using ZB.MOM.WW.GalaxyRepository;
using ZB.MOM.WW.GalaxyRepository.Grpc;

namespace ZB.MOM.WW.GalaxyRepository.Tests;

/// <summary>
///     GalaxyRepository-001 (scadaproj#41): the per-entry filter memo was unbounded, so a client
///     issuing distinct <c>tag_name_glob</c> values (<c>*</c>, <c>**</c>, ...) retained one full
///     result list per glob until the next Galaxy deploy. The memo must stay capped.
/// </summary>
public sealed class ProjectionMemoBoundTests
{
    private const int DistinctFilters = 500;

    [Fact]
    public void DiscoverHierarchy_memo_is_bounded_under_distinct_client_globs()
    {
        GalaxyHierarchyCacheEntry entry = CreateEntry();

        for (int i = 1; i <= DistinctFilters; i++)
        {
            GalaxyHierarchyProjector.Project(entry, new DiscoverHierarchyRequest { TagNameGlob = new string('*', i) }, null, 0, 1);
        }

        Assert.InRange(GalaxyHierarchyProjector.MemoCount(entry), 1, ProjectionMemo<object>.Capacity);
    }

    [Fact]
    public void BrowseChildren_memo_is_bounded_under_distinct_client_globs()
    {
        GalaxyHierarchyCacheEntry entry = CreateEntry();

        for (int i = 1; i <= DistinctFilters; i++)
        {
            GalaxyBrowseProjector.ProjectChildren(entry, new BrowseChildrenRequest { TagNameGlob = new string('*', i) }, null, 0, 1);
        }

        Assert.InRange(GalaxyBrowseProjector.MemoCount(entry), 1, ProjectionMemo<object>.Capacity);
    }

    [Fact]
    public void Evicted_signature_is_recomputed_with_the_same_answer()
    {
        GalaxyHierarchyCacheEntry entry = CreateEntry();
        DiscoverHierarchyRequest first = new() { TagNameGlob = "Plant.*" };
        GalaxyHierarchyQueryResult before = GalaxyHierarchyProjector.Project(entry, first, null, 0, 10);

        for (int i = 1; i <= DistinctFilters; i++)
        {
            GalaxyHierarchyProjector.Project(entry, new DiscoverHierarchyRequest { TagNameGlob = new string('*', i) }, null, 0, 1);
        }

        GalaxyHierarchyQueryResult after = GalaxyHierarchyProjector.Project(entry, first, null, 0, 10);
        Assert.Equal(before.TotalObjectCount, after.TotalObjectCount);
        Assert.Equal(before.FilterSignature, after.FilterSignature);
        Assert.Equal(before.Objects.Select(o => o.GobjectId), after.Objects.Select(o => o.GobjectId));
    }

    private static GalaxyHierarchyCacheEntry CreateEntry()
    {
        GalaxyObject[] objects =
        [
            new() { GobjectId = 1, ParentGobjectId = 0, IsArea = true, ContainedName = "Plant", BrowseName = "Plant", TagName = "Plant" },
            new() { GobjectId = 2, ParentGobjectId = 1, ContainedName = "Pump", BrowseName = "Pump", TagName = "Plant.Pump" },
            new() { GobjectId = 3, ParentGobjectId = 1, ContainedName = "Valve", BrowseName = "Valve", TagName = "Plant.Valve" },
        ];
        return GalaxyHierarchyCacheEntry.Empty with
        {
            Status = GalaxyCacheStatus.Healthy,
            Sequence = 1,
            LastSuccessAt = DateTimeOffset.UtcNow,
            Objects = objects,
            Index = GalaxyHierarchyIndex.Build(objects),
            ObjectCount = objects.Length,
        };
    }
}