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.external.library;
  
  import org.apache.asterix.common.api.IApplicationContext;
  import org.apache.asterix.common.config.CompilerProperties;
  import org.apache.asterix.common.exceptions.AsterixException;
  import org.apache.asterix.common.exceptions.ErrorCode;
  import org.apache.asterix.om.functions.IExternalFunctionDescriptor;
  import org.apache.asterix.om.functions.IExternalFunctionInfo;
  import org.apache.asterix.runtime.functions.FunctionTypeInferers;
  import org.apache.hyracks.algebricks.common.exceptions.AlgebricksException;
  import org.apache.hyracks.algebricks.core.algebra.expressions.AbstractFunctionCallExpression;
  import org.apache.hyracks.algebricks.core.algebra.expressions.IVariableTypeEnvironment;
  import org.apache.hyracks.algebricks.core.jobgen.impl.JobGenContext;
  
  public class ExternalFunctionDescriptorProvider {
  
      public static IExternalFunctionDescriptor resolveExternalFunction(AbstractFunctionCallExpression expr,
              IVariableTypeEnvironment inputTypeEnv, JobGenContext context) throws AlgebricksException {
          IExternalFunctionDescriptor fd = getExternalFunctionDescriptor((IExternalFunctionInfo) expr.getFunctionInfo());
          CompilerProperties props = ((IApplicationContext) context.getAppContext()).getCompilerProperties();
          FunctionTypeInferers.SET_ARGUMENTS_TYPE.infer(expr, fd, inputTypeEnv, props);
          fd.setSourceLocation(expr.getSourceLocation());
          return fd;
      }
  
      private static IExternalFunctionDescriptor getExternalFunctionDescriptor(IExternalFunctionInfo finfo)
              throws AlgebricksException {
          switch (finfo.getKind()) {
              case SCALAR:
                  return new ExternalScalarFunctionDescriptor(finfo);
              case AGGREGATE:
              case UNNEST:
                  throw new AsterixException(ErrorCode.LIBRARY_EXTERNAL_FUNCTION_UNSUPPORTED_KIND, finfo.getKind());
              default:
                  throw new AsterixException(ErrorCode.LIBRARY_EXTERNAL_FUNCTION_UNKNOWN_KIND, finfo.getKind());
          }
      }
  }
  