/**
 * Copyright 2010 JBoss Inc
 *
 * Licensed 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.jbpm.task.service.hornetq;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.atomic.AtomicInteger;

import org.hornetq.api.core.HornetQException;
import org.hornetq.api.core.TransportConfiguration;
import org.hornetq.api.core.client.ClientConsumer;
import org.hornetq.api.core.client.ClientMessage;
import org.hornetq.api.core.client.ClientProducer;
import org.hornetq.api.core.client.ClientSession;
import org.hornetq.api.core.client.ClientSessionFactory;
import org.hornetq.api.core.client.HornetQClient;
import org.hornetq.api.core.client.ServerLocator;
import org.hornetq.core.remoting.impl.netty.NettyConnectorFactory;
import org.hornetq.core.remoting.impl.netty.TransportConstants;
import org.jbpm.task.service.BaseClientHandler;
import org.jbpm.task.service.BaseHandler;
import org.jbpm.task.service.TaskClientConnector;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class HornetQTaskClientConnector implements TaskClientConnector {

    private static final Logger logger = LoggerFactory.getLogger(HornetQTaskClientConnector.class);
    protected ClientSession session;
    protected final BaseClientHandler handler;
    protected final String name;
    protected AtomicInteger counter;
    private String address;
    private Integer port;
    private ServerLocator serverLocator;
    private ClientProducer producer;
    private ClientConsumer consumer;

    public HornetQTaskClientConnector(String name, BaseClientHandler handler) {
        if (name == null) {
            throw new IllegalArgumentException("Name can not be null");
        }
        this.name = name;
        this.handler = handler;
        this.counter = new AtomicInteger();
    }

    public boolean connect(String address, int port) {
        this.port = port;
        this.address = address;
        return connect();
    }

    public boolean connect() {
        if (session != null && !session.isClosed()) {
            throw new IllegalStateException("Already connected. Disconnect first.");
        }
        try {
            Map<String, Object> connectionParams = new HashMap<String, Object>();
            if (address == null) {
                address = "127.0.0.1";
            }
            if (port == null) {
                port = 5445;
            }
            connectionParams.put(TransportConstants.PORT_PROP_NAME, port);
            connectionParams.put(TransportConstants.HOST_PROP_NAME, address);

            TransportConfiguration transportConfiguration = new TransportConfiguration(NettyConnectorFactory.class.getCanonicalName(), connectionParams);
            serverLocator = HornetQClient.createServerLocatorWithoutHA(transportConfiguration);
            ClientSessionFactory factory = serverLocator.createSessionFactory(transportConfiguration);
            session = factory.createSession();
            producer = session.createProducer(HornetQTaskServer.SERVER_TASK_COMMANDS_QUEUE);

            createClientQueue();

            Thread responsesThread = new Thread(new Runnable() {

                public void run() {
                    try {
                        consumer = session.createConsumer(name);
                    } catch (HornetQException e) {
                        logger.error("Error creating consumer. ", e);
                        if (e.getCode() == HornetQException.OBJECT_CLOSED) {
                            logger.info(e.getMessage());
                            return;
                        }
                        throw new RuntimeException("Client Exception with class " + getClass()
                                + " using port " + port, e);
                    }


                    while (true) {
                        try {
                            ClientMessage serverMessage = consumer.receive();
                            if (serverMessage != null) {
                                ((HornetQTaskClientHandler) handler).messageReceived(session, readMessage(serverMessage), BaseHornetQTaskServer.SERVER_TASK_COMMANDS_QUEUE);
                            }
                        } catch (HornetQException e) {
                            if (e.getCode() != HornetQException.OBJECT_CLOSED) {
                                logger.error(e.getMessage());
				return;
                            }

                        } catch (Exception e) {
                            // LOG the exception and continue receiving
							// messages.
                            logger.error(e.getMessage());
                        }
                    }

                }
            });
            responsesThread.start();
            session.start();
            return true;
        } catch (Exception e) {
            logger.error(e.getMessage());
            return false;
        }
    }

    private Object readMessage(ClientMessage serverMessage) throws IOException, ClassNotFoundException {
        int bodySize = serverMessage.getBodySize();
        byte[] message = new byte[bodySize];
        serverMessage.getBodyBuffer().readBytes(message);
        ByteArrayInputStream bais = new ByteArrayInputStream(message);
        ObjectInputStream ois = new ObjectInputStream(bais);
        return ois.readObject();
    }

    private void createClientQueue() {
        try {
            session.createQueue(name, name, true);
        } catch (HornetQException e) {
            if (e.getCode() != HornetQException.QUEUE_EXISTS) {
                throw new RuntimeException("Client Exception with class " + getClass() + " using port " + port, e);
            }
            logger.info(e.getMessage());
        }
    }

    public void disconnect() throws Exception {
        if (session != null && !session.isClosed()) {
            session.close();
            producer.close();
            if (consumer != null) {
                consumer.close();
            }
            serverLocator.close();
        }
    }

    public void write(Object object) {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        ObjectOutputStream oout;
        try {
            oout = new ObjectOutputStream(baos);
            oout.writeObject(object);
            ClientMessage message = session.createMessage(true);
            message.getBodyBuffer().writeBytes(baos.toByteArray());
            message.putStringProperty("producerId", name);
            producer.send(message);
        } catch (IOException e) {
            throw new RuntimeException("Error creating message", e);
        } catch (HornetQException e) {
            throw new RuntimeException("Error writing message", e);
        }
    }

    public AtomicInteger getCounter() {
        return counter;
    }

    public BaseHandler getHandler() {
        return handler;
    }

    public String getName() {
        return name;
    }
}