#!/bin/bash
#
# .---.                  .              .
# |                      |              |
# |--- .--. .-.  .-.  .-.|  .-. .--.--. |.-.  .-. .--.  .-.
# |    |   (.-' (.-' (   | (   )|  |  | |   )(   )|  | (.-'
# '    '     --'  --'  -' -  -' '  '   -' -'   -' '   -  --'
#
#                    Freedom in the Cloud
#
# Creates an inventory of remote backup locations
#
# License
# =======
#
# Copyright (C) 2015-2016 Bob Mottram <bob@robotics.uk.to>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero 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 Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

NO_OF_ARGS=$#

PROJECT_NAME='freedombone'

export TEXTDOMAIN=${PROJECT_NAME}-remote
export TEXTDOMAINDIR="/usr/share/locale"

# User to create the list for
MY_USERNAME=$USER

# Filename of the remote backups list
FRIENDS_SERVERS_LIST=

# Minimum password length in characters
MINIMUM_PASSWORD_LENGTH=8

# How many remote locations were specified
entering_remote_backups_ctr=0

# Title shown
TITLE='Remote Backup'

# Whether to include the capability of adding reciprocal user accounts
# such that whoever is running a remote server can also use your server to
# store backups
RECIPROCAL="no"

function show_help {
  echo ''
  echo $"${PROJECT_NAME}-remote -u [username] -l [backup list filename] -m [min password length]"
  echo ''
  echo $'Creates an inventory of remote backup locations'
  echo ''
  echo ''
  echo $'  -h --help             Show help'
  echo $'  -u --username         User to create the backups.list file for'
  echo $'  -l --list             Remote backup list (usually /home/$USER/backup.list)'
  echo $'  -m --min              Minimum password length (characters)'
  echo $'  -r --reciprocal       Whether to add reciprocal user accounts'
  echo $'  -t --title            Title shown'
  echo ''
  exit 0
}

# Get the commandline options
while [[ $# > 1 ]]
do
key="$1"

case $key in
    -h|--help)
    show_help
    ;;
    # backup list filename
    # typically /home/$USER/backup.list
    -l|--list)
    shift
    FRIENDS_SERVERS_LIST="$1"
    ;;
    # username within /home
    -u|--user)
    shift
    MY_USERNAME="$1"
    ;;
    # Minimum password length
    -m|--min)
    shift
    MINIMUM_PASSWORD_LENGTH="$1"
    ;;
    # Title shown
    -t|--title)
    shift
    TITLE="$1"
    ;;
    # reciprocal user accounts
    -r|--reciprocal)
    shift
    RECIPROCAL="yes"
    ;;
    *)
    # unknown option
    ;;
esac
shift
done

function interactive_configuration_remote_backups {
  if [ ! $MY_USERNAME ]; then
      echo $'Please specify a username with the -u option'
      exit 7356
  fi

  if [ ! /home/$MY_USERNAME ]; then
      echo $"The user /home/$MY_USERNAME does not exist on the system"
      exit 3689
  fi

  if [ ! $FRIENDS_SERVERS_LIST ]; then
      FRIENDS_SERVERS_LIST=/home/$MY_USERNAME/backup.list
  fi

  # clear any existing list
  if [ -f $FRIENDS_SERVERS_LIST ]; then
      rm -f $FRIENDS_SERVERS_LIST
      touch $FRIENDS_SERVERS_LIST
  fi
  # number of entries made
  entering_remote_backups_ctr=1

  entering_remote_backups_done="no"
  remote_ssh_username=""
  remote_ssh_domain=""
  remote_ssh_port=""
  remote_ssh_password=""
  remote_ssh_reciprocal_username=""
  remote_ssh_reciprocal_password=""
  while [[ $entering_remote_backups_done == "no" ]]
  do
      data=$(tempfile 2>/dev/null)
      trap "rm -f $data" 0 1 2 5 15
      if [[ $RECIPROCAL == "yes" ]]; then
          dialog --backtitle "Freedombone Configuration" \
              --title "$TITLE ${entering_remote_backups_ctr}" \
              --form "\nPlease specify the SSH login details for the remote server\n\nThe reciprocal entries are optional, and can be used if you wish to set up a user account on this system for whoever runs the remote server to also use for backups" 20 50 8 \
              "Username:" 1 1 "$remote_ssh_username" 1 23 16 15 \
              "Domain:" 2 1 "$remote_ssh_domain" 2 23 16 15 \
              "SSH port:" 3 1 "2222" 3 23 5 4 \
              "Password:" 4 1 "$remote_ssh_password" 4 23 20 100 \
              "Reciprocal Username:" 5 1 "$remote_ssh_reciprocal_username" 5 23 20 100 \
              "Reciprocal Password:" 6 1 "$remote_ssh_reciprocal_password" 6 23 20 100 \
              2> $data
      else
          dialog --backtitle "Freedombone Configuration" \
              --title "$TITLE ${entering_remote_backups_ctr}" \
              --form "\nPlease specify the SSH login details for the remote server" 15 50 4 \
              "Username:" 1 1 "$remote_ssh_username" 1 23 16 15 \
              "Domain:" 2 1 "$remote_ssh_domain" 2 23 16 15 \
              "SSH port:" 3 1 "2222" 3 23 5 4 \
              "Password:" 4 1 "$remote_ssh_password" 4 23 20 100 \
              2> $data
      fi
      sel=$?
      case $sel in
          1) entering_remote_backups_done="yes";;
          255) entering_remote_backups_done="yes";;
      esac
      remote_ssh_username=$(cat $data | sed -n 1p)
      remote_ssh_domain=$(cat $data | sed -n 2p)
      remote_ssh_port=$(cat $data | sed -n 3p)
      remote_ssh_password=$(cat $data | sed -n 4p)
      remote_ssh_reciprocal_username=$(cat $data | sed -n 5p)
      remote_ssh_reciprocal_password=$(cat $data | sed -n 6p)
      if [[ $remote_ssh_username != "" && \
          $remote_ssh_domain != "" && \
          $remote_ssh_port != "" && \
          $remote_ssh_password != "" ]]; then

