taxbaik/TaxBaik.Web/Hubs/NotificationHub.cs

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

namespace TaxBaik.Web.Hubs;

/// <summary>
/// Real-time notification hub for admin dashboard
/// SOLID: Single Responsibility - Only broadcasts change notifications
/// No state management - stateless broadcast pattern
/// </summary>
[Authorize]
public class NotificationHub : Hub
{
    private const string AdminGroup = "admins";

    public override async Task OnConnectedAsync()
    {
        await Groups.AddToGroupAsync(Context.ConnectionId, AdminGroup);
        await base.OnConnectedAsync();
    }

    /// <summary>
    /// Broadcast inquiry status changed to all connected admins
    /// Clients should re-fetch from API to verify
    /// </summary>
    public async Task NotifyInquiryStatusChanged(int inquiryId, string newStatus)
    {
        await Clients.Group(AdminGroup).SendAsync("InquiryStatusChanged", new
        {
            InquiryId = inquiryId,
            Status = newStatus,
            ChangedAt = DateTime.UtcNow
        });
    }

    /// <summary>
    /// Broadcast inquiry submitted (new inquiry created)
    /// </summary>
    public async Task NotifyInquiryCreated(int inquiryId, string name)
    {
        await Clients.Group(AdminGroup).SendAsync("InquiryCreated", new
        {
            InquiryId = inquiryId,
            Name = name,
            CreatedAt = DateTime.UtcNow
        });
    }

    /// <summary>
    /// Broadcast client created
    /// </summary>
    public async Task NotifyClientCreated(int clientId, string name)
    {
        await Clients.Group(AdminGroup).SendAsync("ClientCreated", new
        {
            ClientId = clientId,
            Name = name,
            CreatedAt = DateTime.UtcNow
        });
    }

    /// <summary>
    /// Broadcast announcement published
    /// </summary>
    public async Task NotifyAnnouncementPublished(int announcementId, string title)
    {
        await Clients.Group(AdminGroup).SendAsync("AnnouncementPublished", new
        {
            AnnouncementId = announcementId,
            Title = title,
            PublishedAt = DateTime.UtcNow
        });
    }

    /// <summary>
    /// Broadcast tax filing completed
    /// </summary>
    public async Task NotifyFilingCompleted(int filingId, string filingType)
    {
        await Clients.Group(AdminGroup).SendAsync("FilingCompleted", new
        {
            FilingId = filingId,
            FilingType = filingType,
            CompletedAt = DateTime.UtcNow
        });
    }
}