#!/usr/bin/env bash

script_name="$(basename $(realpath $0))"
working_dir="$(dirname $(realpath $0))"

conf_file="${working_dir}/conf/${script_name%%.*}.conf"

LOCK_DIR="/tmp/${script_name%%.*}.LOCK"
log_file="${LOCK_DIR}/${script_name%%.*}.log"


# ----------
# Base Function(s)
# ----------

usage() {


   [[ -n  "$1" ]] && error "$1"


   [[ $terminal ]] && echo -e "
\033[1mUsage:\033[m

   $(basename $0) [-b]

\033[1mDescription\033[m

   Script changes munin server ips (IPv4 and IPv6) in munin and in firewall configuration. All
   parameters can be given interactivly if not running in batch mode.

\033[1mOptions\033[m
   
   -b
      script acts in batch mode. All required parameters must be given in configuration filer

   -h
      Prints this help.

\033[1mFiles\033[m

   $conf_file: Configuration file

\033[1mExample:\033[m

   Change munin server ip addresses.

      \033[1m$(basename $0)\033[m

   Same, but act in batch mode

      \033[1m$(basename $0) -b\033[m

"

   clean_up 1

}

clean_up() {

   # Perform program exit housekeeping
   rm -rf "$LOCK_DIR"
   blank_line
   exit $1
}

echononl(){
   if $terminal ; then
      echo X\\c > /tmp/shprompt$$
      if [ `wc -c /tmp/shprompt$$ | awk '{print $1}'` -eq 1 ]; then
         echo -e -n "   $*\\c" 1>&2
      else
         echo -e -n "   $*" 1>&2
      fi
      rm /tmp/shprompt$$
   fi
}


fatal(){
   echo ""
   if $terminal ; then
      echo -e "   [ \033[31m\033[1mFatal\033[m ]: $*"
      echo ""
      echo -e "   \033[31m\033[1mScript was interupted\033[m!"
   else
      echo "   [ Fatal ]: $*"
      echo ""
      echo "              Script was terminated...."
   fi
   echo ""
   clean_up 1
}
error (){
   echo ""
   if $terminal ; then
      echo -e "   [ \033[31m\033[1mError\033[m ]: $*"
   else
      echo "[ Error ]: $*"
   fi
   echo ""
}

warn (){
   echo ""
   if $terminal ; then
      echo -e "   [ \033[33m\033[1mWarning\033[m ]: $*"
   else
      echo "[ Warning ]: $*"
   fi
   echo ""
}

warn_only_terminal () {
   if $terminal ; then
      echo ""
      echo -e "\t[ \033[33m\033[1mWarning\033[m ]: $*"
      echo ""
   fi
}

info (){
   if $terminal ; then
      echo ""
      echo -e "   [ \033[32m\033[1mInfo\033[m ]  $*"
      echo ""
   fi
}

ok (){
   if $terminal ; then
      echo ""
      echo -e "   [ \033[32m\033[1mOk\033[m ]    $*"
      echo ""
   fi
}

echo_done() {
   if $terminal ; then
      echo -e "\033[75G[ \033[32mdone\033[m ]"
   fi
}
echo_ok() {
   if $terminal ; then
      echo -e "\033[75G[ \033[32mok\033[m ]"
   fi
}
echo_warn() {
   if $terminal ; then
      echo -e "\033[75G[ \033[33mwarn\033[m ]"
   fi
}
echo_failed(){
   if $terminal ; then
      echo -e "\033[75G[ \033[1;31mfailed\033[m ]"
   fi
}
echo_skipped() {
   if $terminal ; then
      echo -e "\033[75G[ \033[90m\033[1mskipped\033[m ]"
   fi
}
echo_wait(){
   if $terminal ; then
      echo -en "\033[75G[ \033[5m\033[1m...\033[m ]"
   fi
}

trim() {
    local var="$*"
    var="${var#"${var%%[![:space:]]*}"}"   # remove leading whitespace characters
    var="${var%"${var##*[![:space:]]}"}"   # remove trailing whitespace characters
    echo -n "$var"
}

blank_line() {
   if $terminal ; then
      echo ""
   fi
}

containsElement () {
   local e
   for e in "${@:2}"; do [[ "$e" == "$1" ]] && return 0; done
   return 1
}

is_number() {

   return $(test ! -z "${1##*[!0-9]*}" > /dev/null 2>&1);

