/*
 * Copyright 2009-2013 by The Regents of the University of California
 * Licensed 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 from
 * 
 *     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 edu.uci.ics.hivesterix.runtime.factory.evaluator;

import org.apache.hadoop.hive.ql.plan.UDTFDesc;

import edu.uci.ics.hivesterix.logical.expression.ExpressionTranslator;
import edu.uci.ics.hivesterix.runtime.evaluator.UDTFFunctionEvaluator;
import edu.uci.ics.hivesterix.runtime.jobgen.Schema;
import edu.uci.ics.hyracks.algebricks.common.exceptions.AlgebricksException;
import edu.uci.ics.hyracks.algebricks.core.algebra.base.ILogicalExpression;
import edu.uci.ics.hyracks.algebricks.core.algebra.expressions.IVariableTypeEnvironment;
import edu.uci.ics.hyracks.algebricks.runtime.base.ICopyUnnestingFunction;
import edu.uci.ics.hyracks.algebricks.runtime.base.ICopyUnnestingFunctionFactory;
import edu.uci.ics.hyracks.data.std.api.IDataOutputProvider;

public class UnnestingFunctionFactory implements ICopyUnnestingFunctionFactory {

    private static final long serialVersionUID = 1L;

    private UDTFDesc expr;

    private Schema inputSchema;

    private int[] columns;

    public UnnestingFunctionFactory(ILogicalExpression expression, Schema schema, IVariableTypeEnvironment env)
            throws AlgebricksException {
        try {
            expr = (UDTFDesc) ExpressionTranslator.getHiveExpression(expression, env);
        } catch (Exception e) {
            throw new AlgebricksException(e.getMessage());
        }
        inputSchema = schema;
    }

    @Override
    public ICopyUnnestingFunction createUnnestingFunction(IDataOutputProvider provider) throws AlgebricksException {
        return new UDTFFunctionEvaluator(expr, inputSchema, columns, provider.getDataOutput());
    }

}