/*******************************************************************************
 * Copyright (c) 2010, 2015 Oracle.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * and Apache License v2.0 which accompanies this distribution. 
 * The Eclipse Public License is available at
 *     http://www.eclipse.org/legal/epl-v10.html
 * and the Apache License v2.0 is available at 
 *     http://www.opensource.org/licenses/apache2.0.php.
 * You may elect to redistribute this code under either of these licenses.
 *
 * Contributors:
 *     Bob Nettleton (Oracle) - Initial Reference Implementation
 ******************************************************************************/  

package org.eclipse.gemini.naming;

import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import org.osgi.framework.Bundle;
import org.osgi.framework.BundleContext;
import org.osgi.framework.BundleEvent;
import org.osgi.framework.ServiceFactory;
import org.osgi.framework.ServiceRegistration;
import org.osgi.framework.SynchronousBundleListener;

class ContextManagerServiceFactoryImpl implements ServiceFactory {

	// map of bundles to context managers (CloseableContextManager)
	private Map m_mapOfManagers = 
		Collections.synchronizedMap(new HashMap());
	
	/* BundleContext for the Gemini Naming Implementation Bundle */
	private final BundleContext m_implBundleContext;
	
	ContextManagerServiceFactoryImpl(BundleContext implBundleContext) {
		m_implBundleContext = implBundleContext;
	}
	
	@Override
	public Object getService(Bundle bundle, ServiceRegistration registration) {
		CloseableContextManager contextManager = 
			createContextManager(bundle, m_implBundleContext);
		m_mapOfManagers.put(bundle, contextManager);
		bundle.getBundleContext().addBundleListener(new ContextManagerBundleListener());
		return contextManager;
	}

	

	@Override
	public void ungetService(Bundle bundle, ServiceRegistration registration, Object service) {
		closeContextManager(bundle);
	}
	
	protected void closeAll() {
		synchronized(m_mapOfManagers) {
			Iterator iterator = m_mapOfManagers.entrySet().iterator();
			while(iterator.hasNext()) {
				Map.Entry currentMapEntry = (Map.Entry) iterator.next();
				Object currentMapEntryValue = currentMapEntry.getValue();
				if (currentMapEntryValue != null){
					((CloseableContextManager)currentMapEntryValue).close();
					iterator.remove();
				}
			}
		}
	}

	private void closeContextManager(Bundle bundle) {
		CloseableContextManager contextManager = 
			(CloseableContextManager)m_mapOfManagers.get(bundle);
		if(contextManager != null) {
			contextManager.close();
			m_mapOfManagers.remove(bundle);
		}
	}
	
	
	private class ContextManagerBundleListener implements SynchronousBundleListener {
		@Override
		public void bundleChanged(BundleEvent event) {
			if(event.getType() == BundleEvent.STOPPED) {
				if(m_mapOfManagers.containsKey(event.getBundle())) {
					closeContextManager(event.getBundle());
				}
			}
		}
		
	}
	
	
	/**
	 * Convenience factory method for creating a CloseableContextManager
	 * instance.  
	 * @param bundle the Bundle associated with this context manager
	 * @return a CloseableContextManager that will handle requests for 
	 *         the given Bundle.  
	 */
	private static CloseableContextManager createContextManager(Bundle bundle, BundleContext implBundleContext) {
		return new SecurityAwareContextManagerImpl(new ContextManagerImpl(bundle, implBundleContext));
	}
}