using Discord.API;
using Discord.API.Gateway;
using Discord.Audio;
using Discord.Logging;
using Discord.Net.Converters;
using Discord.Net.Udp;
using Discord.Net.WebSockets;
using Discord.Rest;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Collections.Immutable;
using System.IO;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using GameModel = Discord.API.Game;

namespace Discord.WebSocket
{
    public partial class DiscordSocketClient : BaseDiscordClient, IDiscordClient
    {
        private readonly ConcurrentQueue<ulong> _largeGuilds;
        private readonly JsonSerializer _serializer;
        private readonly SemaphoreSlim _connectionGroupLock;
        private readonly DiscordSocketClient _parentClient;
        private readonly ConcurrentQueue<long> _heartbeatTimes;
        private readonly ConnectionManager _connection;
        private readonly Logger _gatewayLogger;
        private readonly SemaphoreSlim _stateLock;

        private string _sessionId;
        private int _lastSeq;
        private ImmutableDictionary<string, RestVoiceRegion> _voiceRegions;
        private Task _heartbeatTask, _guildDownloadTask;
        private int _unavailableGuilds;
        private long _lastGuildAvailableTime, _lastMessageTime;
        private int _nextAudioId;
        private DateTimeOffset? _statusSince;
        private RestApplication _applicationInfo;
        private ConcurrentHashSet<ulong> _downloadUsersFor;

        /// <summary> Gets the shard of of this client. </summary>
        public int ShardId { get; }
        /// <summary> Gets the current connection state of this client. </summary>
        public ConnectionState ConnectionState { get; private set; }
        /// <summary> Gets the estimated round-trip latency, in milliseconds, to the gateway server. </summary>
        public int Latency { get; private set; }
        internal UserStatus Status { get; private set; } = UserStatus.Online;
        internal Game? Game { get; private set; }

        //From DiscordSocketConfig
        internal int TotalShards { get; private set; }
        internal int MessageCacheSize { get; private set; }
        internal int LargeThreshold { get; private set; }
        internal AudioMode AudioMode { get; private set; }
        internal ClientState State { get; private set; }
        internal UdpSocketProvider UdpSocketProvider { get; private set; }
        internal WebSocketProvider WebSocketProvider { get; private set; }
        internal bool AlwaysDownloadUsers { get; private set; }

        internal new DiscordSocketApiClient ApiClient => base.ApiClient as DiscordSocketApiClient;
        public new SocketSelfUser CurrentUser { get { return base.CurrentUser as SocketSelfUser; } private set { base.CurrentUser = value; } }
        public IReadOnlyCollection<SocketGuild> Guilds => State.Guilds;
        public IReadOnlyCollection<ISocketPrivateChannel> PrivateChannels => State.PrivateChannels;
        public IReadOnlyCollection<SocketDMChannel> DMChannels 
            => State.PrivateChannels.Select(x => x as SocketDMChannel).Where(x => x != null).ToImmutableArray();
        public IReadOnlyCollection<SocketGroupChannel> GroupChannels 
            => State.PrivateChannels.Select(x => x as SocketGroupChannel).Where(x => x != null).ToImmutableArray();
        public IReadOnlyCollection<RestVoiceRegion> VoiceRegions => _voiceRegions.ToReadOnlyCollection();

        /// <summary> Creates a new REST/WebSocket discord client. </summary>
        public DiscordSocketClient() : this(new DiscordSocketConfig()) { }
        /// <summary> Creates a new REST/WebSocket discord client. </summary>
        public DiscordSocketClient(DiscordSocketConfig config) : this(config, CreateApiClient(config), null, null) { }
        internal DiscordSocketClient(DiscordSocketConfig config, SemaphoreSlim groupLock, DiscordSocketClient parentClient) : this(config, CreateApiClient(config), groupLock, parentClient) { }
        private DiscordSocketClient(DiscordSocketConfig config, API.DiscordSocketApiClient client, SemaphoreSlim groupLock, DiscordSocketClient parentClient)
            : base(config, client)
        {
            ShardId = config.ShardId ?? 0;
            TotalShards = config.TotalShards ?? 1;
            MessageCacheSize = config.MessageCacheSize;
            LargeThreshold = config.LargeThreshold;
            AudioMode = config.AudioMode;
            UdpSocketProvider = config.UdpSocketProvider;
            WebSocketProvider = config.WebSocketProvider;
            AlwaysDownloadUsers = config.AlwaysDownloadUsers;
            State = new ClientState(0, 0);
            _downloadUsersFor = new ConcurrentHashSet<ulong>();
            _heartbeatTimes = new ConcurrentQueue<long>();

            _stateLock = new SemaphoreSlim(1, 1);
            _gatewayLogger = LogManager.CreateLogger(ShardId == 0 && TotalShards == 1 ? "Gateway" : $"Shard #{ShardId}");
            _connection = new ConnectionManager(_stateLock, _gatewayLogger, config.ConnectionTimeout, 
                OnConnectingAsync, OnDisconnectingAsync, x => ApiClient.Disconnected += x);
            _connection.Connected += () => _connectedEvent.InvokeAsync();
            _connection.Disconnected += (ex, recon) => _disconnectedEvent.InvokeAsync(ex);
            
            _nextAudioId = 1;
            _connectionGroupLock = groupLock;
            _parentClient = parentClient;

            _serializer = new JsonSerializer { ContractResolver = new DiscordContractResolver() };
            _serializer.Error += (s, e) =>
            {
                _gatewayLogger.WarningAsync("Serializer Error", e.ErrorContext.Error).GetAwaiter().GetResult();
                e.ErrorContext.Handled = true;
            };
            
            ApiClient.SentGatewayMessage += async opCode => await _gatewayLogger.DebugAsync($"Sent {opCode}").ConfigureAwait(false);
            ApiClient.ReceivedGatewayEvent += ProcessMessageAsync;

            LeftGuild += async g => await _gatewayLogger.InfoAsync($"Left {g.Name}").ConfigureAwait(false);
            JoinedGuild += async g => await _gatewayLogger.InfoAsync($"Joined {g.Name}").ConfigureAwait(false);
            GuildAvailable += async g => await _gatewayLogger.VerboseAsync($"Connected to {g.Name}").ConfigureAwait(false);
            GuildUnavailable += async g => await _gatewayLogger.VerboseAsync($"Disconnected from {g.Name}").ConfigureAwait(false);
            LatencyUpdated += async (old, val) => await _gatewayLogger.VerboseAsync($"Latency = {val} ms").ConfigureAwait(false);

            GuildAvailable += g =>
            {
                if (ConnectionState == ConnectionState.Connected && (AlwaysDownloadUsers || _downloadUsersFor.ContainsKey(g.Id)))
                {
                    if (!g.HasAllMembers)
                    {
                        var _ = g.DownloadUsersAsync();
                    }
                }
                return Task.Delay(0);
            };

