#!/bin/bash
# -------
# File:        llxcfg-netconfig-client
# Description: LliureX netconfig client utility
# Author:      Luis Garcia Gisbert <garcia_luigis@gva.es>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin St, Fifth Floor, Boston MA 02110-1301 USA
# --------

set -e

# PATH y variables
PATH="/sbin:/bin:/usr/sbin:/usr/bin"
VAR_LIST="NETCFG_URL"
LLX_GETVAR="/usr/sbin/llxcfg-showvars"

NETCFG_PATH="/var/lib/netconfig-client"
NETCFG_DOWNLOAD_DIR="download"
NETCFG_DATA_DIR="data"

# wget parameters
WGET_TRIES=3
WGET_TIMEOUT=10
# ajusta el comando para descargar
WGET_CMD="/usr/bin/wget -nc -q -t ${WGET_TRIES} -T ${WGET_TIMEOUT} -O"

# Funcs

error_message(){
   echo -e "$1" >&2
}

exit_message(){
   error_message "$1"
   exit 1
}

wget_file(){
   GET_RC=0
   printf "Trying to download ${1} ... "
   ${WGET_CMD} "${2}" "${1}" &>/dev/null || GET_RC=$?
   if [ $GET_RC -eq 0 ] ; then
      echo "[OK]"
   else
      echo "[*fail*]"
   fi
   return $GET_RC
}

extract_data(){
   [ -r "${TARBALL_FILE}" ] || return 1
   if ! tar -C "${TARBALL_DATA}/" -xf "${TARBALL_FILE}" &>/dev/null ; then
      error_message "Error extracting downloaded data"
      remove_tarball_data
      remove_data fail
      return 1
   fi
   llxcfg-ncfg-scripts post-load || true
   return 0 
}

remove_tarball_data(){
   rm -fr $(find "${TARBALL_DATA}/" -maxdepth 1 -mindepth 1)
}

remove_data(){
   case $1 in
      pre-load|revert)
         llxcfg-ncfg-scripts pre-load || true
         rm -f "${TARBALL_FILE}"
         remove_tarball_data
         ;;
      fail)
         rm -f "${TARBALL_FILE}"
         llxcfg-ncfg-scripts fail || true
         ;;
      *)
         return 1
         ;;
   esac
   return 0
}

get_data(){
   [ "${NETCFG_URL}" ] || return 0
   # Get remote md5sum
   DOWNLOAD_STATUS="READY"
   if [ -d "${TARBALL_DATA}" ] ; then
      # check md5sum
      MD5NEW="$(tempfile)"
      rm -f "${MD5NEW}"
      if wget_file "${NETCFG_URL}.list" "${MD5NEW}" ; then
         MD5OLD="$(tempfile)"
         ( cd ${TARBALL_DATA}; find -xtype f -exec md5sum {} \; ) |sort > "${MD5OLD}"
         if diff -q "$MD5OLD" "$MD5NEW" &>/dev/null ; then
            DOWNLOAD_STATUS="NO-CHANGES"
            echo "No changes found in ${NETCFG_URL}."
         fi
         rm -f "$MD5OLD"
      else
         DOWNLOAD_STATUS="FAIL"
      fi
      rm -f "$MD5NEW"
   fi
   if [ "$DOWNLOAD_STATUS" = "NO-CHANGES" ] ; then
      # do not remove, nor extract but re-execute scripts
      echo "Running 'post-load' scripts"
      llxcfg-ncfg-scripts post-load || true
      return 0
   fi
   remove_data pre-load
   if [ "$DOWNLOAD_STATUS" = "READY" ] ; then
      wget_file "${NETCFG_URL}" "${TARBALL_FILE}" || DOWNLOAD_STATUS="FAIL"
   fi
   if [ "$DOWNLOAD_STATUS" = "FAIL" ] ; then
      remove_data fail
      error_message "Configuration update from ${NETCFG_URL} FAILED"
      return 1
   fi
   extract_data || return 1
   echo "Configuration SUCCESSFULLY updated from ${NETCFG_URL}"
   return 0
}

usage() {
  exit_message "Usage: $0 {get-data|remove-data}\n\
       $0 {getdirs|getfiles} [NAME]"
}


# main

# libs
LIB_FILE="/usr/share/lliurex/llxcfg-netconfig/llxcfg-netconfig.sh"
[ -e ${LIB_FILE} ] || exit_message "Missing variable library file ${LIB_FILE}!!"
. ${LIB_FILE}

TARBALL_FILE="${NETCFG_PATH}/${NETCFG_DOWNLOAD_DIR}/${NETCFG_TARBALL}"
TARBALL_DATA="${NETCFG_PATH}/${NETCFG_DATA_DIR}"

# read vars
[ -x ${LLX_GETVAR} ] && eval `${LLX_GETVAR} ${VAR_LIST}`

rc=0
DATA_FIND_OPTIONS="${NETCFG_PATH}/${NETCFG_DATA_DIR}/ -maxdepth 1  -mindepth 1 -type d"
[ -z "$2" ] || DATA_FIND_OPTIONS="$DATA_FIND_OPTIONS -name $2"

case "$1" in
   get-data)
      get_data || rc=$?
      ;;
   remove-data)
      remove_data revert || rc=$?
      ;;
   getdirs)
      find $DATA_FIND_OPTIONS
      ;;
   getfiles)
      find $DATA_FIND_OPTIONS -exec find {} -xtype f \;
      ;;
   *)
      usage
      ;;
esac

exit $rc