/*
 * 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.lucene.queries.intervals;

import java.io.IOException;
import java.util.Collection;
import java.util.Collections;
import java.util.Objects;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.search.QueryVisitor;

/** A source returning no matches */
class NoMatchIntervalsSource extends IntervalsSource {
  final String reason;

  NoMatchIntervalsSource(String reason) {
    this.reason = reason;
  }

  @Override
  public IntervalIterator intervals(String field, LeafReaderContext ctx) throws IOException {
    return null;
  }

  @Override
  public IntervalMatchesIterator matches(String field, LeafReaderContext ctx, int doc)
      throws IOException {
    return null;
  }

  @Override
  public void visit(String field, QueryVisitor visitor) {}

  @Override
  public int minExtent() {
    return 0;
  }

  @Override
  public Collection<IntervalsSource> pullUpDisjunctions() {
    return Collections.singleton(this);
  }

  @Override
  public boolean equals(Object o) {
    if (this == o) return true;
    if (o == null || getClass() != o.getClass()) return false;
    NoMatchIntervalsSource that = (NoMatchIntervalsSource) o;
    return Objects.equals(reason, that.reason);
  }

  @Override
  public int hashCode() {
    return Objects.hash(reason);
  }

  @Override
  public String toString() {
    return "NOMATCH(" + reason + ")";
  }
}