#!/bin/bash
# SPDX-Version: 3.0
# SPDX-CreationInfo: 2025-06-17; WEIDNER, Marc S.; <msw@coresecret.dev>
# SPDX-ExternalRef: GIT https://git.coresecret.dev/msw/CISS.debian.installer.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.installer
# SPDX-Security-Contact: security@coresecret.eu

#######################################
# Header, Footer wrapper for dynamically output.
# Globals:
#   none
# Arguments:
#   1: Text.
#   2: Width of Terminal.
#######################################
center() {
  declare var_text="$1"
  declare var_width="$2"
  declare var_padding=$(( (var_width - ${#var_text}) / 2 ))
  printf "%*s%s%*s\n" "${var_padding}" "" "${var_text}" "${var_padding}" ""
}

#######################################
# Usage Wrapper 'CISS.debian.installer'.
# Globals:
#   none
# Arguments:
#   0: Script Name
#######################################
usage() {
  # shellcheck disable=SC2155
  declare var_cols=$(tput cols 2> /dev/null || echo 80)

  # shellcheck disable=SC2155
  declare var_header=$(center "V8.00.000.2025.06.17                                          CISS.debian.installer" "${var_cols}")
  # shellcheck disable=SC2155
  declare var_footer=$(center "V8.00.000.2025.06.17                                          CISS.debian.installer" "${var_cols}")

  {
    echo -e "\e[97m${var_header} \e[0m"
    echo
    echo -e "\e[92mCISS.debian.installer from https://git.coresecret.dev/msw \e[0m"
    echo -e "\e[92m${VAR_VERSION} \e[0m"
    echo -e "\e[92mA powerful Debian installer for setting up a hardened Debian environment. \e[0m"
    echo
    echo -e "\e[97m(c) Marc S. Weidner, 2018 - 2025 \e[0m"
    echo -e "\e[97m(p) Centurion Press, 2024 - 2025 \e[0m"
    echo
    echo -e "\e[91mUse only in trusted, non-production environments unless code audited! \e[0m"
    echo
    echo -e "\e[97m${0} <option>, where <option> is one or more of: \e[0m"
    echo
    echo -e "\e[97m  --help, -h \e[0m"
    echo "    What you're looking at."
    echo
    echo -e "\e[97m  --autoinstall, -a \e[0m"
    echo -e "\e[93m    All data on the disks specified in './.preseed/partitioning.yaml' will be destroyed! \e[0m"
    echo "    Headless mode. Skip the dialog wrapper, provider note screen and interactive kernel selector dialog."
    echo "    No user interaction is required in autoinstall mode."
    echo
    echo -e "\e[97m  --contact, -c \e[0m"
    echo "    Show author contact information."
    echo
    echo -e "\e[97m  --debug, -d <MODE> \e[0m"
    echo "    Whereas <MODE> can be one or both of the following: 'TRAP' or 'XTRACE'."
    echo "    - XTRACE uses the 'set -x' capability to trace every command executed."
    echo "    - TRAP uses the bash 'trap DEBUG' capability."
    echo -e "\e[93m    Detailed debugging information is written to: \e[0m"
    echo "    - /tmp/.ciss/log/ciss_debian_installer_$$_debug.log"
    echo "    - /tmp/.ciss/log/ciss_debian_installer_$$_trace.log"
    echo "    - /tmp/.ciss/log/ciss_debian_installer_$$_var.log"
    echo
    echo -e "\e[97m  --log, -l <LEVEL> \e[0m"
    echo "    This changes the default log level from 'info' to one of the following values:"
    echo "      debug"
    echo "      info"
    echo "      notice"
    echo "      warn"
    echo "      error"
    echo "      critical"
    echo "      fatal"
    echo "      emergency"
    echo "    Defaults to 'info'."
    echo -e "\e[93m    The Installation log is written to: \e[0m"
    echo "    - /tmp/.ciss/log/ciss_debian_installer_$$_install.log"
    echo -e "\e[93m    The Error log is written to: \e[0m"
    echo "    - /tmp/.ciss/log/ciss_debian_installer_$$_error.log"
    echo
    echo -e "\e[97m  --renice-priority <PRIORITY> \e[0m"
    echo "    Reset the nice priority value of the script and all its children"
    echo "    to the desired <PRIORITY>. MUST be an integer (between '-19' and 19)."
    echo "    Negative (higher) values MUST be enclosed in double quotes '\"'."
    echo "    Defaults to '0'."
    echo
    echo -e "\e[97m  --reionice-priority <CLASS> <PRIORITY> \e[0m"
    echo "    Reset the ionice priority value of the script and all its children"
    echo "    to the desired <CLASS>. MUST be an integer:"
    echo "      1: realtime"
    echo "      2: best-effort"
    echo "      3: idle"
    echo "    Defaults to '2'."
    echo "    Whereas <PRIORITY> MUST be an integer as well between:"
    echo "      0: highest priority and"
    echo "      7: lowest priority."
    echo "    Defaults to '4'."
    echo "    A real-time I/O process can significantly slow down other processes"
    echo "    or even cause them to starve if it continuously requests I/O."
    echo
    echo -e "\e[97m  --version, -v \e[0m"
    echo "    Show version of ${0}."
    echo
    echo -e "\e[93m💡 Notes:\e[0m"
    echo -e "\e[97m🔵 You MUST be 'root' to run this script. \e[0m"
    echo -e "\e[97m🔵 You MUST edit './.preseed/preseed.yaml' in advance. \e[0m"
    echo -e "\e[97m🔵 You MUST edit './.preseed/partitioning.yaml' in advance. \e[0m"
    echo -e "\e[97m🔵 You MUST edit './.preseed/password_grub.txt' in advance. \e[0m"
    echo -e "\e[97m🔵 You MUST edit './.preseed/password_luks_boot.txt' in advance. \e[0m"
    echo -e "\e[97m🔵 You MUST edit './.preseed/password_luks_common.txt' in advance. \e[0m"
    echo -e "\e[97m🔵 You MUST edit './.preseed/password_luks_nuke.txt' in advance. \e[0m"
    echo -e "\e[97m🔵 You SHOULD use the provided YAML-Configuration-File Editor. \e[0m"
    echo
    echo -e "\e[95m💷 Please consider donating to my work at: \e[0m"
    echo -e "\e[95m🌐 https://coresecret.eu/spenden/ \e[0m"
    echo
    echo -e "\e[97m${var_footer} \e[0m"
  } | less -R
}
# vim: number et ts=2 sw=2 sts=2 ai tw=128 ft=sh