using Microsoft.AspNetCore.SignalR;
using System.Collections.Concurrent;
using System.Security.Claims;
using Microsoft.AspNetCore.Authorization;

namespace vendorApproverBackend.Hubs
{
    [Authorize] // Add authorization if needed
    public class NotificationHub : Hub
    {
        private static readonly ConcurrentDictionary<long, string> _userConnections = new();

        public override async Task OnConnectedAsync()
        {
            var userId = GetUserIdFromContext();
            if (userId.HasValue)
            {
                _userConnections.AddOrUpdate(userId.Value, Context.ConnectionId, (key, oldValue) => Context.ConnectionId);
                await Groups.AddToGroupAsync(Context.ConnectionId, $"user_{userId}");
                Console.WriteLine($"User {userId} connected with connection {Context.ConnectionId}");
            }
            
            await base.OnConnectedAsync();
        }

        public override async Task OnDisconnectedAsync(Exception exception)
        {
            var userId = GetUserIdFromContext();
            if (userId.HasValue)
            {
                _userConnections.TryRemove(userId.Value, out _);
                await Groups.RemoveFromGroupAsync(Context.ConnectionId, $"user_{userId}");
                Console.WriteLine($"User {userId} disconnected");
            }
            
            await base.OnDisconnectedAsync(exception);
        }

        public async Task JoinUserGroup(long userId)
        {
            await Groups.AddToGroupAsync(Context.ConnectionId, $"user_{userId}");
            Console.WriteLine($"User {userId} joined group user_{userId}");
        }

        public async Task LeaveUserGroup(long userId)
        {
            await Groups.RemoveFromGroupAsync(Context.ConnectionId, $"user_{userId}");
        }

        private long? GetUserIdFromContext()
        {
            if (Context.User?.Identity?.IsAuthenticated == true)
            {
                var userIdClaim = Context.User.FindFirst(ClaimTypes.NameIdentifier) ?? 
                                Context.User.FindFirst("userId") ??
                                Context.User.FindFirst("sub");
                
                if (long.TryParse(userIdClaim?.Value, out long userId))
                {
                    return userId;
                }
            }
            return null;
        }

        public static string GetConnectionIdForUser(long userId)
        {
            _userConnections.TryGetValue(userId, out string connectionId);
            return connectionId;
        }
    }
}