#!/bin/sh
# Copyright 2022 Simon McVittie
# SPDX-License-Identifier: GPL-2.0-or-later

# create-normal-user [USERNAME]
# Create an ordinary, unprivileged user.

set -eu

usage () {
    echo "Usage: create-normal-user [USERNAME]" >&2
    exit 2
}

create () {
    # shellcheck disable=SC3043
    local user="$1"
    shift

    if command -v adduser >/dev/null; then
        adduser \
            --disabled-login \
            --gecos 'Temporary autopkgtest user,,,' \
            "$user" 2>&1
    elif command -v useradd >/dev/null; then
        useradd \
            --comment 'Temporary autopkgtest user' \
            --create-home \
            --expiredate '' \
            --user-group \
            "$user" 2>&1
    else
        echo "Neither adduser nor useradd is installed" >&2
        return 1
    fi

    echo "$user" > /run/autopkgtest-normal-user
}

case "${1-}" in
    (--)
        shift
        ;;

    (-*)
        usage
        ;;
esac

if [ "$#" -gt 1 ]; then
    usage
fi

if [ "$#" -eq 1 ]; then
    create "$1"
    exit 0
fi

tries=20

for i in $(seq 0 "$tries"); do
    if [ "$i" = 0 ]; then
        user="test"
    else
        random=$(mktemp /tmp/test-XXXXXX)
        user="$(basename "$random")"
        rm -f "$random"
    fi

    if getent passwd "$user" >/dev/null; then
        echo "create-normal-user: '$user' already exists"
    else
        create "$user"
        exit 0
    fi
done

echo "create-normal-user: Unable to generate a new username (tried $tries times)" >&2
exit 1
