#!/bin/bash
# ---------------------------------------------------------------------------
# makeuser - tilde.club new user creation
# Usage: makeuser [-h|--help] <username> <email> "<pubkey>"
# ---------------------------------------------------------------------------

PROGNAME=${0##*/}
VERSION="0.1"

error_exit() {
  echo -e "${PROGNAME}: ${1:-"Unknown Error"}" >&2
  exit 1
}

usage() {
  echo -e "usage: $PROGNAME [-h|--help] <username> <email> \"<pubkey>\""
}

sub_to_list() {
  echo "
From: $1
Subject: subscribe
" | sudo -u $1 sendmail tildeclub-join@lists.tildeverse.org
}

is_banned() {
  while read -r line; do
    banned_user=$(echo "$line" | awk '{print $1}')
    banned_email=$(echo "$line" | awk '{print $2}')
    if [[ "$1" == "$banned_user" || "$2" == "$banned_email" ]]; then
      return 0
    fi
  done < /var/signups_banned
  return 1
}

move_to_current() {
  grep -E "makeuser\s+$1\s+$2\s+\"$3\"" /var/signups >> /var/signups_current
  sed -i "/makeuser\s\+$1\s\+$2\s\+\"$3\"/d" /var/signups
}

case $1 in
  -h | --help)
    usage; exit ;;
  -* | --*)
    usage; error_exit "unknown option $1" ;;
  *)
    [[ $# -ne 3 ]] && error_exit "not enough args"

    if is_banned "$1" "$2"; then
      error_exit "user or email is banned"
    fi

    if id $1 > /dev/null 2>&1; then
        exit 0
    fi

    echo "adding new user $1"
    newpw=$(pwgen -1B 10)
    sudo useradd -m -g 100 -s /usr/bin/bash $1 \
        || error_exit "couldn't add user"
    echo "$1:$newpw" | sudo chpasswd

    echo "sending welcome mail"
    sed -e "s/newusername/$1/g" -e "s/newpassword/$newpw/" /usr/local/bin/welcome-email.tmpl \
        | sendmail $1 $2 root

    echo "subscribing to mailing list"
    sub_to_list $1

    echo "removing .git and README.md from new homedir"
    sudo rm -rf /home/$1/.git
    sudo rm -rf /home/$1/README.md

    # Changing last edit date.
    sudo touch /home/$1/.new_user

    echo "adding ssh pubkey"
    echo "$3" | sudo tee /home/$1/.ssh/authorized_keys

    echo "moving user from signups to signups_current"
    move_to_current $1 $2 "$3"

    echo "announcing new user on mastodon"
    toot "welcome new user ~$1!"

esac
