/**
 * 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.storm.trident.operation.impl;

import org.apache.storm.trident.operation.BaseOperation;
import org.apache.storm.trident.operation.FlatMapFunction;
import org.apache.storm.trident.operation.Function;
import org.apache.storm.trident.operation.Operation;
import org.apache.storm.trident.operation.TridentCollector;
import org.apache.storm.trident.operation.TridentOperationContext;
import org.apache.storm.trident.tuple.TridentTuple;
import org.apache.storm.tuple.Values;

import java.util.Map;

public class FlatMapFunctionExecutor extends BaseOperation implements Function {
    private final FlatMapFunction function;

    public FlatMapFunctionExecutor(FlatMapFunction function) {
        this.function = function;
    }

    @Override
    public void prepare(Map conf, TridentOperationContext context) {
        // If FlatMapFunction is aware of prepare, let it handle preparation
        if (function instanceof Operation) {
            ((Operation) function).prepare(conf, context);
        } else {
            super.prepare(conf, context);
        }
    }

    @Override
    public void cleanup() {
        // If FlatMapFunction is aware of cleanup, let it handle cleaning up
        if (function instanceof Operation) {
            ((Operation) function).cleanup();
        } else {
            super.cleanup();
        }
    }

    @Override
    public void execute(TridentTuple tuple, TridentCollector collector) {
        for (Values values : function.execute(tuple)) {
            collector.emit(values);
        }
    }
}
