# frozen_string_literal: true

module Reports::DauByMau
  extend ActiveSupport::Concern

  class_methods do
    def report_dau_by_mau(report)
      report.labels = [
        {
          type: :date,
          property: :x,
          title: I18n.t("reports.default.labels.day")
        },
        {
          type: :percent,
          property: :y,
          title: I18n.t("reports.default.labels.percent")
        },
      ]

      report.average = true
      report.percent = true

      data_points = UserVisit.count_by_active_users(report.start_date, report.end_date)

      report.data = []

      compute_dau_by_mau = Proc.new { |data_point|
        if data_point["mau"] == 0
          0
        else
          ((data_point["dau"].to_f / data_point["mau"].to_f) * 100).ceil(2)
        end
      }

      dau_avg = Proc.new { |start_date, end_date|
        data_points = UserVisit.count_by_active_users(start_date, end_date)
        if !data_points.empty?
          sum = data_points.sum { |data_point| compute_dau_by_mau.call(data_point) }
          (sum.to_f / data_points.count.to_f).ceil(2)
        end
      }

      data_points.each do |data_point|
        report.data << { x: data_point["date"], y: compute_dau_by_mau.call(data_point) }
      end

      if report.facets.include?(:prev_period)
        report.prev_period = dau_avg.call(report.prev_start_date, report.prev_end_date)
      end

      if report.facets.include?(:prev30Days)
        report.prev30Days = dau_avg.call(report.start_date - 30.days, report.start_date)
      end
    end
  end
end