/*
 * 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.pirk.responder.wideskies;

import java.security.Permission;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.util.ToolRunner;
import org.apache.pirk.query.wideskies.Query;
import org.apache.pirk.responder.wideskies.mapreduce.ComputeResponseTool;
import org.apache.pirk.responder.wideskies.spark.ComputeResponse;
import org.apache.pirk.responder.wideskies.spark.streaming.ComputeStreamingResponse;
import org.apache.pirk.responder.wideskies.standalone.Responder;
import org.apache.pirk.responder.wideskies.storm.PirkTopology;
import org.apache.pirk.serialization.LocalFileSystemStore;
import org.apache.pirk.utils.SystemConfiguration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Driver class for the responder
 * <p>
 * Pivots on the platform given
 * <p>
 * If mapreduce, kick off with 'hadoop jar' command.
 * <p>
 * If spark, kick off with 'spark-submit' command or integrate into other codeflows with SparkLauncher
 * <p>
 * If standalone, assumes that the target data is in the local filesystem in JSON format with one JSON record per line
 * 
 */
public class ResponderDriver
{
  private static final Logger logger = LoggerFactory.getLogger(ResponderDriver.class);

  private enum Platform
  {
    MAPREDUCE, SPARK, SPARKSTREAMING, STORM, STANDALONE, NONE
  }

  public static void main(String[] args) throws Exception
  {
    ResponderCLI responderCLI = new ResponderCLI(args);

    // For handling System.exit calls from Spark Streaming
    System.setSecurityManager(new SystemExitManager());

    Platform platform = Platform.NONE;
    String platformString = SystemConfiguration.getProperty(ResponderProps.PLATFORM);
    try
    {
      platform = Platform.valueOf(platformString.toUpperCase());
    } catch (IllegalArgumentException e)
    {
      logger.error("platform " + platformString + " not found.");
    }

    logger.info("platform = " + platform);
    switch (platform)
    {
      case MAPREDUCE:
        logger.info("Launching MapReduce ResponderTool:");

        ComputeResponseTool pirWLTool = new ComputeResponseTool();
        ToolRunner.run(pirWLTool, new String[] {});
        break;

      case SPARK:
        logger.info("Launching Spark ComputeResponse:");

        ComputeResponse computeResponse = new ComputeResponse(FileSystem.get(new Configuration()));
        computeResponse.performQuery();
        break;

      case SPARKSTREAMING:
        logger.info("Launching Spark ComputeStreamingResponse:");

        ComputeStreamingResponse computeSR = new ComputeStreamingResponse(FileSystem.get(new Configuration()));
        try
        {
          computeSR.performQuery();
        } catch (SystemExitException e)
        {
          // If System.exit(0) is not caught from Spark Streaming,
          // the application will complete with a 'failed' status
          logger.info("Exited with System.exit(0) from Spark Streaming");
        }

        // Teardown the context
        computeSR.teardown();
        break;

      case STORM:
        logger.info("Launching Storm PirkTopology:");
        PirkTopology.runPirkTopology();
        break;

      case STANDALONE:
        logger.info("Launching Standalone Responder:");

        String queryInput = SystemConfiguration.getProperty("pir.queryInput");
        Query query = new LocalFileSystemStore().recall(queryInput, Query.class);

        Responder pirResponder = new Responder(query);
        pirResponder.computeStandaloneResponse();
        break;
    }
  }

  // Exception and Security Manager classes used to catch System.exit from Spark Streaming
  private static class SystemExitException extends SecurityException
  {}

  private static class SystemExitManager extends SecurityManager
  {
    @Override
    public void checkPermission(Permission perm)
    {}

    @Override
    public void checkExit(int status)
    {
      super.checkExit(status);
      if (status == 0) // If we exited cleanly, throw SystemExitException
      {
        throw new SystemExitException();
      }
      else
      {
        throw new SecurityException();
      }

    }
  }
}