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.binary;
  
  import org.apache.asterix.formats.nontagged.SerializerDeserializerProvider;
  import org.apache.asterix.om.base.AInt64;
  import org.apache.asterix.om.base.AMutableInt64;
  import org.apache.asterix.om.types.ATypeTag;
  import org.apache.asterix.om.types.BuiltinType;
  import org.apache.asterix.runtime.evaluators.functions.PointableHelper;
  import org.apache.hyracks.algebricks.core.algebra.functions.FunctionIdentifier;
  import org.apache.hyracks.algebricks.runtime.base.IScalarEvaluatorFactory;
  import org.apache.hyracks.api.context.IEvaluatorContext;
  import org.apache.hyracks.api.dataflow.value.ISerializerDeserializer;
  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.ByteArrayPointable;
  import org.apache.hyracks.dataflow.common.data.accessors.IFrameTupleReference;
  
  public abstract class AbstractFindBinaryEvaluator extends AbstractBinaryScalarEvaluator {
  
      private static final ATypeTag[] EXPECTED_INPUT_TAG = { ATypeTag.BINARY, ATypeTag.BINARY };
      protected final AMutableInt64 result = new AMutableInt64(-1);
      protected final ByteArrayPointable textPtr = new ByteArrayPointable();
      protected final ByteArrayPointable wordPtr = new ByteArrayPointable();
  
      @SuppressWarnings("unchecked")
      protected ISerializerDeserializer<AInt64> intSerde =
              SerializerDeserializerProvider.INSTANCE.getSerializerDeserializer(BuiltinType.AINT64);
  
      public AbstractFindBinaryEvaluator(IEvaluatorContext context, IScalarEvaluatorFactory[] copyEvaluatorFactories,
              FunctionIdentifier funcId, SourceLocation sourceLoc) throws HyracksDataException {
          super(context, copyEvaluatorFactories, funcId, sourceLoc);
      }
  
      @Override
      public void evaluate(IFrameTupleReference tuple, IPointable resultPointable) throws HyracksDataException {
          resultStorage.reset();
          boolean isReturnNull = false;
  
          for (int i = 0; i < pointables.length; ++i) {
              evaluators[i].evaluate(tuple, pointables[i]);
  
              if (PointableHelper.checkAndSetMissingOrNull(resultPointable, pointables[i])) {
                  if (resultPointable.getByteArray()[0] == ATypeTag.SERIALIZED_MISSING_TYPE_TAG) {
                      return;
                  }
  
                  // null value, but check other arguments for missing first (higher priority)
                  isReturnNull = true;
              }
          }
  
          if (isReturnNull) {
              PointableHelper.setNull(resultPointable);
              return;
          }
  
          int fromOffset = getFromOffset(tuple);
          ATypeTag textTag = ATypeTag.VALUE_TYPE_MAPPING[pointables[0].getByteArray()[pointables[0].getStartOffset()]];
          ATypeTag wordTag = ATypeTag.VALUE_TYPE_MAPPING[pointables[1].getByteArray()[pointables[1].getStartOffset()]];
  
          checkTypeMachingThrowsIfNot(EXPECTED_INPUT_TAG, textTag, wordTag);
          textPtr.set(pointables[0].getByteArray(), pointables[0].getStartOffset() + 1, pointables[0].getLength() - 1);
          wordPtr.set(pointables[1].getByteArray(), pointables[0].getStartOffset() + 1, pointables[1].getLength() - 1);
          int pos = indexOf(textPtr.getByteArray(), textPtr.getContentStartOffset(), textPtr.getContentLength(),
                  wordPtr.getByteArray(), wordPtr.getContentStartOffset(), wordPtr.getContentLength(), fromOffset);
          result.setValue(pos);
          intSerde.serialize(result, dataOutput);
          resultPointable.set(resultStorage);
      }
  
      protected abstract int getFromOffset(IFrameTupleReference tuple) throws HyracksDataException;
  
      // copy from String.indexOf(String)
      private int indexOf(byte[] source, int sourceOffset, int sourceCount, byte[] target, int targetOffset,
              int targetCount, int fromIndex) {
          if (fromIndex >= sourceCount) {
              return targetCount == 0 ? sourceCount : -1;
          }
          int from = fromIndex;
          if (from < 0) {
              from = 0;
          }
          if (targetCount == 0) {
              return from;
          }
  
          byte first = target[targetOffset];
          int max = sourceOffset + (sourceCount - targetCount);
  
          for (int i = sourceOffset + fromIndex; i <= max; i++) {
              /* Look for first character. */
              if (source[i] != first) {
                  continue;
              }
  
              /* Found first character, now look at the rest of v2 */
              int j = i + 1;
              int end = j + targetCount - 1;
              for (int k = targetOffset + 1; j < end && source[j] == target[k]; j++, k++) {
                  ;
              }
              if (j == end) {
                  /* Found whole string. */
                  return i - sourceOffset;
              }
          }
          return -1;
      }
  
  }
  