#! /bin/sh

set -e
tarball=${1?tarball}
case $tarball in /*);; *) tarball=`pwd`/$tarball;; esac
tmp=${TMPDIR-/tmp}/mup-$$
mkdir $tmp
: ${GIT_DIR=`git rev-parse --git-dir`}
case $GIT_DIR in /*);; *) GIT_DIR=`pwd`/$GIT_DIR;; esac
export GIT_DIR
trap 'cd /; rm -rf $tmp' 0
cd $tmp
GIT_INDEX_FILE=$tmp/index
export GIT_INDEX_FILE

mkdir unpack; cd unpack
cp $tarball .
tar xfz $tarball
mupdir=`ls -d mup-*`
version=${mupdir#mup-}
mv $mupdir mup
echo $version

find . -type f -print0 | git update-index --add -z --stdin
tree=$(git write-tree)
if [ -f $GIT_DIR/refs/heads/arkkra ]; then
  pp="-p $(cat $GIT_DIR/refs/heads/arkkra)"
else
  pp=""
fi
commit=$(
  echo "Import upstream version $version." |
  git commit-tree $tree $pp
)
git update-ref refs/heads/arkkra $commit
git update-ref refs/tags/$version $commit
echo "Imported Mup $version: $commit"