class Object

# File lib/s3ff.rb, line 11
def s3_file_field_with_s3ff(method, options = {})
  direct_url_attr = "#{method}_direct_url"
  changes = @object.try(:changes) || {} # { attr => [old_value, new_value], ... }
  new_direct_url = (@object.class.column_names.include?(direct_url_attr) ?
    changes[direct_url_attr].try(:last) :
    @object.try(direct_url_attr))
  # set new_direct_url if such a db attribute exist & it has changed
  # but if it isn't a db attribute, try and use attr_reader
  if new_direct_url.present?
    # this means we're re-rendering :. we should prepopulate the s3ff fields to avoid re-uploading
    options[:data] ||= {}
    options[:data][:s3ff] ||= begin
      [*new_direct_url].collect do |url|
        {
          fieldname: "#{object_name.to_s}[#{direct_url_attr}]#{options[:multiple] ? '[]' : ''}",
          unique_id: "#{object_name.to_s.parameterize}#{SecureRandom.hex}",
          result: {
            filename: File.basename(url),
            url: url,
          },
        }
      end
    end
  end
  s3_file_field_without_s3ff(method, options)
end