#!/bin/bash
# Copyright (C) 2016-2017 Miquel Sabaté Solà <mikisabate@gmail.com>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

set -e

# Show the help message.
__vpnsetup_help() {
    echo -e "vpnsetup [command] [endpoint]\n\nThe vpnsetup commands are:\n"
    tab=$'\t'
    column -t -s $'\t' <<HERE
   start${tab}Start the VPN service.
   restart${tab}Restart the VPN service. The default if no command was passed.
   stop${tab}Stop the VPN service.
HERE

    cat <<EOF

The endpoint is supposed to match a systemd service named 'openvpn@<endpoint>.service'.
Note that this command will effectively modify your /etc/resolv.conf file, and
it expects the following files to be available:

  - /etc/resolv.conf.vpn: file containing your DNS records.
  - /etc/resolv.conf.original: your original /etc/resolv.conf file.
EOF
}

# Check for the required files.

if [ ! -f /etc/resolv.conf.vpn ]; then
    echo -e "You have to create the /etc/resolv.conf.vpn file!\n"
    __vpnsetup_help
    exit 1
fi

if [ ! -f /etc/resolv.conf.original ]; then
    echo -e "You have to create the /etc/resolv.conf.original file!\n"
    __vpnsetup_help
    exit 1
fi

# Parse the given command, taking "restart" as the default.

cmd="restart"
if [ "$1" != "" ]; then
    cmd="$1"
fi

case "$cmd" in
    -h | --help)
        __vpnsetup_help
        exit 0
        ;;
    start | restart)
        sudo cp /etc/resolv.conf.vpn /etc/resolv.conf
        ;;
    stop)
        sudo cp /etc/resolv.conf.original /etc/resolv.conf
        ;;
    *)
        echo "Unknown command $cmd"
        __vpnsetup_help
        exit 1
        ;;
esac

# Check the endpoint to use.
endpoint="SUSE-NUE"
if [ "$2" != "" ]; then
    endpoint="$2"
fi

sudo systemctl $cmd "openvpn@$endpoint.service"