using System.Threading;
using Svrnty.CQRS.Events.Abstractions.EventStore;
using System.Threading.Tasks;

namespace Svrnty.CQRS.Events.Abstractions.Notifications;

/// <summary>
/// Service for notifying active subscribers about new events in real-time.
/// Implementations handle the transport layer (gRPC, SignalR, etc.).
/// </summary>
public interface IEventNotifier
{
    /// <summary>
    /// Notify all active subscribers about a new event.
    /// This is called after an event is stored to push it to connected clients.
    /// </summary>
    /// <param name="event">The event that was emitted.</param>
    /// <param name="sequence">The sequence number assigned to this event.</param>
    /// <param name="cancellationToken">Cancellation token.</param>
    Task NotifyAsync(ICorrelatedEvent @event, long sequence, CancellationToken cancellationToken = default);
}