/*
 * 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.beam.runners.core;

import static org.hamcrest.Matchers.equalTo;
import static org.junit.Assert.assertThat;

import org.apache.beam.sdk.transforms.windowing.BoundedWindow;
import org.apache.beam.sdk.transforms.windowing.FixedWindows;
import org.apache.beam.sdk.transforms.windowing.GlobalWindow;
import org.apache.beam.sdk.transforms.windowing.IntervalWindow;
import org.apache.beam.sdk.values.WindowingStrategy;
import org.hamcrest.Matchers;
import org.joda.time.Duration;
import org.joda.time.Instant;
import org.joda.time.ReadableInstant;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/**
 * Tests for {@link LateDataUtils}.
 */
@RunWith(JUnit4.class)
public class LateDataUtilsTest {
  @Test
  public void beforeEndOfGlobalWindowSame() {
    FixedWindows windowFn = FixedWindows.of(Duration.standardMinutes(5));
    Duration allowedLateness = Duration.standardMinutes(2);
    WindowingStrategy<?, ?> strategy =
        WindowingStrategy.globalDefault()
            .withWindowFn(windowFn)
            .withAllowedLateness(allowedLateness);

    IntervalWindow window = windowFn.assignWindow(new Instant(10));
    assertThat(
        LateDataUtils.garbageCollectionTime(window, strategy),
        equalTo(window.maxTimestamp().plus(allowedLateness)));
  }

  @Test
  public void garbageCollectionTimeAfterEndOfGlobalWindow() {
    FixedWindows windowFn = FixedWindows.of(Duration.standardMinutes(5));
    WindowingStrategy<?, ?> strategy =
        WindowingStrategy.globalDefault()
            .withWindowFn(windowFn);

    IntervalWindow window = windowFn.assignWindow(new Instant(BoundedWindow.TIMESTAMP_MAX_VALUE));
    assertThat(
        window.maxTimestamp(),
        Matchers.<ReadableInstant>greaterThan(GlobalWindow.INSTANCE.maxTimestamp()));
    assertThat(
        LateDataUtils.garbageCollectionTime(window, strategy),
        equalTo(GlobalWindow.INSTANCE.maxTimestamp()));
  }

  @Test
  public void garbageCollectionTimeAfterEndOfGlobalWindowWithLateness() {
    FixedWindows windowFn = FixedWindows.of(Duration.standardMinutes(5));
    Duration allowedLateness = Duration.millis(Long.MAX_VALUE);
    WindowingStrategy<?, ?> strategy =
        WindowingStrategy.globalDefault()
            .withWindowFn(windowFn)
            .withAllowedLateness(allowedLateness);

    IntervalWindow window = windowFn.assignWindow(new Instant(-100));
    assertThat(
        window.maxTimestamp().plus(allowedLateness),
        Matchers.<ReadableInstant>greaterThan(GlobalWindow.INSTANCE.maxTimestamp()));
    assertThat(
        LateDataUtils.garbageCollectionTime(window, strategy),
        equalTo(GlobalWindow.INSTANCE.maxTimestamp()));
  }
}