#!/bin/bash

# Fail on any error.
set -e

# Directory that holds the cached packages.
cache_dir=$1

# Root directory to untar the cached packages to.
# Typically filesystem root '/' but can be changed for testing.
cache_restore_root=$2

# List of the packages to use.
packages="${@:3}"

# Only search for archived results. Manifest and cache key also live here.
cache_filenames=$(ls -1 $cache_dir | grep .tar.gz | sort)
cache_filename_count=$(echo $cache_filenames | wc -w)

echo -n "Restoring $cache_filename_count packages from cache..."
for cache_filename in $cache_filenames; do
  cache_filepath=$cache_dir/$package.tar.gz
  echo "- $package ($cache_filepath)"
  sudo tar -xf $cache_filepath -C $cache_restore_root > /dev/null
done
echo "done."