          if [ ${#remote_ssh_password} -lt $MINIMUM_PASSWORD_LENGTH ]; then
              dialog --title "Password quality check" --msgbox "The password given was too short. It must be at least $MINIMUM_PASSWORD_LENGTH characters" 6 40
          else

              if [[ $RECIPROCAL == "yes" ]]; then
                  if [[ $remote_ssh_reciprocal_username != "" && \
                        $remote_ssh_reciprocal_password != "" ]]; then
                      if [ ${#remote_ssh_reciprocal_password} -lt $MINIMUM_PASSWORD_LENGTH ]; then
                          dialog --title "Password quality check" --msgbox "The reciprocal password given was too short. It must be at least $MINIMUM_PASSWORD_LENGTH characters" 6 40
                      else
                          echo ${remote_ssh_reciprocal_username}:${remote_ssh_reciprocal_password}::::/home/${remote_ssh_reciprocal_username}:bash | newusers
                          echo "$remote_ssh_username@$remote_ssh_domain $remote_ssh_port /home/$remote_ssh_username $remote_ssh_password" >> $FRIENDS_SERVERS_LIST
                          remote_ssh_username=""
                          remote_ssh_domain=""
                          remote_ssh_port=""
                          remote_ssh_password=""
                          remote_ssh_reciprocal_username=""
                          remote_ssh_reciprocal_password=""
                          entering_remote_backups_ctr=$((entering_remote_backups_ctr + 1))
                      fi
                  else
                      echo "$remote_ssh_username@$remote_ssh_domain $remote_ssh_port /home/$remote_ssh_username $remote_ssh_password" >> $FRIENDS_SERVERS_LIST
                      remote_ssh_username=""
                      remote_ssh_domain=""
                      remote_ssh_port=""
                      remote_ssh_password=""
                      remote_ssh_reciprocal_username=""
                      remote_ssh_reciprocal_password=""
                      entering_remote_backups_ctr=$((entering_remote_backups_ctr + 1))
                  fi
              else
                  echo "$remote_ssh_username@$remote_ssh_domain $remote_ssh_port /home/$remote_ssh_username $remote_ssh_password" >> $FRIENDS_SERVERS_LIST
                  remote_ssh_username=""
                  remote_ssh_domain=""
                  remote_ssh_port=""
                  remote_ssh_password=""
                  entering_remote_backups_ctr=$((entering_remote_backups_ctr + 1))
              fi

          fi
      else
          entering_remote_backups_done="yes"
      fi
  done
  if [ -f $FRIENDS_SERVERS_LIST ]; then
      chown $MY_USERNAME:$MY_USERNAME $FRIENDS_SERVERS_LIST
  fi
}

function show_result {
  clear
  if (( $entering_remote_backups_ctr < 2 )); then
      echo $'No remote backup locations were specified'
      exit 0
  fi
  if [ ! -f $FRIENDS_SERVERS_LIST ]; then
      echo $"No remote backups list found: $FRIENDS_SERVERS_LIST"
      exit 7358
  fi
  echo ''
  echo $"Remote backups list: $FRIENDS_SERVERS_LIST"
  echo ''
  echo $'Contents:'
  echo ''
  cat $FRIENDS_SERVERS_LIST
  echo ''
}

if [ ! $FRIENDS_SERVERS_LIST ]; then
    FRIENDS_SERVERS_LIST=/home/$MY_USERNAME/backup.list
fi

interactive_configuration_remote_backups
show_result
exit 0