#!/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

#######################################
# Wrapper for executing commands in the desired chroot environment.
# Globals:
#   TERM
# Arguments:
#   $1: Target of the chroot environment.
#   $@: Commands and options and parameters to be executed in chroot.
#######################################
do_in_target() {
  declare var_chroot_target="$1"; shift
  declare ary_chroot_command=("$@")
  do_log "info" "false" "Executing in the target system '${var_chroot_target}' command: '${ary_chroot_command[*]}'."
  chroot "${var_chroot_target}" /usr/bin/env -i \
    HOME=/root \
    PATH=/usr/sbin:/usr/bin:/sbin:/bin \
    TERM="${TERM}" \
    "${ary_chroot_command[@]}"
}

#######################################
# Wrapper around 'printf' for clean code.
# Globals:
#   C_RES
# Arguments:
#   $1: One of "${C_BLA}" | "${C_RED}" | "${C_GRE}" | "${C_YEL}" | "${C_BLU}" | "${C_MAG}" | "${C_CYA}" | "${C_WHI}"
#   $2: Text string to print on terminal.
#######################################
do_print_color() {
  printf "%s\n" "${1}${2}${C_RES}"
}

#######################################
# Wrapper around 'printf' for clean, uniform terminal output and line fold for long text strings for better readability.
# Globals:
#   C_RES
# Arguments:
#   $1: One of "${C_BLA}" | "${C_RED}" | "${C_GRE}" | "${C_YEL}" | "${C_BLU}" | "${C_MAG}" | "${C_CYA}" | "${C_WHI}"
#   $2: Text string to print on terminal.
#######################################
do_print_fold() {
  declare var_color="$1"; shift
  declare var_msg_string="$*"
  declare var_formatted_String="${var_color}${var_msg_string}${C_RES}"
  printf "%b\n" "${var_formatted_String}" | fold -s -w 76 | sed '1! s/^/    /'
}

#######################################
# Wrapper around 'printf' for logfile redirect.
# Arguments:
#   $1: Text string to redirect to a log file.
#######################################
do_print_log() {
  printf "%s\n" "${1}"
}

#######################################
# Helper Module to generate a Subnet Mask out of an IP in CCDIR Notation.
# Arguments:
#   $1: IPv4 in CCDIR Notation, e.g.,: 192.168.128.128/24
# Returns:
#   0 : In every case a zero return value is delivered.
#######################################
generate_subnetmask() {
  declare var_arg="$1"
  declare var_prefix="${var_arg#*/}"
  declare var_mask_int=""
  declare var_has_ipv4_subnet=""
  var_mask_int=$((0xFFFFFFFF << (32 - var_prefix) & 0xFFFFFFFF))
  var_has_ipv4_subnet=$(printf "%d.%d.%d.%d" \
    $(((var_mask_int >> 24) & 0xFF)) \
    $(((var_mask_int >> 16) & 0xFF)) \
    $(((var_mask_int >> 8) & 0xFF)) \
    $((var_mask_int & 0xFF)))
  echo "${var_has_ipv4_subnet}"
  return 0
}

#######################################
# Converts characters such as spaces, inverted commas, backslashes, and other special
# characters so that they can be safely used as arguments in a shell command.
# Arguments:
#   $1: String to sanitize.
#######################################
sanitize_input() {
  # shellcheck disable=SC2155
  declare var_safe_out=$(printf "%q" "$1")
  echo "${var_safe_out}"
}

#######################################
# Remove any leading or trailing whitespace.
# Arguments:
#   $1: String to clean.
#######################################
remove_whitespace() {
  # shellcheck disable=SC2155
  declare var_out=$(printf "%s" "$1" | xargs)
  echo "${var_out}"
}

#######################################
# Function to escape all shell metacharacters
# Arguments:
#   $1: String to Sanitize
#######################################
sanitize_shell_literal() {
  declare input="$1"
  ### %q quotes the string so that the shell re-reads it as the original literal
  printf '%q' "${input}"
}

#######################################
# Function to remove any character not in the allowed set
# Arguments:
#   $1: String to Sanitize
#######################################
sanitize_string() {
  declare input="$1"
  ### Define allowed characters:
  ### letters, digits, dot, underscore, slash, equals, [, ], colon, double-quote, hyphen, space.
  declare allowed='a-zA-Z0-9._/=\[\]:"\-+ '
  printf '%s' "${input}" | tr -cd "${allowed}"
}

#######################################
# Helper module for full upgrade, autoremove and autoclean.
# Arguments:
#   None
#######################################
update_upgrade() {
  apt-get update -y
  apt-get upgrade -y
  apt-get autoclean -y
  apt-get autopurge -y
  apt-get autoremove -y
}

#######################################
# Wrapper for secure curl.
# Globals:
#   ERR_DOWNLOAD_FAILED
#   ERR_NO_DOWNLOAD_ARG
# Arguments:
#   $1: URL from which to download a specific file.
#   $2: /path/to/file to be saved to.
# Returns:
#   ${ERR_DOWNLOAD_FAILED}: Download failed.
#   ${ERR_NO_DOWNLOAD_ARG}: No arguments specified.
#######################################
scurl() {
  if [[ $# -ne 2 ]]; then
    do_log "error" "false" "Usage: scurl <URL> <path/to/file>"
    return "${ERR_NO_DOWNLOAD_ARG}"
  fi
  declare url="$1"
  declare output_path="$2"
  if ! curl --doh-url "https://dns01.eddns.eu/dns-query" \
            --doh-cert-status \
            --tlsv1.3 \
            -sSf \
            -o "${output_path}" \
            "${url}"
  then
    do_log "error" "false" "Download failed for URL: '${1}'."
    return "${ERR_DOWNLOAD_FAILED}"
  fi
}

#######################################
# Wrapper for secure wget.
# Globals:
#   ERR_DOWNLOAD_FAILED
#   ERR_NO_DOWNLOAD_ARG
# Arguments:
#   $1: URL from which to download a specific file.
#   $2: /path/to/file to be saved to.
# Returns:
#   ${ERR_DOWNLOAD_FAILED}: Download failed.
#   ${ERR_NO_DOWNLOAD_ARG}: No arguments specified.
#######################################
swget() {
  if [[ $# -ne 2 ]]; then
    do_log "error" "false" "Usage: swget <URL> <path/to/file>"
    return "${ERR_NO_DOWNLOAD_ARG}"
  fi
  declare url="$1"
  declare output_path="$2"
  if ! wget --show-progress \
            --no-clobber \
            --https-only \
            --secure-protocol=TLSv1_3 \
            -qO "${output_path}" \
            "${url}"
  then
    do_log "error" "false" "Download failed for URL: '${1}'."
    return "${ERR_DOWNLOAD_FAILED}"
  fi
}
# vim: number et ts=2 sw=2 sts=2 ai tw=128 ft=sh