/*
 * 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.api.java.operator;

import java.util.ArrayList;
import java.util.List;

import org.junit.Assert;
import org.apache.flink.api.common.InvalidProgramException;
import org.apache.flink.api.common.typeinfo.BasicTypeInfo;
import org.apache.flink.api.java.aggregation.Aggregations;
import org.apache.flink.api.java.aggregation.UnsupportedAggregationTypeException;
import org.apache.flink.api.java.tuple.Tuple5;
import org.apache.flink.api.java.typeutils.TupleTypeInfo;
import org.junit.Test;
import org.apache.flink.api.java.DataSet;
import org.apache.flink.api.java.ExecutionEnvironment;

public class AggregateOperatorTest {

	// TUPLE DATA
	
	private final List<Tuple5<Integer, Long, String, Long, Integer>> emptyTupleData = 
			new ArrayList<Tuple5<Integer, Long, String, Long, Integer>>();
	
	private final TupleTypeInfo<Tuple5<Integer, Long, String, Long, Integer>> tupleTypeInfo = new 
			TupleTypeInfo<Tuple5<Integer, Long, String, Long, Integer>>(
					BasicTypeInfo.INT_TYPE_INFO,
					BasicTypeInfo.LONG_TYPE_INFO,
					BasicTypeInfo.STRING_TYPE_INFO,
					BasicTypeInfo.LONG_TYPE_INFO,
					BasicTypeInfo.INT_TYPE_INFO
			);
	
	// LONG DATA
	
	private final List<Long> emptyLongData = new ArrayList<Long>();
	
	@Test
	public void testFieldsAggregate() {
		
		final ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();
		DataSet<Tuple5<Integer, Long, String, Long, Integer>> tupleDs = env.fromCollection(emptyTupleData, tupleTypeInfo);

		// should work
		try {
			tupleDs.aggregate(Aggregations.SUM, 1);
		} catch(Exception e) {
			Assert.fail();
		}
		
		// should not work: index out of bounds
		try {
			tupleDs.aggregate(Aggregations.SUM, 10);
			Assert.fail();
		} catch(IllegalArgumentException iae) {
			// we're good here
		} catch(Exception e) {
			Assert.fail();
		}
		
		// should not work: not applied to tuple dataset
		DataSet<Long> longDs = env.fromCollection(emptyLongData, BasicTypeInfo.LONG_TYPE_INFO);
		try {
			longDs.aggregate(Aggregations.MIN, 1);
			Assert.fail();
		} catch(InvalidProgramException uoe) {
			// we're good here
		} catch(Exception e) {
			Assert.fail();
		}
		
	}
	
	@Test
	public void testAggregationTypes() {
		try {
			final ExecutionEnvironment env = ExecutionEnvironment.getExecutionEnvironment();
			DataSet<Tuple5<Integer, Long, String, Long, Integer>> tupleDs = env.fromCollection(emptyTupleData, tupleTypeInfo);
			
			// should work: multiple aggregates
			tupleDs.aggregate(Aggregations.SUM, 0).and(Aggregations.MIN, 4);

			// should work: nested aggregates
			tupleDs.aggregate(Aggregations.MIN, 2).aggregate(Aggregations.SUM, 1);
			
			// should not work: average on string
			try {
				tupleDs.aggregate(Aggregations.SUM, 2);
				Assert.fail();
			} catch (UnsupportedAggregationTypeException iae) {
				// we're good here
			}
		}
		catch(Exception e) {
			System.err.println(e.getMessage());
			e.printStackTrace();
			Assert.fail(e.getMessage());
		}
	}
}