#!/bin/sh
#
# This is an example of using HGEDITOR to create of diff to review the
# changes while commiting.

# If you want to pass your favourite editor some other parameters
# only for Mercurial, modify this:
case "${EDITOR}" in
   "")
       EDITOR="vi"
       ;;
   emacs)
       EDITOR="$EDITOR -nw"
       ;;
   gvim|vim)
       EDITOR="$EDITOR -f -o"
       ;;
esac


HGTMP=""
cleanup_exit() {
   rm -rf "$HGTMP"
}

# Remove temporary files even if we get interrupted
trap "cleanup_exit" 0 # normal exit
trap "exit 255" 1 2 3 6 15 # HUP INT QUIT ABRT TERM

HGTMP="${TMPDIR-/tmp}/hgeditor.$RANDOM.$RANDOM.$RANDOM.$$"
(umask 077 && mkdir "$HGTMP") || {
   echo "Could not create temporary directory! Exiting." 1>&2
   exit 1
}

(
   grep '^HG: changed' "$1" | cut -b 13- | while read changed; do
       "$HG" diff "$changed" >> "$HGTMP/diff"
   done
)

cat "$1" > "$HGTMP/msg"

MD5=$(which md5sum 2>/dev/null) || \
   MD5=$(which md5 2>/dev/null)
[ -x "${MD5}" ] && CHECKSUM=`${MD5} "$HGTMP/msg"`
if [ -s "$HGTMP/diff" ]; then
   $EDITOR "$HGTMP/msg" "$HGTMP/diff" || exit $?
else
   $EDITOR "$HGTMP/msg" || exit $?
fi
[ -x "${MD5}" ] && (echo "$CHECKSUM" | ${MD5} -c >/dev/null 2>&1 && exit 13)

mv "$HGTMP/msg" "$1"

exit $?