module CopticDate

# File lib/coptic_date.rb, line 5
def self.calculate_remainder(greg_date)
  # this may look wierd, however this is how calculations are made
  greg_date_day = greg_date.day
  greg_date_month = greg_date.month
  greg_date_year = greg_date.year

  if greg_date_month <= 2
    intA = greg_date_month + 12
    intB = greg_date_year - 1
  else
    intA = greg_date_month
    intB = greg_date_year
  end

  intC = (intB / 100).to_i
  intD = (intB / 400).to_i
  intE = 2 - intC + intD
  intF = ((intB + 4716) * 36525 / 100).to_i
  intG = ((intA + 1) * 306001 / 10000).to_i
  base_date = (greg_date_day + intG + intF + intE - 1826553)
  c_year = base_date.div 365.25
  #puts "base_date #{base_date}"
  return ((base_date % 365.25) / 365.25) * 12.175
end

# File lib/coptic_date.rb, line 56
def self.get_coptic_day(greg_date)
  c_year = get_coptic_year(greg_date)
  if c_year % 4 == 3 && greg_date.year % 4 == 3 && greg_date.month == 9 && greg_date.day == 11
    return 6
  else
    remainder = calculate_remainder(greg_date)
    #puts remainder
    cday = (("0." + remainder.to_s.split(".")[1]).to_f * 30).round
    cday < 1? 1 : cday
  end
end

# File lib/coptic_date.rb, line 47
def self.get_coptic_month(greg_date)
  c_year = get_coptic_year(greg_date)
  if c_year % 4 == 3 && greg_date.year % 4 == 3 && greg_date.month == 9 && greg_date.day == 11
    return 13
  else
    calculate_remainder(greg_date).to_i + 1
  end
end

# File lib/coptic_date.rb, line 68
def self.get_coptic_month_name(month_number)
  case month_number
  when 1
    "توت"
  when 2
    "بابه"
  when 3
    "هاتور"
  when 4
    "كيهك"
  when 5
    "طوبه"
  when 6
    "أمشير"
  when 7
    "برمهات"
  when 8
    "برموده"
  when 9
    "بشنس"
  when 10
    "بؤنة"
  when 11
    "أبيب"
  when 12
    "مسرى"
  else
    "النسئ"
  end
end

# File lib/coptic_date.rb, line 30
def self.get_coptic_year(greg_date)
  if (greg_date.month < 9 || (greg_date.month  == 9 && greg_date.day < 11))
    return greg_date.year - 284
  elsif (greg_date.month > 9 || (greg_date.month  == 9 && greg_date.day > 11))
    return greg_date.year - 283
  else
    #This means 11 September
    #This needs calculations
    c_year = greg_date.year - 284
    if c_year % 4 == 3 && greg_date.year % 4 == 3
      return c_year
    else
      return c_year + 1
    end
  end
end