sul-dlss/dor-services-app

# frozen_string_literal: true

# Finds the members of a collection
class MemberService
  # @param [String] druid the identifier of the collection
  # @param [Boolean] publishable when true, restrict to publishable items only
  # @return [Array<String>] the druids for the members of this collection
  def self.for(druid, publishable: false)
    new(druid, publishable:).for
  end

  def initialize(druid, publishable: false)
    @druid = druid
    @publishable = publishable
  end

  def for
    RepositoryObject
      .currently_members_of_collection(druid)
      .select(:external_identifier, :version, :head_version_id, :opened_version_id, :last_closed_version_id)
      .then { |members| publishable_members(members) }
      .map(&:external_identifier)
  end

  private

  attr_reader :druid, :publishable

  def publishable_members(members)
    return members unless publishable

    members.select(&:publishable?)
  end
end