#!/usr/bin/env bash
#
# Copyright 2013 Victor Penso
#
# 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, see <http://www.gnu.org/licenses/>.
#

VERSION=0.1


SCRIPT=${0##*/}

_error() {
  echo 1>&2 "Error: $@"
  echo "See \`$SCRIPT help\` for usage."
  exit 1
}

HELP=\
"Usage: $SCRIPT command [arguments]

The \`$SCRIPT\` script is a wrapper for \`sshuttle\`, and
enables access to remote networks over SSH. 

Commands:

  co|connect [user@]host[:port] [range] 
    Hook into a remote network.

  st|status
    Show Shuttle PID if running.  

  di|disconnect
    Close connection to remote network.

Environment:

  SSHUTTLE_PID_FILE 
    Stores the process ID of the shuttle daemon.
    Default \`/tmp/sshuttle.pid\`."

SSHUTTLE_PID_FILE=${SSHUTTLE_PID_FILE:-/tmp/sshuttle.pid}

connect() {
  remote=$1
  range=${2:-'0/0'}
  sshuttle --remote $remote --dns --daemon --pidfile=$SSHUTTLE_PID_FILE $range
}

_status() {
  if [ -e $SSHUTTLE_PID_FILE ] ; then
    ps $(cat $SSHUTTLE_PID_FILE) >/dev/null
    if [[ $? -eq 0 ]] ; then
      echo "Sshuttle running with PID $(cat $SSHUTTLE_PID_FILE)."
      exit 0
    fi
  fi
  echo "Sshuttle not connected." 
}

disconnect() {
  test -e $SSHUTTLE_PID_FILE || _error "Shuttle PID file missing $SSHUTTLE_PID_FILE!" 
  kill -TERM $(cat $SSHUTTLE_PID_FILE)
}

# Read the command-line arguments
_command=$1 ; shift
case "$_command" in
  "co"|"connect") connect "$@" ;;
  "st"|"status") _status ;; 
  "di"|"disconnect") disconnect ;;
  *) echo "$HELP" ;;
esac

exit 0