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 java.io.IOException;
import java.util.HashMap;
import java.util.Map;

/** This is a DocFieldConsumer that inverts each field,
 *  separately, from a Document, and accepts a
 *  InvertedTermsConsumer to process those terms. */

final class DocInverter extends DocFieldConsumer {

  final InvertedDocConsumer consumer;
  final InvertedDocEndConsumer endConsumer;

  final DocumentsWriterPerThread.DocState docState;

  public DocInverter(DocumentsWriterPerThread.DocState docState, InvertedDocConsumer consumer, InvertedDocEndConsumer endConsumer) {
    this.docState = docState;
    this.consumer = consumer;
    this.endConsumer = endConsumer;
  }

  @Override
  void flush(Map<String, DocFieldConsumerPerField> fieldsToFlush, SegmentWriteState state) throws IOException {

    Map<String, InvertedDocConsumerPerField> childFieldsToFlush = new HashMap<>();
    Map<String, InvertedDocEndConsumerPerField> endChildFieldsToFlush = new HashMap<>();

    for (Map.Entry<String, DocFieldConsumerPerField> fieldToFlush : fieldsToFlush.entrySet()) {
      DocInverterPerField perField = (DocInverterPerField) fieldToFlush.getValue();
      childFieldsToFlush.put(fieldToFlush.getKey(), perField.consumer);
      endChildFieldsToFlush.put(fieldToFlush.getKey(), perField.endConsumer);
    }

    consumer.flush(childFieldsToFlush, state);
    endConsumer.flush(endChildFieldsToFlush, state);
  }

  @Override
  public void startDocument() throws IOException {
    consumer.startDocument();
    endConsumer.startDocument();
  }

  @Override
  public void finishDocument() throws IOException {
    // TODO: allow endConsumer.finishDocument to also return
    // a DocWriter
    endConsumer.finishDocument();
    consumer.finishDocument();
  }

  @Override
  void abort() {
    try {
      consumer.abort();
    } finally {
      endConsumer.abort();
    }
  }

  @Override
  public DocFieldConsumerPerField addField(FieldInfo fi) {
    return new DocInverterPerField(this, fi);
  }
}