            _voiceRegions = ImmutableDictionary.Create<string, RestVoiceRegion>();
            _largeGuilds = new ConcurrentQueue<ulong>();
        }
        private static API.DiscordSocketApiClient CreateApiClient(DiscordSocketConfig config)
            => new API.DiscordSocketApiClient(config.RestClientProvider, config.WebSocketProvider, DiscordRestConfig.UserAgent, config.GatewayHost);
        internal override void Dispose(bool disposing)
        {
            if (disposing)
            {
                StopAsync().GetAwaiter().GetResult();
                ApiClient.Dispose();
            }
        }
        
        internal override async Task OnLoginAsync(TokenType tokenType, string token)
        {
            if (_parentClient == null)
            {
                var voiceRegions = await ApiClient.GetVoiceRegionsAsync(new RequestOptions { IgnoreState = true, RetryMode = RetryMode.AlwaysRetry }).ConfigureAwait(false);
                _voiceRegions = voiceRegions.Select(x => RestVoiceRegion.Create(this, x)).ToImmutableDictionary(x => x.Id);
            }
            else
                _voiceRegions = _parentClient._voiceRegions;
        }
        internal override async Task OnLogoutAsync()
        {
            await StopAsync().ConfigureAwait(false);
            _applicationInfo = null;
            _voiceRegions = ImmutableDictionary.Create<string, RestVoiceRegion>();
            _downloadUsersFor.Clear();
        }

        public async Task StartAsync() 
            => await _connection.StartAsync().ConfigureAwait(false);
        public async Task StopAsync() 
            => await _connection.StopAsync().ConfigureAwait(false);
        
        private async Task OnConnectingAsync()
        {
            if (_connectionGroupLock != null)
                await _connectionGroupLock.WaitAsync(_connection.CancelToken).ConfigureAwait(false);
            try
            {
                await _gatewayLogger.DebugAsync("Connecting ApiClient").ConfigureAwait(false);
                await ApiClient.ConnectAsync().ConfigureAwait(false);

                if (_sessionId != null)
                {
                    await _gatewayLogger.DebugAsync("Resuming").ConfigureAwait(false);
                    await ApiClient.SendResumeAsync(_sessionId, _lastSeq).ConfigureAwait(false);
                }
                else
                {
                    await _gatewayLogger.DebugAsync("Identifying").ConfigureAwait(false);
                    await ApiClient.SendIdentifyAsync(shardID: ShardId, totalShards: TotalShards).ConfigureAwait(false);
                }

                //Wait for READY
                await _connection.WaitAsync().ConfigureAwait(false);
                
                await _gatewayLogger.DebugAsync("Sending Status").ConfigureAwait(false);
                await SendStatusAsync().ConfigureAwait(false);

                await ProcessUserDownloadsAsync(_downloadUsersFor.Select(x => GetGuild(x))
                    .Where(x => x != null).ToImmutableArray()).ConfigureAwait(false);
            }
            finally 
            {
                if (_connectionGroupLock != null)
                {
                    await Task.Delay(5000).ConfigureAwait(false);
                    _connectionGroupLock.Release();
                }
            }
        }
        private async Task OnDisconnectingAsync(Exception ex)
        {
            ulong guildId;

            await _gatewayLogger.DebugAsync("Disconnecting ApiClient").ConfigureAwait(false);
            await ApiClient.DisconnectAsync().ConfigureAwait(false);

            //Wait for tasks to complete
            await _gatewayLogger.DebugAsync("Waiting for heartbeater").ConfigureAwait(false);
            var heartbeatTask = _heartbeatTask;
            if (heartbeatTask != null)
                await heartbeatTask.ConfigureAwait(false);
            _heartbeatTask = null;

            long time;
            while (_heartbeatTimes.TryDequeue(out time)) { }
            _lastMessageTime = 0;

            await _gatewayLogger.DebugAsync("Waiting for guild downloader").ConfigureAwait(false);
            var guildDownloadTask = _guildDownloadTask;
            if (guildDownloadTask != null)
                await guildDownloadTask.ConfigureAwait(false);
            _guildDownloadTask = null;

            //Clear large guild queue
            await _gatewayLogger.DebugAsync("Clearing large guild queue").ConfigureAwait(false);
            while (_largeGuilds.TryDequeue(out guildId)) { }

            //Raise virtual GUILD_UNAVAILABLEs
            await _gatewayLogger.DebugAsync("Raising virtual GuildUnavailables").ConfigureAwait(false);
            foreach (var guild in State.Guilds)
            {
                if (guild._available)
                    await _guildUnavailableEvent.InvokeAsync(guild).ConfigureAwait(false);
            }
        }

        /// <inheritdoc />
        public async Task<RestApplication> GetApplicationInfoAsync()
        { 
            return _applicationInfo ?? (_applicationInfo = await ClientHelper.GetApplicationInfoAsync(this));
        }

        /// <inheritdoc />
        public SocketGuild GetGuild(ulong id)
        {
            return State.GetGuild(id);
        }
        /// <inheritdoc />
        public Task<RestGuild> CreateGuildAsync(string name, IVoiceRegion region, Stream jpegIcon = null)
            => ClientHelper.CreateGuildAsync(this, name, region, jpegIcon);

        /// <inheritdoc />
        public SocketChannel GetChannel(ulong id)
        {
            return State.GetChannel(id);
        }

        /// <inheritdoc />
        public Task<IReadOnlyCollection<RestConnection>> GetConnectionsAsync()
            => ClientHelper.GetConnectionsAsync(this);

        /// <inheritdoc />
        public Task<RestInvite> GetInviteAsync(string inviteId)
            => ClientHelper.GetInviteAsync(this, inviteId);

        /// <inheritdoc />
        public SocketUser GetUser(ulong id)
        {
            return State.GetUser(id);
        }
        /// <inheritdoc />
        public SocketUser GetUser(string username, string discriminator)
        {
            return State.Users.Where(x => x.Discriminator == discriminator && x.Username == username).FirstOrDefault();
        }
        internal SocketGlobalUser GetOrCreateUser(ClientState state, Discord.API.User model)
        {
            return state.GetOrAddUser(model.Id, x =>
            {
                var user = SocketGlobalUser.Create(this, state, model);
                user.GlobalUser.AddRef();
                return user;
            });
        }
        internal SocketGlobalUser GetOrCreateSelfUser(ClientState state, Discord.API.User model)
        {
            return state.GetOrAddUser(model.Id, x =>
            {
                var user = SocketGlobalUser.Create(this, state, model);
                user.GlobalUser.AddRef();
                user.Presence = new SocketPresence(UserStatus.Online, null);
                return user;
            });
        }
        internal void RemoveUser(ulong id)
        {
            State.RemoveUser(id);
        }

        /// <inheritdoc />
        public RestVoiceRegion GetVoiceRegion(string id)
        {
            RestVoiceRegion region;
            if (_voiceRegions.TryGetValue(id, out region))
                return region;
            return null;
        }

        /// <summary> Downloads the users list for the provided guilds, if they don't have a complete list. </summary>
        public async Task DownloadUsersAsync(IEnumerable<IGuild> guilds)
        {
            foreach (var guild in guilds)
                _downloadUsersFor.TryAdd(guild.Id);

            if (ConnectionState == ConnectionState.Connected)
            {
                //Race condition leads to guilds being requested twice, probably okay
                await ProcessUserDownloadsAsync(guilds.Select(x => GetGuild(x.Id)).Where(x => x != null)).ConfigureAwait(false);
            }
        }
        private async Task ProcessUserDownloadsAsync(IEnumerable<SocketGuild> guilds)
        {
            var cachedGuilds = guilds.ToImmutableArray();

            const short batchSize = 50;
            ulong[] batchIds = new ulong[Math.Min(batchSize, cachedGuilds.Length)];
            Task[] batchTasks = new Task[batchIds.Length];
            int batchCount = (cachedGuilds.Length + (batchSize - 1)) / batchSize;

            for (int i = 0, k = 0; i < batchCount; i++)
            {
                bool isLast = i == batchCount - 1;
                int count = isLast ? (batchIds.Length - (batchCount - 1) * batchSize) : batchSize;

                for (int j = 0; j < count; j++, k++)
                {
                    var guild = cachedGuilds[k];
                    batchIds[j] = guild.Id;
                    batchTasks[j] = guild.DownloaderPromise;
                }

                await ApiClient.SendRequestMembersAsync(batchIds).ConfigureAwait(false);

                if (isLast && batchCount > 1)
                    await Task.WhenAll(batchTasks.Take(count)).ConfigureAwait(false);
                else
                    await Task.WhenAll(batchTasks).ConfigureAwait(false);
            }
        }

        public async Task SetStatusAsync(UserStatus status)
        {
            Status = status;
            if (status == UserStatus.AFK)
                _statusSince = DateTimeOffset.UtcNow;
            else
                _statusSince = null;
            await SendStatusAsync().ConfigureAwait(false);
        }
        public async Task SetGameAsync(string name, string streamUrl = null, StreamType streamType = StreamType.NotStreaming)
        {
            if (name != null)
                Game = new Game(name, streamUrl, streamType);
            else
                Game = null;
            CurrentUser.Presence = new SocketPresence(Status, Game);
            await SendStatusAsync().ConfigureAwait(false);
        }
        private async Task SendStatusAsync()
        {
            var game = Game;
            var status = Status;
            var statusSince = _statusSince;
            CurrentUser.Presence = new SocketPresence(status, game);