   # - also possible
   # -
   #[[ ! -z "${1##*[!0-9]*}" ]] && return 0 || return 1
   #return $([[ ! -z "${1##*[!0-9]*}" ]])
}

is_valid_ipv4() {
  local -a octets=( ${1//\./ } )
  local RETURNVALUE=0

  # return an error if the IP doesn't have exactly 4 octets
  [[ ${#octets[@]} -ne 4 ]] && return 1

  for octet in ${octets[@]}
  do
    if [[ ${octet} =~ ^[0-9]{1,3}$ ]]
    then # shift number by 8 bits, anything larger than 255 will be > 0
      ((RETURNVALUE += octet>>8 ))
    else # octet wasn't numeric, return error
      return 1
    fi
  done
  return ${RETURNVALUE}
}

# - Test if given argument is a valid IPv6 Address
# -
#is_valid_ipv6() {
#   local _ipv6=$1
#
#   if [ "$1" != "${1#[0-9a-f]*:}" ] \
#      && [ "$1" = "${1#*[^0-9a-f:]}" ] \
#      && [ "${1#*[0-9A-Fa-f][0-9A-Fa-f][0-9A-Fa-f][0-9A-Fa-f][0-9A-Fa-f]}" = "${1#*:*:*:*:*:*:*:*:*:}" ]; then
#      return 0
#   else
#      return 1
#   fi
#}
is_valid_ipv6() {
   local _ipv6="$1"

   _regex_ipv6='^([0-9a-fA-F]{0,4}:){1,7}[0-9a-fA-F]{0,4}$'


   if [[ "$_ipv6" =~ ${_regex_ipv6} ]]; then
      return 0
   else
      return 1
   fi
}



# ----------
# Some checks ..
# ----------

# - Running in a terminal?
# -
if [[ -t 1 ]] ; then
   terminal=true
else
   terminal=false
   BATCH_MODE=true
fi


# ----------
# Default Values
# ----------

BATCH_MODE=false

DEFAULT_MUNIN_CONF_FILE='/etc/munin/munin-node.conf'

DEFAULT_IPT_FIREWALL_MAIN_IPV4_FILE='/etc/ipt-firewall/main_ipv4.conf'
DEFAULT_IPT_FIREWALL_MAIN_IPV6_FILE='/etc/ipt-firewall/main_ipv6.conf'

# ----------
# Read Configuration
# ----------

if [[ -f "$conf_file" ]]; then
   source "$conf_file"
else
   warn_only_terminal "No configuration file '$conf_file' present.\n
                     Loading default values.."
fi


# ----------
# Read commandline parameter
# ----------

while getopts bh opt ; do
   case $opt in
      b)    BATCH_MODE=true
            ;;
      h)    usage
            ;;
      \?)   usage ;;
   esac
done

if [[ -n "${IPv4_ADDRESS_OLD}" ]] ; then 
   _IPv4_ADDRESS_OLD="${IPv4_ADDRESS_OLD}"
fi

if [[ -n "${IPv6_ADDRESS_OLD}" ]] ; then 
   _IPv6_ADDRESS_OLD="${IPv6_ADDRESS_OLD}"
fi

if [[ -n "${IPv4_ADDRESS_NEW}" ]] ; then 
   _IPv4_ADDRESS_NEW="${IPv4_ADDRESS_NEW}"
fi

if [[ -n "${IPv6_ADDRESS_NEW}" ]] ; then 
   _IPv6_ADDRESS_NEW="${IPv6_ADDRESS_NEW}"
fi

if [[ -z "${MUNIN_CONF_FILE}" ]]; then
   MUNIN_CONF_FILE="${DEFAULT_MUNIN_CONF_FILE}"
fi

if [[ -z "${IPT_FIREWALL_MAIN_IPV4_FILE}" ]]; then
   IPT_FIREWALL_MAIN_IPV4_FILE="${DEFAULT_IPT_FIREWALL_MAIN_IPV4_FILE}"
fi

if [[ -z "${IPT_FIREWALL_MAIN_IPV6_FILE}" ]]; then
   IPT_FIREWALL_MAIN_IPV6_FILE="${DEFAULT_IPT_FIREWALL_MAIN_IPV6_FILE}"
fi

if ${BATCH_MODE} && ( [[ -z "${IPv4_ADDRESS_OLD}" ]] || [[ -z "${IPv4_ADDRESS_NEW}" ]] \
                      || [[ -z "${IPv6_ADDRESS_OLD}" ]] || [[ -z "${IPv6_ADDRESS_NEW}" ]] ) ; then

