using Omika.Diagnostics.Queries;
using Omika.Diagnostics.Tests.Fakes;

namespace Omika.Diagnostics.Tests;

/// <summary>
/// Tâche 12 — Traces / opérations récentes : exclusion des NULL (C10), groupement
/// distinct (C11/C13), tri dernière activité DESC (C12) et limite (C14).
/// </summary>
public class DiagnosticRecentCorrelationTests
{
    private static readonly DateTimeOffset From = new(2025, 1, 1, 0, 0, 0, TimeSpan.Zero);

    // ------------------------------------------- C10 : traces récentes : null exclu ----
    [Fact]
    public async Task RecentTraces_ExcludesNullTraceIds()
    {
        var repo = new FakeDiagnosticEventRepository();
        await repo.InsertBatchAsync(new[]
        {
            DiagnosticTestData.Event(Guid.NewGuid(), "A", From.AddMinutes(1), traceId: Guid.NewGuid()),
            DiagnosticTestData.Event(Guid.NewGuid(), "B", From.AddMinutes(2), traceId: null), // exclu
            DiagnosticTestData.Event(Guid.NewGuid(), "C", From.AddMinutes(3), traceId: Guid.NewGuid()),
        });

        IReadOnlyList<DiagnosticRecentCorrelation> result = await repo.GetRecentCorrelationsAsync(
            DiagnosticCorrelationDimension.Trace, From, 10);

        Assert.Equal(2, result.Count);
        Assert.All(result, r => Assert.NotEqual(Guid.Empty, r.CorrelationId));
    }

    // ---------------------------------- C11 : traces récentes : groupement distinct ----
    [Fact]
    public async Task RecentTraces_GroupsDistinctTraceIds()
    {
        Guid traceA = Guid.NewGuid();
        Guid traceB = Guid.NewGuid();
        var repo = new FakeDiagnosticEventRepository();
        await repo.InsertBatchAsync(new[]
        {
            DiagnosticTestData.Event(Guid.NewGuid(), "A", From.AddMinutes(1), traceId: traceA),
            DiagnosticTestData.Event(Guid.NewGuid(), "B", From.AddMinutes(2), traceId: traceA),
            DiagnosticTestData.Event(Guid.NewGuid(), "C", From.AddMinutes(3), traceId: traceB),
        });

        IReadOnlyList<DiagnosticRecentCorrelation> result = await repo.GetRecentCorrelationsAsync(
            DiagnosticCorrelationDimension.Trace, From, 10);

        Assert.Equal(2, result.Count);
        DiagnosticRecentCorrelation groupA = Assert.Single(result, r => r.CorrelationId == traceA);
        Assert.Equal(2, groupA.EventCount);
        Assert.Equal(1, Assert.Single(result, r => r.CorrelationId == traceB).EventCount);
    }

    // ------------------------------ C12 : traces récentes : tri dernière activité DESC ----
    [Fact]
    public async Task RecentTraces_OrdersByLastActivityDescending()
    {
        Guid older = Guid.NewGuid();
        Guid newer = Guid.NewGuid();
        var repo = new FakeDiagnosticEventRepository();
        await repo.InsertBatchAsync(new[]
        {
            DiagnosticTestData.Event(Guid.NewGuid(), "A", From.AddMinutes(1), traceId: older),
            DiagnosticTestData.Event(Guid.NewGuid(), "B", From.AddMinutes(10), traceId: newer),
            DiagnosticTestData.Event(Guid.NewGuid(), "C", From.AddMinutes(2), traceId: older),
        });

        IReadOnlyList<DiagnosticRecentCorrelation> result = await repo.GetRecentCorrelationsAsync(
            DiagnosticCorrelationDimension.Trace, From, 10);

        Assert.Equal(2, result.Count);
        Assert.Equal(newer, result[0].CorrelationId); // dernière activité la plus récente
        Assert.Equal(older, result[1].CorrelationId);
    }

    // ------------------------------- C13 : opérations récentes : distinct correct ----
    [Fact]
    public async Task RecentOperations_GroupsDistinctOperationIds()
    {
        Guid opA = Guid.NewGuid();
        Guid opB = Guid.NewGuid();
        var repo = new FakeDiagnosticEventRepository();
        await repo.InsertBatchAsync(new[]
        {
            DiagnosticTestData.Event(Guid.NewGuid(), "A", From.AddMinutes(1), operationId: opA),
            DiagnosticTestData.Event(Guid.NewGuid(), "B", From.AddMinutes(2), operationId: opB),
            DiagnosticTestData.Event(Guid.NewGuid(), "C", From.AddMinutes(3), operationId: opA),
        });

        IReadOnlyList<DiagnosticRecentCorrelation> result = await repo.GetRecentCorrelationsAsync(
            DiagnosticCorrelationDimension.Operation, From, 10);

        Assert.Equal(2, result.Count);
        Assert.Contains(result, r => r.CorrelationId == opA && r.EventCount == 2);
        Assert.Contains(result, r => r.CorrelationId == opB && r.EventCount == 1);
    }

    // ------------------------------------------------- C14 : limite respectée ----
    [Fact]
    public async Task RecentTraces_RespectsLimit()
    {
        var repo = new FakeDiagnosticEventRepository();
        for (int i = 0; i < 5; i++)
        {
            await repo.InsertBatchAsync(new[]
            {
                DiagnosticTestData.Event(Guid.NewGuid(), $"E{i}", From.AddMinutes(i), traceId: Guid.NewGuid())
            });
        }

        IReadOnlyList<DiagnosticRecentCorrelation> result = await repo.GetRecentCorrelationsAsync(
            DiagnosticCorrelationDimension.Trace, From, 2);

        Assert.Equal(2, result.Count);
    }
}