/*******************************************************************************
 * Copyright (c) 2004 IBM Corporation and others.
 * 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:
 *     IBM Corporation - initial API and implementation
 *     
 *******************************************************************************/
package org.eclipse.wst.sse.core;

import org.eclipse.core.runtime.Platform;
import org.eclipse.wst.sse.core.internal.SSECorePlugin;
import org.osgi.framework.Bundle;


public class StructuredModelManager {
	private static StructuredModelManager fInstance;
	
	public static StructuredModelManager getInstance() {
		if (fInstance == null)
			fInstance = new StructuredModelManager();
		return fInstance;
	}

	public IModelManager getModelManager() {
		boolean isReady = false;
		IModelManager modelManager = null;
		while (!isReady) {
			Bundle localBundle = Platform.getBundle(SSECorePlugin.ID);
			int state = localBundle.getState();
			if (state == Bundle.ACTIVE) {
				isReady = true;
				// getInstance is a synchronized static method.
				modelManager = ModelManagerImpl.getInstance();
			} else if (state == Bundle.STARTING) {
				try {
					Thread.sleep(100);
				} catch (InterruptedException e) {
					// ignore, just loop again
				}
			} else if (state == Bundle.STOPPING) {
				isReady = true;
				modelManager = new NullModelManager();
			} else if (state == Bundle.UNINSTALLED) {
				isReady = true;
				modelManager = new NullModelManager();
			} else {
				// not sure about other states, 'resolved', 'installed'
				isReady = true;
			}
		}
		return modelManager;
	}
}