/**
    * Copyright 2005-2013 The Kuali Foundation
    *
    * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php
    *
   * 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.kuali.rice.core.api.resourceloader;
  
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  
  import javax.xml.namespace.QName;
  
  import org.apache.commons.lang.ObjectUtils;
  import org.apache.log4j.Logger;
  import org.kuali.rice.core.api.lifecycle.BaseLifecycle;
  import org.kuali.rice.core.api.reflect.ObjectDefinition;
  
  /**
   * A {@link ResourceLoader} which acts as a container for other ResourceLoaders.
   * Effectively, implements a composite pattern for ResourceLoaders.
   *
   * @see ResourceLoader
   *
   * @author Kuali Rice Team (rice.collab@kuali.org)
   */
  public class ResourceLoaderContainer extends BaseLifecycle implements ResourceLoader {
  
  	private static final Logger LOG = Logger.getLogger(ResourceLoaderContainer.class);
  
  	private QName name;
  
  	private List<ResourceLoader> resourceLoaders = new ArrayList<ResourceLoader>();
  
  	public ResourceLoaderContainer(QName name) {
  		this.name = name;
  	}
  
  	public void start() throws Exception {
  		for (ResourceLoader resourceLoader : this.resourceLoaders) {
  			LOG.info("Starting ResourceLoader " + resourceLoader.getName());
  			resourceLoader.start();
  		}
  		super.start();
  	}
  
  	public void stop() throws Exception {
  		while (!this.resourceLoaders.isEmpty()) {
  			ResourceLoader rl = this.resourceLoaders.get(this.resourceLoaders.size() - 1);
  			rl.stop();
  			this.resourceLoaders.remove(rl);
  		}
  
  		super.stop();
  		this.resourceLoaders.clear();
  	}
  
  	public void addResourceLoader(ResourceLoader resourceLoader) {
  		this.resourceLoaders.add(resourceLoader);
  		
  		//FIXME: RICE MODULARITY
  		moveKSBLoadersDownHack();		
  	}
  	
  	/** hack to move the ksb Resource loaders down in the RL stack. */
  	private void moveKSBLoadersDownHack() {
  		//FIXME: RICE MODULARITY 
  		for (int i = 0; i < resourceLoaders.size(); i++) {
  			final boolean remote = resourceLoaders.get(i).getName().toString().toUpperCase().contains("KSB");
  			if (remote) {
  				final ResourceLoader removed = this.resourceLoaders.remove(i);
  				this.resourceLoaders.add(this.resourceLoaders.size(), removed);
  			}
  		}
  	}
  
  	public void addResourceLoaderFirst(ResourceLoader resourceLoader) {
  		this.resourceLoaders.add(0, resourceLoader);
  
  		//FIXME: RICE MODULARITY
  		moveKSBLoadersDownHack();
  	}
  
  	public boolean containsResourceLoader(ResourceLoader resourceLoader) {
  		return this.resourceLoaders.contains(resourceLoader);
  	}
  
  	public ResourceLoader getResourceLoader(QName name) {
  
 		if (this.getName().equals(name)) {
 			return this;
 		}
 
 		for (Iterator<ResourceLoader> iter = this.resourceLoaders.iterator(); iter.hasNext();) {
 			ResourceLoader loader = iter.next();
 			if (loader.getName().equals(name)) {
 				return loader;
 			}
 			ResourceLoader loader2 = loader.getResourceLoader(name);
 			if (loader2 != null) {
 				return loader2;
 			}
 		}
 		return null;
 	}
 
 	public List<QName> getResourceLoaderNames() {
 		List<QName> names = new ArrayList<QName>();
 		for (Iterator<ResourceLoader> iter = this.resourceLoaders.iterator(); iter.hasNext();) {
 			names.add(iter.next().getName());
 		}
 		return names;
 	}
 
 	public void removeAllResourceLoaders() {
 	    this.resourceLoaders.clear();
 	}
 
 	public void removeResourceLoader(QName name) {
 		ResourceLoader loaderToRemove = null;
 		for (Iterator<ResourceLoader> iter = this.resourceLoaders.iterator(); iter.hasNext();) {
 			ResourceLoader loader = iter.next();
 			if (loader.getName().equals(name)) {
 				loaderToRemove = loader;
 			}
 		}
 		if (loaderToRemove != null) {
 			try {
 				loaderToRemove.stop();
 			} catch (Exception e) {
 				LOG.error("Failed to stop plugin " + loaderToRemove.getName() + " on removal", e);
 			}
 			this.resourceLoaders.remove(loaderToRemove);
 		}
 	}
 
 	public List<ResourceLoader> getResourceLoaders() {
 		return this.resourceLoaders;
 	}
 
 
 
 	public Object getObject(ObjectDefinition definition) {
 		for (ResourceLoader resourceLoader : this.resourceLoaders) {
 			Object object = resourceLoader.getObject(definition);
 			if (object != null) {
 				return object;
 			}
 		}
 		return null;
 	}
 
 	public Object getService(QName qname) {
 		if (LOG.isDebugEnabled()) {
 			LOG.debug("ResourceLoader " + getName() + " fetching service " + qname);
 		}
 		for (ResourceLoader resourceLoader : this.resourceLoaders) {
 			if (LOG.isDebugEnabled()) {
 				LOG.debug("Delegating fetch to " + this);
 			}
 			Object service = resourceLoader.getService(qname);
 			if (service != null) {
 				if (LOG.isDebugEnabled()) {
 					LOG.debug("Found service from " + this);
 				}
 				return service;
 			}
 		}
 		return null;
 	}
 
 	public String getContents(String indent, boolean servicePerLine) {
 		String contents = indent + this + "\n";
 
 		for (ResourceLoader resourceLoader : this.resourceLoaders) {
 			contents += resourceLoader.getContents(indent + "+++", servicePerLine);
 		}
 
 		return contents;
 	}
 
 	@Override
 	public String toString() {
 		return "Resource Loader: " + this.name + " (" + ObjectUtils.identityToString(this) + ") direct children resource loaders size: " + this.resourceLoaders.size();
 	}
 
 	public QName getName() {
 		return this.name;
 	}
 
 	public void setName(QName name) {
 		this.name = name;
 	}
 
 
 
 
 
 }