ama-team / cookbook-linux-user-management

require 'set'

require_relative '../model/policy'

module AMA

  module Chef

    module User

      module State

        # Simple class that builds target state by applying partitions to

        # clients

        class Builder

          # @param [Hash{Symbol, AMA::Chef::User::Model::Client}] clients

          # @param [Hash{Symbol, AMA::Chef::User::Model::Partition}] partitions

          # @return [AMA::Chef::User::Model::State]

          def build(clients, partitions)

            state = Model::State.new

            partitions.values.each do |partition|

              process_partition(state, partition, clients)

            end

            clean_state(state)

            state

          end

          private

          # @param [AMA::Chef::User::Model::State] state

          # @param [AMA::Chef::User::Model::Partition] partition

          # @param [Hash<Symbol, AMA::Chef::User::Model::Client>] clients

          def process_partition(state, partition, clients)

            unless partition.policy.group == Model::Policy::NONE

              state.groups[partition.id] = extract_group(partition)

            end

            clients.values.each do |client|

              next unless partition.applies_to(client)

              apply_partition(state, client, partition)

            end

          end

          # @param [AMA::Chef::User::Model::State] state

          # @param [AMA::Chef::User::Model::Client] client

          # @param [AMA::Chef::User::Model::Partition] partition

          def apply_partition(state, client, partition)

            account = extract_account(client, partition)

            state.account!(client.id).merge(account)

            apply_impersonation(state, client, partition)

            return unless partition.policy.group != Model::Policy::NONE

            state.group(partition.id).members.add(account.id)

          end

          # @param [AMA::Chef::User::Model::State] state

          def clean_state(state)

            state.accounts.reject! do |_, account|

              account.policy == Model::Policy::NONE

            end

            state.groups.reject! do |_, group|

              group.policy == Model::Policy::NONE

            end

            state

          end

          def extract_group(partition)

            group = Model::Group.new(partition.id)

            group.policy = partition.policy.group

            group.privileges = partition.privileges.clone

            group

          end

          # rubocop:disable Metrics/AbcSize

          def apply_impersonation(state, client, partition)

            return if client.public_keys.empty?

            partition.impersonation.keys.each do |hijacked|

              package = Model::Account.new(hijacked)

              package.policy = :edit

              package.public_keys!(client.id).merge!(client.public_keys)

              state.account!(hijacked).merge(package)

            end

          end

        end

      end

    end

  end

end