private const val INITIAL_BIAS = 72
  private const val INITIAL_N = 0x80

  /**
   * Returns null if any label is oversized so much that the encoder cannot encode it without
   * integer overflow. This will not return null for labels that fit within the DNS size
   * limits.
   */
  fun encode(string: String): String? {
    var pos = 0
    val limit = string.length
    val result = Buffer()

    while (pos < limit) {