module Dor
  module Embargoable
    extend ActiveSupport::Concern
    include Dor::Publishable

    included do
      has_metadata :name => 'embargoMetadata', :type => Dor::EmbargoMetadataDS, :label => 'Embargo metadata'
    end

    # These methods manipulate the object for embargo purposes
    # They assume the object has embargoMetadata, rightsMetadata, and events datastreams

    # Manipulates datastreams in the object when embargo is lifted:
    # Sets embargo status to released in embargoMetadata
    # Modifies rightsMetadata to remove embargoReleaseDate and updates/adds access from embargoMetadata/releaseAccess
    # @param [String] release_agent name of the person, application or thing that released embargo
    # @note The caller should save the object to fedora to commit the changes
    def release_embargo(release_agent="unknown")
      # Set status to released
      embargo_md = datastreams['embargoMetadata']
      embargo_md.status = 'released'

      # Remove all read acces nodes
      rights_xml = datastreams['rightsMetadata'].ng_xml
      rights_xml.xpath("//rightsMetadata/access[@type='read']").each { |n| n.remove }

      # Replace rights <access> nodes with those from embargoMetadta
      release_access = embargo_md.release_access_node
      release_access.xpath('//releaseAccess/access').each do |new_access|
        access_sibling = rights_xml.at_xpath("//rightsMetadata/access[last()]")
        if(access_sibling)
          access_sibling.add_next_sibling(new_access.clone)
        else
          rights_xml.root.add_child(new_access.clone)
        end
      end

      datastreams['rightsMetadata'].content_will_change!
      datastreams['events'].add_event("embargo", release_agent, "Embargo released")
    end

    def world_doc
      builder = Nokogiri::XML::Builder.new do |xml|
        xml.access(:type => 'read') {
          xml.machine {
            xml.world
          }
        }
      end
      return builder.doc
    end

    def release_20_pct_vis_embargo(release_agent="unknown")
      # Set status to released
      embargo_md = datastreams['embargoMetadata']
      embargo_md.twenty_pct_status = 'released'

      # Remove all read acces nodes
      rights_xml = datastreams['rightsMetadata'].ng_xml
      rights_xml.xpath("//rightsMetadata/access[@type='read']").each { |n| n.remove }

      # Replace rights <access> nodes with 1 machine/world node
      access_sibling = rights_xml.at_xpath("//rightsMetadata/access[last()]")
      if(access_sibling)
        access_sibling.add_next_sibling(world_doc.root.clone)
      else
        rights_xml.root.add_child(world_doc.root.clone)
      end

      datastreams['rightsMetadata'].content_will_change!
      datastreams['events'].add_event("embargo", release_agent, "20% Visibility Embargo released")
    end

    def update_embargo(new_date)
      if embargoMetadata.status != 'embargoed'
        raise ArgumentError, 'You cannot change the embargo date of an item thant isnt embargoed.'
      end
      if new_date.past?
        raise ArgumentError, 'You cannot set the embargo date to a past date.'
      end
      updated=false
      self.rightsMetadata.ng_xml.search('//embargoReleaseDate').each do |node|
        node.content=new_date.beginning_of_day.utc.xmlschema
        updated=true
      end
      self.rightsMetadata.content=self.rightsMetadata.ng_xml.to_s
      self.rightsMetadata.save
      raise 'No release date in rights metadata, cannot proceed!' unless updated
      self.embargoMetadata.ng_xml.xpath('//releaseDate').each do |node|
        node.content=new_date.beginning_of_day.utc.xmlschema
      end
      self.embargoMetadata.content=self.embargoMetadata.ng_xml.to_s
      self.embargoMetadata.save
    end
  end
end