            GameModel gameModel;
            if (game != null)
            {
                gameModel = new API.Game
                {
                    Name = game.Value.Name,
                    StreamType = game.Value.StreamType,
                    StreamUrl = game.Value.StreamUrl
                };
            }
            else
                gameModel = null;

            await ApiClient.SendStatusUpdateAsync(
                status,
                status == UserStatus.AFK,
                statusSince != null ? DateTimeUtils.ToUnixMilliseconds(_statusSince.Value) : (long?)null,
                gameModel).ConfigureAwait(false);
        }

        private async Task ProcessMessageAsync(GatewayOpCode opCode, int? seq, string type, object payload)
        {
            if (seq != null)
                _lastSeq = seq.Value;
            _lastMessageTime = Environment.TickCount;
            
            try
            {
                switch (opCode)
                {
                    case GatewayOpCode.Hello:
                        {
                            await _gatewayLogger.DebugAsync("Received Hello").ConfigureAwait(false);
                            var data = (payload as JToken).ToObject<HelloEvent>(_serializer);

                            _heartbeatTask = RunHeartbeatAsync(data.HeartbeatInterval, _connection.CancelToken);
                        }
                        break;
                    case GatewayOpCode.Heartbeat:
                        {
                            await _gatewayLogger.DebugAsync("Received Heartbeat").ConfigureAwait(false);
                            
                            await ApiClient.SendHeartbeatAsync(_lastSeq).ConfigureAwait(false);
                        }
                        break;
                    case GatewayOpCode.HeartbeatAck:
                        {
                            await _gatewayLogger.DebugAsync("Received HeartbeatAck").ConfigureAwait(false);

                            long time;
                            if (_heartbeatTimes.TryDequeue(out time))
                            {
                                int latency = (int)(Environment.TickCount - time);
                                int before = Latency;
                                Latency = latency;

                                await _latencyUpdatedEvent.InvokeAsync(before, latency).ConfigureAwait(false);
                            }
                        }
                        break;
                    case GatewayOpCode.InvalidSession:
                        {
                            await _gatewayLogger.DebugAsync("Received InvalidSession").ConfigureAwait(false);
                            await _gatewayLogger.WarningAsync("Failed to resume previous session").ConfigureAwait(false);

                            _sessionId = null;
                            _lastSeq = 0;
                            await ApiClient.SendIdentifyAsync(shardID: ShardId, totalShards: TotalShards).ConfigureAwait(false);
                        }
                        break;
                    case GatewayOpCode.Reconnect:
                        {
                            await _gatewayLogger.DebugAsync("Received Reconnect").ConfigureAwait(false);
                            _connection.Error(new Exception("Server requested a reconnect"));
                        }
                        break;
                    case GatewayOpCode.Dispatch:
                        switch (type)
                        {
                            //Connection
                            case "READY":
                                {
                                    try
                                    {
                                        await _gatewayLogger.DebugAsync("Received Dispatch (READY)").ConfigureAwait(false);

                                        var data = (payload as JToken).ToObject<ReadyEvent>(_serializer);
                                        var state = new ClientState(data.Guilds.Length, data.PrivateChannels.Length);

                                        var currentUser = SocketSelfUser.Create(this, state, data.User);
                                        ApiClient.CurrentUserId = currentUser.Id;
                                        int unavailableGuilds = 0;
                                        for (int i = 0; i < data.Guilds.Length; i++)
                                        {
                                            var model = data.Guilds[i];
                                            var guild = AddGuild(model, state);
                                            if (!guild._available || ApiClient.AuthTokenType == TokenType.User)
                                                unavailableGuilds++;
                                            else
                                                await _guildAvailableEvent.InvokeAsync(guild).ConfigureAwait(false);
                                        }
                                        for (int i = 0; i < data.PrivateChannels.Length; i++)
                                            AddPrivateChannel(data.PrivateChannels[i], state);

                                        _sessionId = data.SessionId;
                                        _unavailableGuilds = unavailableGuilds;
                                        CurrentUser = currentUser;
                                        State = state;
                                    }
                                    catch (Exception ex)
                                    {
                                        _connection.CriticalError(new Exception("Processing READY failed", ex));
                                        return;
                                    }

                                    if (ApiClient.AuthTokenType == TokenType.User)
                                        await SyncGuildsAsync().ConfigureAwait(false);

                                    _lastGuildAvailableTime = Environment.TickCount;
                                    _guildDownloadTask = WaitForGuildsAsync(_connection.CancelToken, _gatewayLogger);

                                    await _readyEvent.InvokeAsync().ConfigureAwait(false);

                                    var _ = _connection.CompleteAsync();
                                    await _gatewayLogger.InfoAsync("Ready").ConfigureAwait(false);
                                }
                                break;
                            case "RESUMED":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (RESUMED)").ConfigureAwait(false);

                                    var _ = _connection.CompleteAsync();

                                    //Notify the client that these guilds are available again
                                    foreach (var guild in State.Guilds)
                                    {
                                        if (guild._available)
                                            await _guildAvailableEvent.InvokeAsync(guild).ConfigureAwait(false);
                                    }

                                    await _gatewayLogger.InfoAsync("Resumed previous session").ConfigureAwait(false);
                                }
                                return;

                            //Guilds
                            case "GUILD_CREATE":
                                {
                                    var data = (payload as JToken).ToObject<ExtendedGuild>(_serializer);

                                    if (data.Unavailable == false)
                                    {
                                        type = "GUILD_AVAILABLE";
                                        _lastGuildAvailableTime = Environment.TickCount;
                                        await _gatewayLogger.DebugAsync($"Received Dispatch (GUILD_AVAILABLE)").ConfigureAwait(false);

                                        var guild = State.GetGuild(data.Id);
                                        if (guild != null)
                                        {
                                            guild.Update(State, data);

                                            var unavailableGuilds = _unavailableGuilds;
                                            if (unavailableGuilds != 0)
                                                _unavailableGuilds = unavailableGuilds - 1;
                                            await _guildAvailableEvent.InvokeAsync(guild).ConfigureAwait(false);
                                        }
                                        else
                                        {
                                            await _gatewayLogger.WarningAsync($"GUILD_AVAILABLE referenced an unknown guild.").ConfigureAwait(false);
                                            return;
                                        }
                                    }
                                    else
                                    {
                                        await _gatewayLogger.DebugAsync($"Received Dispatch (GUILD_CREATE)").ConfigureAwait(false);

