#!/bin/sh
HGTMP=""
cleanup_exit() {
    rm -rf "$HGTMP"
}
# Remove temporary files even if we get interrupted
trap "cleanup_exit" 0 # normal exit
trap "exit 255" HUP INT QUIT ABRT TERM
HGTMP=$(mktemp -d "${TMPDIR-/tmp}/hgeditor.XXXXXX")
if [ -z "$HGTMP" ] || ! [ -d "$HGTMP" ]; then
    echo "Could not create temporary directory! Exiting." 1>&2
    exit 1
fi
LINE=$(fgrep 'HG: --- 8< ---' -nm1 "$1" | cut -d: -f1)
if [ -n "$LINE" ]; then
    head -n "$(( LINE - 1 ))" "$1" > "$HGTMP/msg"
    tail -n +"$(( LINE + 1 ))" "$1" | sed -e 's/^HG: //g' > "$HGTMP/diff"
else
    cat "$1" > "$HGTMP/msg"
fi
MD5=$(which md5sum 2>/dev/null) || \
    MD5=$(which md5 2>/dev/null)
[ -x "${MD5}" ] && CHECKSUM=$(${MD5} "$HGTMP/msg")
if [ -s "$HGTMP/diff" ]; then
    vim -f "+e $HGTMP/diff" '+set buftype=help filetype=diff' "+vsplit $HGTMP/msg" '+setlocal spell' || exit $?
else
    vim -f "$HGTMP/msg" '+setlocal spell' || exit $?
fi
[ -x "${MD5}" ] && (echo "$CHECKSUM" | ${MD5} -c >/dev/null 2>&1 && exit 13)
mv "$HGTMP/msg" "$1"
exit $?