/**
   * Copies the properties of a specific <tt>DatagramPacket</tt> to another <tt>DatagramPacket</tt>.
   * The property values are not cloned.
   *
   * @param src the <tt>DatagramPacket</tt> which is to have its properties copied to <tt>dest</tt>
   * @param dest the <tt>DatagramPacket</tt> which is to have its properties set to the value of the
   *     respective properties of <tt>src</tt>
   */
  public static void copy(DatagramPacket src, DatagramPacket dest) {
    synchronized (dest) {
      dest.setAddress(src.getAddress());
      dest.setPort(src.getPort());

      byte[] srcData = src.getData();

      if (srcData == null) dest.setLength(0);
      else {
        byte[] destData = dest.getData();

        if (destData == null) dest.setLength(0);
        else {
          int destOffset = dest.getOffset();
          int destLength = destData.length - destOffset;
          int srcLength = src.getLength();

          if (destLength >= srcLength) destLength = srcLength;
          else if (logger.isLoggable(Level.WARNING)) {
            logger.log(Level.WARNING, "Truncating received DatagramPacket data!");
          }
          System.arraycopy(srcData, src.getOffset(), destData, destOffset, destLength);
          dest.setLength(destLength);
        }
      }
    }
  }
  /**
   * Initializes a new <tt>DatagramPacket</tt> instance which is a clone of a specific
   * <tt>DatagramPacket</tt> i.e. the properties of the clone <tt>DatagramPacket</tt> are clones of
   * the specified <tt>DatagramPacket</tt>.
   *
   * @param p the <tt>DatagramPacket</tt> to clone
   * @return a new <tt>DatagramPacket</tt> instance which is a clone of the specified
   *     <tt>DatagramPacket</tt>
   */
  public static DatagramPacket clone(DatagramPacket p) {
    synchronized (p) {
      byte[] pData = p.getData();
      byte[] cData = (pData == null) ? null : pData.clone();

      return new DatagramPacket(cData, p.getOffset(), p.getLength(), p.getAddress(), p.getPort());
    }
  }
  /**
   * Creates a new <tt>RawPacket</tt> from a specific <tt>DatagramPacket</tt> in order to have this
   * instance receive its packet data through its {@link #read(byte[], int, int)} method. Returns an
   * array of <tt>RawPacket</tt> with the created packet as its first element (and <tt>null</tt> for
   * the other elements).
   *
   * <p>Allows extenders to intercept the packet data and possibly filter and/or modify it.
   *
   * @param datagramPacket the <tt>DatagramPacket</tt> containing the packet data
   * @return an array of <tt>RawPacket</tt> containing the <tt>RawPacket</tt> which contains the
   *     packet data of the specified <tt>DatagramPacket</tt> as its first element.
   */
  protected RawPacket[] createRawPacket(DatagramPacket datagramPacket) {
    RawPacket[] pkts = rawPacketArrayPool.poll();
    if (pkts == null) pkts = new RawPacket[1];

    RawPacket pkt = rawPacketPool.poll();
    if (pkt == null) pkt = new RawPacket();

    pkt.setBuffer(datagramPacket.getData());
    pkt.setFlags(0);
    pkt.setLength(datagramPacket.getLength());
    pkt.setOffset(datagramPacket.getOffset());

    pkts[0] = pkt;
    return pkts;
  }
  private void runOnDtlsTransport(StreamConnector connector) throws IOException {
    DtlsControlImpl dtlsControl = (DtlsControlImpl) getTransportManager().getDtlsControl(this);
    DtlsTransformEngine engine = dtlsControl.getTransformEngine();
    final DtlsPacketTransformer transformer = (DtlsPacketTransformer) engine.getRTPTransformer();

    byte[] receiveBuffer = new byte[SCTP_BUFFER_SIZE];

    if (LOG_SCTP_PACKETS) {
      System.setProperty(
          ConfigurationService.PNAME_SC_HOME_DIR_LOCATION, System.getProperty("java.io.tmpdir"));
      System.setProperty(
          ConfigurationService.PNAME_SC_HOME_DIR_NAME, SctpConnection.class.getName());
    }

    synchronized (this) {
      // FIXME local SCTP port is hardcoded in bridge offer SDP (Jitsi
      // Meet)
      sctpSocket = Sctp.createSocket(5000);
      assocIsUp = false;
      acceptedIncomingConnection = false;
    }

