using GB5Shared.DTO.Framework.Login;
using Microsoft.AspNetCore.SignalR;
using Newtonsoft.Json;

namespace MMSL.Hubs
{
    // Group convention: "schedulingrun:ou:{workOUId}" — OU-scoped broadcast
    public class SchedulingRunHub : Hub<ISchedulingRunClient>
    {
        private readonly ILogger<SchedulingRunHub> _logger;

        public SchedulingRunHub(ILogger<SchedulingRunHub> logger)
        {
            _logger = logger;
        }

        public override async Task OnConnectedAsync()
        {
            var login = GetLoginDTO();
            await Groups.AddToGroupAsync(Context.ConnectionId, HubGroup(login));
            _logger.LogInformation("SchedulingRunHub connected: {ConnectionId} OU {WorkOUId}",
                Context.ConnectionId, login.WorkOUId);
            await base.OnConnectedAsync();
        }

        public override async Task OnDisconnectedAsync(Exception? exception)
        {
            var login = GetLoginDTO();
            await Groups.RemoveFromGroupAsync(Context.ConnectionId, HubGroup(login));
            if (exception is not null)
                _logger.LogWarning(exception, "SchedulingRunHub disconnected with error: {ConnectionId}",
                    Context.ConnectionId);
            await base.OnDisconnectedAsync(exception);
        }

        private LoginDTO GetLoginDTO()
        {
            var httpContext = Context.GetHttpContext()
                ?? throw new InvalidOperationException("Hub invoked outside HTTP context.");
            if (!httpContext.Request.Headers.TryGetValue("Login", out var loginHeader))
                throw new InvalidOperationException("Login header is missing from hub request.");
            return JsonConvert.DeserializeObject<LoginDTO>(loginHeader!)
                ?? throw new InvalidOperationException("Login header could not be deserialized.");
        }

        public static string HubGroup(LoginDTO login) => $"schedulingrun:ou:{login.WorkOUId}";
        public static string HubGroup(int workOUId)   => $"schedulingrun:ou:{workOUId}";
    }
}