package main;

import java.util.AbstractMap;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Collections;
import java.util.Date;
import java.util.List;
import java.util.Map;
import java.util.Random;
import java.util.Timer;
import java.util.TimerTask;
import java.util.Map.Entry;

import org.elasticsearch.action.bulk.BulkRequestBuilder;
import org.elasticsearch.action.bulk.BulkResponse;
import org.elasticsearch.action.deletebyquery.DeleteByQueryRequestBuilder;
import org.elasticsearch.action.index.IndexRequestBuilder;
import org.elasticsearch.action.search.SearchRequestBuilder;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.Client;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.common.xcontent.XContentFactory;
import org.elasticsearch.index.query.FilterBuilders;
import org.elasticsearch.index.query.QueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.QueryStringQueryBuilder.Operator;
import org.elasticsearch.node.NodeBuilder;
import org.elasticsearch.search.sort.SortOrder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.gson.Gson;

public class ElasticSearchBug {

    private static String charset = "abcdefghijklmnopqrstuvwxyz";

    public static String word()
    {
        Random rand = new Random();
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < 4; i++)
        {
            int c = rand.nextInt(charset.length());
            sb.append(charset.charAt(c));
        }
        return sb.toString();
    }

    public static String content()
    {
        Random rand = new Random();
        int s = rand.nextInt(30);
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < s; i++)
        {
            sb.append(word());
        }
        return sb.toString();
    }

    public static void main(String[] args) throws InterruptedException
    {
        ElasticSearchIndexerBug es = new ElasticSearchIndexerBug();
        SearchTask st0 = new SearchTask(es);
        InsertTask it0 = new InsertTask(es);

        st0.run();
        it0.run();

        st0.join();
        it0.join();
    }

    private static class SearchTask
        extends Thread {
        private ElasticSearchIndexerBug es;
        private Date date = new Date();

        public SearchTask(ElasticSearchIndexerBug es)
        {
            this.es = es;
        }

        @Override
        public void run()
        {
            for (int i = 0; i < 1000; i++)
            {
                es.search(word(), "TWITTER", date.getTime(), "EN");
                try
                {
                    sleep(10);
                }
                catch (InterruptedException e)
                {
                    e.printStackTrace();
                }
            }

        }
    }

    private static class InsertTask
        extends Thread {
        private ElasticSearchIndexerBug es;

        public InsertTask(ElasticSearchIndexerBug es)
        {
            this.es = es;
        }

        @Override
        public void run()
        {
            for (int i = 0; i < 500; i++)
            {
                PostBug p = new PostBug();
                p.setContent(content());
                p.setUploadDate(Calendar.getInstance());
                p.setLanguage("EN");
                es.addIndex(p);
                try
                {
                    sleep(50);
                }
                catch (InterruptedException e)
                {
                    e.printStackTrace();
                }
            }
        }
    }

    private static class PostBug {
        private String content;
        private Calendar uploadDate;
        private String language;

        public void setContent(String content)
        {
            this.content = content;
        }

        public String getExtendedContent()
        {
            return this.content;
        }

        public void setUploadDate(Calendar uploadDate)
        {
            this.uploadDate = uploadDate;
        }

        public Calendar getUploadDate()
        {
            return this.uploadDate;
        }

        public void setLanguage(String language)
        {
            this.language = language;
        }

        public String getLanguage()
        {
            return this.language;
        }

    }

    private static class ProfileBug {
    }

    private static class ElasticSearchIndexerBug {
        private static final String CONTENT_FIELD = "content";
        private static final Logger LOG = LoggerFactory.getLogger(ElasticSearchIndexerBug.class);
        private int MAX_LIST_SIZE = 1000;
        private int REPEAT_INTERVAL = 1000;
        private static final long EXPIRE_DATE = 20 * 60 * 1000;
        private static final String POSTS_INDEX = "posts";
        private org.elasticsearch.node.Node node;
        private Client client;
        private Timer timer;
        private List<Entry<PostBug, ProfileBug>> postIndex;

        public ElasticSearchIndexerBug()
        {
            postIndex = Collections.synchronizedList(new ArrayList<Entry<PostBug, ProfileBug>>());
            this.node = NodeBuilder.nodeBuilder().node();
            this.client = this.node.client();
            this.timer = new Timer();
            this.timer.schedule(new IndexerTask(this), REPEAT_INTERVAL, REPEAT_INTERVAL);
        }

        public PostBug addIndex(PostBug post)
        {
            LOG.debug("Indexing new post {} without profile", "api");

            try
            {
                synchronized (postIndex)
                {
                    Map.Entry<PostBug, ProfileBug> entry = new AbstractMap.SimpleEntry<PostBug, ProfileBug>(post, null);
                    postIndex.add(entry);
                }

                if (postIndex.size() > MAX_LIST_SIZE)
                {
                    updatePostIndexes();
                }
            }
            catch (Exception e)
            {
                LOG.error("Could not index tweet ", e);
                return null;
            }

            return post;
        }

        public List<Entry<PostBug, ProfileBug>> search(String query, String source, Long lastCollected, String language)
        {
            LOG.debug("Search in elasticsearch using {} for source {}", query, source);
            LOG.debug("Search in elasticsearch using {} language {}", query, language);