   [[ -z "${IPv4_ADDRESS_OLD}" ]]  && fatal "Variable 'IPv4_ADDRESS_OLD' is empty and we are in batch mode!"
   [[ -z "${IPv4_ADDRESS_NEW}" ]]  && fatal "Variable 'IPv4_ADDRESS_NEW' is empty and we are in batch mode!"
   [[ -z "${IPv6_ADDRESS_OLD}" ]]  && fatal "Variable 'IPv6_ADDRESS_OLD' is empty and we are in batch mode!"
   [[ -z "${IPv6_ADDRESS_NEW}" ]]  && fatal "Variable 'IPv6_ADDRESS_NEW' is empty and we are in batch mode!"

   fatal "Something wired went wrong.."
fi

if ! ${BATCH_MODE} && ${terminal}; then
   echo ""
   echo -e "\033[32m--\033[m"
   echo ""
   echo "Insert IPv4-Address which do you want to change (old address)."
   echo ""
   echo -e "Type \"\033[33mNone\033[m\" if no IPv4 address should be changed."
   echo ""
   IPv4_ADDRESS_OLD=
   _set_ipv4=true
   while [ "X$IPv4_ADDRESS_OLD" = "X" ]; do

      if [[ -z "${_IPv4_ADDRESS_OLD}" ]]; then
         echononl "Old IPv4-Address: "

         read IPv4_ADDRESS_OLD

         ## - To lower case
         IPv4_ADDRESS_OLD=${IPv4_ADDRESS_OLD,,}

         if [ "X$IPv4_ADDRESS_OLD" = "X" ]; then
            echo -e "\n\t\033[33m\033[1mAn entry is required!\033[m\n"
            IPv4_ADDRESS_OLD=""
            continue
         fi

      else
         echononl "Old IPv4-Address: [${_IPv4_ADDRESS_OLD}]: "

         read IPv4_ADDRESS_OLD

         ## - To lower case
         IPv4_ADDRESS_OLD=${IPv4_ADDRESS_OLD,,}

         if [[ -z "$(trim ${IPv4_ADDRESS_OLD})" ]]; then
            IPv4_ADDRESS_OLD=${_IPv4_ADDRESS_OLD}
         fi
      fi

      if [ "${IPv4_ADDRESS_OLD,,}" = "none" ];then
         _set_ipv4=false
         break
      fi

      if ! is_valid_ipv4 $IPv4_ADDRESS_OLD ; then
         echo -e "\n\t\033[33m\033[1m$IPv4_ADDRESS_OLD\033[m is NOT a valid IPv4 Address\n"
         IPv4_ADDRESS_OLD=""
         continue
      fi
   done

   if $_set_ipv4 ; then
      echo ""
      echo -e "\033[32m--\033[m"
      echo ""
      echo "Insert IPv4-Address of the new munin server."
      echo ""

      IPv4_ADDRESS_NEW=

      while [ "X$IPv4_ADDRESS_NEW" = "X" ]; do


         if [[ -z "${_IPv4_ADDRESS_NEW}" ]]; then
            echononl "New IPv4-Address: "

            read IPv4_ADDRESS_NEW

            ## - To lower case
            IPv4_ADDRESS_NEW=${IPv4_ADDRESS_NEW,,}

            if [ "X$IPv4_ADDRESS_NEW" = "X" ]; then
               echo -e "\n\t\033[33m\033[1mAn entry is required!\033[m\n"
               IPv4_ADDRESS_NEW=""
               continue
            fi

         else

            echononl "New IPv4-Address [${_IPv4_ADDRESS_NEW}]: "

            read IPv4_ADDRESS_NEW
            
            ## - To lower case
            IPv4_ADDRESS_NEW=${IPv4_ADDRESS_NEW,,}

            if [[ -z "$(trim ${IPv4_ADDRESS_NEW})" ]]; then
               IPv4_ADDRESS_NEW=${_IPv4_ADDRESS_NEW}
            fi

         fi

         if ! is_valid_ipv4 $IPv4_ADDRESS_NEW ; then
            echo -e "\n\t\033[33m\033[1m$IPv4_ADDRESS_NEW\033[m is NOT a valid IPv4 Address\n"
            IPv4_ADDRESS_NEW=""
            continue
         fi
      done
   fi


