content: /**
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License.  You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.activemq.transport.mqtt;
  
  import java.io.IOException;
  import java.security.cert.X509Certificate;
  import java.util.concurrent.atomic.AtomicBoolean;
  
  import jakarta.jms.JMSException;
  
  import org.apache.activemq.broker.BrokerService;
  import org.apache.activemq.command.Command;
  import org.apache.activemq.transport.Transport;
  import org.apache.activemq.transport.TransportFilter;
  import org.apache.activemq.transport.TransportListener;
  import org.apache.activemq.transport.nio.NIOSSLTransport;
  import org.apache.activemq.transport.tcp.SslTransport;
  import org.apache.activemq.util.IOExceptionSupport;
  import org.apache.activemq.wireformat.WireFormat;
  import org.fusesource.mqtt.codec.CONNACK;
  import org.fusesource.mqtt.codec.CONNECT;
  import org.fusesource.mqtt.codec.DISCONNECT;
  import org.fusesource.mqtt.codec.MQTTFrame;
  import org.fusesource.mqtt.codec.PINGREQ;
  import org.fusesource.mqtt.codec.PINGRESP;
  import org.fusesource.mqtt.codec.PUBACK;
  import org.fusesource.mqtt.codec.PUBCOMP;
  import org.fusesource.mqtt.codec.PUBLISH;
  import org.fusesource.mqtt.codec.PUBREC;
  import org.fusesource.mqtt.codec.PUBREL;
  import org.fusesource.mqtt.codec.SUBACK;
  import org.fusesource.mqtt.codec.SUBSCRIBE;
  import org.fusesource.mqtt.codec.UNSUBSCRIBE;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * The MQTTTransportFilter normally sits on top of a TcpTransport that has been
   * configured with the StompWireFormat and is used to convert MQTT commands to
   * ActiveMQ commands. All of the conversion work is done by delegating to the
   * MQTTProtocolConverter
   */
  public class MQTTTransportFilter extends TransportFilter implements MQTTTransport {
      private static final Logger LOG = LoggerFactory.getLogger(MQTTTransportFilter.class);
      private static final Logger TRACE = LoggerFactory.getLogger(MQTTTransportFilter.class.getPackage().getName() + ".MQTTIO");
      private final MQTTProtocolConverter protocolConverter;
      private MQTTInactivityMonitor monitor;
      private MQTTWireFormat wireFormat;
      private final AtomicBoolean stopped = new AtomicBoolean();
  
      private boolean trace;
      private final Object sendLock = new Object();
  
      public MQTTTransportFilter(Transport next, WireFormat wireFormat, BrokerService brokerService) {
          super(next);
          this.protocolConverter = new MQTTProtocolConverter(this, brokerService);
  
          if (wireFormat instanceof MQTTWireFormat) {
              this.wireFormat = (MQTTWireFormat) wireFormat;
          }
      }
  
      @Override
      public void oneway(Object o) throws IOException {
          try {
              final Command command = (Command) o;
              protocolConverter.onActiveMQCommand(command);
          } catch (Exception e) {
              throw IOExceptionSupport.create(e);
          }
      }
  
      @Override
      public void onCommand(Object command) {
          try {
              MQTTFrame frame = (MQTTFrame) command;
              if (trace) {
                  TRACE.trace("Received: " + toString(frame));
              }
              protocolConverter.onMQTTCommand(frame);
          } catch (IOException e) {
              onException(e);
          } catch (JMSException e) {
              onException(IOExceptionSupport.create(e));
          }
      }
  
      @Override
      public void sendToActiveMQ(Command command) {
          TransportListener l = transportListener;
          if (l != null) {
              l.onCommand(command);
          }
      }
  
      @Override
      public void sendToMQTT(MQTTFrame command) throws IOException {
          if( !stopped.get() ) {
              if (trace) {
                  TRACE.trace("Sending : " + toString(command));
              }
              Transport n = next;
              if (n != null) {
                  // sync access to underlying transport buffer
                  synchronized (sendLock) {
                      n.oneway(command);
                  }
              }
          }
      }
  
      static private String toString(MQTTFrame frame) {
          if( frame == null )
              return null;
          try {
              switch (frame.messageType()) {
                  case PINGREQ.TYPE: return new PINGREQ().decode(frame).toString();
                  case PINGRESP.TYPE: return new PINGRESP().decode(frame).toString();
                  case CONNECT.TYPE: return new CONNECT().decode(frame).toString();
                  case DISCONNECT.TYPE: return new DISCONNECT().decode(frame).toString();
                  case SUBSCRIBE.TYPE: return new SUBSCRIBE().decode(frame).toString();
                  case UNSUBSCRIBE.TYPE: return new UNSUBSCRIBE().decode(frame).toString();
                  case PUBLISH.TYPE: return new PUBLISH().decode(frame).toString();
                  case PUBACK.TYPE: return new PUBACK().decode(frame).toString();
                  case PUBREC.TYPE: return new PUBREC().decode(frame).toString();
                  case PUBREL.TYPE: return new PUBREL().decode(frame).toString();
                  case PUBCOMP.TYPE: return new PUBCOMP().decode(frame).toString();
                  case CONNACK.TYPE: return new CONNACK().decode(frame).toString();
                  case SUBACK.TYPE: return new SUBACK().decode(frame).toString();
                  default: return frame.toString();
              }
          } catch (Throwable e) {
              LOG.warn(e.getMessage(), e);
              return frame.toString();
          }
      }
  