                                        var guild = AddGuild(data, State);
                                        if (guild != null)
                                        {
                                            if (ApiClient.AuthTokenType == TokenType.User)
                                                await SyncGuildsAsync().ConfigureAwait(false);
                                            await _joinedGuildEvent.InvokeAsync(guild).ConfigureAwait(false);
                                        }
                                        else
                                        {
                                            await _gatewayLogger.WarningAsync($"GUILD_CREATE referenced an unknown guild.").ConfigureAwait(false);
                                            return;
                                        }
                                    }
                                }
                                break;
                            case "GUILD_UPDATE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (GUILD_UPDATE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<API.Guild>(_serializer);
                                    var guild = State.GetGuild(data.Id);
                                    if (guild != null)
                                    {
                                        var before = guild.Clone();
                                        guild.Update(State, data);
                                        await _guildUpdatedEvent.InvokeAsync(before, guild).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("GUILD_UPDATE referenced an unknown guild.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;
                            case "GUILD_EMOJIS_UPDATE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (GUILD_EMOJIS_UPDATE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<API.Gateway.GuildEmojiUpdateEvent>(_serializer);
                                    var guild = State.GetGuild(data.GuildId);
                                    if (guild != null)
                                    {
                                        var before = guild.Clone();
                                        guild.Update(State, data);
                                        await _guildUpdatedEvent.InvokeAsync(before, guild).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("GUILD_EMOJIS_UPDATE referenced an unknown guild.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                return;
                            case "GUILD_SYNC":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (GUILD_SYNC)").ConfigureAwait(false);
                                    var data = (payload as JToken).ToObject<GuildSyncEvent>(_serializer);
                                    var guild = State.GetGuild(data.Id);
                                    if (guild != null)
                                    {
                                        var before = guild.Clone();
                                        guild.Update(State, data);
                                        //This is treated as an extension of GUILD_AVAILABLE
                                        _unavailableGuilds--;
                                        _lastGuildAvailableTime = Environment.TickCount;
                                        await _guildAvailableEvent.InvokeAsync(guild).ConfigureAwait(false);
                                        await _guildUpdatedEvent.InvokeAsync(before, guild).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("GUILD_SYNC referenced an unknown guild.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                return;
                            case "GUILD_DELETE":
                                {
                                    var data = (payload as JToken).ToObject<ExtendedGuild>(_serializer);
                                    if (data.Unavailable == true)
                                    {
                                        type = "GUILD_UNAVAILABLE";
                                        await _gatewayLogger.DebugAsync($"Received Dispatch (GUILD_UNAVAILABLE)").ConfigureAwait(false);

                                        var guild = State.GetGuild(data.Id);
                                        if (guild != null)
                                        {
                                            await _guildUnavailableEvent.InvokeAsync(guild).ConfigureAwait(false);
                                            _unavailableGuilds++;
                                        }
                                        else
                                        {
                                            await _gatewayLogger.WarningAsync($"GUILD_UNAVAILABLE referenced an unknown guild.").ConfigureAwait(false);
                                            return;
                                        }
                                    }
                                    else
                                    {
                                        await _gatewayLogger.DebugAsync($"Received Dispatch (GUILD_DELETE)").ConfigureAwait(false);

                                        _downloadUsersFor.TryRemove(data.Id);
                                        var guild = RemoveGuild(data.Id);
                                        if (guild != null)
                                        {
                                            await _guildUnavailableEvent.InvokeAsync(guild).ConfigureAwait(false);
                                            await _leftGuildEvent.InvokeAsync(guild).ConfigureAwait(false);
                                        }
                                        else
                                        {
                                            await _gatewayLogger.WarningAsync($"GUILD_DELETE referenced an unknown guild.").ConfigureAwait(false);
                                            return;
                                        }
                                    }
                                }
                                break;

                            //Channels
                            case "CHANNEL_CREATE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (CHANNEL_CREATE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<API.Channel>(_serializer);
                                    SocketChannel channel = null;
                                    if (data.GuildId.IsSpecified)
                                    {
                                        var guild = State.GetGuild(data.GuildId.Value);
                                        if (guild != null)
                                        {
                                            channel = guild.AddChannel(State, data);

                                            if (!guild.IsSynced)
                                            {
                                                await _gatewayLogger.DebugAsync("Ignored CHANNEL_CREATE, guild is not synced yet.").ConfigureAwait(false);
                                                return;
                                            }
                                        }
                                        else
                                        {
                                            await _gatewayLogger.WarningAsync("CHANNEL_CREATE referenced an unknown guild.").ConfigureAwait(false);
                                            return;
                                        }
                                    }
                                    else
                                        channel = AddPrivateChannel(data, State) as SocketChannel;

                                    if (channel != null)
                                        await _channelCreatedEvent.InvokeAsync(channel).ConfigureAwait(false);
                                }
                                break;
                            case "CHANNEL_UPDATE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (CHANNEL_UPDATE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<API.Channel>(_serializer);
                                    var channel = State.GetChannel(data.Id);
                                    if (channel != null)
                                    {
                                        var before = channel.Clone();
                                        channel.Update(State, data);

                                        if (!((channel as SocketGuildChannel)?.Guild.IsSynced ?? true))
                                        {
                                            await _gatewayLogger.DebugAsync("Ignored CHANNEL_UPDATE, guild is not synced yet.").ConfigureAwait(false);
                                            return;
                                        }

                                        await _channelUpdatedEvent.InvokeAsync(before, channel).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("CHANNEL_UPDATE referenced an unknown channel.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;
                            case "CHANNEL_DELETE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (CHANNEL_DELETE)").ConfigureAwait(false);

                                    SocketChannel channel = null;
                                    var data = (payload as JToken).ToObject<API.Channel>(_serializer);
                                    if (data.GuildId.IsSpecified)
                                    {
                                        var guild = State.GetGuild(data.GuildId.Value);
                                        if (guild != null)
                                        {
                                            channel = guild.RemoveChannel(State, data.Id);

                                            if (!guild.IsSynced)
                                            {
                                                await _gatewayLogger.DebugAsync("Ignored CHANNEL_DELETE, guild is not synced yet.").ConfigureAwait(false);
                                                return;
                                            }
                                        }
                                        else
                                        {
                                            await _gatewayLogger.WarningAsync("CHANNEL_DELETE referenced an unknown guild.").ConfigureAwait(false);
                                            return;
                                        }
                                    }
                                    else
                                        channel = RemovePrivateChannel(data.Id) as SocketChannel;

                                    if (channel != null)
                                        await _channelDestroyedEvent.InvokeAsync(channel).ConfigureAwait(false);
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("CHANNEL_DELETE referenced an unknown channel.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;

                            //Members
                            case "GUILD_MEMBER_ADD":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (GUILD_MEMBER_ADD)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<GuildMemberAddEvent>(_serializer);
                                    var guild = State.GetGuild(data.GuildId);
                                    if (guild != null)
                                    {
                                        var user = guild.AddOrUpdateUser(data);
                                        guild.MemberCount++;

                                        if (!guild.IsSynced)
                                        {
                                            await _gatewayLogger.DebugAsync("Ignored GUILD_MEMBER_ADD, guild is not synced yet.").ConfigureAwait(false);
                                            return;
                                        }

                                        await _userJoinedEvent.InvokeAsync(user).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("GUILD_MEMBER_ADD referenced an unknown guild.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;
                            case "GUILD_MEMBER_UPDATE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (GUILD_MEMBER_UPDATE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<GuildMemberUpdateEvent>(_serializer);
                                    var guild = State.GetGuild(data.GuildId);
                                    if (guild != null)
                                    {
                                        var user = guild.GetUser(data.User.Id);

                                        if (!guild.IsSynced)
                                        {
                                            await _gatewayLogger.DebugAsync("Ignored GUILD_MEMBER_UPDATE, guild is not synced yet.").ConfigureAwait(false);
                                            return;
                                        }

                                        if (user != null)
                                        {
                                            var before = user.Clone();
                                            user.Update(State, data);
                                            await _guildMemberUpdatedEvent.InvokeAsync(before, user).ConfigureAwait(false);
                                        }
                                        else
                                        {
                                            if (!guild.HasAllMembers)
                                            {
                                                await _gatewayLogger.DebugAsync("Ignored GUILD_MEMBER_UPDATE, this user has not been downloaded yet.").ConfigureAwait(false);
                                                return;
                                            }

                                            await _gatewayLogger.WarningAsync("GUILD_MEMBER_UPDATE referenced an unknown user.").ConfigureAwait(false);
                                            return;
                                        }
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("GUILD_MEMBER_UPDATE referenced an unknown guild.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;
                            case "GUILD_MEMBER_REMOVE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (GUILD_MEMBER_REMOVE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<GuildMemberRemoveEvent>(_serializer);
                                    var guild = State.GetGuild(data.GuildId);
                                    if (guild != null)
                                    {
                                        var user = guild.RemoveUser(data.User.Id);
                                        guild.MemberCount--;

