#!/tools/bin/bash

NAME=$1
VERSION=$2

if [ -z $NAME ]; then
	echo "[e] Please provide a package name.">&2
	exit 1
fi
VERSIONS="/usr/dafuq/packages/$NAME-*"
if [ -z $VERSIONS ]; then
	echo "[e] Cannot find package.">&2
	exit 1
fi
echo "[i] Available versions:"
i=0
for version in $VERSIONS; do
	echo "  [$i] $version"
	i=$(expr $i + 1)
done
if [ $i == "1" ]; then
	VERSION=$VERSIONS
elif [ -z $VERSION ]; then
	echo "[e] Please provide a version number.">&2
	exit 1
else
	VERSION=$(echo $VERSIONS | cut -d" " -f $(expr $VERSION + 1))	
	if [ -z $VERSION ]; then
		echo "[e] Incorrect version number.">&2
		exit 1
	fi
fi

INSTALLED_VERSIONS=/usr/dafuq/installed/$NAME-*
if test -n "$(shopt -s nullglob; echo $INSTALLED_VERSIONS)"; then
	echo "[e] Following version(s) of package already installed:"
	for version in $INSTALLED_VERSIONS; do
		echo "  $(echo $version | sed -e "s,/usr/dafuq/installed/,,")"
	done
	exit 1
fi

echo "[i] Checking for collisions..."
MANIFEST=$(tar xfO $VERSION manifest)
while read -r line; do
	linetype=$(echo $line | cut -d":" -f 1)
	if [ $linetype == "file" ]; then
		filename=$(echo $line | cut -d" " -f 2)
		if [ -e $filename ]; then
			echo "[e] File exists in filesystem: $filename"
			exit 1
		fi
	fi
done <<< "$MANIFEST"
echo "[i] Installing..."
tar xfp $VERSION -C / --transform 's,^root/,,' --transform 's,^root,,' --show-transformed root/
ln -s $VERSION $(echo $VERSION | sed -e "s,/usr/dafuq/packages/,/usr/dafuq/installed/,")
echo "[i] Done."