#!/bin/bash

FC=($(fedpkg verrel | awk -F. '{print $NF}'))

SRC=($(ls config-* 2>/dev/null))

TGT=($(ls kernel-*.$FC/linux-*.$2/configs/kernel-*-*.config \
          kernel-*.$FC/linux-*.$2/configs/kernel-*-*-debug.config 2>/dev/null))
TGT1=(${TGT[*]#kernel-*.$FC/linux-*.$2/configs/kernel-*-})

ALL_OPTS="cdfimn"

if [ $# -lt 2 ] ; then
   echo -e "Usage:\n   $(basename $0) [-$ALL_OPTS] input target\n"
   echo -e " Sort input config file into the same order as the target\n"
   echo -e "      -c: insert comments about non-matching/impossible items"
   echo -e "      -d: show raw unsorted output with extra debug text"
   echo -e "      -f: force output to match what is in the target config,"
   echo -e "          and/or remove impossible config items"
   echo -e "      -i: find impossible config items"
   echo -e "      -m: find changed config items"
   echo -e "      -n: do not sort output\n"
   echo -e "   input: source config file" ' [' "${SRC[*]#config-}" ']\n'
   echo -e "  target: output arch name" ' [' "${TGT1[*]%.config}" ']\n'
   exit 1
fi

while getopts "$ALL_OPTS" OPTION ; do
case $OPTION in
c)
   ADDCOMMENT=1 ;;
d)
   DEBUG=1 ;;
f)
   FORCE=1 ;;
i)
   FIND_IMPOSS=1 ;;
m)
   FIND_CHANGED=1 ;;
n)
   NOSORT=1 ;;
\?)
   exit 2 ;;
esac
done

if [ "$FORCE" -a "$ADDCOMMENT" ] ; then
	echo "-f and -c options cannot be used together"
	exit 2
fi

shift $((OPTIND-1))

TEMPFILES="xx00 xx01 xx98 xx99"
TEMPLEFT=
for FILE in $TEMPFILES ; do
   [ -f "$FILE" ] && TEMPLEFT="Y"
done
if [ "$TEMPLEFT" ] ; then
   echo "WARNING! Output files named xx?? already exist." >&2
   read -p "Press <Enter> to erase files, or Ctrl-C to exit..."
   echo >&2
fi
rm -f $TEMPFILES

SRCFILE=config-$1
[ ! -f $SRCFILE ] && echo "Input file" $SRCFILE "missing" && exit 2

TGTFILE=kernel-*.$FC/linux-*.$2/configs/kernel-*-$2.config
[ ! -f $TGTFILE ] && echo "No target file matching" $TGTFILE "exists" && exit 2

[ "$FIND_IMPOSS" ] && \
   find kernel-*.$FC/*.$2 -name Kconfig\* -type f \
   | xargs egrep -s -h '^[[:space:]]*(menu)?config[[:space:]]+' \
   | sed -r 's/^[[:space:]]*(menu)?config[[:space:]]+/CONFIG_/' \
   | sort | uniq >xx98

extract_optname() {
         # extract the option name from $TEXT, setting $OPTNAME
         OPTNAME=
         if [ "${TEXT:0:7}" = "CONFIG_" ] ; then
            OPTNAME=${TEXT%%=*}
         elif [ "${TEXT:0:9}" = "# CONFIG_" ] ; then
            OPTNAME=${TEXT%" is not set"}
            OPTNAME=${OPTNAME#\# }
         fi
}

print_saved_comments() {
      if [ $IX -gt 0 ] ; then
         [ "$DEBUG" ] && echo "            ->" $IX "comments were saved"
         (( IX-- ))
         for IX in $(seq 0 $IX) ; do
            echo "$LINE":"${SAVECOMMENT[$IX]}"
         done
         unset SAVECOMMENT
         IX=0
      fi
}

assign_line_number() {
      # use input line numbers if not sorting
      [ "$NOSORT" ] && LINE=$IN
      # make sure it has a line number
      [ -z "$LINE" ] && LINE=999999
}

