/*
 * 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.graph.streaming.test.operations;

import org.apache.flink.core.fs.FileSystem;
import org.apache.flink.graph.Edge;
import org.apache.flink.graph.streaming.GraphStream;
import org.apache.flink.graph.streaming.SimpleEdgeStream;
import org.apache.flink.graph.streaming.test.GraphStreamTestUtils;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.test.util.AbstractTestBase;
import org.apache.flink.types.NullValue;
import org.junit.Test;

import java.util.List;

public class TestDistinct extends AbstractTestBase {

    @Test
    public void test() throws Exception {

        final String expectedResult = "1,2,12\n" +
                                        "1,3,13\n" +
                                        "2,3,23\n" +
                                        "3,4,34\n" +
                                        "3,5,35\n" +
                                        "4,5,45\n" +
                                        "5,1,51\n";

        final String resultPath = getTempDirPath("result");

        final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();

        List<Edge<Long, Long>> edges = GraphStreamTestUtils.getLongLongEdges();
        edges.addAll(GraphStreamTestUtils.getLongLongEdges());

		GraphStream<Long, NullValue, Long> graph =
				new SimpleEdgeStream<>(env.fromCollection(edges), env);

        graph.distinct().getEdges()
                .writeAsCsv(resultPath, FileSystem.WriteMode.OVERWRITE);

        env.execute();

        compareResultsByLinesInMemory(expectedResult, resultPath);
    }
}
