/* $Id: ProfileLoader.java 17940 2010-01-30 16:15:11Z euluis $

  *****************************************************************************

  * Copyright (c) 2009-2010 Contributors - see below

  * All rights reserved. This program and the accompanying materials

  * are made available under the terms of the Eclipse Public License v1.0

  * which accompanies this distribution, and is available at

  * http://www.eclipse.org/legal/epl-v10.html

  *

  * Contributors:

  *    tfmorris

  *    euluis

  *****************************************************************************

  *

  * Some portions of this file was previously release using the BSD License:

  */

 // Copyright (c) 2008 The Regents of the University of California. All

 // Rights Reserved. Permission to use, copy, modify, and distribute this

 // software and its documentation without fee, and without a written

 // agreement is hereby granted, provided that the above copyright notice

 // and this paragraph appear in all copies. This software program and

 // documentation are copyrighted by The Regents of the University of

 // California. The software program and documentation are supplied "AS

 // IS", without any accompanying services from The Regents. The Regents

 // does not warrant that the operation of the program will be

 // uninterrupted or error-free. The end-user understands that the program

 // was developed for research purposes and is advised not to rely

 // exclusively on the program for any reason. IN NO EVENT SHALL THE

 // UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,

 // SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS,

 // ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF

 // THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF

 // SUCH DAMAGE. THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY

 // WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF

 // MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE

 // PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF

 // CALIFORNIA HAS NO OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT,

 // UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

 package org.argouml.profile.init;

 import java.io.File;

 import java.io.FileFilter;

 import java.io.IOException;

 import java.net.URL;

 import java.net.URLClassLoader;

 import java.util.HashSet;

 import java.util.List;

 import java.util.Map;

 import java.util.Set;

 import java.util.StringTokenizer;

 import java.util.jar.Attributes;

 import java.util.jar.JarFile;

 import java.util.jar.Manifest;

 import org.apache.log4j.Logger;

 import org.argouml.cognitive.Critic;

 import org.argouml.i18n.Translator;

 import org.argouml.moduleloader.ModuleLoader2;

 import org.argouml.profile.ProfileException;

 import org.argouml.profile.ProfileFacade;

 import org.argouml.profile.UserDefinedProfile;

 /**

  * This is the profile loader that loads modules profiles

  * 

  * @author maurelio1234

  */

 public final class ProfileLoader {

     /**

      * Logger.

      */

     private static final Logger LOG = Logger.getLogger(ProfileLoader.class);

     /**

      * The prefix in URL:s that are jars.

      */

     private static final String JAR_PREFIX = "jar:";

     /**

      * The prefix in URL:s that are files.

      */

     private static final String FILE_PREFIX = "file:";

     /**

      * Looks for profiles in the jars in the directories used by the 

      * ModuleLoader to load modules

      */

     public void doLoad() {

         List<String> extDirs = 

             ModuleLoader2.getInstance().getExtensionLocations();

         for (String extDir : extDirs) {

             huntForProfilesInDir(extDir);

         }

     }

     private void huntForProfilesInDir(String dir) {

         LOG.info("Looking for Profiles in " + dir);

         File extensionDir = new File(dir);

         if (extensionDir.isDirectory()) {

             File[] files = extensionDir.listFiles(new JarFileFilter());

             for (File file : files) {

                 JarFile jarfile = null;

                 try {

                     jarfile = new JarFile(file);

                     if (jarfile != null) {

                         LOG.info("Looking for Profiles in the Jar "

                                 + jarfile.getName());

                         ClassLoader classloader = new URLClassLoader(

                                 new URL[] {file.toURI().toURL()});

                         loadProfilesFromJarFile(jarfile.getManifest(), file,

                                 classloader);

                     }

                 } catch (IOException ioe) {

                     LOG.debug("Cannot open Jar file " + file, ioe);

                 }

             }

         }

     }

     /**

      * Interprets the MANIFEST file in the JAR in order to load the declared

      * profile.

      * 

      * @param file the file object referencing the Jar

      * @param manifest the manifest file of the Jar

      * @param classloader the classloader that loads the classes referenced by

      *            the Jar

      */

     private void loadProfilesFromJarFile(Manifest manifest, File file,

             ClassLoader classloader) {

         Map<String, Attributes> entries = manifest.getEntries();

         boolean classLoaderAlreadyAdded = false;

         for (String entryName : entries.keySet()) {

             Attributes attr = entries.get(entryName);

             if (new Boolean(attr.getValue("Profile") + "").booleanValue()) {

                 try {

                     // we only need to add the classloader once

                     // and if and only if there is at least a profile

                     // in the JAR

                     if (!classLoaderAlreadyAdded) {

                         Translator.addClassLoader(classloader);

                         classLoaderAlreadyAdded = true;

                     }

                     Set<Critic> critics = loadJavaCriticsForProfile(attr,

                             classloader);

                     String modelPath = attr.getValue("Model");

                     URL modelURL = null;

                     if (modelPath != null) {

                         modelURL = new URL(JAR_PREFIX + FILE_PREFIX

                                 + file.getCanonicalPath() + "!" + modelPath);

                     }

                     UserDefinedProfile udp = new UserDefinedProfile(entryName,

                             modelURL, critics,

                             loadManifestDependenciesForProfile(attr),

                             ProfileFacade.getManager());

                     ProfileFacade.getManager().registerProfile(udp);

                     LOG.debug("Registered Profile: " + udp.getDisplayName()

                             + "...");

                 } catch (ProfileException e) {

                     LOG.error("Exception", e);

                 } catch (IOException e) {

                     LOG.error("Exception", e);

                 }

             }

         }

     }

     /**

      * Resolves the dependencies for a Profile

      * 

      * @param attr a group of attributes in the MANIFEST file for this JAR

      * 

      * @return the set of defined profiles

      */

     private Set<String> loadManifestDependenciesForProfile(Attributes attr) {

         Set<String> ret = new HashSet<String>();

         String value = attr.getValue("Depends-on");

         if (value != null) {

             StringTokenizer st = new StringTokenizer(value, ",");

             while (st.hasMoreElements()) {

                 String entry = st.nextToken().trim();

                 ret.add(entry);

             }

         }

         return ret;

     }

     /**

      * Loads the Java critics defined by a profile

      * 

      * @param attr the Manifest section of the profile

      * @param classloader the classloader of the Jar

      * 

      * @return the set of defined critics

      */

     private Set<Critic> loadJavaCriticsForProfile(Attributes attr,

             ClassLoader classloader) {

         Set<Critic> ret = new HashSet<Critic>();

         String value = attr.getValue("Java-Critics");

         if (value != null) {

             StringTokenizer st = new StringTokenizer(value, ",");

             while (st.hasMoreElements()) {

                 String entry = st.nextToken().trim();

                 try {

                     Class cl = classloader.loadClass(entry);

                     Critic critic = (Critic) cl.newInstance();

                     ret.add(critic);

                 } catch (ClassNotFoundException e) {

                     LOG.error("Error loading class: " + entry, e);

                 } catch (InstantiationException e) {

                     LOG.error("Error instantianting class: " + entry, e);

                 } catch (IllegalAccessException e) {

                     LOG.error("Exception", e);

                 }

             }

         }

         return ret;

     }

     /**

      * The file filter that selects Jar files.

      */

     static class JarFileFilter implements FileFilter {

         /*

          * @see java.io.FileFilter#accept(java.io.File)

          */

         public boolean accept(File pathname) {

             return (pathname.canRead()

                     && pathname.isFile()

                     && pathname.getPath().toLowerCase().endsWith(".jar"));

         }

     }

 }