/*
    * Copyright 2004 The Apache Software Foundation.
    * 
    * 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.apache.kandula.utility;
  
  import java.io.IOException;
  import java.net.InetAddress;
  import java.net.UnknownHostException;
  import java.security.MessageDigest;
  import java.security.NoSuchAlgorithmException;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.Map;
  import java.util.Random;
  
  import javax.xml.namespace.QName;
  
  import org.apache.axiom.om.OMElement;
  import org.apache.axiom.om.OMNamespace;
  import org.apache.axiom.om.impl.llom.factory.OMLinkedListImplFactory;
  import org.apache.axiom.soap.SOAPFactory;
  import org.apache.axis2.addressing.AddressingConstants;
  import org.apache.axis2.addressing.EndpointReference;
  import org.apache.axis2.addressing.AddressingConstants.Final;
  import org.apache.kandula.Constants;
  import org.apache.kandula.wsat.completion.CompletionInitiatorServiceListener;
  
  /***
   * @author <a href="mailto:thilina@apache.org"> Thilina Gunarathne </a>
   */
  
  public class EndpointReferenceFactory {
  
  	private static EndpointReferenceFactory instance = null;
  
  	private KandulaConfiguration configuration;
  
  	private EndpointReferenceFactory() {
  
  		configuration = KandulaConfiguration.getInstance();
  
  	}
  
  	public static EndpointReferenceFactory getInstance() {
  		if (instance == null)
  			instance = new EndpointReferenceFactory();
  		return instance;
  	}
  
  	public EndpointReference getRegistrationEndpoint(String id) {
  
  		EndpointReference epr = new EndpointReference(configuration
  				.getLocationForEPR()
  				+ "/axis2/services/RegistrationCoordinator");
  		EndpointReferenceFactory.addReferenceProperty(epr,
  				Constants.TRANSACTION_ID_PARAMETER, id);
  		return epr;
  	}
  
  	/***
  	 * Sets up a listener in the transaction initiator to recieve notify
  	 * messages mentioning the outcome of the transaction These messages include
  	 * "aborted" and "commited".
  	 * 
  	 * @throws IOException
  	 */
  	public EndpointReference getCompletionInitiatorEndpoint(String id)
  			throws IOException {
  		CompletionInitiatorServiceListener serviceListener = CompletionInitiatorServiceListener
  				.getInstance();
  		EndpointReference epr = serviceListener.getEpr();
  		EndpointReferenceFactory.addReferenceProperty(epr,
  				Constants.REQUESTER_ID_PARAMETER, id);
  		return epr;
  	}
  
  	public EndpointReference getCompletionEndpoint(String id) {
  
  		EndpointReference epr = new EndpointReference(configuration
  				.getLocationForEPR()
  				+ "/axis2/services/CompletionCoordinator");
  		EndpointReferenceFactory.addReferenceProperty(epr,
  				Constants.TRANSACTION_ID_PARAMETER, id);
  		return epr;
  	}
  
 	public EndpointReference get2PCCoordinatorEndpoint(String activityId,
 			String enlistmentId) {
 		// Activity ID to find Activity Context , EnlistmentID to find
 		// participant in activity
 		EndpointReference epr = new EndpointReference(configuration
 				.getLocationForEPR()
 				+ "/axis2/services/AtomicTransactionCoordinator");
 		EndpointReferenceFactory.addReferenceProperty(epr,
 				Constants.TRANSACTION_ID_PARAMETER, activityId);
 		EndpointReferenceFactory.addReferenceProperty(epr,
 				Constants.ENLISTMENT_ID_PARAMETER, enlistmentId);
 		return epr;
 	}
 
 	public EndpointReference get2PCParticipantEndpoint(String id) {
 
 		EndpointReference epr = new EndpointReference(configuration
 				.getLocationForEPR()
 				+ "/axis2/services/AtomicTransactionParticipant");
 		EndpointReferenceFactory.addReferenceProperty(epr,
 				Constants.REQUESTER_ID_PARAMETER, id);
 		return epr;
 	}
 
