package org.apache.lucene.index;

/**
 * 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.
 */

import org.apache.lucene.analysis.MockAnalyzer;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.MockTokenizer;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.index.IndexWriterConfig.OpenMode;
import org.apache.lucene.util._TestUtil;
import org.apache.lucene.util.English;

import org.apache.lucene.util.LuceneTestCase;

import java.io.File;
import java.util.Random;

public class TestThreadedOptimize extends LuceneTestCase {
  
  private static final Analyzer ANALYZER = new MockAnalyzer(MockTokenizer.SIMPLE, true);

  private final static int NUM_THREADS = 3;
  //private final static int NUM_THREADS = 5;

  private final static int NUM_ITER = 1;
  //private final static int NUM_ITER = 10;

  private final static int NUM_ITER2 = 1;
  //private final static int NUM_ITER2 = 5;

  private boolean failed;

  private void setFailed() {
    failed = true;
  }

  public void runTest(Random random, Directory directory, MergeScheduler merger) throws Exception {

    IndexWriter writer = new IndexWriter(directory, newIndexWriterConfig(random,
        TEST_VERSION_CURRENT, ANALYZER)
        .setOpenMode(OpenMode.CREATE).setMaxBufferedDocs(2).setMergeScheduler(
            merger));

    for(int iter=0;iter<NUM_ITER;iter++) {
      final int iterFinal = iter;

      ((LogMergePolicy) writer.getConfig().getMergePolicy()).setMergeFactor(1000);

      for(int i=0;i<200;i++) {
        Document d = new Document();
        d.add(new Field("id", Integer.toString(i), Field.Store.YES, Field.Index.NOT_ANALYZED));
        d.add(new Field("contents", English.intToEnglish(i), Field.Store.NO, Field.Index.ANALYZED));
        writer.addDocument(d);
      }

      ((LogMergePolicy) writer.getConfig().getMergePolicy()).setMergeFactor(4);
      //writer.setInfoStream(System.out);

      Thread[] threads = new Thread[NUM_THREADS];
      
      for(int i=0;i<NUM_THREADS;i++) {
        final int iFinal = i;
        final IndexWriter writerFinal = writer;
        threads[i] = new Thread() {
          @Override
          public void run() {
            try {
              for(int j=0;j<NUM_ITER2;j++) {
                writerFinal.optimize(false);
                for(int k=0;k<17*(1+iFinal);k++) {
                  Document d = new Document();
                  d.add(new Field("id", iterFinal + "_" + iFinal + "_" + j + "_" + k, Field.Store.YES, Field.Index.NOT_ANALYZED));
                  d.add(new Field("contents", English.intToEnglish(iFinal+k), Field.Store.NO, Field.Index.ANALYZED));
                  writerFinal.addDocument(d);
                }
                for(int k=0;k<9*(1+iFinal);k++)
                  writerFinal.deleteDocuments(new Term("id", iterFinal + "_" + iFinal + "_" + j + "_" + k));
                writerFinal.optimize();
              }
            } catch (Throwable t) {
              setFailed();
              System.out.println(Thread.currentThread().getName() + ": hit exception");
              t.printStackTrace(System.out);
            }
          }
        };
      }

      for(int i=0;i<NUM_THREADS;i++)
        threads[i].start();

      for(int i=0;i<NUM_THREADS;i++)
        threads[i].join();

      assertTrue(!failed);

      final int expectedDocCount = (int) ((1+iter)*(200+8*NUM_ITER2*(NUM_THREADS/2.0)*(1+NUM_THREADS)));

      // System.out.println("TEST: now index=" + writer.segString());

      assertEquals(expectedDocCount, writer.maxDoc());

      writer.close();
      writer = new IndexWriter(directory, newIndexWriterConfig(random,
          TEST_VERSION_CURRENT, ANALYZER).setOpenMode(
          OpenMode.APPEND).setMaxBufferedDocs(2));

      IndexReader reader = IndexReader.open(directory, true);
      assertTrue(reader.isOptimized());
      assertEquals(expectedDocCount, reader.numDocs());
      reader.close();
    }
    writer.close();
  }

  /*
    Run above stress test against RAMDirectory and then
    FSDirectory.
  */
  public void testThreadedOptimize() throws Exception {
    Random random = newRandom();
    Directory directory = newDirectory(random);
    runTest(random, directory, new SerialMergeScheduler());
    runTest(random, directory, new ConcurrentMergeScheduler());
    directory.close();

    File dirName = new File(TEMP_DIR, "luceneTestThreadedOptimize");
    directory = FSDirectory.open(dirName);
    runTest(random, directory, new SerialMergeScheduler());
    runTest(random, directory, new ConcurrentMergeScheduler());
    directory.close();
    _TestUtil.rmDir(dirName);
  }
}