#!/bin/bash
#

set -e

# variables

BEGIN_LLIUREX="#--LLXCFG_INI--#"
END_LLIUREX="#--LLXCFG_END--#"
COMMENT_LLIUREX="####--COMMENT-BY-LLXCFG--####"
INCLUDE_LLIUREX_CONF="include \"/etc/bind/named.conf.lliurex\";"
SKEL_ROOT="./skel"
BIND_DIR="/etc/bind"
CONF_DIR="dns/bind"
DB_SRV_ALIAS="${BIND_DIR}/db.aula.srv-alias"
DB_HOSTS="${BIND_DIR}/db.aula.hosts"
DB_HOSTS_REVERSE="${BIND_DIR}/db.aula.hosts.reverse"
DB_HOSTS_UNREG="${BIND_DIR}/db.aula.hosts-unreg"
DB_HOSTS_UNREG_REVERSE="${BIND_DIR}/db.aula.hosts-unreg.reverse"
DB_SRV_REVERSE="${BIND_DIR}/db.aula.server.reverse"
CONF_LOCAL="${BIND_DIR}/named.conf.local"
ALL_ALIAS=""

VAR_LIST="SRV_DOMAIN DNS_EXTERNAL_NS SRV_BITMASK SRV_IP"
LLX_GETVAR="/usr/sbin/llxcfg-showvars"

# libreria
LIB_FILE="/usr/share/lliurex/lliurex-srv-common/lliurex-netfuncs.sh"
[ -e "$LIB_FILE" ] || exit 1
. $LIB_FILE

gen_conf_local(){
  llxcfg-cpkg plainview "$CONF_LOCAL" || exit 1
  cat << EOF
// $BEGIN_LLIUREX
// Please, do not remove next line
$INCLUDE_LLIUREX_CONF
// $END_LLIUREX
EOF
}

dbgen_server_alias(){
   for a in $SRV_ALIASES ; do
      [ "$a" != "server" ] && echo -e "$a\tIN\tCNAME\tserver"
   done
}

dbgen_server_reverse(){
   echo -e "$(ip_reverse "${SRV_IP}" ${REVERSE_BYTES})\tIN\tPTR\tserver.${SRV_DOMAIN}."
}


dbgen_hosts(){
   HOST_NUM=1
   HOST_MAX=`get_dhcp_host_max`
   HOST_IP_LIST="`get_dhcp_host_address 1 ${HOST_MAX}`"
   for HOST_IP in ${HOST_IP_LIST}; do
      HOST_NAME="`get_dhcp_host_name ${HOST_NUM}`"
      echo -e "$(ip_reverse "${HOST_IP}" ${REVERSE_BYTES})\tIN\tPTR\t${HOST_NAME}.${SRV_DOMAIN}." >> "${SKEL_ROOT}/${DB_HOSTS_REVERSE}"
      echo -e "${HOST_NAME}\tIN\tA\t${HOST_IP}" >> "${SKEL_ROOT}/${DB_HOSTS}"
      HOST_ALIAS="`get_dhcp_host_alias ${HOST_NUM}`"
      for alias in ${HOST_ALIAS}; do
         if ! echo " $HOST_NAME $ALL_ALIAS " |grep -q " $alias " ; then
            echo -e "${alias}\tIN\tCNAME\t${HOST_NAME}" >> "${SKEL_ROOT}/${DB_HOSTS}"
            ALL_ALIAS="$ALL_ALIAS $alias"
         fi
      done
      HOST_NUM=$((${HOST_NUM}+1))
   done
}

dbgen_hosts_unreg(){
   HOST_LIST=`get_noreg_host_list`
   for h in ${HOST_LIST}; do
      HOST_NAME="`echo ${h} |cut -f 1 -d ,`"
      HOST_IP="`echo ${h} |cut -f 2 -d ,`"
      echo -e "${HOST_NAME}\tIN\tA\t${HOST_IP}" >> "${SKEL_ROOT}/${DB_HOSTS_UNREG}"
      echo -e "$(ip_reverse "${HOST_IP}" ${REVERSE_BYTES})\tIN\tPTR\t${HOST_NAME}.${SRV_DOMAIN}." >> "${SKEL_ROOT}/${DB_HOSTS_UNREG_REVERSE}"
   done
}

########
# main #
########

# lee DNS_DOMAIN y DNS_EXTERNAL_NS y VHOST_NAMES
[ -x ${LLX_GETVAR} ] && eval `${LLX_GETVAR} ${VAR_LIST}`
SRV_ALIASES="$(get_dhcp_host_alias 0)"
ALL_ALIAS="$SRV_ALIASES"

# calculate num of bytes for reverse resolution
REVERSE_BYTES=$((4 - $SRV_BITMASK/8))

# search required lliurex line in named.conf.local
if [ ! -f "$CONF_LOCAL" ] || ! grep -q "^${INCLUDE_LLIUREX_CONF}$" "$CONF_LOCAL" ; then
  gen_conf_local |skel-install "${CONF_LOCAL}"
fi

# generate template files from llxcfg conffiles
for f in $(llxcfg-config list "$CONF_DIR") ; do
   llxcfg-config read "$CONF_DIR/$f" | skel-install -t "${BIND_DIR}/${f}"
done

# generate server-alias db
dbgen_server_alias |skel-install "${DB_SRV_ALIAS}"

# generate server-reverse db
dbgen_server_reverse |skel-install "${DB_SRV_REVERSE}"

#generate hosts db

:> "${SKEL_ROOT}/${DB_HOSTS}"
:> "${SKEL_ROOT}/${DB_HOSTS_REVERSE}"
dbgen_hosts

#generate unreg hosts db
:> "${SKEL_ROOT}/${DB_HOSTS_UNREG}"
:> "${SKEL_ROOT}/${DB_HOSTS_UNREG_REVERSE}"
dbgen_hosts_unreg

exit 0