response_enumerator.rb

class ResponseEnumerator < Enumerator
  DEFAULT_PER_PAGE = 25

  attr_accessor :per_page

  def initialize(square, http_verb:, path:, data:,
                 fields:, parameters: {}, memoize: true, per_page: nil)
    @per_page = per_page || DEFAULT_PER_PAGE
    @memoized_responses = []
    @params = parameters.fetch :params

    super() do |yielder|
      the_end = false

      @memoized_responses.each do |response|
        yielder << response

        the_end = true unless response.cursor
      end

      loop do
        break if the_end

        response = Response.new square, http_verb: http_verb, path: path,
                                        data: data, fields: fields, parameters: parameters
        @memoized_responses << response if memoize

        yielder << response

        cursor = response.cursor
        break unless cursor

        @params[:cursor] = cursor
      end
    end
  end

  def paginate(page:, per_page: @per_page)
    lazy.flat_map(&:to_a).drop(page.pred * per_page).first(per_page)
  end

  def clear
    @params[:cursor] = nil
    @memoized_responses.clear
    rewind
  end
  alias flush_cache clear
end