                                        if (!guild.IsSynced)
                                        {
                                            await _gatewayLogger.DebugAsync("Ignored GUILD_MEMBER_REMOVE, guild is not synced yet.").ConfigureAwait(false);
                                            return;
                                        }

                                        if (user != null)
                                            await _userLeftEvent.InvokeAsync(user).ConfigureAwait(false);
                                        else
                                        {
                                            if (!guild.HasAllMembers)
                                            {
                                                await _gatewayLogger.DebugAsync("Ignored GUILD_MEMBER_REMOVE, this user has not been downloaded yet.").ConfigureAwait(false);
                                                return;
                                            }

                                            await _gatewayLogger.WarningAsync("GUILD_MEMBER_REMOVE referenced an unknown user.").ConfigureAwait(false);
                                            return;
                                        }
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("GUILD_MEMBER_REMOVE referenced an unknown guild.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;
                            case "GUILD_MEMBERS_CHUNK":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (GUILD_MEMBERS_CHUNK)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<GuildMembersChunkEvent>(_serializer);
                                    var guild = State.GetGuild(data.GuildId);
                                    if (guild != null)
                                    {
                                        foreach (var memberModel in data.Members)
                                            guild.AddOrUpdateUser(memberModel);

                                        if (guild.DownloadedMemberCount >= guild.MemberCount) //Finished downloading for there
                                        {
                                            guild.CompleteDownloadUsers();
                                            await _guildMembersDownloadedEvent.InvokeAsync(guild).ConfigureAwait(false);
                                        }
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("GUILD_MEMBERS_CHUNK referenced an unknown guild.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;
                            case "CHANNEL_RECIPIENT_ADD":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (CHANNEL_RECIPIENT_ADD)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<RecipientEvent>(_serializer);
                                    var channel = State.GetChannel(data.ChannelId) as SocketGroupChannel;
                                    if (channel != null)
                                    {
                                        var user = channel.AddUser(data.User);
                                        await _recipientAddedEvent.InvokeAsync(user).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("CHANNEL_RECIPIENT_ADD referenced an unknown channel.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;
                            case "CHANNEL_RECIPIENT_REMOVE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (CHANNEL_RECIPIENT_REMOVE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<RecipientEvent>(_serializer);
                                    var channel = State.GetChannel(data.ChannelId) as SocketGroupChannel;
                                    if (channel != null)
                                    {
                                        var user = channel.RemoveUser(data.User.Id);
                                        if (user != null)
                                            await _recipientRemovedEvent.InvokeAsync(user).ConfigureAwait(false);
                                        else
                                        {
                                            await _gatewayLogger.WarningAsync("CHANNEL_RECIPIENT_REMOVE referenced an unknown user.").ConfigureAwait(false);
                                            return;
                                        }
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("CHANNEL_RECIPIENT_ADD referenced an unknown channel.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;

                            //Roles
                            case "GUILD_ROLE_CREATE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (GUILD_ROLE_CREATE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<GuildRoleCreateEvent>(_serializer);
                                    var guild = State.GetGuild(data.GuildId);
                                    if (guild != null)
                                    {
                                        var role = guild.AddRole(data.Role);

                                        if (!guild.IsSynced)
                                        {
                                            await _gatewayLogger.DebugAsync("Ignored GUILD_ROLE_CREATE, guild is not synced yet.").ConfigureAwait(false);
                                            return;
                                        }
                                        await _roleCreatedEvent.InvokeAsync(role).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("GUILD_ROLE_CREATE referenced an unknown guild.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;
                            case "GUILD_ROLE_UPDATE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (GUILD_ROLE_UPDATE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<GuildRoleUpdateEvent>(_serializer);
                                    var guild = State.GetGuild(data.GuildId);
                                    if (guild != null)
                                    {
                                        var role = guild.GetRole(data.Role.Id);
                                        if (role != null)
                                        {
                                            var before = role.Clone();
                                            role.Update(State, data.Role);

                                            if (!guild.IsSynced)
                                            {
                                                await _gatewayLogger.DebugAsync("Ignored GUILD_ROLE_UPDATE, guild is not synced yet.").ConfigureAwait(false);
                                                return;
                                            }

                                            await _roleUpdatedEvent.InvokeAsync(before, role).ConfigureAwait(false);
                                        }
                                        else
                                        {
                                            await _gatewayLogger.WarningAsync("GUILD_ROLE_UPDATE referenced an unknown role.").ConfigureAwait(false);
                                            return;
                                        }
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("GUILD_ROLE_UPDATE referenced an unknown guild.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;
                            case "GUILD_ROLE_DELETE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (GUILD_ROLE_DELETE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<GuildRoleDeleteEvent>(_serializer);
                                    var guild = State.GetGuild(data.GuildId);
                                    if (guild != null)
                                    {
                                        var role = guild.RemoveRole(data.RoleId);
                                        if (role != null)
                                        {
                                            if (!guild.IsSynced)
                                            {
                                                await _gatewayLogger.DebugAsync("Ignored GUILD_ROLE_DELETE, guild is not synced yet.").ConfigureAwait(false);
                                                return;
                                            }

                                            await _roleDeletedEvent.InvokeAsync(role).ConfigureAwait(false);
                                        }
                                        else
                                        {
                                            await _gatewayLogger.WarningAsync("GUILD_ROLE_DELETE referenced an unknown role.").ConfigureAwait(false);
                                            return;
                                        }
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("GUILD_ROLE_DELETE referenced an unknown guild.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;

                            //Bans
                            case "GUILD_BAN_ADD":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (GUILD_BAN_ADD)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<GuildBanEvent>(_serializer);
                                    var guild = State.GetGuild(data.GuildId);
                                    if (guild != null)
                                    {
                                        if (!guild.IsSynced)
                                        {
                                            await _gatewayLogger.DebugAsync("Ignored GUILD_BAN_ADD, guild is not synced yet.").ConfigureAwait(false);
                                            return;
                                        }
                                        
                                        await _userBannedEvent.InvokeAsync(SocketSimpleUser.Create(this, State, data.User), guild).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("GUILD_BAN_ADD referenced an unknown guild.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;
                            case "GUILD_BAN_REMOVE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (GUILD_BAN_REMOVE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<GuildBanEvent>(_serializer);
                                    var guild = State.GetGuild(data.GuildId);
                                    if (guild != null)
                                    {
                                        if (!guild.IsSynced)
                                        {
                                            await _gatewayLogger.DebugAsync("Ignored GUILD_BAN_REMOVE, guild is not synced yet.").ConfigureAwait(false);
                                            return;
                                        }

                                        SocketUser user = State.GetUser(data.User.Id);
                                        if (user == null)
                                            user = SocketSimpleUser.Create(this, State, data.User);
                                        await _userUnbannedEvent.InvokeAsync(user, guild).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("GUILD_BAN_REMOVE referenced an unknown guild.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;

                            //Messages
                            case "MESSAGE_CREATE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (MESSAGE_CREATE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<API.Message>(_serializer);
                                    var channel = State.GetChannel(data.ChannelId) as ISocketMessageChannel;
                                    if (channel != null)
                                    {
                                        var guild = (channel as SocketGuildChannel)?.Guild;
                                        if (guild != null && !guild.IsSynced)
                                        { 
                                            await _gatewayLogger.DebugAsync("Ignored MESSAGE_CREATE, guild is not synced yet.").ConfigureAwait(false);
                                            return;
                                        }

                                        var author = (guild != null ? guild.GetUser(data.Author.Value.Id) : (channel as SocketChannel).GetUser(data.Author.Value.Id)) ??
                                            SocketSimpleUser.Create(this, State, data.Author.Value);

