module BSON::Time

def _bson_to_i
  # Workaround for JRuby's #to_i rounding negative timestamps up
  # rather than down (https://github.com/jruby/jruby/issues/6104)
  if BSON::Environment.jruby?
    (self - usec.to_r/1000000).to_i
  else
    to_i
  end
end

def as_extended_json(**options)
  utc_time = utc
  if options[:mode] == :relaxed && (1970..9999).include?(utc_time.year)
    if utc_time.usec != 0
      if utc_time.respond_to?(:floor)
        # Ruby 2.7+
        utc_time = utc_time.floor(3)
      else
        utc_time -= utc_time.usec.divmod(1000).last.to_r / 1000000
      end
      {'$date' => utc_time.strftime('%Y-%m-%dT%H:%M:%S.%LZ')}
    else
      {'$date' => utc_time.strftime('%Y-%m-%dT%H:%M:%SZ')}
    end
  else
    sec = utc_time._bson_to_i
    msec = utc_time.usec.divmod(1000).first
    {'$date' => {'$numberLong' => (sec * 1000 + msec).to_s}}
  end
end

def to_bson(buffer = ByteBuffer.new)
  value = _bson_to_i * 1000 + usec.divmod(1000).first
  buffer.put_int64(value)
end