IX=0
IN=0
declare -a SAVECOMMENT

cat ${SRCFILE} | {
while read TEXT ; do

   LINE=
   COMMENT=

   # replace empty lines
   [ -z "$TEXT" ] && TEXT='//'

   if [ "${TEXT:0:7}" = "CONFIG_" -o "${TEXT:0:9}" = "# CONFIG_" ] ; then

      LINE=$(grep -n "^$TEXT" $TGTFILE | head -1 | cut -f 1 -d ':')
      if [ -z "$LINE" ] ; then
         [ "$DEBUG" ] && echo "nofind      ->" "$TEXT"

         extract_optname
         if [ "$OPTNAME" ] ; then

            if [ "$FIND_CHANGED" ] ; then
               for FINDTEXT in "^${OPTNAME}=" "^# ${OPTNAME} is not set" ; do
                  if [ -z "$LINE" ] ; then
                     [ "$DEBUG" ] && echo "looking for ->" "$FINDTEXT"
                     LINE=$(grep -n "$FINDTEXT" $TGTFILE | head -1 | cut -f 1 -d ':')
                     if [ "$LINE" ] ; then
                        CHANGED=$(grep "$FINDTEXT" $TGTFILE | head -1)
                        if [ "$FORCE" ] ; then
                           TEXT=$CHANGED
                           [ "$DEBUG" ] && echo 'forced      ->' "$TEXT"
                        else
                           if [ "$ADDCOMMENT" ] ; then
                              if [ ${CHANGED:0:1} = '#' ] ; then
                                 NEWOPT="not set"
                              else
                                 NEWOPT=${CHANGED#$OPTNAME}
                              fi
                              COMMENT="# -- Next option changed to \"${NEWOPT}\" at target line $LINE --"
                           fi
                        fi
                     fi
                  fi
               done
            fi

            if [ "$FIND_IMPOSS" -a -z "$LINE" -a -z "$COMMENT" ] ; then
               POSSIBLE=$(grep -n "^$OPTNAME" xx98)
               if [ -z "$POSSIBLE" ] ; then
                  if [ "$ADDCOMMENT" ] ; then
                     COMMENT="# -- Next option is impossible --"
                  elif [ "$FORCE" ] ; then
                     [ "$DEBUG" ] && echo 'impossible  ->' "$TEXT"
                     TEXT=""
                  fi
               fi
            fi

         fi

      fi

   else
      # not a config variable
      COMMENT="$TEXT"
      TEXT=
   fi

   [ "$DEBUG" -a "$COMMENT" ] && echo "comment     ->" "$LINE" "$COMMENT"
   [ "$DEBUG" -a "$TEXT" ]    && echo "text        ->" "$LINE" "$TEXT"

   if [ "$TEXT" ] ; then

      assign_line_number

      # print the saved comments first
      print_saved_comments
      # now print the latest comment and text
      [ "$COMMENT" ] && echo "$LINE":"$COMMENT"
      echo "$LINE":"$TEXT"

   elif [ "$COMMENT" ] ; then

      # no output yet, save the comment
      SAVECOMMENT[$IX]="$COMMENT"
      let IX++
      [ "$DEBUG" ] && echo 'savecomment (#'${IX}')'

   fi

   let IN++

done
# flush the buffers
assign_line_number
print_saved_comments
[ "$DEBUG" ] && echo "$IN lines read from input"
} >xx99

if [ "$DEBUG" ] ; then
   # just show the raw output with debug info, then exit
   cat xx99
else

   # split output into two files, for matched and unmatched items
   cat xx99 | sort -s -t ":" -k 1g | csplit -k -s - /^999999/ 2>/dev/null

   cat xx00 | cut -f 2- -d ':' | sed 's/^\/\/$//'
   if [ -s xx01 ] ; then
      echo
      echo '# ------------  UNMATCHED OPTIONS  ------------'
      echo
      cat xx01 | cut -f 2- -d ':' | sed 's/^\/\/$//'
   fi

fi

rm -f $TEMPFILES