package mtas.search.spans;

import java.io.IOException;

import org.apache.lucene.search.TwoPhaseIterator;
import org.apache.lucene.search.spans.SpanCollector;

import mtas.search.spans.util.MtasSpanQuery;
import mtas.search.spans.util.MtasSpans;

/**
 * The Class MtasSpanMatchNoneSpans.
 */
public class MtasSpanMatchNoneSpans extends MtasSpans {

  /** The query. */
  private MtasSpanQuery query;

  /** The current start position. */
  private int currentStartPosition;

  /** The current end position. */
  private int currentEndPosition;

  /** The doc id. */
  private int docId;

  /**
   * Instantiates a new mtas span match none spans.
   *
   * @param query the query
   */
  public MtasSpanMatchNoneSpans(MtasSpanQuery query) {
    currentStartPosition = NO_MORE_POSITIONS;
    currentEndPosition = NO_MORE_POSITIONS;
    docId = -1;
    this.query = query;
  }

  /*
   * (non-Javadoc)
   * 
   * @see org.apache.lucene.search.spans.Spans#nextStartPosition()
   */
  @Override
  public int nextStartPosition() throws IOException {
    return currentStartPosition;
  }

  /*
   * (non-Javadoc)
   * 
   * @see org.apache.lucene.search.spans.Spans#startPosition()
   */
  @Override
  public int startPosition() {
    return currentStartPosition;
  }

  /*
   * (non-Javadoc)
   * 
   * @see org.apache.lucene.search.spans.Spans#endPosition()
   */
  @Override
  public int endPosition() {
    return currentEndPosition;
  }

  /*
   * (non-Javadoc)
   * 
   * @see org.apache.lucene.search.spans.Spans#width()
   */
  @Override
  public int width() {
    return 0;
  }

  /*
   * (non-Javadoc)
   * 
   * @see
   * org.apache.lucene.search.spans.Spans#collect(org.apache.lucene.search.spans
   * .SpanCollector)
   */
  @Override
  public void collect(SpanCollector collector) throws IOException {
    // do nothing
  }

  /*
   * (non-Javadoc)
   * 
   * @see org.apache.lucene.search.DocIdSetIterator#docID()
   */
  @Override
  public int docID() {
    return docId;
  }

  /*
   * (non-Javadoc)
   * 
   * @see org.apache.lucene.search.DocIdSetIterator#nextDoc()
   */
  @Override
  public int nextDoc() throws IOException {
    docId = NO_MORE_DOCS;
    currentStartPosition = NO_MORE_POSITIONS;
    currentEndPosition = NO_MORE_POSITIONS;
    return docId;
  }

  /*
   * (non-Javadoc)
   * 
   * @see org.apache.lucene.search.DocIdSetIterator#advance(int)
   */
  @Override
  public int advance(int target) throws IOException {
    docId = NO_MORE_DOCS;
    currentStartPosition = NO_MORE_POSITIONS;
    currentEndPosition = NO_MORE_POSITIONS;
    return docId;
  }

  /*
   * (non-Javadoc)
   * 
   * @see org.apache.lucene.search.DocIdSetIterator#cost()
   */
  @Override
  public long cost() {
    return 0;
  }

  /*
   * (non-Javadoc)
   * 
   * @see org.apache.lucene.search.spans.Spans#positionsCost()
   */
  @Override
  public float positionsCost() {
    return 0;
  }

  /*
   * (non-Javadoc)
   * 
   * @see mtas.search.spans.util.MtasSpans#asTwoPhaseIterator()
   */
  @Override
  public TwoPhaseIterator asTwoPhaseIterator() {
    if (!query.twoPhaseIteratorAllowed()) {
      return null;
    } else {
      // TODO
      return null;
    }
  }

}