using FinalFactory.Rendezvous.Contracts;

namespace FinalFactory.Rendezvous.TestClient;

internal sealed class HostServiceFailureBudget
{
    private const int MaximumConsecutiveTransientFailures = 3;
    private int _consecutiveTransientFailures;

    internal bool ShouldStop(
        RendezvousErrorCode error,
        DateTimeOffset leaseExpiresAt,
        DateTimeOffset now)
    {
        if (error == RendezvousErrorCode.None)
        {
            Reset();
            return false;
        }
        if (!IsTransient(error))
        {
            return true;
        }

        _consecutiveTransientFailures++;
        return _consecutiveTransientFailures >= MaximumConsecutiveTransientFailures
            || now >= leaseExpiresAt;
    }

    internal void Reset() => _consecutiveTransientFailures = 0;

    private static bool IsTransient(RendezvousErrorCode error) => error is
        RendezvousErrorCode.RateLimited
        or RendezvousErrorCode.ServiceUnavailable
        or RendezvousErrorCode.InternalError;
}