#!/bin/bash
# -------
# File:        llxcfg-archivevars
# Description: LliureX variables archiving tool
# 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="/usr/sbin:/usr/bin:/sbin:/bin"

# VARS
ARCHIVE_PATH="/backup/llxcfg/archive/vars"
ARCHIVE_MAIN="varset"
ARCHIVE_OLD="archive"
declare -a ARCHIVE_LIST
# funcs
# -----
error_message(){
   echo -e $1 >&2
   exit 1
}
usage(){
   SCRIPT_NAME="$(basename "$0")"
   error_message "${SCRIPT_NAME} VARSET {show|remove|test} [ -r REVISION ] [ VAR_1 [ ... VAR_N ]]\n\
${SCRIPT_NAME} VARSET archive-list\n\
${SCRIPT_NAME} VARSET {store|archive} VAR_1 [ ... VAR_N ]\n\
${SCRIPT_NAME} VARSET {store-all|archive-all}"
}

revision_list(){
   find "$ARCHIVE_PATH" -xtype f -name "${1}.${ARCHIVE_OLD}.*" |sort -u
}

# MAIN PROGRAM

VARS_LIB_FILE="/usr/sbin/llxcfg-vars.sh"
[ -e ${VARS_LIB_FILE} ] || error_message "Missing variable library file ${VARS_LIB_FILE}!!"
. ${VARS_LIB_FILE}

# Initial test

llxcfg_vars_test_CONFDIRS || error_message "Variables directory path error !!"
VARSET="$1"
[ "$VARSET" ] || usage
shift
ARCHIVE_ACTION="$1"
[ "$ARCHIVE_ACTION" ] || usage
if ! echo "$VARSET" |grep -q "^[[:alnum:]_-]\+$" ; then
   error_message "\"$VARSET\" is not a valid VARSET name"
fi
shift
if [ "$1" = "-r" ] ; then
   shift
   [ "$1" ] || usage
   NUMREV=$1
   shift
   [ ! $NUMREV -eq  0 ] || error_message "\"$NUMREV\" is not a valid revision number"
   ARCHIVE_LIST=($(revision_list "$VARSET"))
   NUM_ARCHIVE="${#ARCHIVE_LIST[@]}"
   if [ $NUMREV -gt 0 ] ; then
      INDEX_NUM=$(($NUMREV - 1))
   elif [ $NUMREV -lt 0 ] ; then
      INDEX_NUM=$(($NUM_ARCHIVE + $NUMREV))
   fi
   if [ $INDEX_NUM -ge $NUM_ARCHIVE ] || [ $INDEX_NUM -lt 0 ]; then
         error_message "\"$NUMREV\" is not a valid revision number"
   fi
   VARSET_FILE=${ARCHIVE_LIST[$INDEX_NUM]}
else
   VARSET_FILE="${ARCHIVE_PATH}/${VARSET}.${ARCHIVE_MAIN}"
fi
TIMESTAMP_FILE="${ARCHIVE_PATH}/${VARSET}.${ARCHIVE_OLD}.$(date +%Y%m%d-%H%M%S)"

case "$ARCHIVE_ACTION" in 
   store-all|archive-all)
      # force archive name
      VARSET_FILE="${ARCHIVE_PATH}/${VARSET}.${ARCHIVE_MAIN}"
      if [ "$ARCHIVE_ACTION" = "archive-all" -a -r "$VARSET_FILE" ] ; then
         mv "$VARSET_FILE" "$TIMESTAMP_FILE"
      fi
      llxcfg-listvars --values |llxcfg-install - "${VARSET_FILE}"
      ;;
   archive|store)
      [ "$1" ] || usage
      # force archive name
      VARSET_FILE="${ARCHIVE_PATH}/${VARSET}.${ARCHIVE_MAIN}"
      if [ "$ARCHIVE_ACTION" = "archive" -a -r "$VARSET_FILE" ] ; then
         mv "$VARSET_FILE" "$TIMESTAMP_FILE"
      fi
      llxcfg-showvars "$@" |llxcfg-install - "${VARSET_FILE}"
      ;;
   remove)
      rm -f "${VARSET_FILE}"
      ;;
   show)
      [ -r "${VARSET_FILE}" ] || error_message "There is not a VARSET named \"$VARSET\""
      if [ "$1" ] ; then
         llxcfg_vars_show "${VARSET_FILE}" "$@"
      else
         # all vars
         llxcfg_vars_show "${VARSET_FILE}" $(llxcfg_vars_names "${VARSET_FILE}")
      fi
      ;;
   test)
      [ -r "${VARSET_FILE}" ] || error_message "There is not a VARSET named \"$VARSET\""
      if [ -z "$1" ] ; then
         VAR_LIST="$(llxcfg_vars_names "${VARSET_FILE}")"
      else
         VAR_LIST="$@"
      fi
      # there is something to test ?
      [ "$VAR_LIST" ] || exit 0

      # read current values
      eval "$(llxcfg-showvars "$VAR_LIST")"
      for varname in $VAR_LIST ; do
         # preserve  current
         CURRENT_VALUE="${!varname}"
         # read old value (if any)
         eval "$(llxcfg_vars_show "${VARSET_FILE}" $varname)"
         [ "${!varname}" = "$CURRENT_VALUE" ] || exit 1
      done
      ;;
   archive-list)
      i=1
      for r in $(revision_list "$VARSET" |sed -e "s%^.*\.%%;") ; do
         echo -e "$i:\t$r"
         i=$(($i + 1))
      done
      ;;
   *)
      usage
      ;;
esac
exit 0