class Berkshelf::Installer

def install_from_universe
  Berkshelf.log.info "Installing from universe"
  dependencies = lockfile.graph.locks.values + berksfile.dependencies
  dependencies = dependencies.inject({}) do |hash, dependency|
    # Fancy way of ensuring no duplicate dependencies are used...
    hash[dependency.name] ||= dependency
    hash
  end.values
  download_locations(dependencies)
  Berkshelf.log.debug "  Creating a resolver"
  resolver = Resolver.new(berksfile, dependencies)
  # Unlike when installing from the lockfile, we _always_ need to build
  # the universe when installing from the universe... duh
  build_universe
  # Add any explicit dependencies for already-downloaded cookbooks (like
  # path locations)
  dependencies.each do |dependency|
    if dependency.location
      cookbook = dependency.cached_cookbook
      Berkshelf.log.debug "  Adding explicit dependency on #{cookbook}"
      resolver.add_explicit_dependencies(cookbook)
    end
  end
  Berkshelf.log.debug "  Starting resolution..."
  futures = resolver.resolve.sort.map { |dependency| Concurrent::Future.execute(executor: pool) { worker.install(dependency) } }
  cookbooks = futures.map(&:value)
  rejects = futures.select(&:rejected?)
  raise rejects.first.reason unless rejects.empty?
  [dependencies, cookbooks]
end