   echo ""
   echo -e "\033[32m--\033[m"
   echo ""
   echo "Insert IPv6-Address which do you want to change (old address)."
   echo ""
   echo -e "Type \"\033[33mnone\033[m\" if no IPv6 address should be changed."
   echo ""
   IPv6_ADDRESS_OLD=
   _set_ipv6=true
   while [ "X$IPv6_ADDRESS_OLD" = "X" ]; do

      if [[ -z "${_IPv6_ADDRESS_OLD}" ]]; then
         echononl "Old IPv6-Address: "

         read IPv6_ADDRESS_OLD

         ## - To lower case
         IPv6_ADDRESS_OLD=${IPv6_ADDRESS_OLD,,}

         if [ "X$IPv6_ADDRESS_OLD" = "X" ]; then
            echo -e "\n\t\033[33m\033[1mAn entry is required!\033[m\n"
            IPv6_ADDRESS_OLD=""
            continue
         fi

      else
         echononl "Old IPv6-Address: [${_IPv6_ADDRESS_OLD}]: "

         read IPv6_ADDRESS_OLD

         ## - To lower case
         IPv6_ADDRESS_OLD=${IPv6_ADDRESS_OLD,,}

         if [[ -z "$(trim ${IPv6_ADDRESS_OLD})" ]]; then
            IPv6_ADDRESS_OLD=${_IPv6_ADDRESS_OLD}
         fi
      fi

      if [ "${IPv6_ADDRESS_OLD,,}" = "none" ];then
         _set_IPv6=false
         break
      fi

      if ! is_valid_ipv6 $IPv6_ADDRESS_OLD ; then
         echo -e "\n\tXX\033[33m\033[1m$IPv6_ADDRESS_OLD\033[mXX is NOT a valid IPv6 Address\n"
         IPv6_ADDRESS_OLD=""
         continue
      fi
   done

   if $_set_ipv6 ; then

      echo ""
      echo -e "\033[32m--\033[m"
      echo ""
      echo "Insert IPv6-Address iof the new munin server"
      echo ""

      IPv6_ADDRESS_NEW=


      while [ "X$IPv6_ADDRESS_NEW" = "X" ]; do


         if [[ -z "${_IPv6_ADDRESS_NEW}" ]]; then
            echononl "New IPv6-Address: "

            read IPv6_ADDRESS_NEW

            ## - To lower case
            IPv6_ADDRESS_NEW=${IPv6_ADDRESS_NEW,,}

            if [ "X$IPv6_ADDRESS_NEW" = "X" ]; then
               echo -e "\n\t\033[33m\033[1mAn entry is required!\033[m\n"
               IPv6_ADDRESS_NEW=""
               continue
            fi

         else

            echononl "New IPv6-Address [${_IPv6_ADDRESS_NEW}]: "

            read IPv6_ADDRESS_NEW
            
            ## - To lower case
            IPv6_ADDRESS_NEW=${IPv6_ADDRESS_NEW,,}

            if [[ -z "$(trim ${IPv6_ADDRESS_NEW})" ]]; then
               IPv6_ADDRESS_NEW=${_IPv6_ADDRESS_NEW}
            fi

         fi

         if ! is_valid_ipv6 $IPv6_ADDRESS_NEW ; then
            echo -e "\n\t\033[33m\033[1m$IPv6_ADDRESS_NEW\033[m is NOT a valid IPv6 Address\n"
            IPv6_ADDRESS_NEW=""
            continue
         fi
      done

   fi
fi

if ${terminal} ; then
   clear
   echo ""
   echo ""
   echo -e "\033[14G\033[32mReplace IP-Address(es) for munin server\033[m"
   echo ""

   if $_set_ipv4 ; then
      echo "   Old IPv4 Address...........................: $IPv4_ADDRESS_OLD"
      echo "   New IPv4 Address...........................: $IPv4_ADDRESS_NEW"
   else
      echo -e "   IPv4 Address(es)...........................: \033[33mNone\033[m"
   fi
   echo ""
   if $_set_ipv6 ; then
      echo "   Old IPv6 Address...........................: $IPv6_ADDRESS_OLD"
      echo "   New IPv6 Address...........................: $IPv6_ADDRESS_NEW"
   else
      echo -e "   IPv6 Address(es)........................: \033[33mNone\033[m"
   fi
   echo ""
   echo -e "   Munin Node configuration file..............: \033[33m${MUNIN_CONF_FILE}\033[m"
   echo -e "   ipt firewall main IPv4 file................: \033[33m${IPT_FIREWALL_MAIN_IPV4_FILE}\033[m"
   echo -e "   ipt firewall main IPv6 file................: \033[33m${IPT_FIREWALL_MAIN_IPV6_FILE}\033[m"

