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.lang.sqlpp.visitor;
  
  import org.apache.asterix.common.exceptions.CompilationException;
  import org.apache.asterix.common.exceptions.ErrorCode;
  import org.apache.asterix.common.functions.FunctionSignature;
  import org.apache.asterix.lang.common.base.IVisitorExtension;
  import org.apache.asterix.lang.common.expression.CallExpr;
  import org.apache.asterix.lang.sqlpp.visitor.base.AbstractSqlppContainsExpressionVisitor;
  import org.apache.asterix.metadata.declared.MetadataProvider;
  import org.apache.asterix.metadata.entities.Function;
  import org.apache.asterix.om.functions.BuiltinFunctions;
  import org.apache.hyracks.algebricks.common.exceptions.AlgebricksException;
  import org.apache.hyracks.algebricks.core.algebra.functions.IFunctionInfo;
  
  /**
   * Checks whether given expression is non-functional (i.e. whether it calls a non-functional function)
   */
  public final class CheckNonFunctionalExpressionVisitor extends AbstractSqlppContainsExpressionVisitor<Void> {
  
      private final MetadataProvider metadataProvider;
  
      public CheckNonFunctionalExpressionVisitor(MetadataProvider metadataProvider) {
          this.metadataProvider = metadataProvider;
      }
  
      @Override
      public Boolean visit(CallExpr callExpr, Void arg) throws CompilationException {
          FunctionSignature fs = callExpr.getFunctionSignature();
          IFunctionInfo finfo = BuiltinFunctions.getBuiltinFunctionInfo(fs.createFunctionIdentifier());
          if (finfo != null) {
              if (!finfo.isFunctional()) {
                  return true;
              }
          } else {
              Function function;
              try {
                  function = metadataProvider.lookupUserDefinedFunction(fs);
              } catch (AlgebricksException e) {
                  throw new CompilationException(ErrorCode.METADATA_ERROR, e, callExpr.getSourceLocation(), e.toString());
              }
              if (function == null || function.getDeterministic() == null) {
                  // fail if function not found because all functions must have been resolved at this point
                  // fail if function does not define deterministic property (because it's a SQL++ function
                  // and they were supposed to be inlined at this point)
                  throw new CompilationException(ErrorCode.COMPILATION_ILLEGAL_STATE, callExpr.getSourceLocation(), fs);
              }
              if (!function.getDeterministic()) {
                  return true;
              }
          }
          return super.visit(callExpr, arg);
      }
  
      @Override
      public Boolean visit(IVisitorExtension ve, Void arg) throws CompilationException {
          return ve.checkNonFunctionalDispatch(this);
      }
  }
  