require "work_day"

module ROI
  module RentabilityPeriods
    def days(days_amount = 1)
      scoped_start = WorkDay.last_until(end_date - days_amount)
      format(scoped_start, end_date)
    end

    def current_month
      scoped_start = WorkDay.last_until((end_date - 1.month).end_of_month)
      check_gaps_and_format(adjust_start_date(scoped_start), end_date)
    end

    def months(amount, date = end_date)
      return current_month if amount == 1 && date == end_date

      scoped_start = WorkDay.last_until((date - (amount+1).month).end_of_month)
      scoped_end = adjust_end_date((date - 1.month).end_of_month)
      check_gaps_and_format(scoped_start, scoped_end)
    end

    def current_year
      scoped_start = WorkDay.last_until((end_date - 1.year).end_of_year)
      format(adjust_start_date(scoped_start), end_date)
    end

    def years_ago(amount)
      scoped_end = WorkDay.last_until((end_date - amount.year).end_of_year)
      scoped_start = WorkDay.last_until((scoped_end - 1.year).end_of_year)
      format(adjust_start_date(scoped_start), scoped_end)
    end

    def portfolio
      format(start_date, end_date)
    end

    private
    def adjust_start_date(date)
      [start_date, date].compact.max
    end

    def adjust_end_date(date)
      WorkDay.last_until(date.strftime("%Y-%m") == end_date.strftime("%Y-%m") ?
        end_date : date.end_of_month)
    end

    def format(start_date, end_date)
      scoped_start, scoped_end = rentabilities.values_at(start_date, end_date)
      if scoped_start && scoped_end
        ((scoped_end.share / scoped_start.share - 1) * 100).round(8)
      end
    end

    def check_gaps_and_format(scoped_start, scoped_end)
      _start, _end = rentabilities.values_at(scoped_start, scoped_end)
      return unless _start && _end
      if skip_on_gap
        rentabilities.each_value do |line|
          return if line.date.between?(_start.date, _end.date) &&
            !line.have_position
        end
      end
      format(scoped_start, scoped_end)
    end
  end
end