package com.ruoyi.system.service.impl;

import static org.junit.jupiter.api.Assertions.assertEquals;

import java.util.Arrays;
import java.util.List;
import org.junit.jupiter.api.Test;

/** 区间完整性序号检查的外部行为测试。 */
class IntervalIntegrityCheckerTest
{
    @Test
    void ignoresDuplicatesAndOutOfOrderSamples()
    {
        assertEquals(List.of(new IntervalIntegrityChecker.Gap(3, 3), new IntervalIntegrityChecker.Gap(5, 5)),
                IntervalIntegrityChecker.gaps(List.of(4L, 1L, 2L, 4L, 6L)));
    }

    @Test
    void treatsEachReceptionIntervalIndependently()
    {
        assertEquals(List.of(), IntervalIntegrityChecker.gaps(List.of(1L, 2L)));
        assertEquals(List.of(), IntervalIntegrityChecker.gaps(List.of(8L, 9L)));
    }

    @Test
    void reportsMultipleOpenGaps()
    {
        assertEquals(List.of(new IntervalIntegrityChecker.Gap(3, 4), new IntervalIntegrityChecker.Gap(7, 8)),
                IntervalIntegrityChecker.gaps(List.of(1L, 2L, 5L, 6L, 9L)));
    }

    @Test
    void doesNotTreatPauseOrHandoverAsAnIntraIntervalGap()
    {
        assertEquals(List.of(), IntervalIntegrityChecker.gaps(List.of(10L, 11L)));
        assertEquals(List.of(), IntervalIntegrityChecker.gaps(List.of(20L, 21L)));
    }

    @Test
    void emptyIntervalHasNoSyntheticSequenceGap()
    {
        assertEquals(List.of(), IntervalIntegrityChecker.gaps(List.of()));
    }

    @Test
    void filtersInvalidSequenceValuesWithoutInventingGaps()
    {
        assertEquals(List.of(), IntervalIntegrityChecker.gaps(Arrays.asList(null, 0L, -1L, 5L)));
    }

    @Test
    void remainsStableAcrossReplayPermutationsAndDuplicates()
    {
        List<IntervalIntegrityChecker.Gap> expected = List.of(
                new IntervalIntegrityChecker.Gap(3, 3), new IntervalIntegrityChecker.Gap(6, 7));
        List<List<Long>> replays = List.of(
                List.of(8L, 1L, 2L, 4L, 5L, 8L),
                List.of(1L, 8L, 5L, 4L, 2L, 5L),
                List.of(2L, 4L, 1L, 8L, 4L, 5L));
        for (List<Long> replay : replays) assertEquals(expected, IntervalIntegrityChecker.gaps(replay));
        assertEquals(expected, IntervalIntegrityChecker.gaps(replays.get(0)));
    }
}