class BSON::Decimal128

def <=>(other)
  to_d <=> case other
    when Decimal128
      other.to_d
    else
      other
    end
end

def ==(other)
  return false unless other.is_a?(Decimal128)
  @high == other.instance_variable_get(:@high) &&
      @low == other.instance_variable_get(:@low)
end

def as_extended_json(**_options)
  { EXTENDED_JSON_KEY => to_s }
end

def as_json(*args)
  value = to_s
  value unless %w[NaN Infinity -Infinity].include?(value)
end

def bson_type
  BSON_TYPE
end

def from_bits(low, high)
  decimal = allocate
  decimal.send(:set_bits, low, high)
  decimal
end

def from_bson(buffer, **options)
  from_bits(*buffer.get_decimal128_bytes.unpack('Q<*'))
end

def from_string(string)
  from_bits(*Builder::FromString.new(string).bits)
end

def hash
  num = @high << 64
  num |= @low
  num.hash
end

def initialize(object)
  if object.is_a?(String)
    set_bits(*Builder::FromString.new(object).bits)
  elsif object.is_a?(BigDecimal)
    set_bits(*Builder::FromBigDecimal.new(object).bits)
  else
    raise Error::InvalidDecimal128Argument.new
  end
end

def inspect
  "BSON::Decimal128('#{to_s}')"
end

def set_bits(low, high)
  @low = low
  @high = high
end

def to_bson(buffer = ByteBuffer.new)
  buffer.put_decimal128(@low, @high)
end

def to_d
  @big_decimal ||= BigDecimal(to_s)
end

def to_s
  @string ||= Builder::ToString.new(self).string
end