class ActiveFedora::WithMetadata::MetadataNode

def create_delegating_setter(name)
  file.class.delegate(name, to: :metadata_node)
end

def exec_block(&block)
  class_eval &block
end

def initialize(file)
  @file = file
  super(file.uri, ldp_source.graph)
end

def ldp_connection
  ActiveFedora.fedora.connection
end

def ldp_source
  @ldp_source ||= LdpResource.new(ldp_connection, metadata_uri)
end

def metadata_uri
  @metadata_uri ||= if file.new_record?
    ::RDF::URI.new nil
  else
    raise "#{file} must respond_to described_by" unless file.respond_to? :described_by
    file.described_by
  end
end

def metadata_uri= uri
  @metadata_uri = uri
end

def parent_class
  @parent_class
end

def parent_class= parent
  @parent_class = parent
end

def property(name, options)
  parent_class.delegate name, :"#{name}=", :"#{name}_changed?", to: :metadata_node
  super
end

def save
  raise "Save the file first" if file.new_record?
  change_set = ChangeSet.new(self, self, changed_attributes.keys)
  SparqlInsert.new(change_set.changes, ::RDF::URI.new(file.uri)).execute(metadata_uri)
  @ldp_source = nil
  true
end

def set_value(*args)
  super
  attribute_will_change! args.first
end