decompose_conditional.rb

# NOTE: line 7 fixes bug in original version
class TimeSetter
  ORIGIN_YEAR = 1980
  def self.calculate_current_year(days_since_origin)
    @@year = ORIGIN_YEAR
    @@days_remaining = days_since_origin
    while (@@days_remaining > 365) do
      if leap_year?
        peel_off_leap_year!
      else
        peel_off_regular_year!
      end
    end
    return @@year
  end
  private
  def peel_off_leap_year!
    if (@@days_remaining >= 366)
      @@days_remaining -= 366 ; @@year += 1
    end
  end
  def peel_off_regular_year!
    @@days_remaining -= 365 ; @@year += 1
  end
  def self.leap_year?
    @@year % 400 == 0 ||
      (@@year % 4 == 0 && @@year % 100 != 0)
  end
end