/**
 * 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.storm.starter;

import org.apache.storm.Config;
import org.apache.storm.LocalCluster;
import org.apache.storm.spout.SpoutOutputCollector;
import org.apache.storm.task.TopologyContext;
import org.apache.storm.topology.BasicOutputCollector;
import org.apache.storm.topology.OutputFieldsDeclarer;
import org.apache.storm.topology.TopologyBuilder;
import org.apache.storm.topology.base.BaseBasicBolt;
import org.apache.storm.topology.base.BaseRichSpout;
import org.apache.storm.tuple.Fields;
import org.apache.storm.tuple.Tuple;
import org.apache.storm.tuple.Values;
import org.apache.storm.utils.Utils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.HashMap;
import java.util.Map;
import java.util.Random;
import java.util.UUID;


public class AnchoredWordCount {
    public static class RandomSentenceSpout extends BaseRichSpout {
        private static final Logger LOG = LoggerFactory.getLogger(RandomSentenceSpout.class);

        SpoutOutputCollector collector;
        Random random;


        @Override
        public void open(Map conf, TopologyContext context, SpoutOutputCollector collector) {
            this.collector = collector;
            this.random = new Random();
        }

        @Override
        public void nextTuple() {
            Utils.sleep(10);
            String[] sentences = new String[]{sentence("the cow jumped over the moon"), sentence("an apple a day keeps the doctor away"),
                    sentence("four score and seven years ago"), sentence("snow white and the seven dwarfs"), sentence("i am at two with nature")};
            final String sentence = sentences[random.nextInt(sentences.length)];

            this.collector.emit(new Values(sentence), UUID.randomUUID());
        }

        protected String sentence(String input) {
            return input;
        }

        @Override
        public void ack(Object id) {
        }

        @Override
        public void fail(Object id) {
        }

        @Override
        public void declareOutputFields(OutputFieldsDeclarer declarer) {
            declarer.declare(new Fields("word"));
        }
    }


    public static class SplitSentence extends BaseBasicBolt {
        @Override
        public void execute(Tuple tuple, BasicOutputCollector collector) {
            String sentence = tuple.getString(0);
            for (String word: sentence.split("\\s+")) {
                collector.emit(new Values(word, 1));
            }
        }

        @Override
        public void declareOutputFields(OutputFieldsDeclarer declarer) {
            declarer.declare(new Fields("word", "count"));
        }
    }

    public static class WordCount extends BaseBasicBolt {
        Map<String, Integer> counts = new HashMap<String, Integer>();

        @Override
        public void execute(Tuple tuple, BasicOutputCollector collector) {
            String word = tuple.getString(0);
            Integer count = counts.get(word);
            if (count == null)
                count = 0;
            count++;
            counts.put(word, count);
            collector.emit(new Values(word, count));
        }

        @Override
        public void declareOutputFields(OutputFieldsDeclarer declarer) {
            declarer.declare(new Fields("word", "count"));
        }
    }

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

        builder.setSpout("spout", new RandomSentenceSpout(), 4);

        builder.setBolt("split", new SplitSentence(), 4).shuffleGrouping("spout");
        builder.setBolt("count", new WordCount(), 4).fieldsGrouping("split", new Fields("word"));

        Config conf = new Config();
        conf.setMaxTaskParallelism(3);

        LocalCluster cluster = new LocalCluster();
        cluster.submitTopology("word-count", conf, builder.createTopology());

        Thread.sleep(600000);

        cluster.shutdown();
    }
}