                                        if (author != null)
                                        {
                                            var msg = SocketMessage.Create(this, State, author, channel, data);
                                            SocketChannelHelper.AddMessage(channel, this, msg);
                                            await _messageReceivedEvent.InvokeAsync(msg).ConfigureAwait(false);
                                        }
                                        else
                                        {
                                            await _gatewayLogger.WarningAsync("MESSAGE_CREATE referenced an unknown user.").ConfigureAwait(false);
                                            return;
                                        }
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("MESSAGE_CREATE referenced an unknown channel.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;
                            case "MESSAGE_UPDATE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (MESSAGE_UPDATE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<API.Message>(_serializer);
                                    var channel = State.GetChannel(data.ChannelId) as ISocketMessageChannel;
                                    if (channel != null)
                                    {
                                        var guild = (channel as SocketGuildChannel)?.Guild;
                                        if (guild != null && !guild.IsSynced)
                                        {
                                            await _gatewayLogger.DebugAsync("Ignored MESSAGE_UPDATE, guild is not synced yet.").ConfigureAwait(false);
                                            return;
                                        }

                                        SocketMessage before = null, after = null;
                                        SocketMessage cachedMsg = channel.GetCachedMessage(data.Id);
                                        bool isCached = cachedMsg != null;
                                        if (isCached)
                                        {
                                            before = cachedMsg.Clone();
                                            cachedMsg.Update(State, data);
                                            after = cachedMsg;
                                        }
                                        else if (data.Author.IsSpecified)
                                        {
                                            //Edited message isnt in cache, create a detached one
                                            SocketUser author;
                                            if (guild != null)
                                                author = guild.GetUser(data.Author.Value.Id);
                                            else
                                                author = (channel as SocketChannel).GetUser(data.Author.Value.Id);
                                            if (author == null)
                                                author = SocketSimpleUser.Create(this, State, data.Author.Value);

                                            after = SocketMessage.Create(this, State, author, channel, data);
                                        }
                                        var cacheableBefore = new Cacheable<IMessage, ulong>(before, data.Id, isCached , async () => await channel.GetMessageAsync(data.Id));

                                        await _messageUpdatedEvent.InvokeAsync(cacheableBefore, after, channel).ConfigureAwait(false);                                        
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("MESSAGE_UPDATE referenced an unknown channel.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;
                            case "MESSAGE_DELETE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (MESSAGE_DELETE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<API.Message>(_serializer);
                                    var channel = State.GetChannel(data.ChannelId) as ISocketMessageChannel;
                                    if (channel != null)
                                    {
                                        if (!((channel as SocketGuildChannel)?.Guild.IsSynced ?? true))
                                        {
                                            await _gatewayLogger.DebugAsync("Ignored MESSAGE_DELETE, guild is not synced yet.").ConfigureAwait(false);
                                            return;
                                        }

                                        var msg = SocketChannelHelper.RemoveMessage(channel, this, data.Id);
                                        bool isCached = msg != null;
                                        var cacheable = new Cacheable<IMessage, ulong>(msg, data.Id, isCached, async () => await channel.GetMessageAsync(data.Id));

                                        await _messageDeletedEvent.InvokeAsync(cacheable, channel).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("MESSAGE_DELETE referenced an unknown channel.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;
                            case "MESSAGE_REACTION_ADD":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (MESSAGE_REACTION_ADD)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<API.Gateway.Reaction>(_serializer);
                                    var channel = State.GetChannel(data.ChannelId) as ISocketMessageChannel;
                                    if (channel != null)
                                    {
                                        SocketUserMessage cachedMsg = channel.GetCachedMessage(data.MessageId) as SocketUserMessage;
                                        bool isCached = cachedMsg != null;
                                        var user = await channel.GetUserAsync(data.UserId, CacheMode.CacheOnly);
                                        SocketReaction reaction = SocketReaction.Create(data, channel, cachedMsg, Optional.Create(user));
                                        var cacheable = new Cacheable<IUserMessage, ulong>(cachedMsg, data.MessageId, isCached, async () => await channel.GetMessageAsync(data.MessageId) as IUserMessage);

                                        cachedMsg?.AddReaction(reaction);

                                        await _reactionAddedEvent.InvokeAsync(cacheable, channel, reaction).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("MESSAGE_REACTION_ADD referenced an unknown channel.").ConfigureAwait(false);
                                        return;
                                    }
                                    break;
                                }
                            case "MESSAGE_REACTION_REMOVE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (MESSAGE_REACTION_REMOVE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<API.Gateway.Reaction>(_serializer);
                                    var channel = State.GetChannel(data.ChannelId) as ISocketMessageChannel;
                                    if (channel != null)
                                    {
                                        SocketUserMessage cachedMsg = channel.GetCachedMessage(data.MessageId) as SocketUserMessage;
                                        bool isCached = cachedMsg != null;
                                        var user = await channel.GetUserAsync(data.UserId, CacheMode.CacheOnly);
                                        SocketReaction reaction = SocketReaction.Create(data, channel, cachedMsg, Optional.Create(user));
                                        var cacheable = new Cacheable<IUserMessage, ulong>(cachedMsg, data.MessageId, isCached, async () => await channel.GetMessageAsync(data.MessageId) as IUserMessage);

                                        cachedMsg?.RemoveReaction(reaction);

                                        await _reactionRemovedEvent.InvokeAsync(cacheable, channel, reaction).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("MESSAGE_REACTION_REMOVE referenced an unknown channel.").ConfigureAwait(false);
                                        return;
                                    }
                                    break;
                                }
                            case "MESSAGE_REACTION_REMOVE_ALL":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (MESSAGE_REACTION_REMOVE_ALL)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<RemoveAllReactionsEvent>(_serializer);
                                    var channel = State.GetChannel(data.ChannelId) as ISocketMessageChannel;
                                    if (channel != null)
                                    {
                                        SocketUserMessage cachedMsg = channel.GetCachedMessage(data.MessageId) as SocketUserMessage;
                                        bool isCached = cachedMsg != null;
                                        var cacheable = new Cacheable<IUserMessage, ulong>(cachedMsg, data.MessageId, isCached, async () => await channel.GetMessageAsync(data.MessageId) as IUserMessage);

                                        cachedMsg?.ClearReactions();

                                        await _reactionsClearedEvent.InvokeAsync(cacheable, channel).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("MESSAGE_REACTION_REMOVE_ALL referenced an unknown channel.").ConfigureAwait(false);
                                        return;
                                    }
                                    break;
                                }
                            case "MESSAGE_DELETE_BULK":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (MESSAGE_DELETE_BULK)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<MessageDeleteBulkEvent>(_serializer);
                                    var channel = State.GetChannel(data.ChannelId) as ISocketMessageChannel;
                                    if (channel != null)
                                    {
                                        if (!((channel as SocketGuildChannel)?.Guild.IsSynced ?? true))
                                        {
                                            await _gatewayLogger.DebugAsync("Ignored MESSAGE_DELETE_BULK, guild is not synced yet.").ConfigureAwait(false);
                                            return;
                                        }

                                        foreach (var id in data.Ids)
                                        {
                                            var msg = SocketChannelHelper.RemoveMessage(channel, this, id);
                                            bool isCached = msg != null;
                                            var cacheable = new Cacheable<IMessage, ulong>(msg, id, isCached, async () => await channel.GetMessageAsync(id));
                                            await _messageDeletedEvent.InvokeAsync(cacheable, channel).ConfigureAwait(false);
                                        }
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("MESSAGE_DELETE_BULK referenced an unknown channel.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;

                            //Statuses
                            case "PRESENCE_UPDATE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (PRESENCE_UPDATE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<API.Presence>(_serializer);