      @Override
      public void start() throws Exception {
          if (monitor != null) {
              monitor.startConnectChecker(getConnectAttemptTimeout());
          }
          super.start();
      }
  
      @Override
      public void stop() throws Exception {
          if (stopped.compareAndSet(false, true)) {
              super.stop();
          }
      }
  
      @Override
      public X509Certificate[] getPeerCertificates() {
          X509Certificate[] peerCerts = null;
          if (next instanceof SslTransport) {
              peerCerts = ((SslTransport) next).getPeerCertificates();
          }
          if (next instanceof  NIOSSLTransport) {
              peerCerts = ((NIOSSLTransport)next).getPeerCertificates();
          }
          if (trace && peerCerts != null) {
              LOG.debug("Peer Identity has been verified\n");
          }
          return peerCerts;
      }
  
      public boolean isTrace() {
          return trace;
      }
  
      public void setTrace(boolean trace) {
          this.trace = trace;
      }
  
      @Override
      public MQTTInactivityMonitor getInactivityMonitor() {
          return monitor;
      }
  
      public void setInactivityMonitor(MQTTInactivityMonitor monitor) {
          this.monitor = monitor;
      }
  
      @Override
      public MQTTWireFormat getWireFormat() {
          return this.wireFormat;
      }
  
      @Override
      public void onException(IOException error) {
          protocolConverter.onTransportError();
          super.onException(error);
      }
  
      public long getDefaultKeepAlive() {
          return protocolConverter != null ? protocolConverter.getDefaultKeepAlive() : -1;
      }
  
      public void setDefaultKeepAlive(long defaultHeartBeat) {
          protocolConverter.setDefaultKeepAlive(defaultHeartBeat);
      }
  
      /**
       * @return the timeout value used to fail a connection if no CONNECT frame read.
       */
      public long getConnectAttemptTimeout() {
          return wireFormat.getConnectAttemptTimeout();
      }
  
      /**
       * Sets the timeout value used to fail a connection if no CONNECT frame is read
       * in the given interval.
       *
       * @param connectTimeout
       *        the connection frame received timeout value.
       */
      public void setConnectAttemptTimeout(long connectTimeout) {
          wireFormat.setConnectAttemptTimeout(connectTimeout);
      }
  
      public boolean getPublishDollarTopics() {
          return protocolConverter != null && protocolConverter.getPublishDollarTopics();
      }
  
      public void setPublishDollarTopics(boolean publishDollarTopics) {
          protocolConverter.setPublishDollarTopics(publishDollarTopics);
      }
  
      public String getSubscriptionStrategy() {
          return protocolConverter != null ? protocolConverter.getSubscriptionStrategy() : "default";
      }
  
      public void setSubscriptionStrategy(String name) {
          protocolConverter.setSubscriptionStrategy(name);
      }
  
      public int getActiveMQSubscriptionPrefetch() {
          return protocolConverter.getActiveMQSubscriptionPrefetch();
      }
  
      /**
       * set the default prefetch size when mapping the MQTT subscription to an ActiveMQ one
       * The default = 1
       * @param activeMQSubscriptionPrefetch set the prefetch for the corresponding ActiveMQ subscription
       */
      public void setActiveMQSubscriptionPrefetch(int activeMQSubscriptionPrefetch) {
          protocolConverter.setActiveMQSubscriptionPrefetch(activeMQSubscriptionPrefetch);
      }
  
      /**
       * @return the maximum number of bytes a single MQTT message frame is allowed to be.
       */
      public int getMaxFrameSize() {
          return wireFormat.getMaxFrameSize();
      }
  
      /**
       * Sets the maximum frame size for an incoming MQTT frame.  The protocl limit is
       * 256 megabytes and this value cannot be set higher.
       *
       * @param maxFrameSize
       *        the maximum allowed frame size for a single MQTT frame.
       */
      public void setMaxFrameSize(int maxFrameSize) {
          wireFormat.setMaxFrameSize(maxFrameSize);
      }
  
      @Override
      public void setPeerCertificates(X509Certificate[] certificates) {}
  }
  