/*
 * JBoss, Home of Professional Open Source
 * Copyright 2005-2008, Red Hat Middleware LLC, and individual contributors
 * by the @authors tag. See the copyright.txt in the distribution for a
 * full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */

package org.jboss.messaging.util;

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

import org.jboss.messaging.core.logging.Logger;
import org.jboss.messaging.core.version.Version;
import org.jboss.messaging.core.version.impl.VersionImpl;

/**
 * This loads the version info in from a version.properties file.
 *
 * @author <a href="ataylor@redhat.com">Andy Taylor</a>
 * @author <a href="csuconic@redhat.com">Clebert Suconic</a>
 */
public class VersionLoader
{

   private static final Logger log = Logger.getLogger(VersionLoader.class);

   
   private static Version version;
   
   static
   {
      try
      {
         version = load();
      }
      catch (Throwable e)
      {
         version = null;
         log.error(e.getMessage(), e);
      }
      
   }

   public static Version getVersion()
   {
      if (version == null)
      {
         throw new RuntimeException("version.properties is not available");
      }
      
      return version;
   }
   
   private static Version load()
   {
      Properties versionProps = new Properties();
      InputStream in = VersionImpl.class.getClassLoader().getResourceAsStream("version.properties");
      try
      {
         if (in == null)
         {
            throw new RuntimeException("version.properties is not available");
         }
         try
         {
            versionProps.load(in);
            String versionName = versionProps.getProperty("messaging.version.versionName");
            int majorVersion = Integer.valueOf(versionProps.getProperty("messaging.version.majorVersion"));
            int minorVersion = Integer.valueOf(versionProps.getProperty("messaging.version.minorVersion"));
            int microVersion = Integer.valueOf(versionProps.getProperty("messaging.version.microVersion"));
            int incrementingVersion = Integer.valueOf(versionProps.getProperty("messaging.version.incrementingVersion"));
            String versionSuffix = versionProps.getProperty("messaging.version.versionSuffix");
            return new VersionImpl(versionName,
                                   majorVersion,
                                   minorVersion,
                                   microVersion,
                                   incrementingVersion,
                                   versionSuffix);
         }
         catch (IOException e)
         {
            //if we get here then the messaging hasnt been built properly and the version.properties is skewed in some way
            throw new RuntimeException("unable to load version.properties", e);
         }
      }
      finally
      {
         try
         {
            in.close();
         }
         catch (Throwable ignored)
         {
         }
      }

   }
}