   if ! ${BATCH_MODE} ; then

      blank_line
      OK=
      while [ "$OK" != "yes" -o "$OK" != "no" ] ; do
         echononl "Parameters ok? [yes/no]: "
         read OK
         ## - To lower case
         OK=${OK,,}
         if [ "X$OK" = "X" ]; then
            echo -e "\n\t\033[33m\033[1mAn entry is required!\033[m\n"
            OK=""
            continue
         fi
         if [ "$OK" != "yes" -o "$OK" != "no" ] ; then
            break
         fi
         echo -e "\n\t\033[33m\033[1mWrong entry!\033[m\n"
      done
      [[ $OK = "yes" ]] || fatal Repeat execution with different parameters
   fi
fi

blank_line
blank_line


echononl "   Replace ${IPv4_ADDRESS_OLD} in file '${MUNIN_CONF_FILE}'.."
if [[ -f "${MUNIN_CONF_FILE}" ]] ; then
   if $(grep -q "${IPv4_ADDRESS_OLD}" "${MUNIN_CONF_FILE}" 2> /dev/null) ; then
      perl  -i -n -p -e "s#${IPv4_ADDRESS_OLD}#${IPv4_ADDRESS_NEW}#g" "${MUNIN_CONF_FILE}" > /dev/null 2>&1
      if [[  $? -gt 0 ]]; then
         echo_failed
      else
         echo_ok
      fi
   else
      echo_skipped
   fi
else
   echo_skipped
fi

echononl "   Replace ${IPv6_ADDRESS_OLD} in file '${MUNIN_CONF_FILE}'.."
if [[ -f "${MUNIN_CONF_FILE}" ]] ; then
   if $(grep -q "${IPv6_ADDRESS_OLD}" "${MUNIN_CONF_FILE}" 2> /dev/null) ; then
      perl  -i -n -p -e "s#${IPv6_ADDRESS_OLD}#${IPv6_ADDRESS_NEW}#g" "${MUNIN_CONF_FILE}" > /dev/null 2>&1
      if [[  $? -gt 0 ]]; then
         echo_failed
      else
         echo_ok
      fi
   else
      echo_skipped
   fi
else
   echo_skipped
fi


echononl "   Replace ${IPv4_ADDRESS_OLD} in file '${IPT_FIREWALL_MAIN_IPV4_FILE}'.."
if [[ -f "${IPT_FIREWALL_MAIN_IPV4_FILE}" ]] ; then
   if $(grep -q -E "munin_remote_ip=\"?${IPv4_ADDRESS_OLD}\"?" "${IPT_FIREWALL_MAIN_IPV4_FILE}" 2> /dev/null) ; then
      perl  -i -n -p -e "s#munin_remote_ip=\"?${IPv4_ADDRESS_OLD}\"?#munin_remote_ip=\"${IPv4_ADDRESS_NEW}\"#g" "${IPT_FIREWALL_MAIN_IPV4_FILE}" > /dev/null 2>&1
      if [[  $? -gt 0 ]]; then
         echo_failed
      else
         echo_ok
      fi
   else
      echo_skipped
   fi
else
   echo_skipped
fi

echononl "   Replace ${IPv6_ADDRESS_OLD} in file '${IPT_FIREWALL_MAIN_IPV6_FILE}'.."
if [[ -f "${IPT_FIREWALL_MAIN_IPV6_FILE}" ]] ; then
   if $(grep -q -E "munin_remote_ip=\"?${IPv6_ADDRESS_OLD}\"?" "${IPT_FIREWALL_MAIN_IPV6_FILE}" 2> /dev/null) ; then
      perl  -i -n -p -e "s#munin_remote_ip=\"?${IPv6_ADDRESS_OLD}\"?#munin_remote_ip=\"${IPv6_ADDRESS_NEW}\"#g" "${IPT_FIREWALL_MAIN_IPV6_FILE}" > /dev/null 2>&1
      if [[  $? -gt 0 ]]; then
         echo_failed
      else
         echo_ok
      fi
   else
      echo_skipped
   fi
else
   echo_skipped
fi

clean_up 0