#!/bin/sh
set -eu

if [ "$#" -ne 1 ]; then
  echo "usage: $0 CHART" >&2
  exit 2
fi
chart=$1
description=$(git describe --tags --long --match "${chart}-v[0-9]*" --dirty)
case "$description" in
  *-dirty) echo "refusing to package a dirty tree" >&2; exit 1 ;;
esac
version=${description#${chart}-v}
case "$version" in
  *-0-g*) version=${version%%-0-g*} ;;
esac
printf '%s\n' "$version"