/**
 * 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.solr.search.function;

import org.apache.lucene.index.IndexReader;
import org.apache.solr.search.MutableValue;
import org.apache.solr.search.MutableValueFloat;
import org.apache.solr.search.function.DocValues;
import org.apache.lucene.search.FieldCache;

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

/**
 * Obtains float field values from the {@link org.apache.lucene.search.FieldCache}
 * using <code>getFloats()</code>
 * and makes those values available as other numeric types, casting as needed.
 *
 * @version $Id: FloatFieldSource.java 987690 2010-08-21 02:36:09Z yonik $
 */

public class FloatFieldSource extends FieldCacheSource {
  protected FieldCache.FloatParser parser;

  public FloatFieldSource(String field) {
    this(field, null);
  }

  public FloatFieldSource(String field, FieldCache.FloatParser parser) {
    super(field);
    this.parser = parser;
  }

  public String description() {
    return "float(" + field + ')';
  }

  public DocValues getValues(Map context, IndexReader reader) throws IOException {
    final float[] arr = (parser==null) ?
            cache.getFloats(reader, field) :
            cache.getFloats(reader, field, parser);
    return new DocValues() {
      public float floatVal(int doc) {
        return arr[doc];
      }

      public int intVal(int doc) {
        return (int)arr[doc];
      }

      public long longVal(int doc) {
        return (long)arr[doc];
      }

      public double doubleVal(int doc) {
        return (double)arr[doc];
      }

      public String strVal(int doc) {
        return Float.toString(arr[doc]);
      }

      public String toString(int doc) {
        return description() + '=' + floatVal(doc);
      }

      @Override
      public ValueFiller getValueFiller() {
        return new ValueFiller() {
          private final float[] floatArr = arr;
          private final MutableValueFloat mval = new MutableValueFloat();

          @Override
          public MutableValue getValue() {
            return mval;
          }

          @Override
          public void fillValue(int doc) {
            mval.value = floatArr[doc];
          }
        };
      }

    };
  }

  public boolean equals(Object o) {
    if (o.getClass() !=  FloatFieldSource.class) return false;
    FloatFieldSource other = (FloatFieldSource)o;
    return super.equals(other)
           && this.parser==null ? other.parser==null :
              this.parser.getClass() == other.parser.getClass();
  }

  public int hashCode() {
    int h = parser==null ? Float.class.hashCode() : parser.getClass().hashCode();
    h += super.hashCode();
    return h;
  };

}