#!/usr/bin/env bash

set -euo pipefail
IFS='
'

if [ $# != 2 ]
then
    >&2 echo "Error: expect 2 arguments"
    exit 1
elif [[ $1 == "-e" ]]
then
    user_info=$(getent passwd $2)
    if [[ $user_info == "" ]]
    then
        echo no
    else
        echo yes
    fi
elif [[ $1 == "-i" ]]
then
    getent passwd $2
else
    >&2 echo "Error: unknown flag"
    exit 1
fi