#!/bin/bash
# SPDX-Version: 3.0
# SPDX-CreationInfo: 2025-05-05; WEIDNER, Marc S.; <msw@coresecret.dev>
# SPDX-ExternalRef: GIT https://git.coresecret.dev/msw/CISS.debian.live.builder.git
# SPDX-FileContributor: WEIDNER, Marc S.; Centurion Intelligence Consulting Agency
# SPDX-FileCopyrightText: 2024-2025; WEIDNER, Marc S.; <msw@coresecret.dev>
# SPDX-FileType: SOURCE
# SPDX-License-Identifier: EUPL-1.2 OR LicenseRef-CCLA-1.0
# SPDX-LicenseComment: This file is part of the CISS.debian.installer.secure framework.
# SPDX-PackageName: CISS.debian.live.builder
# SPDX-Security-Contact: security@coresecret.eu

guard_sourcing

#######################################
# Unbound variable check and call trap on 'ERR'.
# Globals:
#   ERR_UNBOUNDVAR
# Arguments:
#   1: VAR_NAME to check
# Returns:
#   0: on success
#   ERR_UNBOUNDVAR: on failure
#######################################
check_var() {
  declare var_name_to_check="$1"

  if [[ -n "${!var_name_to_check+exists}" ]]; then

    if [[ -n "${!var_name_to_check}" ]]; then

      printf "\e[92m✅ Variable: '%s' exists and is NOT empty: '%s' \e[0m\n" "${var_name_to_check}" "${!var_name_to_check}"

    else

      printf "\e[92m✅ Variable: '%s' exists but is empty. \e[0m\n" "${var_name_to_check}"

    fi

  else

    printf "\e[91m❌ Variable: '%s' is not declared. Exiting Script. \e[0m\n" "${var_name_to_check}" >&2

    return "${ERR_UNBOUNDVAR}"

  fi

  return 0
}
### Prevents accidental 'unset -f'.
# shellcheck disable=SC2034
readonly -f check_var
# vim: number et ts=2 sw=2 sts=2 ai tw=128 ft=sh