/*
    * 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.hadoop.chukwa.extraction.archive;
  
  
  import java.io.IOException;
  import java.util.Iterator;
  import org.apache.hadoop.chukwa.ChukwaArchiveKey;
  import org.apache.hadoop.chukwa.ChunkImpl;
  import org.apache.hadoop.chukwa.conf.ChukwaConfiguration;
  import org.apache.hadoop.conf.Configured;
  import org.apache.hadoop.fs.Path;
  import org.apache.hadoop.mapred.FileInputFormat;
  import org.apache.hadoop.mapred.FileOutputFormat;
  import org.apache.hadoop.mapred.JobClient;
  import org.apache.hadoop.mapred.JobConf;
  import org.apache.hadoop.mapred.MapReduceBase;
  import org.apache.hadoop.mapred.OutputCollector;
  import org.apache.hadoop.mapred.Reducer;
  import org.apache.hadoop.mapred.Reporter;
  import org.apache.hadoop.mapred.SequenceFileInputFormat;
  import org.apache.hadoop.mapred.lib.IdentityMapper;
  import org.apache.hadoop.util.Tool;
  import org.apache.hadoop.util.ToolRunner;
  import org.apache.log4j.Logger;
  
  /**
   * Main class for mapreduce job to do archiving of Chunks.
   * 
   * Map class and reduce classes are both identity; actual logic is in 
   * Partitioner and OutputFormat classes.  Those are selected by first argument.
   * 
   * 
   *
   */
  public class ChukwaArchiveBuilder extends Configured implements Tool {
    
    
    static class UniqueKeyReduce extends MapReduceBase implements
    Reducer<ChukwaArchiveKey, ChunkImpl, ChukwaArchiveKey, ChunkImpl> {
  
      /**
       * Outputs exactly one value for each key; this suppresses duplicates
       */
      @Override
      public void reduce(ChukwaArchiveKey key, Iterator<ChunkImpl> vals,
          OutputCollector<ChukwaArchiveKey, ChunkImpl> out, Reporter r)
          throws IOException {
        ChunkImpl i = vals.next();
        out.collect(key, i);
        int dups = 0;
        while(vals.hasNext()) {
          vals.next();
          dups ++;
        }
        r.incrCounter("app", "duplicate chunks", dups);
      }
    
    }
    static Logger log = Logger.getLogger(ChukwaArchiveBuilder.class);
  
    static int printUsage() {
      System.out
          .println("ChukwaArchiveBuilder <Stream/DataType/Daily/Hourly> <input> <output>");
      ToolRunner.printGenericCommandUsage(System.out);
      return -1;
    }
  
    public int run(String[] args) throws Exception {
  
      // Make sure there are exactly 3 parameters left.
      if (args.length != 3) {
        System.out.println("ERROR: Wrong number of parameters: " + args.length
            + " instead of 3.");
        return printUsage();
      }
      JobConf jobConf = new JobConf(getConf(), ChukwaArchiveBuilder.class);
  
      jobConf.setInputFormat(SequenceFileInputFormat.class);
  
      jobConf.setMapperClass(IdentityMapper.class);
      
      jobConf.setReducerClass(UniqueKeyReduce.class);
 //    jobConf.setReducerClass(IdentityReducer.class);
 
     if (args[0].equalsIgnoreCase("Daily")) {
       jobConf.setPartitionerClass(ChukwaArchiveDailyPartitioner.class);
       jobConf.setOutputFormat(ChukwaArchiveDailyOutputFormat.class);
       jobConf.setJobName("Chukwa-DailyArchiveBuilder");
     } else if (args[0].equalsIgnoreCase("Hourly")) {
       jobConf.setJobName("Chukwa-HourlyArchiveBuilder");
       jobConf.setPartitionerClass(ChukwaArchiveHourlyPartitioner.class);
       jobConf.setOutputFormat(ChukwaArchiveHourlyOutputFormat.class);
     } else if (args[0].equalsIgnoreCase("DataType")) {
       jobConf.setJobName("Chukwa-ArchiveBuilder-DataType");
       int reduceCount = jobConf.getInt("chukwaArchiveBuilder.reduceCount", 1);
       log.info("Reduce Count:" + reduceCount);
       jobConf.setNumReduceTasks(reduceCount);
 
       jobConf.setPartitionerClass(ChukwaArchiveDataTypePartitioner.class);
       jobConf.setOutputFormat(ChukwaArchiveDataTypeOutputFormat.class);
     } else if (args[0].equalsIgnoreCase("Stream")) {
       jobConf.setJobName("Chukwa-HourlyArchiveBuilder-Stream");
       int reduceCount = jobConf.getInt("chukwaArchiveBuilder.reduceCount", 1);
       log.info("Reduce Count:" + reduceCount);
       jobConf.setNumReduceTasks(reduceCount);
 
       jobConf.setPartitionerClass(ChukwaArchiveStreamNamePartitioner.class);
       jobConf.setOutputFormat(ChukwaArchiveStreamNameOutputFormat.class);
     } else {
       System.out.println("ERROR: Wrong Time partionning: " + args[0]
           + " instead of [Stream/DataType/Hourly/Daily].");
       return printUsage();
     }
 
     jobConf.setOutputKeyClass(ChukwaArchiveKey.class);
     jobConf.setOutputValueClass(ChunkImpl.class);
 
     FileInputFormat.setInputPaths(jobConf, args[1]);
     FileOutputFormat.setOutputPath(jobConf, new Path(args[2]));
 
     JobClient.runJob(jobConf);
     return 0;
   }
 
   public static void main(String[] args) throws Exception {
     int res = ToolRunner.run(new ChukwaConfiguration(), new ChukwaArchiveBuilder(),
         args);
     return;
   }
 }