/*
 * 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 rewrite.org.apache.myfaces.extensions.scripting.startup;

import org.apache.myfaces.webapp.StartupListener;
import rewrite.org.apache.myfaces.extensions.scripting.common.util.Cast;
import rewrite.org.apache.myfaces.extensions.scripting.common.util.ClassUtils;
import rewrite.org.apache.myfaces.extensions.scripting.common.util.ReflectUtil;
import rewrite.org.apache.myfaces.extensions.scripting.context.WeavingContext;
import rewrite.org.apache.myfaces.extensions.scripting.engine.FactoryEngines;

import javax.servlet.ServletContext;
import javax.servlet.ServletContextEvent;
import java.io.IOException;
import java.util.logging.Logger;

/**
 * @author Werner Punz (latest modification by $Author$)
 * @version $Revision$ $Date$
 *          <p/>
 *          serves the startup process
 *          the chainloader hooks itself into the myfaces init process
 *          and is responsible for startup of the daemon the
 *          initial scan and compile
 */

public class StartupServletContextPluginChainLoader implements StartupListener
{
    final Logger _log = Logger.getLogger(this.getClass().getName());

    public void preInit(ServletContextEvent servletContextEvent)
    {
        ServletContext servletContext = servletContextEvent.getServletContext();
        try
        {
            WeavingContext context = WeavingContext.getInstance();
            _log.info("[EXT-SCRIPTING] Instantiating StartupServletContextPluginChainLoader");
            context.initEngines();
            _log.info("[EXT-SCRIPTING] Loading configuration");
            context.getConfiguration().init(servletContext);
            _log.info("[EXT-SCRIPTING] Loading Scripting end");

            _log.info("[EXT-SCRIPTING] Initial Scan");
            context.initialFullScan();
            _log.info("[EXT-SCRIPTING] Initial Compile");
            //we can rely on the compiler picking the files
            context.compile();
            _log.info("[EXT-SCRIPTING] init the chain loader");
            initChainLoader(servletContext);
            _log.info("[EXT-SCRIPTING] Starting Change Monitor");
            //TODO code the initial watchdog daemon start here
            _log.info("[EXT-SCRIPTING] Startup done");

        }
        catch (IOException e)
        {
            _log.severe("[EXT-SCRIPTING] Engine startup failed terminating ext-scripting");
        }

    }

    /**
     * initializes our custom chain loader which gets plugged into
     * the MyFaces loading part for classes!
     *
     * @param servletContext the servlet context to be passed down
     * @return the custom chain loader for loading our classes over our classloaders
     */
    private void initChainLoader(ServletContext servletContext)
    {
        Object loader = ReflectUtil.instantiate("org.apache.myfaces.extensions.scripting.servlet" +
                ".CustomChainLoader",
                new Cast(ServletContext.class, servletContext));
        ClassUtils.addClassLoadingExtension(loader, true);

    }

    public void postInit(ServletContextEvent evt)
    {
        //tell the system that the startup phase is done
        /*  WeavingContext.getWeaver().fullClassScan();
        evt.getServletContext().setAttribute(ScriptingConst.CTX_ATTR_STARTUP, new AtomicBoolean(Boolean.FALSE));

        WeavingContext.getExtensionEventRegistry().sendEvent(new SystemInitializedEvent());
        */
    }

    public void preDestroy(ServletContextEvent evt)
    {

    }

    public void postDestroy(ServletContextEvent evt)
    {
        //context is destroyed we have to shut down our daemon as well, by giving it
        //a hint to shutdown

        //TODO this is probably not needed because we run in a daemon thread anyway
        //so the servlet should not have a problem to shut it down externally
        /*  RefreshContext rContext = (RefreshContext) evt.getServletContext().getAttribute("RefreshContext");
        rContext.getDaemon().setRunning(false);
        */
    }
}