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.common.exceptions.CompilationException;
  import org.apache.asterix.common.exceptions.ErrorCode;
  import org.apache.asterix.om.pointables.base.DefaultOpenFieldType;
  import org.apache.asterix.om.typecomputer.base.AbstractResultTypeComputer;
  import org.apache.asterix.om.types.AUnionType;
  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;
  import org.apache.hyracks.algebricks.core.algebra.expressions.AbstractFunctionCallExpression;
  
  /**
   * Returns a list that is missable/nullable. The list type is taken from one of the input args which is the input list.
   */
  public class AListTypeComputer extends AbstractResultTypeComputer {
      public static final AListTypeComputer INSTANCE_REMOVE = new AListTypeComputer(2, false, false, true);
      public static final AListTypeComputer INSTANCE_PUT = new AListTypeComputer(2, false, true, true);
      public static final AListTypeComputer INSTANCE_PREPEND = new AListTypeComputer(2, true, true, false);
      public static final AListTypeComputer INSTANCE_APPEND = new AListTypeComputer(2, false, true, false);
      public static final AListTypeComputer INSTANCE_INSERT = new AListTypeComputer(3, false, true, false);
      public static final AListTypeComputer INSTANCE_REPLACE = new AListTypeComputer(3, false, true, false);
      public static final AListTypeComputer INSTANCE_SLICE = new AListTypeComputer(-1, false, false, true);
      public static final AListTypeComputer INSTANCE_MOVE = new AListTypeComputer(3, false, false, true);
      public static final AListTypeComputer INSTANCE_SWAP = new AListTypeComputer(3, false, false, true);
  
      private final int minNumArgs;
      private final boolean listIsLast;
      private final boolean makeOpen;
      private final boolean nullInNullOut;
  
      // Use this constructor to skip checking the arguments count
      private AListTypeComputer(int minNumArgs, boolean listIsLast, boolean makeOpen, boolean nullInNullOut) {
          this.minNumArgs = minNumArgs;
          this.listIsLast = listIsLast;
          this.makeOpen = makeOpen;
          this.nullInNullOut = nullInNullOut;
      }
  
      @Override
      protected IAType getResultType(ILogicalExpression expr, IAType... strippedInputTypes) throws AlgebricksException {
          if (minNumArgs > -1 && strippedInputTypes.length < minNumArgs) {
              String functionName = ((AbstractFunctionCallExpression) expr).getFunctionIdentifier().getName();
              throw new CompilationException(ErrorCode.COMPILATION_INVALID_NUM_OF_ARGS, expr.getSourceLocation(),
                      functionName);
          }
          // output type should be the same as as the type tag at [list index]. The output type is nullable/missable
          // since the output could be null due to other invalid arguments or the tag at [list index] itself is not list
          int listIndex = 0;
          if (listIsLast) {
              listIndex = strippedInputTypes.length - 1;
          }
  
          IAType listType = strippedInputTypes[listIndex];
          if (listType.getTypeTag().isListType()) {
              if (makeOpen) {
                  listType = DefaultOpenFieldType.getDefaultOpenFieldType(listType.getTypeTag());
              }
              return AUnionType.createUnknownableType(listType);
          } else {
              return BuiltinType.ANY;
          }
      }
  
      @Override
      protected boolean propagateNullAndMissing() {
          return nullInNullOut;
      }
  }
  