                                    if (data.GuildId.IsSpecified)
                                    {
                                        var guild = State.GetGuild(data.GuildId.Value);
                                        if (guild == null)
                                        {
                                            await _gatewayLogger.WarningAsync("PRESENCE_UPDATE referenced an unknown guild.").ConfigureAwait(false);
                                            break;
                                        }
                                        if (!guild.IsSynced)
                                        {
                                            await _gatewayLogger.DebugAsync("Ignored PRESENCE_UPDATE, guild is not synced yet.").ConfigureAwait(false);
                                            return;
                                        }

                                        SocketPresence beforePresence;
                                        SocketGlobalUser beforeGlobal;
                                        var user = guild.GetUser(data.User.Id);
                                        if (user != null)
                                        {
                                            beforePresence = user.Presence.Clone();
                                            beforeGlobal = user.GlobalUser.Clone();
                                            user.Update(State, data);
                                        }
                                        else
                                        {
                                            beforePresence = new SocketPresence(UserStatus.Offline, null);
                                            user = guild.AddOrUpdateUser(data);
                                            beforeGlobal = user.GlobalUser.Clone();
                                        }

                                        if (data.User.Username.IsSpecified || data.User.Avatar.IsSpecified)
                                        {
                                            await _userUpdatedEvent.InvokeAsync(beforeGlobal, user).ConfigureAwait(false);
                                            return;
                                        }
                                        await _userPresenceUpdatedEvent.InvokeAsync(guild, user, beforePresence, user.Presence).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        var channel = State.GetChannel(data.User.Id);
                                        if (channel != null)
                                        {
                                            var user = channel.GetUser(data.User.Id);
                                            var beforePresence = user.Presence.Clone();
                                            var before = user.GlobalUser.Clone();
                                            user.Update(State, data);

                                            await _userPresenceUpdatedEvent.InvokeAsync(Optional.Create<SocketGuild>(), user, beforePresence, user.Presence).ConfigureAwait(false);
                                            if (data.User.Username.IsSpecified || data.User.Avatar.IsSpecified)
                                            {
                                                await _userUpdatedEvent.InvokeAsync(before, user).ConfigureAwait(false);
                                            }                                            
                                        }
                                    }
                                }
                                break;
                            case "TYPING_START":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (TYPING_START)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<TypingStartEvent>(_serializer);
                                    var channel = State.GetChannel(data.ChannelId) as ISocketMessageChannel;
                                    if (channel != null)
                                    {
                                        if (!((channel as SocketGuildChannel)?.Guild.IsSynced ?? true))
                                        {
                                            await _gatewayLogger.DebugAsync("Ignored TYPING_START, guild is not synced yet.").ConfigureAwait(false);
                                            return;
                                        }

                                        var user = (channel as SocketChannel).GetUser(data.UserId);
                                        if (user != null)
                                            await _userIsTypingEvent.InvokeAsync(user, channel).ConfigureAwait(false);
                                    }
                                }
                                break;

                            //Users
                            case "USER_UPDATE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (USER_UPDATE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<API.User>(_serializer);
                                    if (data.Id == CurrentUser.Id)
                                    {
                                        var before = CurrentUser.Clone();
                                        CurrentUser.Update(State, data);
                                        await _selfUpdatedEvent.InvokeAsync(before, CurrentUser).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("Received USER_UPDATE for wrong user.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                break;

                            //Voice
                            case "VOICE_STATE_UPDATE":
                                {
                                    await _gatewayLogger.DebugAsync("Received Dispatch (VOICE_STATE_UPDATE)").ConfigureAwait(false);

                                    var data = (payload as JToken).ToObject<API.VoiceState>(_serializer);
                                    if (data.GuildId.HasValue)
                                    {
                                        SocketUser user;
                                        SocketVoiceState before, after;
                                        if (data.GuildId != null)
                                        {
                                            var guild = State.GetGuild(data.GuildId.Value);
                                            if (guild == null)
                                            {
                                                await _gatewayLogger.WarningAsync("VOICE_STATE_UPDATE referenced an unknown guild.").ConfigureAwait(false);
                                                return;
                                            }
                                            else if (!guild.IsSynced)
                                            {
                                                await _gatewayLogger.DebugAsync("Ignored VOICE_STATE_UPDATE, guild is not synced yet.").ConfigureAwait(false);
                                                return;
                                            }

                                            if (data.ChannelId != null)
                                            {
                                                before = guild.GetVoiceState(data.UserId)?.Clone() ?? SocketVoiceState.Default;
                                                after = guild.AddOrUpdateVoiceState(State, data);
                                                /*if (data.UserId == CurrentUser.Id)
                                                {
                                                    var _ = guild.FinishJoinAudioChannel().ConfigureAwait(false);
                                                }*/
                                            }
                                            else
                                            {
                                                before = guild.RemoveVoiceState(data.UserId) ?? SocketVoiceState.Default;
                                                after = SocketVoiceState.Create(null, data);
                                            }

                                            user = guild.GetUser(data.UserId);
                                        }
                                        else
                                        {
                                            var groupChannel = State.GetChannel(data.ChannelId.Value) as SocketGroupChannel;
                                            if (groupChannel != null)
                                            {
                                                if (data.ChannelId != null)
                                                {
                                                    before = groupChannel.GetVoiceState(data.UserId)?.Clone() ?? SocketVoiceState.Default;
                                                    after = groupChannel.AddOrUpdateVoiceState(State, data);
                                                }
                                                else
                                                {
                                                    before = groupChannel.RemoveVoiceState(data.UserId) ?? SocketVoiceState.Default;
                                                    after = SocketVoiceState.Create(null, data);
                                                }
                                                user = groupChannel.GetUser(data.UserId);
                                            }
                                            else
                                            {
                                                await _gatewayLogger.WarningAsync("VOICE_STATE_UPDATE referenced an unknown channel.").ConfigureAwait(false);
                                                return;
                                            }
                                        }

                                        if (user != null)
                                            await _userVoiceStateUpdatedEvent.InvokeAsync(user, before, after).ConfigureAwait(false);
                                        else
                                        {
                                            await _gatewayLogger.WarningAsync("VOICE_STATE_UPDATE referenced an unknown user.").ConfigureAwait(false);
                                            return;
                                        }
                                    }
                                }
                                break;
                            case "VOICE_SERVER_UPDATE":
                                await _gatewayLogger.DebugAsync("Received Dispatch (VOICE_SERVER_UPDATE)").ConfigureAwait(false);

                                if (AudioMode != AudioMode.Disabled)
                                {
                                    var data = (payload as JToken).ToObject<VoiceServerUpdateEvent>(_serializer);
                                    var guild = State.GetGuild(data.GuildId);
                                    if (guild != null)
                                    {
                                        string endpoint = data.Endpoint.Substring(0, data.Endpoint.LastIndexOf(':'));
                                        var _ = guild.FinishConnectAudio(_nextAudioId++, endpoint, data.Token).ConfigureAwait(false);
                                    }
                                    else
                                    {
                                        await _gatewayLogger.WarningAsync("VOICE_SERVER_UPDATE referenced an unknown guild.").ConfigureAwait(false);
                                        return;
                                    }
                                }
                                return;

                            //Ignored (User only)
                            case "CHANNEL_PINS_ACK":
                                await _gatewayLogger.DebugAsync("Ignored Dispatch (CHANNEL_PINS_ACK)").ConfigureAwait(false);
                                break;
                            case "CHANNEL_PINS_UPDATE":
                                await _gatewayLogger.DebugAsync("Ignored Dispatch (CHANNEL_PINS_UPDATE)").ConfigureAwait(false);
                                break;
                            case "GUILD_INTEGRATIONS_UPDATE":
                                await _gatewayLogger.DebugAsync("Ignored Dispatch (GUILD_INTEGRATIONS_UPDATE)").ConfigureAwait(false);
                                return;
                            case "MESSAGE_ACK":
                                await _gatewayLogger.DebugAsync("Ignored Dispatch (MESSAGE_ACK)").ConfigureAwait(false);
                                return;
                            case "USER_SETTINGS_UPDATE":
                                await _gatewayLogger.DebugAsync("Ignored Dispatch (USER_SETTINGS_UPDATE)").ConfigureAwait(false);
                                return;
                            case "WEBHOOKS_UPDATE":
                                await _gatewayLogger.DebugAsync("Ignored Dispatch (WEBHOOKS_UPDATE)").ConfigureAwait(false);
                                return;

