Calculating PTO with PTO Class

pto.rb

class Pto
  attr_accessor :hire_date, :hire_date_vacation_adjustment, :vacation_this_year, :ytd, :eoy_accrual

  def initialize(hire_date, hire_date_vacation_adjustment, vacation_this_year)
    self.hire_date = hire_date
    self.hire_date_vacation_adjustment = hire_date_vacation_adjustment
    self.vacation_this_year = vacation_this_year
    calculate_pto
  end

  #first_of_year = Time.local(DateTime.now.year, 1)
  def calculate_pto
    #Subtract one for January and add a pay period if the middle of the month has gone by
    ytd_pay_periods = ((DateTime.now.month - 1) * 2) + (DateTime.now.day > 16 ? 1 : 0)

    start_date = self.hire_date_vacation_adjustment.nil? ? self.hire_date.to_datetime : self.hire_date_vacation_adjustment.to_datetime
    years_worked = actual_years_worked(start_date)
    rate = get_rate(years_worked)
    self.ytd = (ytd_pay_periods * get_rate(years_worked) ) - self.vacation_this_year.to_f
    #puts "Rate: " + rate.inspect

    self.eoy_accrual = calculate_year_accrual(years_worked, start_date, rate)
  end

  #Calculate Full Year Accrual
  def calculate_year_accrual(years_worked, start_date, rate)
    pay_periods = 24 #standard pay periods
    first_of_year = DateTime.new(DateTime.now.year, 1, 1)
    end_of_year = DateTime.new(DateTime.now.year, 12, 31)
    how_many_years = ((end_of_year - start_date)/365.25).to_i
    #puts "Rate: " + rate.inspect
    eoy_rate = get_rate(how_many_years)
    #puts "EOY Rate: " + eoy_rate.inspect
    return ( (pay_periods * rate) - self.vacation_this_year.to_f) if eoy_rate == rate
    #Split Year, calculate up til anniversary accrual and after anniversary accrual
    anniversary = DateTime.new(DateTime.now.year, start_date.month, start_date.day)

    #pay periods until anniversary * rate + after anniversary * eoy_rate
    up_to_anni_pp = ( ( (anniversary.month - 1 ) * 2 ).to_i)  + (anniversary.day > 16 ? 1 : 0)
    after_anni_pp = ( ( (end_of_year.month - anniversary.month) ).to_i + 1 ) * 2 - (anniversary.day > 16 ? 1 : 0)
    return (up_to_anni_pp * rate) + (after_anni_pp * eoy_rate) - self.vacation_this_year.to_f
  end

  def calculate_sick_time
    #first_of_year = Time.local(DateTime.now.year, 1)
    #adj_pay_periods = DateTime.now.day > 16 ? 1 : 0
    return "coming soon"
  end

  private
  def actual_years_worked(start_date)
    now = Time.now.utc.to_date
    now.year - start_date.year - ((now.month > start_date.month || (now.month == start_date.month && now.day >= start_date.day)) ? 0 : 1)
  end

  def get_rate(years_worked)
    rates = [Settings.pto_accum_rate, Settings.pto_accum_rate_2_yr, Settings.pto_accum_rate_4_yr, Settings.pto_accum_rate_6_yr, Settings.pto_accum_rate_8_yr]

   case
    when years_worked >= 8
      return rates[4]
    when years_worked >= 6
      return rates[3]
    when years_worked >= 4
      return rates[2]
    when years_worked >= 2
      return rates[1]
    else
      return rates[0]
    end

  end
end