/* 
 * JBoss, Home of Professional Open Source 
 * Copyright 2011 Red Hat Inc. and/or its affiliates and other contributors
 * as indicated by the @author tag. All rights reserved. 
 * See the copyright.txt in the distribution for a 
 * full listing of individual contributors.
 *
 * This copyrighted material is made available to anyone wishing to use, 
 * modify, copy, or redistribute it subject to the terms and conditions 
 * of the GNU Lesser General Public License, v. 2.1. 
 * This program is distributed in the hope that it will be useful, but WITHOUT A 
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A 
 * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details. 
 * You should have received a copy of the GNU Lesser General Public License, 
 * v.2.1 along with this distribution; if not, write to the Free Software 
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, 
 * MA  02110-1301, USA.
 */
package org.infinispan.demo.mapreduce;

import com.martiansoftware.jsap.FlaggedOption;
import com.martiansoftware.jsap.JSAP;
import com.martiansoftware.jsap.JSAPException;
import com.martiansoftware.jsap.Parameter;
import com.martiansoftware.jsap.SimpleJSAP;
import org.infinispan.Cache;
import org.infinispan.demo.Demo;
import org.infinispan.distexec.mapreduce.MapReduceTask;
import org.infinispan.util.Util;

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.nio.Buffer;
import java.nio.CharBuffer;
import java.util.List;
import java.util.Map.Entry;
import java.util.concurrent.locks.LockSupport;

/**
 * Infinispan MapReduceTask demo
 *
 * @author Vladimir Blagojevic
 */
public class WordCountDemo extends Demo {

   private String textFile;
   private int numPopularWords;

   public static void main(String... args) throws Exception {
      new WordCountDemo(args).run();
   }

   public WordCountDemo(String[] args) throws Exception {
      super(args);
      textFile = commandLineOptions.getString("textFile");
      numPopularWords = commandLineOptions.getInt("mostPopularWords");
   }

   private void run() throws Exception {

      // Step 1: start cache.
      Cache<String, String> cache = startCache();

      // Step 2: load up data file
      if (textFile != null) loadData(cache);

      // Step 3: if slave, wait.  Else, start Map/Reduce task.
      try {
         if (isMaster) {
            long start = System.currentTimeMillis();
            MapReduceTask<String, String, String, Integer> mapReduceTask = new MapReduceTask<String, String, String, Integer>(cache);

            List<Entry<String, Integer>> topList =
                  mapReduceTask
                        .mappedWith(new WordCountMapper())
                        .reducedWith(new WordCountReducer())
                        .execute(new WordCountCollator(numPopularWords));


            System.out.printf(" ---- RESULTS: Top %s words in %s ---- %n%n", numPopularWords, textFile);
            int z = 0;
            for (Entry<String, Integer> e : topList)
               System.out.printf("  %s) %s [ %,d occurences ]%n", ++z, e.getKey(), e.getValue());
            System.out.printf("%nCompleted in %s%n%n", Util.prettyPrintTime(System.currentTimeMillis() - start));
         } else {
            System.out.println("Slave node waiting for Map/Reduce tasks.  Ctrl-C to exit.");
            LockSupport.park();
         }
      } finally {
         cache.getCacheManager().stop();
      }
   }

   private void loadData(Cache<String, String> cache) throws IOException {
      FileReader in = new FileReader(textFile);
      try {
         BufferedReader bufferedReader = new BufferedReader(in);

         //chunk and insert into cache
         int chunkSize = 10; // 10K
         int chunkId = 0;

         CharBuffer cbuf = CharBuffer.allocate(1024 * chunkSize);
         while (bufferedReader.read(cbuf) >= 0) {
            Buffer buffer = cbuf.flip();
            String textChunk = buffer.toString();
            cache.put(textFile + (chunkId++), textChunk);
            cbuf.clear();
            if (chunkId % 100 == 0) System.out.printf("  Inserted %s chunks from %s into grid%n", chunkId, textFile);
         }
      } finally {
         Util.close(in);
      }
   }

   @Override
   protected SimpleJSAP buildCommandLineOptions() throws JSAPException {
      return new SimpleJSAP(
            "WordCountDemo",
            "Count words in Infinispan cache usin MapReduceTask ",
            new Parameter[]{
                  new FlaggedOption("configFile", JSAP.STRING_PARSER, "config-samples/distributed-ec2.xml",
                                    JSAP.NOT_REQUIRED, 'c', "configFile",
                                    "Infinispan transport config file"),
                  new FlaggedOption("nodeType", JSAP.STRING_PARSER, "slave", JSAP.REQUIRED,
                                    't', "nodeType", "Node type as either master or slave"),
                  new FlaggedOption("textFile", JSAP.STRING_PARSER, null, JSAP.NOT_REQUIRED,
                                    'f', "textFile", "Input text file to distribute onto grid"),
                  new FlaggedOption("mostPopularWords", JSAP.INTEGER_PARSER, "15",
                                    JSAP.NOT_REQUIRED, 'n', "mostPopularWords", "Number of most popular words to find")});
   }
}