/*
 * 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
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * 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.streaming.api.operators.co;


import org.apache.flink.streaming.api.TimeDomain;
import org.apache.flink.streaming.api.functions.co.CoProcessFunction;
import org.apache.flink.streaming.api.watermark.Watermark;
import org.apache.flink.streaming.runtime.streamrecord.StreamRecord;
import org.apache.flink.streaming.util.TwoInputStreamOperatorTestHarness;
import org.apache.flink.streaming.util.TestHarnessUtil;
import org.apache.flink.util.Collector;
import org.apache.flink.util.TestLogger;
import org.junit.Test;

import java.util.concurrent.ConcurrentLinkedQueue;

import static org.junit.Assert.assertEquals;

/**
 * Tests {@link CoProcessOperator}.
 */
public class CoProcessOperatorTest extends TestLogger {

	@Test
	public void testTimestampAndWatermarkQuerying() throws Exception {

		CoProcessOperator<Integer, String, String> operator =
				new CoProcessOperator<>(new WatermarkQueryingProcessFunction());

		TwoInputStreamOperatorTestHarness<Integer, String, String> testHarness =
				new TwoInputStreamOperatorTestHarness<>(operator);

		testHarness.setup();
		testHarness.open();

		testHarness.processWatermark1(new Watermark(17));
		testHarness.processWatermark2(new Watermark(17));
		testHarness.processElement1(new StreamRecord<>(5, 12L));

		testHarness.processWatermark1(new Watermark(42));
		testHarness.processWatermark2(new Watermark(42));
		testHarness.processElement2(new StreamRecord<>("6", 13L));

		ConcurrentLinkedQueue<Object> expectedOutput = new ConcurrentLinkedQueue<>();

		expectedOutput.add(new Watermark(17L));
		expectedOutput.add(new StreamRecord<>("5WM:17 TS:12", 12L));
		expectedOutput.add(new Watermark(42L));
		expectedOutput.add(new StreamRecord<>("6WM:42 TS:13", 13L));

		TestHarnessUtil.assertOutputEquals("Output was not correct.", expectedOutput, testHarness.getOutput());

		testHarness.close();
	}

	@Test
	public void testTimestampAndProcessingTimeQuerying() throws Exception {

		CoProcessOperator<Integer, String, String> operator =
				new CoProcessOperator<>(new ProcessingTimeQueryingProcessFunction());

		TwoInputStreamOperatorTestHarness<Integer, String, String> testHarness =
				new TwoInputStreamOperatorTestHarness<>(operator);

		testHarness.setup();
		testHarness.open();

		testHarness.setProcessingTime(17);
		testHarness.processElement1(new StreamRecord<>(5));

		testHarness.setProcessingTime(42);
		testHarness.processElement2(new StreamRecord<>("6"));

		ConcurrentLinkedQueue<Object> expectedOutput = new ConcurrentLinkedQueue<>();

		expectedOutput.add(new StreamRecord<>("5PT:17 TS:null"));
		expectedOutput.add(new StreamRecord<>("6PT:42 TS:null"));

		TestHarnessUtil.assertOutputEquals("Output was not correct.", expectedOutput, testHarness.getOutput());

		testHarness.close();
	}


	private static class WatermarkQueryingProcessFunction extends CoProcessFunction<Integer, String, String> {

		private static final long serialVersionUID = 1L;

		@Override
		public void processElement1(Integer value, Context ctx, Collector<String> out) throws Exception {
			out.collect(value + "WM:" + ctx.timerService().currentWatermark() + " TS:" + ctx.timestamp());
		}

		@Override
		public void processElement2(String value, Context ctx, Collector<String> out) throws Exception {
			out.collect(value + "WM:" + ctx.timerService().currentWatermark() + " TS:" + ctx.timestamp());
		}

		@Override
		public void onTimer(
				long timestamp,
				OnTimerContext ctx,
				Collector<String> out) throws Exception {
		}
	}

	private static class ProcessingTimeQueryingProcessFunction extends CoProcessFunction<Integer, String, String> {

		private static final long serialVersionUID = 1L;

		@Override
		public void processElement1(Integer value, Context ctx, Collector<String> out) throws Exception {
			out.collect(value + "PT:" + ctx.timerService().currentProcessingTime() + " TS:" + ctx.timestamp());
		}

		@Override
		public void processElement2(String value, Context ctx, Collector<String> out) throws Exception {
			out.collect(value + "PT:" + ctx.timerService().currentProcessingTime() + " TS:" + ctx.timestamp());
		}

		@Override
		public void onTimer(
				long timestamp,
				OnTimerContext ctx,
				Collector<String> out) throws Exception {
		}
	}
}