\.tar\.xz"//
        '
      printf '=from_base64("%s")' \
        "$(
          printf '%s' "${source_package}" \
            | base64 -w0
        )"
    } \
      | mysql_run_query \
      | tr '\t' ' '
  )

  if [ -z "${pkg}" ]; then
    >&2 printf 'Could not find %s/%s in the database.\n' \
      "${repo_arch}" "${source_package}"
    exit 1
  fi

  if printf '%s\n' "${pkg}" \
    | wc -l \
    | grep -vqxF '1'; then
    >&2 printf 'Package %s/%s was found multiple times:\n' \
      "${repo_arch}" "${source_package}"
    >&2 printf '%s\n' "${pkg}"
    exit 1
  fi

  new_pkg="${pkg%-*-*-*}"
  new_pkg="${new_pkg}-shim${pkg#${new_pkg}}"

  failsafe_rsync \
    "${master_mirror_rsync_directory}/pool/${pkg}" \
    "${tmp_dir}/"

  mkdir "${tmp_dir}/content"
  bsdtar -C "${tmp_dir}/content" -xf "${tmp_dir}/${pkg}" \
    '.BUILDINFO' \
    '.PKGINFO' \
    "$@"

  # TODO: mangle customizable meta-infos here (new provides, keep some
  # depends)
  sed -i '
    /^pkgname = / s/ \S\+$/\0-shim\nprovides =\0/
    /^depend = /d
  ' "${tmp_dir}/content/.PKGINFO"

  # from /usr/bin/makepkg
  list_package_files() {
    (
      cd "${tmp_dir}/content"
      find . -path './.*' \! -name '.'; find . \! -path './.*' \! -name '.' \
        | LC_ALL=C sort
    ) \
      | sed -e 's|^\./||' \
      | tr '\n' '\0'
  }

  list_package_files \
    | LANG=C bsdtar -C "${tmp_dir}/content" -cnf - --format=mtree \
      --options='!all,use-set,type,uid,gid,mode,time,size,md5,sha256,link' \
      --null --files-from - --exclude .MTREE \
    | gzip -c -f -n \
    > "${tmp_dir}/content/.MTREE"

  list_package_files \
    | LANG=C bsdtar -C "${tmp_dir}/content" -cnf - --null --files-from - \
    | xz -c -z - \
    > "${tmp_dir}/${new_pkg}"

  rm -rf --one-file-system "${tmp_dir:?}/content"
  mv "${tmp_dir}/${new_pkg}" "${work_dir}/"
  >&2 printf 'Please sign %s with a build slave key and run\n' \
    "${work_dir}/${new_pkg}"
  # shellcheck disable=SC2016
  >&2 printf 'create-build-support-package --shim $pkgfile\n'

elif [ -n "${shim_package}" ]; then
  # insert shim_package into [build-support]

  exec 8> "${package_database_lock_file}"
  verbose_flock ${wait_for_lock} 8

  # TODO: find original package in database, check signature, retrieve
  # db, insert package into db, copy row in `binary_packages`, insert
  # row into `binary_packages_in_repositories`, add package to pool/,
  # send db

else
  >&2 echo 'Need either --from or --shim.'
  usage
fi