#!/bin/bash
set -e
set -o pipefail

kind="$1"

desc=`git describe --always HEAD`
log=`git log -1 --pretty='format:%h' HEAD`
date=`date --iso-8601=minutes`
set +e
git diff --quiet HEAD
diffrc=$?
set -e
case $diffrc in
0)	;;
1)	diffplus=+ ;;
*)	exit $diffrc ;;
esac

case "$1" in
'')	maxlen=.71
	;;
C)	echo '#include "../.git-revid-autoversion.h"'
	printf 'const char autoversion[]= \"'
	log="${log//\\/\\\\}"
	log="${log//\"/\\\"}"
	maxlen=''
	;;
*)	echo >&2 'bad usage for .git-revid'
	exit 1
	;;
esac

printf "%${maxlen}s" "$log $desc$diffplus $date"

case "$kind" in
'')	printf '\n' ;;
C)	echo '";' ;;
*)	;;
esac