class Eco::API::UseCases::Default::People::SwitchSupervisorCase < Eco::API::Common::Loaders::UseCase
  name "switch-supervisor"
  type :transform

  def main(people, session, _options, usecase)
    supers   = session.new_job("main", "supers", :update, usecase, :core)

    old_sup, new_sup = get_supers(people).tap do |sups|
      inform(*sups)
    end

    micro.with_each_subordinate(old_sup, people) do |subordinate|
      subordinate.supervisor_id = new_sup&.id
      supers.add(subordinate)
    end.tap do |subordinates|
      next unless subordinates.empty?

      sup_str = "#{old_sup.external_id} (#{old_sup.name} - #{old_sup.email})"
      log(:error) {
        "There are no subordinates for supervisor #{sup_str}. Aborting..."
      }
      exit(1)
    end
  end

  private

  def get_supers(people)
    micro            = session.micro
    old_id,  new_id  = get_super_ids(options)
    old_sup, new_sup = [nil, nil] # rubocop:disable Style/ParallelAssignment

    micro.with_supervisor(old_id, people) do |supervisor|
      unless (old_sup = supervisor)
        log(:error) {
          "Couldn't find any user with that id (old-super): '#{old_id}'. Aborting..."
        }
        exit(1)
      end
    end

    micro.with_supervisor(new_id, people) do |supervisor|
      next if (new_sup = supervisor)

      log(:error) {
        "Couldn't find any user with that id (new-super): '#{new_id}'. Aborting..."
      }
      exit(1)
    end

    [old_sup, new_sup]
  end

  def get_super_ids(options)
    unless (old_id = options.dig(:super, :old))
      log(:error) { "You haven't specified the original supervisor. Aborting..." }
      exit(1)
    end

    # we could be setting the supervisor to nil
    unless options[:super].key?(:new)
      log(:error) { "You haven't specified the new supervisor. Aborting..." }
      exit(1)
    end

    [old_id, options.dig(:super, :new)]
  end

  def inform(old_sup, new_sup)
    msg  = "Switching supervisor '#{old_sup.name}' (#{old_sup.external_id}) "
    msg += "to '#{new_sup&.name}' (#{new_sup&.external_id})"
    log(:info) { msg }
  end
end