/*
 * Copyright 2015-present Open Networking Laboratory
 *
 * Licensed 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.onosproject.openflow.controller.impl;

import org.jboss.netty.channel.ChannelPipeline;
import org.jboss.netty.channel.ChannelPipelineFactory;
import org.jboss.netty.channel.Channels;
import org.jboss.netty.handler.execution.ExecutionHandler;
import org.jboss.netty.handler.ssl.SslHandler;
import org.jboss.netty.handler.timeout.IdleStateHandler;
import org.jboss.netty.handler.timeout.ReadTimeoutHandler;
import org.jboss.netty.util.ExternalResourceReleasable;
import org.jboss.netty.util.HashedWheelTimer;
import org.jboss.netty.util.Timer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLEngine;

import static org.onlab.util.Tools.groupedThreads;

import java.util.concurrent.ThreadPoolExecutor;

/**
 * Creates a ChannelPipeline for a server-side openflow channel.
 */
public class OpenflowPipelineFactory
    implements ChannelPipelineFactory, ExternalResourceReleasable {

    private final Logger log = LoggerFactory.getLogger(getClass());


    private final SSLContext sslContext;
    protected Controller controller;
    protected ThreadPoolExecutor pipelineExecutor;
    protected Timer timer;
    protected IdleStateHandler idleHandler;
    protected ReadTimeoutHandler readTimeoutHandler;

    public OpenflowPipelineFactory(Controller controller,
                                   ThreadPoolExecutor pipelineExecutor,
                                   SSLContext sslContext) {
        super();
        this.controller = controller;
        this.pipelineExecutor = pipelineExecutor;
        this.timer = new HashedWheelTimer(groupedThreads("OpenflowPipelineFactory", "timer-%d", log));
        this.idleHandler = new IdleStateHandler(timer, 20, 25, 0);
        this.readTimeoutHandler = new ReadTimeoutHandler(timer, 30);
        this.sslContext = sslContext;
    }

    @Override
    public ChannelPipeline getPipeline() throws Exception {
        OFChannelHandler handler = new OFChannelHandler(controller);

        ChannelPipeline pipeline = Channels.pipeline();
        if (sslContext != null) {
            log.debug("OpenFlow SSL enabled.");
            SSLEngine sslEngine = sslContext.createSSLEngine();

            sslEngine.setNeedClientAuth(true);
            sslEngine.setUseClientMode(false);
            sslEngine.setEnabledProtocols(sslEngine.getSupportedProtocols());
            sslEngine.setEnabledCipherSuites(sslEngine.getSupportedCipherSuites());
            sslEngine.setEnableSessionCreation(true);

            SslHandler sslHandler = new SslHandler(sslEngine);
            pipeline.addLast("ssl", sslHandler);
        } else {
            log.debug("OpenFlow SSL disabled.");
        }
        pipeline.addLast("ofmessagedecoder", new OFMessageDecoder());
        pipeline.addLast("ofmessageencoder", new OFMessageEncoder());
        pipeline.addLast("idle", idleHandler);
        pipeline.addLast("timeout", readTimeoutHandler);
        // XXX S ONOS: was 15 increased it to fix Issue #296
        pipeline.addLast("handshaketimeout",
                         new HandshakeTimeoutHandler(handler, timer, 60));
        if (pipelineExecutor != null) {
            pipeline.addLast("pipelineExecutor",
                             new ExecutionHandler(pipelineExecutor));
        }
        pipeline.addLast("handler", handler);
        return pipeline;
    }

    @Override
    public void releaseExternalResources() {
        timer.stop();
    }
}