using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.SignalR;

namespace Distribution.Features.Notifications;

/// <summary>
/// Server → client only. The server pushes a "notification" event to each recipient; clients never
/// invoke hub methods. Users are addressed by their id (see <see cref="NotificationUserIdProvider"/>).
/// </summary>
[Authorize]
public class NotificationHub : Hub
{
    public const string Path = "/hubs/notifications";
    public const string ClientEvent = "notification";
}

/// <summary>Maps a SignalR connection to the "UserId" claim that <c>AuthMiddleware</c> puts on the principal.</summary>
public class NotificationUserIdProvider : IUserIdProvider
{
    public string? GetUserId(HubConnectionContext connection) =>
        connection.User?.FindFirst("UserId")?.Value;
}