#!/bin/bash
# -------
# File:        llxcfg-config
# Description: tool to manage llxcfg conffiles
# Author:      Luis Garcia Gisbert <garcia_luigis@gva.es>
#              (written for LliureX in June 2007)
# 
# 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"

# library
LLX_COMMONLIB="/usr/share/lliurex/llxcfg-common/llxcfg-common.sh"
[ -f "${LLX_COMMONLIB}" ] || exit 1
. ${LLX_COMMONLIB}

# variables
# ---------
declare -a CONF_DIRS
declare -a CONF_LIST
# more priority first
CONF_DIRS=("$LCFG_ADMIN_DIR" "$LCFG_PROGS_DIR" "$LCFG_STATIC_DIR")
BINARY="Y"
UNIQUE=""
SORT=""
NO_NEWLINES=""
# to store non-opt arguments
declare -a ARGV
# Bash arrays are 0-based, but we like ARGC to be equal to the number of non-option arguments.
# To solve this issue, we use a "C-like" ARGV vector by setting ARGV[0] with the name of script
# ('basename' of script for arbitrary cosmetic reasons), so real arguments begin with index 1
# the array will be ARGC+1 elements
ARGC=0
ARGV[0]="$(basename "$0")"


cfg_test0(){
   CFILE="$1"
   if [ -r "$CFILE" -a -s "$CFILE" ] ; then
      return 0
      # TODO Add more tests to guess the nature of the file ...
#      file "$CFILE" |grep -q " text$\| empty$\| (no magic)$" && return 0
   fi
   return 1
}

cfg_test(){
   [ -r "$1" ] || return 1
   return 0
}

get_relnames(){
   # find files, test for type "text" and remove pathname (with no loops)
   CFG_DIR="$1"
   if [ -d "${CFG_DIR}" ] ; then
      if [ -z "$BINARY" ] ; then
         file $(find "${CFG_DIR}" -xtype f) 2>/dev/null |sed -ne "/ text$\| empty$\| (no magic)$/{s%:.*$%%;s%^${CFG_DIR}%%p}" || true
      else
         find "${CFG_DIR}" -xtype f -printf "/%P\n"
      fi
   fi
   return 0
}

list_cfg_dir(){
   REL_DIR="$1"
   CFG_ACTION="$2"
   if [ "$REL_DIR" ] ; then
      REL_DIR="/$(echo "${REL_DIR}" |sed -e "s%/$%%;s%^/%%")"
   fi
   # create a tmp file with the list of files in every CONF_DIR level
   # in each list, the preceding lists (in the CONF_DIR hierarchy) are removed
   #
   # more utils power: 
   #      'sponge' allows pipes that read from and write to the same file, avoiding the use of 2 tempfiles
   #      'combine' merges files with a more readable syntax than an equivalent  diff/grep/sed pipeline

   i=0
   while [ $i -le ${#CONF_DIRS[@]} ] ; do
      j=0
      TMPFILE="$(tempfile)"
      get_relnames "${CONF_DIRS[$i]}${REL_DIR}" > "$TMPFILE"
      j=0
      while [ $j -lt $i ] ; do
         [ -s "${CONF_LIST[$j]}" ] && combine "$TMPFILE" not "${CONF_LIST[$j]}" |sponge "$TMPFILE"
         j=$(( $j + 1 ))
      done
      CONF_LIST[$i]="$TMPFILE"
      i=$(( $i + 1 ))
   done
   # add full path to file lists
   i=0
   while [ $i -le ${#CONF_DIRS[@]} ] ; do
      PRE_PATH="${CONF_DIRS[$i]}${REL_DIR}"
      TMPFILE="${CONF_LIST[$i]}"
      if [ -s "$TMPFILE" ] ; then
         case "$CFG_ACTION" in
            cat)
               cat $(sed -e "s%^%${PRE_PATH}%" "${TMPFILE}")
               ;;
            relative)
               cat "${TMPFILE}"
               ;;
            *)
               sed -e "s%^%${PRE_PATH}%" "${TMPFILE}"
               ;;
         esac 
      fi
      rm -f "$TMPFILE"
      i=$(( $i + 1 ))
   done
   return 0
}

