#!/bin/bash
# Author: Bandie <bandie@chaospott.de>
# License: GPL-3

QR_TEXT="Type \"qr\" for displaying the QR code on your command line only.\n"
STDOUT_TEXT="Type \"stdout\" to just put the string into stdout.\n"

function helpme() {
  echo "$0 [ Jabber ID ] [ Device ID ] [ Fingerprint ] [ [ Filename.png ] | [ qr ] | [ stdout ] ]"
  echo "You can use $0 without any arguments or put all the needed arguments in here."
  echo "Don't forget the quotation marks. ;)"
  echo "Requires qrencode and/or qr or even nothing."
  echo -e "\nExample:"
  echo -e "# $0 [ Jabber ID ] [ Device ID ] \"[ Fingerprint ]\" [ filename.png or \"qr\" or \"stdout\" ] "
  echo "# This will use qr to generate the QR code."
  echo -e "$0 bandie@example.com 9876543210 \"12345678 ABCDEF12 12345678 ABCDEF12 12345678 ABCDEF12 12345678 ABCDEF12\" qr"
  echo "# This will use qrencode to generate the QR code and will save it into foo.png"
  echo -e "$0 bandie@example.com 9876543210 \"12345678 ABCDEF12 12345678 ABCDEF12 12345678 ABCDEF12 12345678 ABCDEF12\" foo.png"
  echo "# This will put the string into stdout"
  echo -e "$0 bandie@example.com 9876543210 \"12345678 ABCDEF12 12345678 ABCDEF12 12345678 ABCDEF12 12345678 ABCDEF12\" stdout"
}

function gen() {

  if [[ "$3" =~ [G-Zg-z] ]]; then
    echo "$0: Error: This is not a valid fingerprint."
    exit 1
  fi

  FP=$(echo "$3" | sed 's/ //g' | tr '[:upper:]' '[:lower:]')
  OMEMOSTR="xmpp:$1?omemo-sid-$2=$FP"

  if [ -n "$QR" ]; then
    if [ "$4" = "qr" ]; then
      echo "$OMEMOSTR" | $QR
      exit 0
    fi
  fi
  if [ "$4" = "stdout" ]; then
    echo "$OMEMOSTR"
    exit 0
  fi
  if [ -n "$QRENCODE" ]; then
    echo "$OMEMOSTR" | $QRENCODE -s 5 -o "$4"
    exit 0
  fi
  
}

if [ "$1" = "-h" ] || [ "$1" = "--help" ]; then
  helpme
  exit 0
fi

export QR=$(which qr)
export QRENCODE=$(which qrencode)

if [ -z "$1" ]; then

  if [ -n "$QRENCODE" ]; then
    echo -en "Enter a filename.\n" 
  fi

  if [ -n "$QR" ]; then
    echo -en "$QR_TEXT"
  fi

  echo -en "$STDOUT_TEXT"

  if [ -n "$QRENCODE" ]; then
    echo -en "(output.png)"
  fi
  
  echo -en ": "
  read file

  if [ -z "$file" ]; then
    file="output.png"
  fi


  read -p "Enter your Jabber-ID (JID): " jid
  read -p "Enter your device ID: " did

  IFS="$(echo -e "\n")"
  read -p "Enter your fingerprint of this device: " fp

  gen "$jid" "$did" "$fp" "$file"
  exit 0

else 
  if [ -n "$2" ] && [ -n "$3" ] && [ -n "$4" ]; then
    gen "$1" "$2" "$3" "$4"
    exit 0
  else
    echo -e "$0: Error. To few arguments.\nTry running \"$0 --help\""
    exit 1
  fi
fi