module FieldTest
  module Helpers
    def field_test(experiment, **options)
      exp = FieldTest::Experiment.find(experiment)

      participants = FieldTest::Participant.standardize(options[:participant] || field_test_participant)

      if try(:request)
        options = options.dup

        if !options[:variant] && params[:field_test] && params[:field_test][experiment] && exp.variants.include?(params[:field_test][experiment])
          params_variant = params[:field_test][experiment]
        end

        if FieldTest.exclude_bots?
          options[:exclude] ||= Browser.new(request.user_agent).bot?
        end

        options[:exclude] ||= FieldTest.excluded_ips.any? { |ip| ip.include?(request.remote_ip) }

        options[:ip] = request.remote_ip
        options[:user_agent] = request.user_agent
      end

      # don't update variant when passed via params
      if params_variant
        params_variant
      else
        # cache results for request
        # TODO possibly remove in 0.4.0
        cache_key = [exp.id, participants.map(&:where_values), options.slice(:variant, :exclude)]
        @field_test_cache ||= {}
        @field_test_cache[cache_key] ||= exp.variant(participants, options)
      end
    end

    def field_test_converted(experiment, **options)
      exp = FieldTest::Experiment.find(experiment)

      participants = FieldTest::Participant.standardize(options[:participant] || field_test_participant)

      exp.convert(participants, goal: options[:goal])
    end

    # TODO fetch in single query
    def field_test_experiments(**options)
      participants = FieldTest::Participant.standardize(options[:participant] || field_test_participant)
      experiments = {}
      participants.each do |participant|
        FieldTest::Membership.where(participant.where_values).each do |membership|
          experiments[membership.experiment] ||= membership.variant
        end
      end
      experiments
    end
  end
end