package org.apache.lucene.codecs.asserting;

/*
 * 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 java.io.IOException;

import org.apache.lucene.codecs.TermVectorsFormat;
import org.apache.lucene.codecs.TermVectorsReader;
import org.apache.lucene.codecs.TermVectorsWriter;
import org.apache.lucene.codecs.lucene40.Lucene40TermVectorsFormat;
import org.apache.lucene.index.AssertingAtomicReader;
import org.apache.lucene.index.FieldInfos;
import org.apache.lucene.index.Fields;
import org.apache.lucene.index.SegmentInfo;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.IOContext;

/**
 * Just like {@link Lucene40TermVectorsFormat} but with additional asserts.
 */
public class AssertingTermVectorsFormat extends TermVectorsFormat {
  private final TermVectorsFormat in = new Lucene40TermVectorsFormat();

  @Override
  public TermVectorsReader vectorsReader(Directory directory, SegmentInfo segmentInfo, FieldInfos fieldInfos, IOContext context) throws IOException {
    return new AssertingTermVectorsReader(in.vectorsReader(directory, segmentInfo, fieldInfos, context));
  }

  @Override
  public TermVectorsWriter vectorsWriter(Directory directory, SegmentInfo segmentInfo, IOContext context) throws IOException {
    return in.vectorsWriter(directory, segmentInfo, context);
  }
  
  static class AssertingTermVectorsReader extends TermVectorsReader {
    private final TermVectorsReader in;
    
    AssertingTermVectorsReader(TermVectorsReader in) {
      this.in = in;
    }
    
    @Override
    public void close() throws IOException {
      in.close();
    }

    @Override
    public Fields get(int doc) throws IOException {
      Fields fields = in.get(doc);
      return fields == null ? null : new AssertingAtomicReader.AssertingFields(fields);
    }

    @Override
    public TermVectorsReader clone() {
      return new AssertingTermVectorsReader(in.clone());
    }
  }  
}