    // Implement output network link for SCTP stack on DTLS transport
    sctpSocket.setLink(
        new NetworkLink() {
          @Override
          public void onConnOut(SctpSocket s, byte[] packet) throws IOException {
            if (LOG_SCTP_PACKETS) {
              LibJitsi.getPacketLoggingService()
                  .logPacket(
                      PacketLoggingService.ProtocolName.ICE4J,
                      new byte[] {0, 0, 0, (byte) debugId},
                      5000,
                      new byte[] {0, 0, 0, (byte) (debugId + 1)},
                      remoteSctpPort,
                      PacketLoggingService.TransportName.UDP,
                      true,
                      packet);
            }

            // Send through DTLS transport
            transformer.sendApplicationData(packet, 0, packet.length);
          }
        });

    if (logger.isDebugEnabled()) {
      logger.debug("Connecting SCTP to port: " + remoteSctpPort + " to " + getEndpoint().getID());
    }

    sctpSocket.setNotificationListener(this);
    sctpSocket.listen();

    // FIXME manage threads
    threadPool.execute(
        new Runnable() {
          @Override
          public void run() {
            SctpSocket sctpSocket = null;
            try {
              // sctpSocket is set to null on close
              sctpSocket = SctpConnection.this.sctpSocket;
              while (sctpSocket != null) {
                if (sctpSocket.accept()) {
                  acceptedIncomingConnection = true;
                  break;
                }
                Thread.sleep(100);
                sctpSocket = SctpConnection.this.sctpSocket;
              }
              if (isReady()) {
                notifySctpConnectionReady();
              }
            } catch (Exception e) {
              logger.error("Error accepting SCTP connection", e);
            }

            if (sctpSocket == null && logger.isInfoEnabled()) {
              logger.info(
                  "SctpConnection " + getID() + " closed" + " before SctpSocket accept()-ed.");
            }
          }
        });

    // Notify that from now on SCTP connection is considered functional
    sctpSocket.setDataCallback(this);

    // Setup iceSocket
    DatagramSocket datagramSocket = connector.getDataSocket();
    if (datagramSocket != null) {
      this.iceSocket = new IceUdpSocketWrapper(datagramSocket);
    } else {
      this.iceSocket = new IceTcpSocketWrapper(connector.getDataTCPSocket());
    }

    DatagramPacket rcvPacket = new DatagramPacket(receiveBuffer, 0, receiveBuffer.length);

    // Receive loop, breaks when SCTP socket is closed
    try {
      do {
        iceSocket.receive(rcvPacket);

        RawPacket raw =
            new RawPacket(rcvPacket.getData(), rcvPacket.getOffset(), rcvPacket.getLength());

        raw = transformer.reverseTransform(raw);
        // Check for app data
        if (raw == null) continue;

        if (LOG_SCTP_PACKETS) {
          LibJitsi.getPacketLoggingService()
              .logPacket(
                  PacketLoggingService.ProtocolName.ICE4J,
                  new byte[] {0, 0, 0, (byte) (debugId + 1)},
                  remoteSctpPort,
                  new byte[] {0, 0, 0, (byte) debugId},
                  5000,
                  PacketLoggingService.TransportName.UDP,
                  false,
                  raw.getBuffer(),
                  raw.getOffset(),
                  raw.getLength());
        }

        // Pass network packet to SCTP stack
        sctpSocket.onConnIn(raw.getBuffer(), raw.getOffset(), raw.getLength());
      } while (true);
    } finally {
      // Eventually, close the socket although it should happen from
      // expire().
      synchronized (this) {
        assocIsUp = false;
        acceptedIncomingConnection = false;
        if (sctpSocket != null) {
          sctpSocket.close();
          sctpSocket = null;
        }
      }
    }
  }