#!/usr/bin/env bash

# ---
# - Script checks, if host declarations at (this) dhcp failover server
# - are in sync with primary dhcp server. If needed, dhcp failover server
# - will be updated.
# ---

src_host=gw-ah.kanzlei-kiel.netz

src_file_remote=/etc/dhcp/hosts.lan.conf
target_file_local=/etc/dhcp/hosts.lan.conf

# -------------
# --- Some functions
# -------------
echononl(){
   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$$
}

fatal(){
   echo ""
   echo -e "fatal error: $*"
   echo ""
   echo -e "\t\033[31m\033[1mInstalllation will be interrupted\033[m\033[m"
   echo ""
   exit 1
}

error(){
   echo ""
   echo -e "\t[ \033[31m\033[1mFehler\033[m ]: $*"
   echo ""
}

warn (){
   echo ""
   echo -e "\t[ \033[33m\033[1mWarning\033[m ]: $*"
   echo ""
}

info (){
   echo ""
   echo -e "\t[ \033[32m\033[1mInfo\033[m ]: $*"
   echo ""
}

echo_done() {
   echo -e "\033[80G[ \033[32mdone\033[m ]"
}
echo_ok() {
   echo -e "\033[80G[ \033[32mok\033[m ]"
}
echo_warning() {
   echo -e "\033[80G[ \033[33m\033[1mwarn\033[m ]"
}
echo_failed(){
   echo -e "\033[80G[ \033[1;31mfailed\033[m ]"
}
echo_skipped() {
   echo -e "\033[80G[ \033[33m\033[1mskipped\033[m ]"
}


# - Is this script running on terminal ?
# -
if [[ -t 1 ]] ; then
      terminal=true
else
   terminal=false
fi


# - Is this a systemd system?
# -
if [[ "X`which systemd`" = "X" ]]; then
   systemd_exists=false
else
   systemd_exists=true
fi

tmp_include_file="/tmp/$(basename $src_file_remote).$$"
tmp_err_msg=$(mktemp)

rsync -a -q -e ssh ${src_host}:${src_file_remote}  $tmp_include_file > $tmp_err_msg 2>&1
if [[ $? -ne 0 ]]; then
   if $terminal ; then
      error "$(cat $tmp_err_msg)"
   else
      echo -e "\n[ Error ]: $(cat $tmp_err_msg)"
   fi

   rm -f $tmp_include_file
   rm -f $tmp_err_msg
   exit 1
fi

diff $tmp_include_file $target_file_local > $tmp_err_msg 2>&1 
if [[ $? -ne 0 ]]; then
   cp -a $tmp_include_file $target_file_local
   if $systemd_exists ; then
      systemctl restart isc-dhcp-server > $tmp_err_msg 2>&1
      if [[ $? -ne 0 ]]; then
         if $terminal ; then
            error "$(cat $tmp_err_msg)"
         else
            echo -e "\n[ Error ]: $(cat $tmp_err_msg)"
         fi

         rm -f $tmp_include_file
         rm -f $tmp_err_msg
         exit 1
      else
         if $terminal ; then
            echo -e "\n\tUpdate was successfully done.\n"
         fi
      fi
   else
      /etc/init.d/isc-dhcp-server restart > $tmp_err_msg 2>&1 
      if [[ $? -ne 0 ]]; then
         if $terminal ; then
            error "$(cat $tmp_err_msg)"
         else
            echo -e "\n[ Error ]: $(cat $tmp_err_msg)"
         fi

         rm -f $tmp_include_file
         rm -f $tmp_err_msg
         exit 1
      else
         if $terminal ; then
            echo -e "\n\tUpdate was successfully done.\n"
         fi
      fi
   fi
else
   if $terminal ; then
      echo -e "\n\tServer is already up-to-date.\n"
   fi
fi

rm -f $tmp_include_file
rm -f $tmp_err_msg
exit 0