#! /bin/sh -e

prog=${0##*/}
fail () { echo >&2 "$prog: $1"; exit 2; }
usage () { echo "usage: $prog [CONF]"; }

bogus=nil
while getopts "h" opt; do
  case $opt in
    h) usage; exit 0 ;;
    *) bogus=t ;;
  esac
done
shift $(( $OPTIND - 1 ))
case $# in 0) op=query ;; 1) op=set conf=$1 ;; *) bogus=t ;; esac
case $bogus in t) usage >&2; exit 2 ;; esac

cd "$HOME/.disorder"
case $op in
  query)
    if ! [ -L passwd ]; then link=bogus
    else link=$(readlink passwd)
    fi
    case $link in
      passwd.*) conf=${link#passwd.} ;;
      *) fail "\`~/.disorder/passwd' not a link to \`passwd.CONF'" ;;
    esac
    echo "$conf"
    ;;
  set)
    if ! [ -f "passwd.$conf" ]; then fail "no config \`passwd.$conf'"; fi
    ln -sf "passwd.$conf" passwd
    ;;
esac