/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache 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.apache.org/licenses/LICENSE-2.0
 *
 * 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.apache.sling.commons.fsclassloader.impl;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import org.apache.sling.commons.classloader.ClassLoaderWriter;
import org.apache.sling.commons.fsclassloader.FSClassLoaderMBean;
import org.osgi.framework.Constants;
import org.osgi.service.component.ComponentContext;
import org.osgi.service.component.annotations.Activate;
import org.osgi.service.component.annotations.Component;
import org.osgi.service.component.annotations.Reference;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Implementation of the FSClassLoaderMBean interface
 */
@Component(
	configurationPid = FSClassLoaderProvider.SHARED_CONFIGURATION_PID,
	property = {
		Constants.SERVICE_DESCRIPTION + "=Apache Sling FSClassLoader Controller Service",
		Constants.SERVICE_VENDOR + "=The Apache Software Foundation",
		"jmx.objectname=org.apache.sling.classloader:name=FSClassLoader,type=ClassLoader"
	}
)
public class FSClassLoaderMBeanImpl implements FSClassLoaderMBean {
	private volatile File root;
	private static final Logger log = LoggerFactory.getLogger(FSClassLoaderMBeanImpl.class);

	@Reference(target = "(component.name=org.apache.sling.commons.fsclassloader.impl.FSClassLoaderProvider)")
	private ClassLoaderWriter classLoaderWriter;

	/**
	 * Activate this component. Create the root directory.
	 *
	 * @param componentContext
	 *            the component context
	 */
	@Activate
	protected void activate(final ComponentContext componentContext, final FSClassLoaderComponentConfig config) {
		// get the file root
		this.root = CacheLocationUtils.getRootDir(componentContext.getBundleContext(), config);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.apache.sling.commons.fsclassloader.FSClassLoaderMBean#
	 * getCachedScriptCount()
	 */
	@Override
	public int getCachedScriptCount() throws IOException {
		return getScripts().size();
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.apache.sling.commons.fsclassloader.FSClassLoaderMBean#
	 * getCachedScripts()
	 */
	@Override
	public List<String> getCachedScripts() {
		List<String> scripts = new ArrayList<String>();
		scripts.addAll(getScripts());
		Collections.sort(scripts);
		return scripts;
	}

	private Collection<String> getScripts() {
		Collection<String> scripts = new HashSet<String>();
		try {
			Map<String, ScriptFiles> s = new LinkedHashMap<String, ScriptFiles>();
			if (root != null) {
				FSClassLoaderWebConsole.readFiles(root, root, s);
			}
			scripts = s.keySet();
		} catch (Exception e) {
			log.warn("Exception retrieving scripts from FSClassLoader", e);
		}
		return scripts;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.apache.sling.commons.fsclassloader.FSClassLoaderMBean#clearCache()
	 */
	@Override
	public void clearCache() {
		classLoaderWriter.delete("");
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.apache.sling.commons.fsclassloader.FSClassLoaderMBean#
	 * getFSClassLoaderRoot()
	 */
	@Override
	public String getFSClassLoaderRoot() {
		return root.getAbsolutePath();
	}

}