recurring_movement.rb

module MRR::Datapoint
  # This class generates the `recurring_movement` object for an MRR datapoint.
  class RecurringMovement
    def initialize(datapoint, previous_datapoint)
      @datapoint = datapoint
      @previous_datapoint = previous_datapoint
    end

    def build
      {
        category: category,
        amount: amount,
        description: description
      }
    end

    private

    def category
      if %w(new_business churn reactivation).include?(datapoint.mrr_movement.category)
        return datapoint.mrr_movement.category
      end

      if amount.positive?
        "expansion"
      elsif amount.negative?
        "contraction"
      else
        "no_movement"
      end
    end

    def amount
      previous_movement_amount - current_subscription_items_mrr
    end

    def description
      # CAN I PASS SUBSCRIPTION ITEMS TO CMOELS ACTIVITY GENERATOR RIGHT HERE???!!!
    end

    def previous_movement_amount
      previous_datapoint.recurring_movement.amount
    end

    def subscription_items
      datapoint.subscription.items.select(&:recurring?)
    end

    def current_subscription_items_mrr
      subscription_items.sum { |item| item.mrr_movements.sum { |movement| movement["amount"] } }
    end
  end
end