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;
  
  import static org.apache.asterix.runtime.evaluators.common.ArgumentUtils.NUMERIC_TYPES;
  
  import org.apache.asterix.common.annotations.MissingNullInOutFunction;
  import org.apache.asterix.om.exceptions.ExceptionUtil;
  import org.apache.asterix.om.functions.BuiltinFunctions;
  import org.apache.asterix.om.functions.IFunctionDescriptorFactory;
  import org.apache.asterix.om.types.ATypeTag;
  import org.apache.asterix.om.types.hierachy.ATypeHierarchy;
  import org.apache.asterix.runtime.evaluators.base.AbstractScalarFunctionDynamicDescriptor;
  import org.apache.asterix.runtime.evaluators.functions.utils.RandomHelper;
  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.exceptions.HyracksDataException;
  import org.apache.hyracks.data.std.api.IPointable;
  import org.apache.hyracks.data.std.primitive.VoidPointable;
  import org.apache.hyracks.dataflow.common.data.accessors.IFrameTupleReference;
  
  @MissingNullInOutFunction
  public class RandomWithSeedDescriptor extends AbstractScalarFunctionDynamicDescriptor {
      private static final long serialVersionUID = 1L;
  
      public static final IFunctionDescriptorFactory FACTORY = RandomWithSeedDescriptor::new;
  
      @Override
      public IScalarEvaluatorFactory createEvaluatorFactory(IScalarEvaluatorFactory[] args) {
          return new IScalarEvaluatorFactory() {
              private static final long serialVersionUID = 1L;
  
              @Override
              public IScalarEvaluator createScalarEvaluator(IEvaluatorContext ctx) throws HyracksDataException {
                  return new IScalarEvaluator() {
                      private final IScalarEvaluator eval0 = args[0].createScalarEvaluator(ctx);
                      private final IPointable arg0 = new VoidPointable();
  
                      private final RandomHelper randomHelper = new RandomHelper(true);
  
                      @Override
                      public void evaluate(IFrameTupleReference tuple, IPointable resultPointable)
                              throws HyracksDataException {
                          eval0.evaluate(tuple, arg0);
  
                          if (PointableHelper.checkAndSetMissingOrNull(resultPointable, arg0)) {
                              return;
                          }
  
                          byte[] bytes = arg0.getByteArray();
                          int offset = arg0.getStartOffset();
                          ATypeTag tt = ATypeTag.VALUE_TYPE_MAPPING[bytes[offset]];
                          switch (tt) {
                              case TINYINT:
                              case SMALLINT:
                              case INTEGER:
                              case BIGINT:
                              case FLOAT:
                              case DOUBLE:
                                  double seed =
                                          ATypeHierarchy.getDoubleValue(getIdentifier().getName(), 0, bytes, offset);
                                  randomHelper.setSeed(seed);
                                  randomHelper.nextDouble(resultPointable);
                                  break;
                              default:
                                  ExceptionUtil.warnTypeMismatch(ctx, sourceLoc, getIdentifier(), bytes[offset], 0,
                                          NUMERIC_TYPES);
                                  PointableHelper.setNull(resultPointable);
                                  break;
                          }
                      }
                  };
              }
          };
      }
  
      @Override
      public FunctionIdentifier getIdentifier() {
          return BuiltinFunctions.RANDOM_WITH_SEED;
      }
  }
  