common.sh

# shellcheck shell=bash
[[ "$DEBUG" ]] && set -x
# https://devhints.io/bash
set -euo pipefail # strict
IFS=$'\n\t'

traperr() {
  echo "ERROR: ${BASH_SOURCE[1]} at about ${BASH_LINENO[0]}"
}

case $(readlink /proc/$$/exe) in
/bin/bash)
  set -o errtrace
  trap traperr ERR
  ;;
esac

function assertDir() {
  local dir="${1:?'Please specify a directory!'}"
  if [ ! -d "$dir" ]; then
    echo "$dir not found"
    exit 2 # ENOENT No such file or directory
  fi
}

function assertFile() {
  local file="${1:?'Please specify a file!'}"
  if [ ! -s "$file" ]; then
    echo "$file not found"
    exit 2 # ENOENT No such file or directory
  fi
}

function printFunction() {
  local padlimit='80'
  local text="$*"
  local pad
  # shellcheck disable=SC2183
  pad="$(printf '%*s' "$padlimit")"
  pad="${pad// /-}"
  printf '%s' "$text "
  printf '%*.*s\n' 0 $((padlimit - "${#text}")) "$pad"
}

# may exceed printFunction's width by 25%
# uses more visually distinctive padding char
function printHeading() {
  local padlimit='100'
  local text="$*"
  local pad
  # shellcheck disable=SC2183
  pad="$(printf '%*s' "$padlimit")"
  pad="${pad// /=}"
  printf '%s' "$text "
  printf '%*.*s\n' 0 $((padlimit - "${#text}")) "$pad"
}

# shellcheck disable=SC2068
function runCMD() {
  echo 'λ' $@
  $@
}

function mkpw() {
  LC_ALL=C tr -dc '[:graph:]' </dev/urandom | head -c "${1:-24}"
}

function prepareSSH() {
  printFunction 'preparing ssh'
  local privateKeyData="${1:-"${SSH_KEY:?'Need private key!'}"}"
  local privateKeyName="${2:-id_ed25519}"
  mkdir -p ~/.ssh
  echo "$privateKeyData" >~/.ssh/"$privateKeyName"
  chmod 0400 ~/.ssh/"$privateKeyName"
}

function prepareGIT() {
  printFunction 'preparing git'
  local repo_path="${1:?'Please specify a git repository!'}"
  local git_mail="${2:-"${MAILBOX:?'Please specify your mail address!'}"}"
  local git_name="${3:-"${GITNAME:?'Please specify your user name!'}"}"
  cd "$repo_path" || (echo "$repo_path does not exist" && exit 2) # ENOENT
  git config --global --add safe.directory "$(pwd)"
  runCMD git config --global user.email "$git_mail"
  runCMD git config --global user.name "$git_name"
}

function prepareGPG() {
  printFunction "preparing gnupg and it's trustdb"
  local gpg_pair="${1:?'Please specify a gpg key pair!'}"
  echo "$gpg_pair" | gpg --import
  gpg --list-keys --with-colons | awk -F: '/fpr:/ {print $10":6:"}' | gpg --import-ownertrust
  gpg --check-trustdb
}

function commitSigned() {
  printFunction 'committing changes'
  local message="${1:?'Please specify a commit message!'}"
  runCMD git add .
  runCMD git commit --gpg-sign -m "$message"
}

function initBranch() {
  printFunction 'initializing ophaned git branch with secret.gpg'
  local branchName="${1:?'Please specify a branch name!'}"
  local recipient="${2:?'Please specify a recipient!'}"
  runCMD git switch --discard-changes --orphan "$branchName"
  runCMD git rm --cached -r . || true
  runCMD git clean -df .??* . || true
  mkpw 32 | gpg --encrypt --sign --armor --recipient "$recipient" | tee secret.gpg || true
  commitSigned "init"
}

function tracerouteSSH() {
  printFunction 'tracing route to ssh port of nodes'
  local sourceFile="${1:?'Please specify a source file!'}"
  local portNumber="${2:-22}"
  local searchPatt='(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)'
  mkfifo addresses
  grep -E -o "$searchPatt" "$sourceFile" >addresses &
  while IFS= read -r ipv4; do
    runCMD mtr --report-wide --no-dns --tcp --port "$portNumber" "$ipv4"
  done <addresses
  rm addresses
}