apply {
        require(tls) { "no cipher suites for cleartext connections" }
        require(cipherSuites.isNotEmpty()) { "At least one cipher suite is required" }

        @Suppress("UNCHECKED_CAST")
        this.cipherSuites = cipherSuites.copyOf() as Array<String> // Defensive copy.
      }

    fun allEnabledTlsVersions() =
      apply {

      }
    }
  }
  return false
}

internal fun Array<String>.indexOf(
  value: String,
  comparator: Comparator<String>,
): Int = indexOfFirst { comparator.compare(it, value) == 0 }

@Suppress("UNCHECKED_CAST")
internal fun Array<String>.concat(value: String): Array<String> {
  val result = copyOf(size + 1)
  result[result.lastIndex] = value
  return result as Array<String>
}

import java.net.ProtocolException
import okio.ByteString

/**
 * ASN.1 adapters adapted from the specifications in [RFC 5280][rfc_5280].
 *
 * [rfc_5280]: https://tools.ietf.org/html/rfc5280
 */
@Suppress("UNCHECKED_CAST") // This needs to cast decoded collections.
internal object CertificateAdapters {
  /**
   * ```
   * Time ::= CHOICE {
   *   utcTime        UTCTime,
   *   generalTime    GeneralizedTime
   * }
   * ```

@Suppress("NOTHING_TO_INLINE")
internal inline fun <K, V> Map<K, V>.unmodifiable(): Map<K, V> = Collections.unmodifiableMap(this)

/** Returns an immutable copy of this. */
@Suppress("UNCHECKED_CAST")
internal fun <T> List<T>.toImmutableList(): List<T> =
  when {
    this.isEmpty() -> emptyList()

    this.size == 1 -> Collections.singletonList(this[0])