/*
    * Copyright 2001-2004 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.juddi.v3.client;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.net.URL;
  import java.util.Enumeration;
  import java.util.jar.Attributes;
  import java.util.jar.JarFile;
  import java.util.jar.Manifest;
  
  /**
   * The release class is a utility for obtaining the version number
   */
  public class Release {
  	
  	private static final String UDDI_VERSION = "3.0";
  	private static final String JAR_NAME = "juddi-client";
  	private static String registryVersion = null;
          public static final String UNKNOWN = "unknown";
  	private Release () {
  	}
  
          /**
           * Returns the version of this jUDDI-Client jar as defined in the manifest.
           * Calls getRegistryVersion()
           * @return  the version number of the release
           * @since 3.2
           */
          public static String getjUDDIClientVersion() {
              return getRegistryVersion();
          }
          /**
           * Returns the version of this jUDDI-Client jar as defined in the manifest.
           * This function is poorly named, but left in place for backward compatibility
           * @return  the version number of the release
           */
  	public static String getRegistryVersion() {
  		if (registryVersion == null) {
  			registryVersion = getVersionFromManifest(JAR_NAME);
  		}
  		return registryVersion;
  		
  	}
  
  	public static String getUDDIVersion() {
  		return UDDI_VERSION;	
  	} 
  	
  	public static String getVersionFromManifest(String jarName) {
  		Enumeration<URL> resEnum;
          try {
              resEnum = Thread.currentThread().getContextClassLoader().getResources(JarFile.MANIFEST_NAME);
              while (resEnum.hasMoreElements()) {
                  try {
                      URL url = (URL) resEnum.nextElement();
                      if (url.toString().toLowerCase().contains(jarName)) {
                          InputStream is = url.openStream();
                          if (is != null) {
                              Manifest manifest = new Manifest(is);
                              Attributes mainAttribs = manifest.getMainAttributes();
                              String version = mainAttribs.getValue("Bundle-Version");
                              if (version != null) {
                                  return (version);
                              }
                          }
                      }
                  } catch (Exception e) {
                      // Silently ignore wrong manifests on classpath?
                  }
              }
           } catch (IOException e1) {
              // Silently ignore wrong manifests on classpath?
           }
           return UNKNOWN;
  	}
  }