/*
 * 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.accumulo.examples.wikisearch.logic;

import static org.junit.Assert.assertEquals;

import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map.Entry;

import junit.framework.Assert;

import org.apache.accumulo.core.client.BatchWriter;
import org.apache.accumulo.core.client.Connector;
import org.apache.accumulo.core.client.MutationsRejectedException;
import org.apache.accumulo.core.client.Scanner;
import org.apache.accumulo.core.client.mock.MockInstance;
import org.apache.accumulo.core.data.Key;
import org.apache.accumulo.core.data.Mutation;
import org.apache.accumulo.core.data.Range;
import org.apache.accumulo.core.data.Value;
import org.apache.accumulo.core.security.Authorizations;
import org.apache.accumulo.core.util.ContextFactory;
import org.apache.accumulo.examples.wikisearch.ingest.WikipediaConfiguration;
import org.apache.accumulo.examples.wikisearch.ingest.WikipediaIngester;
import org.apache.accumulo.examples.wikisearch.ingest.WikipediaInputFormat.WikipediaInputSplit;
import org.apache.accumulo.examples.wikisearch.ingest.WikipediaMapper;
import org.apache.accumulo.examples.wikisearch.parser.RangeCalculator;
import org.apache.accumulo.examples.wikisearch.reader.AggregatingRecordReader;
import org.apache.accumulo.examples.wikisearch.sample.Document;
import org.apache.accumulo.examples.wikisearch.sample.Field;
import org.apache.accumulo.examples.wikisearch.sample.Results;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.RawLocalFileSystem;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.OutputCommitter;
import org.apache.hadoop.mapreduce.RecordWriter;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.apache.hadoop.mapreduce.lib.input.FileSplit;
import org.apache.hadoop.mapreduce.lib.output.FileOutputCommitter;
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
import org.junit.Before;
import org.junit.Test;

public class TestQueryLogic {
  
  private static final String METADATA_TABLE_NAME = "wikiMetadata";
  
  private static final String TABLE_NAME = "wiki";
  
  private static final String INDEX_TABLE_NAME = "wikiIndex";
  
  private static final String RINDEX_TABLE_NAME = "wikiReverseIndex";
  
  private static final String TABLE_NAMES[] = {METADATA_TABLE_NAME, TABLE_NAME, RINDEX_TABLE_NAME, INDEX_TABLE_NAME};
  
  private class MockAccumuloRecordWriter extends RecordWriter<Text,Mutation> {
    @Override
    public void write(Text key, Mutation value) throws IOException, InterruptedException {
      try {
        writerMap.get(key).addMutation(value);
      } catch (MutationsRejectedException e) {
        throw new IOException("Error adding mutation", e);
      }
    }
    
    @Override
    public void close(TaskAttemptContext context) throws IOException, InterruptedException {
      try {
        for (BatchWriter w : writerMap.values()) {
          w.flush();
          w.close();
        }
      } catch (MutationsRejectedException e) {
        throw new IOException("Error closing Batch Writer", e);
      }
    }
    
  }
  
  private Connector c = null;
  private Configuration conf = new Configuration();
  private HashMap<Text,BatchWriter> writerMap = new HashMap<Text,BatchWriter>();
  private QueryLogic table = null;
  
  @Before
  public void setup() throws Exception {
    
    Logger.getLogger(AbstractQueryLogic.class).setLevel(Level.DEBUG);
    Logger.getLogger(QueryLogic.class).setLevel(Level.DEBUG);
    Logger.getLogger(RangeCalculator.class).setLevel(Level.DEBUG);
    
    conf.set(AggregatingRecordReader.START_TOKEN, "<page>");
    conf.set(AggregatingRecordReader.END_TOKEN, "</page>");
    conf.set(WikipediaConfiguration.TABLE_NAME, TABLE_NAME);
    conf.set(WikipediaConfiguration.NUM_PARTITIONS, "1");
    conf.set(WikipediaConfiguration.NUM_GROUPS, "1");
    
    MockInstance i = new MockInstance();
    c = i.getConnector("root", "");
    WikipediaIngester.createTables(c.tableOperations(), TABLE_NAME, false);
    for (String table : TABLE_NAMES) {
      writerMap.put(new Text(table), c.createBatchWriter(table, 1000L, 1000L, 1));
    }
    
    TaskAttemptContext context = ContextFactory.createTaskAttemptContext(conf);
    
    RawLocalFileSystem fs = new RawLocalFileSystem();
    fs.setConf(conf);
    
    URL url = ClassLoader.getSystemResource("enwiki-20110901-001.xml");
    Assert.assertNotNull(url);
    File data = new File(url.toURI());
    Path tmpFile = new Path(data.getAbsolutePath());
    
    // Setup the Mapper
    WikipediaInputSplit split = new WikipediaInputSplit(new FileSplit(tmpFile, 0, fs.pathToFile(tmpFile).length(), null), 0);
    AggregatingRecordReader rr = new AggregatingRecordReader();
    Path ocPath = new Path(tmpFile, "oc");
    OutputCommitter oc = new FileOutputCommitter(ocPath, context);
    fs.deleteOnExit(ocPath);
    StandaloneStatusReporter sr = new StandaloneStatusReporter();
    rr.initialize(split, context);
    MockAccumuloRecordWriter rw = new MockAccumuloRecordWriter();
    WikipediaMapper mapper = new WikipediaMapper();
    
    // Load data into Mock Accumulo
    Mapper<LongWritable,Text,Text,Mutation>.Context con = ContextFactory.createMapContext(mapper, context, rr, rw, oc, sr, split);
    mapper.run(con);
    
    // Flush and close record writers.
    rw.close(context);
    
    table = new QueryLogic();
    table.setMetadataTableName(METADATA_TABLE_NAME);
    table.setTableName(TABLE_NAME);
    table.setIndexTableName(INDEX_TABLE_NAME);
    table.setReverseIndexTableName(RINDEX_TABLE_NAME);
    table.setUseReadAheadIterator(false);
    table.setUnevaluatedFields(Collections.singletonList("TEXT"));
  }
  
  void debugQuery(String tableName) throws Exception {
    Scanner s = c.createScanner(tableName, new Authorizations("all"));
    Range r = new Range();
    s.setRange(r);
    for (Entry<Key,Value> entry : s)
      System.out.println(entry.getKey().toString() + " " + entry.getValue().toString());
  }
  
  @Test
  public void testTitle() throws Exception {
    Logger.getLogger(AbstractQueryLogic.class).setLevel(Level.OFF);
    Logger.getLogger(RangeCalculator.class).setLevel(Level.OFF);
    List<String> auths = new ArrayList<String>();
    auths.add("enwiki");
    
    Results results = table.runQuery(c, auths, "TITLE == 'asphalt' or TITLE == 'abacus' or TITLE == 'acid' or TITLE == 'acronym'", null, null, null);
    List<Document> docs = results.getResults();
    assertEquals(4, docs.size());
    
    results = table.runQuery(c, auths, "TEXT == 'abacus'", null, null, null);
    docs = results.getResults();
    assertEquals(1, docs.size());
    for (Document doc : docs) {
      System.out.println("id: " + doc.getId());
      for (Field field : doc.getFields())
        System.out.println(field.getFieldName() + " -> " + field.getFieldValue());
    }
  }
  
}