using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.Web;
using Microsoft.AspNet.SignalR;
using Now.Web.Tickers;

namespace Now.Web.Hubs
{
    [Authorize]
    public class DistributionCenterReceivingHub : Hub
    {
        private static readonly ConcurrentDictionary<string, string> _groupMembers = new ConcurrentDictionary<string, string>();
        private readonly DistributionCenterReceivingTicker _distributionCenterReceivingTicker;
        private readonly static ConnectionMapping<string> _connections = new ConnectionMapping<string>();        

        public DistributionCenterReceivingHub() : this(DistributionCenterReceivingTicker.Instance) { }

        public DistributionCenterReceivingHub(DistributionCenterReceivingTicker distributionCenterReceivingTicker)
        {
            _distributionCenterReceivingTicker = distributionCenterReceivingTicker;
        }

        internal static string[] GetGroups()
        {
            try
            {
                return _groupMembers.Values.GroupBy(g => g).Select(country => country.Key).ToArray();
            }
            catch
            {
                return null;
            }
        }

        public void JoinLocation(string locationCode)
        {
            var country = string.IsNullOrEmpty(locationCode) ? "All" : locationCode;
            if (_groupMembers.ContainsKey(Context.ConnectionId))
            {
                string prevCountry;
                if (_groupMembers.TryGetValue(Context.ConnectionId, out prevCountry) && country != prevCountry)
                {
                    Groups.Remove(Context.ConnectionId, prevCountry);
                    _groupMembers.TryRemove(Context.ConnectionId, out prevCountry);
                }
            }
            Groups.Add(Context.ConnectionId, country);
            _groupMembers.TryAdd(Context.ConnectionId, country);
        }

        public override Task OnConnected()
        {
            string name = Context.User.Identity.Name;
            var lc = Context.QueryString["locationCode"];
            JoinLocation(lc);
            _connections.Add(name, Context.ConnectionId);

            return base.OnConnected();
        }

        public override Task OnDisconnected(bool stopCalled)
        {
            if (Context.User != null)
            {
                string name = Context.User.Identity.Name;
                _connections.Remove(name, Context.ConnectionId);
            }
            string country;
            _groupMembers.TryRemove(Context.ConnectionId, out country);
            return base.OnDisconnected(stopCalled);
        }

        public override Task OnReconnected()
        {
            string name = Context.User.Identity.Name;

            if (!_connections.GetConnections(name).Contains(Context.ConnectionId))
            {
                _connections.Add(name, Context.ConnectionId);
            }

            return base.OnReconnected();
        }
    }
}