                            //Others
                            default:
                                await _gatewayLogger.WarningAsync($"Unknown Dispatch ({type})").ConfigureAwait(false);
                                return;
                        }
                        break;
                    default:
                        await _gatewayLogger.WarningAsync($"Unknown OpCode ({opCode})").ConfigureAwait(false);
                        return;
                }
            }
            catch (Exception ex)
            {
                await _gatewayLogger.ErrorAsync($"Error handling {opCode}{(type != null ? $" ({type})" : "")}", ex).ConfigureAwait(false);
                return;
            }
        }

        private async Task RunHeartbeatAsync(int intervalMillis, CancellationToken cancelToken)
        {
            try
            {
                await _gatewayLogger.DebugAsync("Heartbeat Started").ConfigureAwait(false);
                while (!cancelToken.IsCancellationRequested)
                {
                    var now = Environment.TickCount;

                    //Did server respond to our last heartbeat, or are we still receiving messages (long load?)
                    if (_heartbeatTimes.Count != 0 && (now - _lastMessageTime) > intervalMillis)
                    {
                        if (ConnectionState == ConnectionState.Connected && (_guildDownloadTask?.IsCompleted ?? true))
                        {
                            _connection.Error(new Exception("Server missed last heartbeat"));
                            return;
                        }
                    }
                    _heartbeatTimes.Enqueue(now);

                    try
                    {
                        await ApiClient.SendHeartbeatAsync(_lastSeq).ConfigureAwait(false);
                    }
                    catch (Exception ex)
                    {
                        await _gatewayLogger.WarningAsync("Heartbeat Errored", ex).ConfigureAwait(false);
                    }

                    await Task.Delay(intervalMillis, cancelToken).ConfigureAwait(false);
                }
                await _gatewayLogger.DebugAsync("Heartbeat Stopped").ConfigureAwait(false);
            }
            catch (OperationCanceledException)
            {
                await _gatewayLogger.DebugAsync("Heartbeat Stopped").ConfigureAwait(false);
            }
            catch (Exception ex)
            {
                await _gatewayLogger.ErrorAsync("Heartbeat Errored", ex).ConfigureAwait(false);
            }
        }
        public async Task WaitForGuildsAsync()
        {
            var downloadTask = _guildDownloadTask;
            if (downloadTask != null)
                await _guildDownloadTask.ConfigureAwait(false);
        }
        private async Task WaitForGuildsAsync(CancellationToken cancelToken, Logger logger)
        {
            //Wait for GUILD_AVAILABLEs
            try
            {
                await logger.DebugAsync("GuildDownloader Started").ConfigureAwait(false);
                while ((_unavailableGuilds != 0) && (Environment.TickCount - _lastGuildAvailableTime < 2000))
                    await Task.Delay(500, cancelToken).ConfigureAwait(false);
                await logger.DebugAsync("GuildDownloader Stopped").ConfigureAwait(false);
            }
            catch (OperationCanceledException)
            {
                await logger.DebugAsync("GuildDownloader Stopped").ConfigureAwait(false);
            }
            catch (Exception ex)
            {
                await logger.ErrorAsync("GuildDownloader Errored", ex).ConfigureAwait(false);
            }
        }
        private async Task SyncGuildsAsync()
        {
            var guildIds = Guilds.Where(x => !x.IsSynced).Select(x => x.Id).ToImmutableArray();
            if (guildIds.Length > 0)
                await ApiClient.SendGuildSyncAsync(guildIds).ConfigureAwait(false);
        }

        internal SocketGuild AddGuild(ExtendedGuild model, ClientState state)
        {
            var guild = SocketGuild.Create(this, state, model);
            state.AddGuild(guild);
            if (model.Large)
                _largeGuilds.Enqueue(model.Id);
            return guild;
        }
        internal SocketGuild RemoveGuild(ulong id)
        {
            var guild = State.RemoveGuild(id);
            if (guild != null)
            {
                foreach (var channel in guild.Channels)
                    State.RemoveChannel(id);
                foreach (var user in guild.Users)
                    user.GlobalUser.RemoveRef(this);
            }
            return guild;
        }

        internal ISocketPrivateChannel AddPrivateChannel(API.Channel model, ClientState state)
        {
            var channel = SocketChannel.CreatePrivate(this, state, model);
            state.AddChannel(channel as SocketChannel);
            return channel;
        }
        internal ISocketPrivateChannel RemovePrivateChannel(ulong id)
        {
            var channel = State.RemoveChannel(id) as ISocketPrivateChannel;
            if (channel != null)
            {
                foreach (var recipient in channel.Recipients)
                    recipient.GlobalUser.RemoveRef(this);
            }
            return channel;
        }

        //IDiscordClient
        ConnectionState IDiscordClient.ConnectionState => _connection.State;

        async Task<IApplication> IDiscordClient.GetApplicationInfoAsync()
            => await GetApplicationInfoAsync().ConfigureAwait(false);

        Task<IChannel> IDiscordClient.GetChannelAsync(ulong id, CacheMode mode)
            => Task.FromResult<IChannel>(GetChannel(id));
        Task<IReadOnlyCollection<IPrivateChannel>> IDiscordClient.GetPrivateChannelsAsync(CacheMode mode)
            => Task.FromResult<IReadOnlyCollection<IPrivateChannel>>(PrivateChannels);
        Task<IReadOnlyCollection<IDMChannel>> IDiscordClient.GetDMChannelsAsync(CacheMode mode)
            => Task.FromResult<IReadOnlyCollection<IDMChannel>>(DMChannels);
        Task<IReadOnlyCollection<IGroupChannel>> IDiscordClient.GetGroupChannelsAsync(CacheMode mode)
            => Task.FromResult<IReadOnlyCollection<IGroupChannel>>(GroupChannels);

        async Task<IReadOnlyCollection<IConnection>> IDiscordClient.GetConnectionsAsync()
            => await GetConnectionsAsync().ConfigureAwait(false);

        async Task<IInvite> IDiscordClient.GetInviteAsync(string inviteId)
            => await GetInviteAsync(inviteId).ConfigureAwait(false);

        Task<IGuild> IDiscordClient.GetGuildAsync(ulong id, CacheMode mode)
            => Task.FromResult<IGuild>(GetGuild(id));
        Task<IReadOnlyCollection<IGuild>> IDiscordClient.GetGuildsAsync(CacheMode mode)
            => Task.FromResult<IReadOnlyCollection<IGuild>>(Guilds);
        async Task<IGuild> IDiscordClient.CreateGuildAsync(string name, IVoiceRegion region, Stream jpegIcon)
            => await CreateGuildAsync(name, region, jpegIcon).ConfigureAwait(false);

        Task<IUser> IDiscordClient.GetUserAsync(ulong id, CacheMode mode)
            => Task.FromResult<IUser>(GetUser(id));
        Task<IUser> IDiscordClient.GetUserAsync(string username, string discriminator)
            => Task.FromResult<IUser>(GetUser(username, discriminator));

        Task<IReadOnlyCollection<IVoiceRegion>> IDiscordClient.GetVoiceRegionsAsync()
            => Task.FromResult<IReadOnlyCollection<IVoiceRegion>>(VoiceRegions);
        Task<IVoiceRegion> IDiscordClient.GetVoiceRegionAsync(string id)
            => Task.FromResult<IVoiceRegion>(GetVoiceRegion(id));

        async Task IDiscordClient.StartAsync()
            => await StartAsync().ConfigureAwait(false);
        async Task IDiscordClient.StopAsync()
            => await StopAsync().ConfigureAwait(false);
    }
}