#!/usr/bin/env bash

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

conf_file="${working_dir}/conf/${script_name%%.*}.conf"
LOCK_DIR="$(mktemp -d)"


# ----------
# Base Function(s)
# ----------
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 ] $*"
   else
      echo -e "   [ Fatal ] $*"
   fi
   echo ""
   if $terminal ; then
      echo -e "             \033[1mScript terminated\033[m.."
   else
      echo -e "             Script terminated.."
   fi
   echo ""
   rm -rf $LOCK_DIR
   exit 1
}

error (){
   echo ""
   if $terminal ; then
      echo -e "   [ \033[31m\033[1mError\033[m ] $*"
   else
      echo "   [ Error ] $*"
   fi
   echo ""
}

warn (){
   if $LOGGING || $terminal ; then
      echo ""
      if $terminal ; then
         echo -e "   [ \033[33m\033[1mWarn\033[m ]  $*"
      else
         echo "   [ Warn ]  $*"
      fi
      echo ""
   fi
}

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

ok (){
   if $LOGGING || $terminal ; then
      echo ""
      if $terminal ; then
         echo -e "   [ \033[32m\033[1mOk\033[m ]    $*"
      else
         echo "   [ Ok ]    $*"
      fi
      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_failed(){
   if $terminal ; then
      echo -e "\033[75G[ \033[1;31mfailed\033[m ]"
   fi
}
echo_skipped() {
   if $terminal ; then
      echo -e "\033[75G[ \033[33m\033[1mskipped\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
}

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]*}" ]])
}

## - Check if a given array (parameter 2) contains a given string (parameter 1)
## -
containsElement () {
   local e
   for e in "${@:2}"; do [[ "$e" == "$1" ]] && return 0; done
   return 1
}




# ----------
# - Jobhandling 
# ----------

# - Run 'clean_up' for signals SIGHUP SIGINT SIGTERM
# -
trap clean_up SIGHUP SIGINT SIGTERM


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

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


# ==========
# - Begin Main Script
# ==========

# ----------
# - Headline
# ----------

if $terminal ; then
   echo ""
   echo -e "\033[1m----------\033[m"
   echo -e "\033[32m\033[1mRunning script \033[m\033[1m$script_name\033[32m .. \033[m"
   echo -e "\033[1m----------\033[m"
fi


# ----------
#  Read Configurations from $conf_file
# ----------

if [[ -f "$conf_file" ]]; then
   source "$conf_file"
else
   fatal "No configuration file '$conf_file' present!"
fi

if [[ -z "$LOCAL_DOMAIN" ]] ; then
   fatal "Local domain (Variable 'LOCAL_DOMAIN') not given!"
fi

if [[ -z "$HOSTNAME_PREFIX" ]] ; then
   fatal "Hostname prefix not given. (Variable 'HOSTNAME_PREFIX')"
fi

if [[ -z "$FIRST_PC_NUM" ]] ; then
   fatal "First PC number not given (Variable 'FIRST_PC_NUM')"
fi

if [[ -z "$LAST_PC_NUM" ]] ; then
   fatal "Last PC number not given (Variable 'LAST_PC_NUM')"
fi

declare -a pc_numbers_arr=()
if [[ -n "$PC_NUMBERS_PRESENT" ]] ; then
   for _number in $PC_NUMBERS_PRESENT ; do
      if is_number $_number ; then
         pc_numbers_arr+=($_number)
      fi
   done
fi



declare -i nr=$FIRST_PC_NUM
blank_line
while [[ $nr -le $LAST_PC_NUM ]] ; do
   if [[ ${#pc_numbers_arr[@]} -gt 0 ]] ; then
      if ! containsElement $nr ${pc_numbers_arr[@]} ; then
         let nr++
         continue
      fi
   fi

   ping -n -c 2 -q ${HOSTNAME_PREFIX}${nr}.$LOCAL_DOMAIN > /dev/null 2>&1
   if [[ $? -eq 0 ]]; then
      if $terminal ; then
         echo -e "\t${HOSTNAME_PREFIX}${nr}.${LOCAL_DOMAIN}: \033[32m\033[1monline\033[m"
      else
         echo "   ${HOSTNAME_PREFIX}${nr}.${LOCAL_DOMAIN}: online"
      fi
   else
      if $terminal ; then
         echo -e "\t${HOSTNAME_PREFIX}${nr}.${LOCAL_DOMAIN}: \033[31m\033[1moffline\033[m"
      else
         echo "   ${HOSTNAME_PREFIX}${nr}.${LOCAL_DOMAIN}: offline"
      fi
   fi

   let nr++

done

blank_line
clean_up 0