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.om.typecomputer.impl;
  
  import org.apache.asterix.om.exceptions.TypeMismatchException;
  import org.apache.asterix.om.functions.BuiltinFunctions;
  import org.apache.asterix.om.typecomputer.base.AbstractResultTypeComputer;
  import org.apache.asterix.om.types.ATypeTag;
  import org.apache.asterix.om.types.AUnionType;
  import org.apache.asterix.om.types.AbstractCollectionType;
  import org.apache.asterix.om.types.BuiltinType;
  import org.apache.asterix.om.types.IAType;
  import org.apache.asterix.om.types.hierachy.ATypeHierarchy;
  import org.apache.hyracks.algebricks.common.exceptions.AlgebricksException;
  import org.apache.hyracks.algebricks.core.algebra.base.ILogicalExpression;
  import org.apache.hyracks.algebricks.core.algebra.functions.FunctionIdentifier;
  import org.apache.hyracks.api.exceptions.SourceLocation;
  
  public class NonTaggedGetItemResultType extends AbstractResultTypeComputer {
  
      public static final NonTaggedGetItemResultType INSTANCE = new NonTaggedGetItemResultType();
  
      private NonTaggedGetItemResultType() {
      }
  
      @Override
      protected void checkArgType(FunctionIdentifier funcId, int argIndex, IAType type, SourceLocation sourceLoc)
              throws AlgebricksException {
          ATypeTag actualTypeTag = type.getTypeTag();
          if (argIndex == 0) {
              if (type.getTypeTag() != ATypeTag.MULTISET && type.getTypeTag() != ATypeTag.ARRAY) {
                  throw new TypeMismatchException(sourceLoc, funcId, argIndex, actualTypeTag, ATypeTag.MULTISET,
                          ATypeTag.ARRAY);
              }
          } else {
              if (!ATypeHierarchy.isCompatible(type.getTypeTag(), ATypeTag.INTEGER)) {
                  throw new TypeMismatchException(sourceLoc, funcId, argIndex, actualTypeTag, ATypeTag.INTEGER);
              }
          }
      }
  
      @Override
      protected IAType getResultType(ILogicalExpression expr, IAType... strippedInputTypes) throws AlgebricksException {
          IAType type = strippedInputTypes[0];
          if (type.getTypeTag() == ATypeTag.ANY) {
              return BuiltinType.ANY;
          }
          if (!type.getTypeTag().isListType()) {
              throw new TypeMismatchException(expr.getSourceLocation(), BuiltinFunctions.GET_ITEM, 0, type.getTypeTag(),
                      ATypeTag.MULTISET, ATypeTag.ARRAY);
          }
          IAType itemType = ((AbstractCollectionType) type).getItemType();
          if (itemType.getTypeTag() == ATypeTag.ANY) {
              return itemType;
          }
          // Could have out-of-bound access or null elements.
          return AUnionType.createUnknownableType(itemType);
      }
  
  }
  