/*
    * Copyright 2001-2011 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.juddi.v3.client.mapping;
  
  import java.util.Properties;
  
  public class PolicyLocalFirst extends PolicyRoundRobin {
  
  	public final static String JUDDI_CLIENT_LOCAL   = "juddi.client.local";
  	public final static String DEFAULT_CLIENT_LOCAL = "localhost";
  	private static String local;
  	
  	/**
  	 * This policy prefers 'local' EPR over remote EPRs. By default 'local' means
  	 * the EPR contains the String 'localhost'. This setting can be overwritten
  	 * by setting the 'juddi.client.local' property. An example would be 'localhost:8080'.
  	 * 
  	 * @param properties
  	 */
  	public PolicyLocalFirst(Properties properties) {
  		super(properties);
  		init(properties);
  	}
          
          private static synchronized void init(Properties properties){
                  if (properties!=null) {
  			local = properties.getProperty(JUDDI_CLIENT_LOCAL, DEFAULT_CLIENT_LOCAL);
  		} else {
  			local = DEFAULT_CLIENT_LOCAL;
  		}
          }
  	
  	public String select(Topology topology) {
  		
  		if (topology.getEprs().size()==0) return null;
  		
  		if ((topology.getHasLocal()==null)) {
  			int pointer = 0;
  			topology.setHasLocal(Boolean.FALSE);
  			for (String epr : topology.getEprs()) {
  				if (epr.toLowerCase().contains(local.toLowerCase())) {
  					topology.setPointer(pointer);
  					topology.setHasLocal(Boolean.TRUE);
  					break;
  				}
  				pointer++;
  			}
  			
  		}
  		
  		if (topology.getHasLocal()) {
  			//return the localEpr
  			return topology.getEprs().get(topology.getPointer());
  		} else {
  			//no local EPR, fall back on roundrobin
  			return super.select(topology);
  		}
  	}
  
  }