bin/tgenv

#!/usr/bin/env bash
set -e
if [ -n "${TGENV_DEBUG}" ]; then
  export PS4='+ [${BASH_SOURCE##*/}:${LINENO}] '
  set -x
fi

# http://stackoverflow.com/questions/1055671/how-can-i-get-the-behavior-of-gnus-readlink-f-on-a-mac
readlink_f() {
  local target_file="${1}"
  local file_name

  while [ "${target_file}" != "" ]; do
    cd "$(dirname ${target_file})"
    file_name="$(basename "${target_file}")"
    target_file="$(readlink "${file_name}")"
  done

  echo "$(pwd -P)/${file_name}"
}

if [ -z "${TGENV_ROOT}" ]; then
  TGENV_ROOT="$(cd "$(dirname "$(readlink_f "${0}")")/.." && pwd)"
else
  TGENV_ROOT="${TGENV_ROOT%/}"
fi
export TGENV_ROOT
PATH="${TGENV_ROOT}/libexec:${PATH}"
export PATH
export TGENV_DIR="${PWD}"

abort() {
  { if [ "${#}" -eq 0 ]; then cat -
    else echo "tgenv: ${*}"
    fi
  } >&2
  exit 1
}

command="${1}"
case "${command}" in
"" )
  { tgenv---version
    tgenv-help
  } | abort
  ;;
-v | --version )
  exec tgenv---version
  ;;
-h | --help )
  exec tgenv-help
  ;;
* )
  command_path="$(command -v "tgenv-${command}" || true)"
  if [ -z "${command_path}" ];then
    { echo "no such command '${command}'"
      tgenv-help
    } | abort
  fi
  shift 1
  exec "${command_path}" "${@}"
  ;;
esac