class Holidays::DateCalculator::Easter::Julian

def calculate_easter_for(year)
  g = year % 19 + 1
  s = (year - 1600) / 100 - (year - 1600) / 400
  l = (((year - 1400) / 100) * 8) / 25
  p_2 = (3 - 11 * g + s - l) % 30
  if p_2 == 29 || (p_2 == 28 && g > 11)
    p = p_2 - 1
  else
    p = p_2
  end
  d= (year + year / 4 - year / 100 + year / 400) % 7
  d_2 = (8 - d) % 7
  p_3 = (80 + p) % 7
  x_2 = d_2 - p_3
  x = (x_2 - 1) % 7 + 1
  e = p+x
  if e < 11
    Date.civil(year,3,e + 21)
  else
    Date.civil(year,4,e - 10)
  end
end

def calculate_orthodox_easter_for(year)
  y = year
  g = y % 19
  i = (19 * g + 15) % 30
  j = (year + year/4 + i) % 7
  j_month = 3 + (i - j + 40) / 44
  j_day = i - j + 28 - 31 * (j_month / 4)
  Date.civil(year, j_month, j_day)
end