            SearchResponse response = null;
            SearchRequestBuilder request = client.prepareSearch(POSTS_INDEX);

            try
            {
                request.setFilter(FilterBuilders.numericRangeFilter("uploadDate").gte(lastCollected));
                QueryBuilder qb;

                if (language.equals("ALL"))
                {
                    qb = QueryBuilders.queryString(query).analyzer("standard").defaultField(CONTENT_FIELD).defaultOperator(Operator.AND).phraseSlop(0).allowLeadingWildcard(false);
                }
                else
                {
                    qb = QueryBuilders.filteredQuery(QueryBuilders.queryString(query).analyzer("standard").defaultField(CONTENT_FIELD).defaultOperator(Operator.AND).phraseSlop(0).allowLeadingWildcard(false), FilterBuilders.inFilter("language", language.toString().toUpperCase()));
                }

                request.setQuery(qb);
                request.setTypes(source.toString().toUpperCase());
                request.addSort("uploadDate", SortOrder.ASC);
                request.setSize(MAX_LIST_SIZE);
                request.setFrom(0);
                request.setExplain(true);

                LOG.debug("Request {} ", request);

                // Execute get
                response = request.execute().actionGet();
            }
            catch (Exception e)
            {
                LOG.warn("Could not search - {}", e.getMessage());
                e.printStackTrace();
            }

            if (response == null) return new ArrayList<Map.Entry<PostBug, ProfileBug>>(0);

            List<Entry<PostBug, ProfileBug>> result = new ArrayList<Map.Entry<PostBug, ProfileBug>>();

            return result;
        }

        public void updatePostIndexes()
        {
            try
            {
                expireOldData();

                // Bulk index tweets
                BulkRequestBuilder bulkRequest = client.prepareBulk();
                synchronized (postIndex)
                {
                    if (this.postIndex.isEmpty()) { return; }

                    for (Entry<PostBug, ProfileBug> entry : postIndex)
                    {
                        Gson postGson = new Gson();
                        Gson profileGson = new Gson();

                        XContentBuilder content = XContentFactory.jsonBuilder().startObject();
                        content.field(CONTENT_FIELD, entry.getKey().getExtendedContent());
                        content.field("post", postGson.toJson(entry.getKey()));
                        content.field("profile", profileGson.toJson(entry.getValue()));
                        if (entry.getKey().getLanguage() == null)
                        {
                            // language not known
                            content.field("language", "ALL");
                        }
                        else
                        {
                            content.field("language", entry.getKey().getLanguage().toString().toUpperCase());
                        }
                        content.field("uploadDate", entry.getKey().getUploadDate().getTimeInMillis());
                        content.endObject();

                        IndexRequestBuilder request = client.prepareIndex(POSTS_INDEX, "TWITTER");
                        request.setSource(content);

                        bulkRequest.add(request);
                    }
                    postIndex.clear();
                }

                BulkResponse bulkResponse = bulkRequest.execute().actionGet();

                if (bulkResponse.hasFailures())
                {
                    LOG.warn("Couldnt index all posts {}", bulkResponse.buildFailureMessage());
                }
                client.close();
            }
            catch (Exception e)
            {
                LOG.error("Some error occured while trying to update indexes", e);
            }
        }

        public void expireOldData()
        {
            Calendar oldDate = Calendar.getInstance();
            oldDate.setTimeInMillis(oldDate.getTimeInMillis() - EXPIRE_DATE);

            try
            {
                DeleteByQueryRequestBuilder request = client.prepareDeleteByQuery(POSTS_INDEX);
                request.setQuery(QueryBuilders.rangeQuery("uploadDate").lte(oldDate.getTimeInMillis()));
                request.execute().actionGet();
            }
            catch (Exception e)
            {
                LOG.warn("Could NOT expire old tweets {} ", e.getMessage());
            }

        }

        private class IndexerTask
            extends TimerTask {
            private ElasticSearchIndexerBug indexer;

            public IndexerTask(ElasticSearchIndexerBug elasticSearchIndexerBug)
            {
                this.indexer = elasticSearchIndexerBug;
            }

            @Override
            public void run()
            {
                indexer.updatePostIndexes();
            }
        }
    }

}