MSFS VFR Coach

public void TrackTarget(string metric, double deviation, double tol, double dt)
{
    var acc = GetOrAdd(metric);
    acc.LastDeviation = deviation;
    var inBand = Math.Abs(deviation) <= tol;

    if (!acc.Captured)
    {
        if (!inBand) return; // still rolling in / decelerating toward the target
        acc.Captured = true;
    }

    if (inBand)
    {
        if (acc.PendingSec > 0) CommitPending(acc);
        Commit(acc, deviation, tol, dt);
    }
    else
    {
        acc.PendingSec += dt;
        acc.PendingSumSqDt += deviation * deviation * dt;
        if (Math.Abs(deviation) > acc.PendingMaxAbs) acc.PendingMaxAbs = Math.Abs(deviation);
    }
}

private void Activate()
{
    var refIndex = FindEntryReferenceIndex();
    _entrySample = _armedBuffer[refIndex];
    _turnedDeg = 0;
    _activeSince = _entrySample.SimTimeSec;
    Current = State.Active;
    Started?.Invoke(new ManeuverStarted(def.Id, _entrySample.SimTimeSec));

    // Replay the buffered transition (roll-in, deceleration) through the Active
    // tracking so deviations and turn integration start at the true entry.
    _backfilling = true;
    _prev = _entrySample;
    for (var i = refIndex + 1; i < _armedBuffer.Count && Current == State.Active; i++)
    {
        var sample = _armedBuffer[i];
        var dt = sample.SimTimeSec - _prev.SimTimeSec;
        if (dt <= 0 || dt > MaxPlausibleDtSec)
        {
            _prev = sample;
            continue;
        }
        StepActive(sample);
    }
    _backfilling = false;
    _armedBuffer.Clear();
}

/// <summary>
/// Replays a recorded session through the telemetry bus — deterministically and as
/// fast as consumers accept (no wall-clock pacing; all downstream timing derives
/// from SimTimeSec). This is how scoring regression tests and the debriefing
/// replay work without the sim.
/// </summary>
public sealed class SqliteReplaySource(FlightDatabase db, long sessionId) : ITelemetrySource
{
    public Task RunAsync(TelemetryBus bus, CancellationToken ct)
    {
        foreach (var sample in ReadSamples())
        {
            ct.ThrowIfCancellationRequested();
            bus.Publish(sample);
        }
        bus.Complete();
        return Task.CompletedTask;
    }
}

/// <summary>
/// Builds the frames pushed to the panel. THE exam-mode enforcement point (4.2):
/// gauges, tolerances and hints are stripped here, server-side — a tampered panel
/// cannot show live values in exam mode because it never receives them.
/// </summary>
public static LiveFrame BuildLive(
    string? exerciseId,
    FlightPhase phase,
    IModePolicy mode,
    IReadOnlyList<LiveDeviation> liveDeviations,
    string? hint)
{
    var showLive = mode.ShowLiveGauges;
    return new LiveFrame
    {
        Exercise = exerciseId,
        Phase = phase.ToString().ToUpperInvariant(),
        Mode = mode.Mode.ToString().ToUpperInvariant(),
        AidsLevel = mode.AidsLevel.ToString().ToUpperInvariant(),
        Gauges = showLive && liveDeviations.Count > 0
            ? liveDeviations.ToDictionary(d => d.Metric, d => new GaugeDto(Round(d.Deviation), d.Tol, d.Unit))
            : null,
        Hint = showLive ? hint : null,
    };
}