/*
 * 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.hyracks.control.cc.web;

import java.util.EnumSet;
import java.util.logging.Logger;

import javax.servlet.DispatcherType;

import org.apache.wicket.Application;
import org.apache.wicket.RuntimeConfigurationType;
import org.apache.wicket.protocol.http.ContextParamWebApplicationFactory;
import org.apache.wicket.protocol.http.WicketFilter;
import org.eclipse.jetty.server.Connector;
import org.eclipse.jetty.server.Handler;
import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.server.handler.ContextHandler;
import org.eclipse.jetty.server.handler.ContextHandlerCollection;
import org.eclipse.jetty.server.handler.HandlerCollection;
import org.eclipse.jetty.server.nio.SelectChannelConnector;
import org.eclipse.jetty.servlet.DefaultServlet;
import org.eclipse.jetty.servlet.FilterHolder;
import org.eclipse.jetty.servlet.ServletContextHandler;

import org.apache.hyracks.control.cc.ClusterControllerService;
import org.apache.hyracks.control.cc.adminconsole.HyracksAdminConsoleApplication;
import org.apache.hyracks.control.cc.web.util.JSONOutputRequestHandler;
import org.apache.hyracks.control.cc.web.util.RoutingHandler;

public class WebServer {
    private final static Logger LOGGER = Logger.getLogger(WebServer.class.getName());

    private final ClusterControllerService ccs;
    private final Server server;
    private final SelectChannelConnector connector;
    private final HandlerCollection handlerCollection;

    public WebServer(ClusterControllerService ccs) throws Exception {
        this.ccs = ccs;
        server = new Server();

        connector = new SelectChannelConnector();

        server.setConnectors(new Connector[] { connector });

        handlerCollection = new ContextHandlerCollection();
        server.setHandler(handlerCollection);
        addHandlers();
    }

    private void addHandlers() {
        ContextHandler handler = new ContextHandler("/rest");
        RoutingHandler rh = new RoutingHandler();
        rh.addHandler("jobs", new JSONOutputRequestHandler(new JobsRESTAPIFunction(ccs)));
        rh.addHandler("nodes", new JSONOutputRequestHandler(new NodesRESTAPIFunction(ccs)));
        rh.addHandler("statedump", new JSONOutputRequestHandler(new StateDumpRESTAPIFunction(ccs)));
        handler.setHandler(rh);
        addHandler(handler);

        addHandler(createAdminConsoleHandler());
        addHandler(createStaticResourcesHandler());

        /** the service of uploading/downloading deployment jars */
        handler = new ContextHandler("/applications");
        handler.setHandler(new ApplicationInstallationHandler(ccs));
        addHandler(handler);
    }

    private Handler createAdminConsoleHandler() {
        FilterHolder filter = new FilterHolder(WicketFilter.class);
        filter.setInitParameter(ContextParamWebApplicationFactory.APP_CLASS_PARAM,
                HyracksAdminConsoleApplication.class.getName());
        filter.setInitParameter(WicketFilter.FILTER_MAPPING_PARAM, "/*");
        filter.setInitParameter(Application.CONFIGURATION, RuntimeConfigurationType.DEPLOYMENT.toString());

        ServletContextHandler handler = new ServletContextHandler(ServletContextHandler.SESSIONS);
        handler.setContextPath("/adminconsole");
        handler.setAttribute(ClusterControllerService.class.getName(), ccs);
        handler.addFilter(filter, "/*", EnumSet.of(DispatcherType.REQUEST, DispatcherType.ERROR));
        handler.addServlet(DefaultServlet.class, "/");
        return handler;
    }

    private Handler createStaticResourcesHandler() {
        String staticDir = WebServer.class.getClassLoader().getResource("static").toExternalForm();
        ServletContextHandler handler = new ServletContextHandler(ServletContextHandler.SESSIONS);
        handler.setContextPath("/static");
        handler.setResourceBase(staticDir);
        handler.addServlet(DefaultServlet.class, "/");
        return handler;
    }

    public void setPort(int port) {
        connector.setPort(port);
    }

    public int getListeningPort() {
        return connector.getLocalPort();
    }

    public void start() throws Exception {
        server.start();
    }

    public void stop() throws Exception {
        server.stop();
    }

    public void addHandler(Handler handler) {
        handlerCollection.addHandler(handler);
    }
}