list_cfg_filter(){
   FILTER=""
   FILTER2=""
   if [ "$SORT" ] ; then
      FILTER="sort"
   fi
   if [ "$UNIQUE" ] ; then
      FILTER="sort -u"
   fi
   if [ "$NO_NEWLINES" ] ; then
      FILTER2="tr '\n' ' '"
   fi
   if [ "$FILTER" -a "$NO_NEWLINES" ] ; then
      list_cfg_dir "$@" | $FILTER | tr '\n' ' '
   elif [ "$FILTER" ] ; then
      list_cfg_dir "$@" | $FILTER
   elif [ "$NO_NEWLINES" ] ; then
      list_cfg_dir "$@" | tr '\n' ' '
   else
      list_cfg_dir "$@"
   fi
}

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

usage() {
  CMD_NAME="$(basename "$0")"
  exit_message \
"Usage: $CMD_NAME [--binary|--text] {read|write|delete|filename} (RELATIVE)CONFFILE\n\
       $CMD_NAME [--binary|--text] [--unique|--sort] [ --no-newlines] dump (RELATIVE)CONFDIR\n\
       $CMD_NAME [--binary|--text] [--unique|--sort] [ --no-newlines] {list|listfiles} [(RELATIVE)CONFDIR]"
}


# ----
# main
# ----
while [ $# -ge 1 ] ; do
   case "$1" in
      --text|-t)
         BINARY=""
         ;;
      --binary|-b)
         BINARY="Y"
         ;;
      --sort|-s)
         SORT="Y"
         ;;
      --unique|-u)
         UNIQUE="Y"
         ;;
      --no-newlines|-n)
         NO_NEWLINES="Y"
         ;;
      read|write|delete|filename|dump|list|listfiles)
         ACTION="$1"
         ;;
      -*)
         # an invalid option -* or --* or a single -
         usage
         ;;
        *)
         ARGC=$(( $ARGC + 1 ))
         ARGV[$ARGC]="$1"
         ;;
     esac
     shift
done

[ -z "$ACTION" ] && usage
[ $ARGC -gt 1 ] && usage

case "$ACTION" in
   read|filename)
      [ $ARGC -lt 1 ] && usage
      CONFFILE="${ARGV[1]}"
      i=0
      rc=1
      while [ $i -le ${#CONF_DIRS[@]} ] ; do
         CFG_FILE="${CONF_DIRS[$i]}/${CONFFILE}"
         if cfg_test "${CFG_FILE}" ; then
            if [ "$ACTION" = "read" ] ; then
               cat "${CFG_FILE}" && rc=0
            else
               rc=0
               echo "${CFG_FILE}"
            fi
            break
         fi
         i=$(( $i + 1 ))
      done
      exit $rc
      ;;      
   write)
      [ $ARGC -lt 1 ] && usage
      CONFFILE="${ARGV[1]}"
      # we only write files at "LCFG_PROGS_DIR"
      TEXT_OPTION="--binary"
      [ -z "$BINARY" ] && TEXT_OPTION="--text"
      llxcfg-install --mode=${LLXCFG_MODE} --group=${LLXCFG_GROUP} ${TEXT_OPTION} - "${LCFG_PROGS_DIR}/${CONFFILE}" || exit_message "Error writing config file \"${LCFG_PROGS_DIR}/${CONFFILE}\""
      ;;
   delete)
      [ $ARGC -lt 1 ] && usage
      # we only delete files at "LCFG_PROGS_DIR"
      CONFFILE="${LCFG_PROGS_DIR}/${ARGV[1]}"
      rm -f "$CONFFILE"
      ;;
   dump)
      [ $ARGC -lt 1 ] && usage
      CONFDIR="${ARGV[1]}"
      list_cfg_filter "$CONFDIR" "cat"
      ;;
   list)
      CONFDIR="${ARGV[1]}"
      list_cfg_filter "$CONFDIR" "relative"
      ;;
   listfiles)
      CONFDIR="${ARGV[1]}"
      list_cfg_filter "$CONFDIR"
      ;;
   *)
      usage
      ;;
esac
exit 0