#!/bin/bash

set -eo pipefail

output_owner_is_root() {
  [ "$output_owner_uid" -eq 0 ]
}

output_owner_user_exists() {
  getent passwd "$output_owner_uid" >/dev/null
}

output_owner_non_root_user_exists() {
  output_owner_user_exists
}

add_docker_user_with_homedir_rwx_by_output_owner() {
  useradd -m docker -u "$output_owner_uid"
  echo 'docker ALL=(ALL) NOPASSWD: ALL' >> /etc/sudoers
}

add_docker_user_with_homedir_that_output_owner_can_compile_in() {
  if output_owner_is_root; then
    echo >&2 "ERROR: output owner can't be root"
    exit 1
  fi

  if output_owner_non_root_user_exists; then
    return
  fi

  add_docker_user_with_homedir_rwx_by_output_owner
}

output_owner_uid="$1"
if [[ $# -ne 1 ]]; then
  echo >&2 "Usage: $(basename "$0") <output_owner_uid>"
  exit 1
fi

add_docker_user_with_homedir_that_output_owner_can_compile_in