OpenTripPlanner/application/src/test/java/org/opentripplanner/model/plan/paging/PagingSearchWindowAdjusterTest.java

package org.opentripplanner.model.plan.paging;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.opentripplanner.utils.time.DurationUtils.duration;

import java.time.Duration;
import java.time.Instant;
import java.util.ArrayList;
import java.util.List;
import org.junit.jupiter.api.Test;

class PagingSearchWindowAdjusterTest {

  private static final boolean CROP_TAIL = true;
  private static final boolean CROP_HEAD = false;

  private static final Duration D0_s = Duration.ZERO;
  private static final Duration D10_m = duration("10m");
  private static final Duration D30_m = duration("30m");
  private static final Duration D50_m = duration("50m");
  private static final Duration D1_h = duration("1h");
  private static final Duration D1_h_10_m = duration("1h10m");
  private static final Duration D1_h_20_m = duration("1h20m");
  private static final Duration D2_h = duration("2h");
  private static final Duration D4_h = duration("4h");
  private static final Duration D5_h = duration("5h");
  private static final Duration D1_d = duration("1d");
  private static final List<Duration> LIST_OF_DURATIONS = List.of(D5_h, D1_h_20_m, D30_m, D10_m);

  private final Instant time = Instant.parse("2022-01-15T12:00:00Z");

  private final PagingSearchWindowAdjuster subject = new PagingSearchWindowAdjuster(
    D10_m,
    D1_d,
    LIST_OF_DURATIONS
  );

  @Test
  void decreaseSearchWindow() {
    assertEquals(
      D1_h_10_m,
      subject.decreaseSearchWindow(D2_h, time, time.plus(D1_h_10_m), CROP_TAIL)
    );
    assertEquals(D50_m, subject.decreaseSearchWindow(D2_h, time, time.plus(D1_h_10_m), CROP_HEAD));

    assertEquals(D4_h, subject.decreaseSearchWindow(D5_h, time, time.plus(D4_h), CROP_TAIL));
    assertEquals(D1_h, subject.decreaseSearchWindow(D5_h, time, time.plus(D4_h), CROP_HEAD));
  }

  @Test
  void keepSearchWindow() {
    assertEquals(D30_m, subject.increaseOrKeepSearchWindow(D30_m, 5, 5));
    assertEquals(D30_m, subject.increaseOrKeepSearchWindow(D30_m, 1, 1));
    assertEquals(D30_m, subject.increaseOrKeepSearchWindow(D30_m, 1, 3));
  }

  @Test
  void increaseSearchWindow() {
    var expectedList = new ArrayList<>(LIST_OF_DURATIONS);
    expectedList.add(D0_s);

    for (int n = 0; n < expectedList.size(); ++n) {
      var expected = expectedList.get(n);
      assertEquals(expected, subject.increaseOrKeepSearchWindow(D0_s, 20, n), "n=" + n);
      assertEquals(
        expected.plus(D30_m),
        subject.increaseOrKeepSearchWindow(D30_m, 20, n),
        "n=" + n
      );
    }
  }

  @Test
  void normalizeSearchWindow() {
    var cases = List.of(
      // Smallest searchWindow allowed is 10 min
      new TestCase(10, -100),
      new TestCase(10, 0),
      new TestCase(10, 10),
      // sw <= 4h, the round up to closest 10 min
      new TestCase(20, 11),
      new TestCase(230, 230),
      new TestCase(240, 231),
      new TestCase(240, 240),
      // sw > 4h, the round up to the closest 30 min
      new TestCase(270, 241),
      new TestCase(300, 300),
      new TestCase(330, 301),
      // Max is 24 hours
      new TestCase(24 * 60, 24 * 60),
      new TestCase(24 * 60, 99_999_999)
    );

    for (TestCase tc : cases) {
      assertEquals(
        Duration.ofMinutes(tc.expectedMinutes()),
        subject.normalizeSearchWindow(tc.inputMinutes() * 60),
        "[exp nSeconds, input nSeconds]: " + tc
      );
    }
  }

  @Test
  void ceiling() {
    assertEquals(-1, PagingSearchWindowAdjuster.ceiling(-1, 1));
    assertEquals(0, PagingSearchWindowAdjuster.ceiling(0, 1));
    assertEquals(1, PagingSearchWindowAdjuster.ceiling(1, 1));

    assertEquals(-2, PagingSearchWindowAdjuster.ceiling(-2, 2));
    assertEquals(0, PagingSearchWindowAdjuster.ceiling(-1, 2));
    assertEquals(0, PagingSearchWindowAdjuster.ceiling(0, 2));
    assertEquals(2, PagingSearchWindowAdjuster.ceiling(2, 2));
    assertEquals(4, PagingSearchWindowAdjuster.ceiling(3, 2));

    assertEquals(-3, PagingSearchWindowAdjuster.ceiling(-3, 3));
    assertEquals(0, PagingSearchWindowAdjuster.ceiling(-2, 3));
    assertEquals(0, PagingSearchWindowAdjuster.ceiling(0, 3));
    assertEquals(3, PagingSearchWindowAdjuster.ceiling(3, 3));
    assertEquals(6, PagingSearchWindowAdjuster.ceiling(4, 3));
  }

  private record TestCase(int expectedMinutes, int inputMinutes) {}
}