4-4-5 support?

[yoelblum]

Hello,
I am using the gem and may have the requirement to support 4-4-5 calendar. Is it possible to do with little monkey patching or is it big changes and I'll have to look at some other solutions?
I thought perhaps changing these constants could do the trick or is it not that simple?

  class RetailCalendar
    LAST_MONTH_OF_THE_YEAR = "January"
    LAST_DAY_OF_THE_YEAR = 31

    QUARTER_1 = 1
    QUARTER_2 = 2
    QUARTER_3 = 3
    QUARTER_4 = 4
    
    FOUR_WEEK_MONTHS = [2, 5, 8, 11]
    FIVE_WEEK_MONTHS = [3, 6, 9, 12]

[yoelblum]

If anyone still looking for a solution for this, I made a gem https://github.com/yoelblum/retail_calendar/

[foxhard]

@yoelblum, I think you can do the trick by overriding the start_of_month method of RetailCalendar class. Something like this:

class Calendar445 < MerchCalendar::RetailCalendar
  FOUR_WEEK_MONTHS = [2, 5, 8, 11].freeze
  FIVE_WEEK_MONTHS = [3, 6, 9, 12].freeze

  def start_of_month(year, merch_month)
    # 91 = number of days in a single 4-4-5 set
    # Merch months
    # ============
    # row 1 (4 weeks): feb(1) may(4) aug(7) nov(10)
    # row 2 (4 weeks): mar(2) jun(5) sep(8) dec(11)
    # row 3 (5 weeks): apr(3) jul(6) oct(9) jan(12)

    # This line will get the start of the month for any of the merch months in row 1
    start = start_of_year(year) + ((merch_month - 1) / 3).to_i * 91

    # This code will get the start of the month of any of the merch months in row 2 or row 3
    case merch_month
    when *FOUR_WEEK_MONTHS
      # 28 = 4 weeks
      start += 28
    when *FIVE_WEEK_MONTHS
      # 56 = 8 weeks
      start += 56
    end

    start
  end
end

So you can use it as this:

merch_week = MerchCalendar::MerchWeek.from_date('2022-01-25', calendar: Calendar445.new)
puts merch_week.start_of_month # 2021-12-26

If you need to get the start or end date of the quarter, you can monkey patching the MerchWeek class like this:

 module MerchCalendar
  class MerchWeek
    def end_of_quarter
      calendar.end_of_quarter(year, quarter)
    end

    def start_of_quarter
      calendar.start_of_quarter(year, quarter)
    end
  end
end

So you can use the stuff like this:

merch_week = MerchCalendar::MerchWeek.from_date('2022-01-25', calendar: Calendar445.new)

puts merch_week.start_of_quarter # 2021-10-31
puts merch_week.end_of_quarter  # 2022-01-29