/*
 * 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.flink.optimizer.custompartition;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;

import org.apache.flink.api.common.Plan;
import org.apache.flink.api.common.functions.Partitioner;
import org.apache.flink.api.java.DataSet;
import org.apache.flink.api.java.ExecutionEnvironment;
import org.apache.flink.api.java.io.DiscardingOutputFormat;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.api.java.tuple.Tuple3;
import org.apache.flink.optimizer.plan.DualInputPlanNode;
import org.apache.flink.optimizer.plan.OptimizedPlan;
import org.apache.flink.optimizer.plan.SingleInputPlanNode;
import org.apache.flink.optimizer.plan.SinkPlanNode;
import org.apache.flink.optimizer.testfunctions.IdentityGroupReducerCombinable;
import org.apache.flink.optimizer.util.CompilerTestBase;
import org.apache.flink.runtime.operators.shipping.ShipStrategyType;
import org.junit.Test;

@SuppressWarnings({"serial", "unchecked"})
public class CustomPartitioningGlobalOptimizationTest extends CompilerTestBase {

	@Test
	public void testJoinReduceCombination() {
		try {
			final Partitioner<Long> partitioner = new TestPartitionerLong();
			
			ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();
			
			DataSet<Tuple2<Long, Long>> input1 = env.fromElements(new Tuple2<Long, Long>(0L, 0L));
			DataSet<Tuple3<Long, Long, Long>> input2 = env.fromElements(new Tuple3<Long, Long, Long>(0L, 0L, 0L));

			DataSet<Tuple3<Long, Long, Long>> joined = input1.join(input2)
				.where(1).equalTo(0)
				.projectFirst(0, 1)
				.<Tuple3<Long, Long, Long>>projectSecond(2)
				.withPartitioner(partitioner);

			joined.groupBy(1).withPartitioner(partitioner)
					.reduceGroup(new IdentityGroupReducerCombinable<Tuple3<Long,Long,Long>>())
				.output(new DiscardingOutputFormat<Tuple3<Long, Long, Long>>());

			Plan p = env.createProgramPlan();
			OptimizedPlan op = compileNoStats(p);
			
			SinkPlanNode sink = op.getDataSinks().iterator().next();
			SingleInputPlanNode reducer = (SingleInputPlanNode) sink.getInput().getSource();
			
			assertTrue("Reduce is not chained, property reuse does not happen", 
					reducer.getInput().getSource() instanceof DualInputPlanNode);
			
			DualInputPlanNode join = (DualInputPlanNode) reducer.getInput().getSource();
			
			assertEquals(ShipStrategyType.PARTITION_CUSTOM, join.getInput1().getShipStrategy());
			assertEquals(ShipStrategyType.PARTITION_CUSTOM, join.getInput2().getShipStrategy());
			assertEquals(partitioner, join.getInput1().getPartitioner());
			assertEquals(partitioner, join.getInput2().getPartitioner());
			
			assertEquals(ShipStrategyType.FORWARD, reducer.getInput().getShipStrategy());
		}
		catch (Exception e) {
			e.printStackTrace();
			fail(e.getMessage());
		}
	}
	
	// --------------------------------------------------------------------------------------------
	
	private static class TestPartitionerLong implements Partitioner<Long> {
		@Override
		public int partition(Long key, int numPartitions) {
			return 0;
		}
	}
}