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.typecomputer.base.AbstractResultTypeComputer;
  import org.apache.asterix.om.types.AOrderedListType;
  import org.apache.asterix.om.types.ATypeTag;
  import org.apache.asterix.om.types.BuiltinType;
  import org.apache.asterix.om.types.IAType;
  import org.apache.hyracks.algebricks.common.exceptions.AlgebricksException;
  import org.apache.hyracks.algebricks.core.algebra.base.ILogicalExpression;
  
  /**
   * This type computer functions based on 2 arguments, the {@code inputType} and the {@code outputType}. It checks that
   * all the input types conform to the provided {@code inputType}, and if so, it returns the {@code outputType},
   * otherwise null type is returned.
   */
  public class UniformInputTypeComputer extends AbstractResultTypeComputer {
  
      public static final UniformInputTypeComputer STRING_STRING_INSTANCE =
              new UniformInputTypeComputer(BuiltinType.ASTRING, BuiltinType.ASTRING);
      public static final UniformInputTypeComputer STRING_BOOLEAN_INSTANCE =
              new UniformInputTypeComputer(BuiltinType.ASTRING, BuiltinType.ABOOLEAN);
      public static final UniformInputTypeComputer STRING_INT32_INSTANCE =
              new UniformInputTypeComputer(BuiltinType.ASTRING, BuiltinType.AINT32);
      public static final UniformInputTypeComputer STRING_INT64_INSTANCE =
              new UniformInputTypeComputer(BuiltinType.ASTRING, BuiltinType.AINT64);
      public static final UniformInputTypeComputer STRING_STRING_LIST_INSTANCE = new UniformInputTypeComputer(
              BuiltinType.ASTRING, new AOrderedListType(BuiltinType.ASTRING, BuiltinType.ASTRING.getTypeName()));
      public static final UniformInputTypeComputer STRING_INT64_LIST_INSTANCE = new UniformInputTypeComputer(
              BuiltinType.ASTRING, new AOrderedListType(BuiltinType.AINT64, BuiltinType.AINT64.getTypeName()));
  
      private final IAType inputType;
      private final IAType outputType;
  
      private UniformInputTypeComputer(IAType inputType, IAType outputType) {
          this.inputType = inputType;
          this.outputType = outputType;
      }
  
      @Override
      public IAType getResultType(ILogicalExpression expr, IAType... strippedInputTypes) throws AlgebricksException {
          // all args are expected to be of type inputType
          for (IAType actualType : strippedInputTypes) {
              if (actualType.getTypeTag() != inputType.getTypeTag() && actualType.getTypeTag() != ATypeTag.ANY) {
                  return BuiltinType.ANULL;
              }
          }
  
          return outputType;
      }
  }
  