 	/***
 	 * MD5 a random string with localhost/date etc will return 128 bits
 	 * construct a string of 18 characters from those bits.
 	 * 
 	 * @return string
 	 */
 	public static String getRandomStringOf18Characters() {
 		Random myRand = new Random();
 		long rand = myRand.nextLong();
 		String sid;
 		try {
 			sid = InetAddress.getLocalHost().toString();
 		} catch (UnknownHostException e) {
 			sid = Thread.currentThread().getName();
 		}
 		long time = System.currentTimeMillis();
 		StringBuffer sb = new StringBuffer();
 		sb.append(sid);
 		sb.append(":");
 		sb.append(Long.toString(time));
 		sb.append(":");
 		sb.append(Long.toString(rand));
 		MessageDigest md5 = null;
 		try {
 			md5 = MessageDigest.getInstance("MD5");
 		} catch (NoSuchAlgorithmException e) {
 			// System.out.println("Error: " + e);
 			// todo heve to be properly handle
 		}
 		md5.update(sb.toString().getBytes());
 		byte[] array = md5.digest();
 		StringBuffer sb2 = new StringBuffer();
 		for (int j = 0; j < array.length; ++j) {
 			int b = array[j] & 0xFF;
 			sb2.append(Integer.toHexString(b));
 		}
 		int begin = myRand.nextInt();
 		if (begin < 0)
 			begin = begin * -1;
 		begin = begin % 8;
 		return new String(sb2.toString().substring(begin, begin + 18))
 				.toUpperCase();
 	}
 
 	public static void addReferenceProperty(EndpointReference epr, QName key,
 			String Value) {
 		// We'll have to live with reference parameters for the moment
 		// Since Axis2 Addressing does not support ref properties well
 		HashMap refProperties;
 		if ((refProperties = (HashMap) epr.getAllReferenceParameters()) == null) {
 			refProperties = new HashMap();
 		}
 		OMLinkedListImplFactory factory = new OMLinkedListImplFactory();
 		OMElement omElement = factory.createOMElement(key, null);
 		omElement.setText(Value);
 		refProperties.put(key, omElement);
 		epr.setReferenceParameters(refProperties);
 	}
 
 	public static EndpointReference endpointFromOM(OMElement eprElement) {
 		EndpointReference epr;
 		epr = new EndpointReference(eprElement.getFirstChildWithName(
 				new QName("Address")).getText());
 		HashMap referenceProperties = new HashMap();
 		OMElement referencePropertiesElement = eprElement
 				.getFirstChildWithName(new QName("ReferenceParameters"));
 		Iterator propertyIter = referencePropertiesElement.getChildElements();
 		while (propertyIter.hasNext()) {
 			OMElement element = (OMElement) propertyIter.next();
 
 			// TODO do we need to detach the OMElement
 			referenceProperties.put(element.getQName(), element
 					.cloneOMElement());
 		}
 		// will have to live with Ref parameters for some time :: Till axis2
 		// @ing gets stable
 		epr.setReferenceParameters(referenceProperties);
 		return epr;
 	}
 
 	public static void endpointToOM(EndpointReference epr, OMElement parentEPR,
 			SOAPFactory factory) {
 		OMNamespace wsAddressing = factory.createOMNamespace(
 				AddressingConstants.Submission.WSA_NAMESPACE,
 				AddressingConstants.WSA_DEFAULT_PREFIX);
 		OMElement addressElement = factory.createOMElement("Address",
 				wsAddressing);
 		addressElement.setText(epr.getAddress());
 		parentEPR.addChild(addressElement);
 		Map referenceValues = epr.getAllReferenceParameters();
 		if (referenceValues != null) {
 			OMElement refPropertyElement = factory.createOMElement(
 					"ReferenceParameters", wsAddressing);
 			parentEPR.addChild(refPropertyElement);
 			Iterator iterator = referenceValues.keySet().iterator();
 			while (iterator.hasNext()) {
 				QName key = (QName) iterator.next();
 				OMElement omElement = (OMElement) referenceValues.get(key);
 				refPropertyElement.addChild(omElement);
 				if (Final.WSA_NAMESPACE.equals(wsAddressing)) {
 					omElement.addAttribute(
 							Final.WSA_IS_REFERENCE_PARAMETER_ATTRIBUTE,
 							Final.WSA_TYPE_ATTRIBUTE_VALUE, wsAddressing);
 				}
 			}
 		}
 	}
 }