content: package org.apache.solr.search.function;
  /**
   * 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.solr.search.SolrIndexReader;
  import org.apache.lucene.index.IndexReader;
  
  import java.io.IOException;
  import java.util.Map;
  
  /**
   * A value source that wraps another and ensures that the top level reader
   * is used.  This is useful for value sources like ord() who's value depend
   * on all those around it.
   */
  public class TopValueSource extends ValueSource {
    private final ValueSource vs;
  
    public TopValueSource(ValueSource vs) {
      this.vs = vs;
    }
  
    public ValueSource getValueSource() {
      return vs;
    }
  
    @Override
    public String description() {
      return "top(" + vs.description() + ')';
    }
  
    @Override
    public DocValues getValues(Map context, IndexReader reader) throws IOException {
      int offset = 0;
      IndexReader topReader = reader;
      if (topReader instanceof SolrIndexReader) {
        SolrIndexReader r = (SolrIndexReader)topReader;
        while (r.getParent() != null) {
          offset += r.getBase();
          r = r.getParent();
        }
        topReader = r;
      }
      final int off = offset;
      final DocValues vals = vs.getValues(context, topReader);
      if (topReader == reader) return vals;
  
      return new DocValues() {
        @Override
        public float floatVal(int doc) {
          return vals.floatVal(doc + off);
        }
  
        @Override
        public int intVal(int doc) {
          return vals.intVal(doc + off);
        }
  
        @Override
        public long longVal(int doc) {
          return vals.longVal(doc + off);
        }
  
        @Override
        public double doubleVal(int doc) {
          return vals.doubleVal(doc + off);
        }
  
        @Override
        public String strVal(int doc) {
          return vals.strVal(doc + off);
        }
  
        @Override
        public String toString(int doc) {
          return vals.strVal(doc + off);
        }
      };
    }
  
    @Override
    public boolean equals(Object o) {
      if (o.getClass() !=  TopValueSource.class) return false;
      TopValueSource other = (TopValueSource)o;
      return vs.equals(other.vs);
    }
  
    @Override
    public int hashCode() {
      int h = vs.hashCode();
      return (h<<1) | (h>>>31);
    }
  
    @Override
    public String toString() {
      return "top("+vs.toString()+')';
    }
  }