content: /*
   * 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.asterix.runtime.evaluators.functions.records;
  
  import java.io.DataOutput;
  import java.io.IOException;
  
  import org.apache.asterix.dataflow.data.nontagged.serde.ARecordSerializerDeserializer;
  import org.apache.asterix.formats.nontagged.BinaryComparatorFactoryProvider;
  import org.apache.asterix.formats.nontagged.BinaryHashFunctionFactoryProvider;
  import org.apache.asterix.om.exceptions.ExceptionUtil;
  import org.apache.asterix.om.types.ATypeTag;
  import org.apache.asterix.om.types.EnumDeserializer;
  import org.apache.asterix.om.utils.NonTaggedFormatUtil;
  import org.apache.asterix.runtime.evaluators.functions.PointableHelper;
  import org.apache.hyracks.algebricks.core.algebra.functions.FunctionIdentifier;
  import org.apache.hyracks.algebricks.runtime.base.IScalarEvaluator;
  import org.apache.hyracks.algebricks.runtime.base.IScalarEvaluatorFactory;
  import org.apache.hyracks.api.context.IEvaluatorContext;
  import org.apache.hyracks.api.dataflow.value.IBinaryComparator;
  import org.apache.hyracks.api.dataflow.value.IBinaryHashFunction;
  import org.apache.hyracks.api.exceptions.HyracksDataException;
  import org.apache.hyracks.api.exceptions.SourceLocation;
  import org.apache.hyracks.data.std.api.IPointable;
  import org.apache.hyracks.data.std.primitive.VoidPointable;
  import org.apache.hyracks.data.std.util.ArrayBackedValueStorage;
  import org.apache.hyracks.dataflow.common.data.accessors.IFrameTupleReference;
  
  public class FieldAccessByNameEvalFactory implements IScalarEvaluatorFactory {
  
      private static final long serialVersionUID = 1L;
  
      private final IScalarEvaluatorFactory recordEvalFactory;
      private final IScalarEvaluatorFactory fldNameEvalFactory;
      private final SourceLocation sourceLoc;
      private final FunctionIdentifier funID;
  
      public FieldAccessByNameEvalFactory(IScalarEvaluatorFactory recordEvalFactory,
              IScalarEvaluatorFactory fldNameEvalFactory, SourceLocation sourceLoc, FunctionIdentifier funID) {
          this.recordEvalFactory = recordEvalFactory;
          this.fldNameEvalFactory = fldNameEvalFactory;
          this.sourceLoc = sourceLoc;
          this.funID = funID;
      }
  
      @Override
      public IScalarEvaluator createScalarEvaluator(final IEvaluatorContext ctx) throws HyracksDataException {
          return new IScalarEvaluator() {
  
              private final IBinaryHashFunction fieldNameHashFunction =
                      BinaryHashFunctionFactoryProvider.UTF8STRING_POINTABLE_INSTANCE.createBinaryHashFunction();
              private final IBinaryComparator fieldNameComparator =
                      BinaryComparatorFactoryProvider.UTF8STRING_POINTABLE_INSTANCE.createBinaryComparator();
              private final ArrayBackedValueStorage resultStorage = new ArrayBackedValueStorage();
              private final DataOutput out = resultStorage.getDataOutput();
  
              private final IPointable inputArg0 = new VoidPointable();
              private final IPointable inputArg1 = new VoidPointable();
              private final IScalarEvaluator eval0 = recordEvalFactory.createScalarEvaluator(ctx);
              private final IScalarEvaluator eval1 = fldNameEvalFactory.createScalarEvaluator(ctx);
  
              @Override
              public void evaluate(IFrameTupleReference tuple, IPointable result) throws HyracksDataException {
                  try {
                      resultStorage.reset();
                      eval0.evaluate(tuple, inputArg0);
                      eval1.evaluate(tuple, inputArg1);
  
                      if (PointableHelper.checkAndSetMissingOrNull(result, inputArg0, inputArg1)) {
                          return;
                      }
  
                      byte[] serRecord = inputArg0.getByteArray();
                      int serRecordOffset = inputArg0.getStartOffset();
                      int serRecordLen = inputArg0.getLength();
  
                      if (serRecord[serRecordOffset] != ATypeTag.SERIALIZED_RECORD_TYPE_TAG) {
                          ExceptionUtil.warnTypeMismatch(ctx, sourceLoc, funID, serRecord[serRecordOffset], 0,
                                  ATypeTag.OBJECT);
                          out.writeByte(ATypeTag.SERIALIZED_MISSING_TYPE_TAG);
                          result.set(resultStorage);
                          return;
                      }
                      byte[] serFldName = inputArg1.getByteArray();
                      int serFldNameOffset = inputArg1.getStartOffset();
                      if (serFldName[serFldNameOffset] != ATypeTag.SERIALIZED_STRING_TYPE_TAG) {
                          ExceptionUtil.warnTypeMismatch(ctx, sourceLoc, funID, serFldName[serFldNameOffset], 1,
                                  ATypeTag.STRING);
                          out.writeByte(ATypeTag.SERIALIZED_MISSING_TYPE_TAG);
                          result.set(resultStorage);
                          return;
                      }
                      int fieldValueOffset =
                              ARecordSerializerDeserializer.getFieldOffsetByName(serRecord, serRecordOffset, serRecordLen,
                                      serFldName, serFldNameOffset, fieldNameHashFunction, fieldNameComparator);
                      if (fieldValueOffset < 0) {
                          out.writeByte(ATypeTag.SERIALIZED_MISSING_TYPE_TAG);
                          result.set(resultStorage);
                          return;
                      }
  
                      ATypeTag fieldValueTypeTag =
                              EnumDeserializer.ATYPETAGDESERIALIZER.deserialize(serRecord[fieldValueOffset]);
                      int fieldValueLength = NonTaggedFormatUtil.getFieldValueLength(serRecord, fieldValueOffset,
                              fieldValueTypeTag, true) + 1;
                      result.set(serRecord, fieldValueOffset, fieldValueLength);
                  } catch (IOException e) {
                      throw HyracksDataException.create(e);
                  }
              }
          };
      }
  
      public IScalarEvaluatorFactory getRecordEvalFactory() {
          return recordEvalFactory;
      }
  
      public IScalarEvaluatorFactory getFldNameEvalFactory() {
          return fldNameEvalFactory;
      }
  
      public SourceLocation getSourceLoc() {
          return sourceLoc;
      }
  
      public FunctionIdentifier getFunID() {
          return funID;
      }
  }
  