/**
 * 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.apex.benchmark.hive;

import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.Map;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.apache.apex.benchmark.RandomMapOutput;
import org.apache.apex.malhar.hive.AbstractFSRollingOutputOperator;
import org.apache.apex.malhar.hive.HiveOperator;
import org.apache.apex.malhar.hive.HiveStore;
import org.apache.apex.malhar.lib.testbench.RandomEventGenerator;
import org.apache.hadoop.conf.Configuration;

import com.datatorrent.api.Context.PortContext;
import com.datatorrent.api.DAG;
import com.datatorrent.api.StreamingApplication;
import com.datatorrent.api.annotation.ApplicationAnnotation;


/**
 * Application used to benchmark HIVE Map Insert operator
 * The DAG consists of random Event generator operator that is
 * connected to random map output operator that writes to a file in HDFS.&nbsp;
 * The map output operator is connected to hive Map Insert output operator which writes
 * the contents of HDFS file to hive tables.
 * <p>
 *
 * @since 2.1.0
 */
@ApplicationAnnotation(name = "HiveMapInsertBenchmarkingApp")
public class HiveMapInsertBenchmarkingApp implements StreamingApplication
{
  Logger LOG = LoggerFactory.getLogger(HiveMapInsertBenchmarkingApp.class);

  @Override
  public void populateDAG(DAG dag, Configuration conf)
  {
    HiveStore store = new HiveStore();
    store.setDatabaseUrl(conf.get("dt.application.HiveMapInsertBenchmarkingApp.operator.HiveOperator.store.dbUrl"));
    store.setConnectionProperties(conf.get(
        "dt.application.HiveMapInsertBenchmarkingApp.operator.HiveOperator.store.connectionProperties"));
    store.setFilepath(conf.get("dt.application.HiveMapInsertBenchmarkingApp.operator.HiveOperator.store.filepath"));
    try {
      hiveInitializeMapDatabase(store, conf.get(
          "dt.application.HiveMapInsertBenchmarkingApp.operator.HiveOperator.tablename"), ":");
    } catch (SQLException ex) {
      LOG.debug(ex.getMessage());
    }
    dag.setAttribute(DAG.STREAMING_WINDOW_SIZE_MILLIS, 1000);
    RandomEventGenerator eventGenerator = dag.addOperator("EventGenerator", RandomEventGenerator.class);
    RandomMapOutput mapGenerator = dag.addOperator("MapGenerator", RandomMapOutput.class);
    dag.setAttribute(eventGenerator, PortContext.QUEUE_CAPACITY, 10000);
    dag.setAttribute(mapGenerator, PortContext.QUEUE_CAPACITY, 10000);
    HiveOperator hiveInsert = dag.addOperator("HiveOperator", new HiveOperator());
    hiveInsert.setStore(store);
    FSRollingMapTestImpl rollingMapFsWriter = dag.addOperator("RollingFsMapWriter", new FSRollingMapTestImpl());
    rollingMapFsWriter.setFilePath(store.filepath);
    ArrayList<String> hivePartitionColumns = new ArrayList<String>();
    hivePartitionColumns.add("dt");
    hiveInsert.setHivePartitionColumns(hivePartitionColumns);
    dag.addStream("EventGenerator2Map", eventGenerator.integer_data, mapGenerator.input);
    dag.addStream("MapGenerator2HdfsOutput", mapGenerator.map_data, rollingMapFsWriter.input);
    dag.addStream("FsWriter2Hive", rollingMapFsWriter.outputPort, hiveInsert.input);

  }

  /*
   * User can create table and specify data columns and partition columns in this function.
   */
  public static void hiveInitializeMapDatabase(
      HiveStore hiveStore, String tablename, String delimiterMap) throws SQLException
  {
    hiveStore.connect();
    Statement stmt = hiveStore.getConnection().createStatement();
    stmt.execute("CREATE TABLE IF NOT EXISTS " + tablename
        + " (col1 map<string,int>) PARTITIONED BY(dt STRING) ROW FORMAT DELIMITED FIELDS TERMINATED BY '\n'  \n"
        + "MAP KEYS TERMINATED BY '" + delimiterMap + "' \n"
        + "STORED AS TEXTFILE ");
    hiveStore.disconnect();
  }

  public static class FSRollingMapTestImpl extends AbstractFSRollingOutputOperator<Map<String, Object>>
  {
    public String delimiter = ":";

    public String getDelimiter()
    {
      return delimiter;
    }

    public void setDelimiter(String delimiter)
    {
      this.delimiter = delimiter;
    }

    @Override
    public ArrayList<String> getHivePartition(Map<String, Object> tuple)
    {
      ArrayList<String> hivePartitions = new ArrayList<String>();
      hivePartitions.add(tuple.toString());
      return (hivePartitions);
    }

    @Override
    protected byte[] getBytesForTuple(Map<String, Object> tuple)
    {
      Iterator<String> keyIter = tuple.keySet().iterator();
      StringBuilder writeToHive = new StringBuilder("");

      while (keyIter.hasNext()) {
        String key = keyIter.next();
        Object obj = tuple.get(key);
        writeToHive.append(key).append(delimiter).append(obj).append("\n");
      }
      return writeToHive.toString().getBytes();
    }

  }

}