class ReeDao::PersistAssoc

def call(agg_root, assoc_dao, **opts)
  setter_method = if opts[:root_setter].nil?
    name = underscore(demodulize(agg_root.class.name))
    "#{name}_id="
  else
    "#{opts[:root_setter]}"
  end
  assoc_name = if opts[:child_assoc].nil?
    dto_class = assoc_dao
      .opts[:schema_mapper]
      .dto(:db_load)
    name = underscore(demodulize(dto_class.name))
    "#{name}s"
  else
    opts[:child_assoc]
  end
  agg_root.send(assoc_name).each do |child|
    if !child.respond_to?(setter_method)
      raise ArgumentError.new("#{child.class} does not respond to `#{setter_method}` method")
    end
    child.send(setter_method, agg_root.id)
    if child.id
      assoc_dao.update(child)
    else
      assoc_dao.put(child)
    end
  end
  nil
end