Did more groundwork for AudioClient, added ILogManager

src/Discord.Net.Audio/AudioAPIClient.cs

@@ -0,0 +1,176 @@
+using Discord.API;
+using Discord.API.Voice;
+using Discord.Net.Converters;
+using Discord.Net.WebSockets;
+using Newtonsoft.Json;
+using System;
+using System.Diagnostics;
+using System.Globalization;
+using System.IO;
+using System.IO.Compression;
+using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Discord.Audio
+{
+    public class AudioAPIClient
+    {
+        public const int MaxBitrate = 128;
+        private const string Mode = "xsalsa20_poly1305";
+
+        public event Func<string, string, double, Task> SentRequest { add { _sentRequestEvent.Add(value); } remove { _sentRequestEvent.Remove(value); } }
+        private readonly AsyncEvent<Func<string, string, double, Task>> _sentRequestEvent = new AsyncEvent<Func<string, string, double, Task>>();
+        public event Func<int, Task> SentGatewayMessage { add { _sentGatewayMessageEvent.Add(value); } remove { _sentGatewayMessageEvent.Remove(value); } }
+        private readonly AsyncEvent<Func<int, Task>> _sentGatewayMessageEvent = new AsyncEvent<Func<int, Task>>();
+
+        public event Func<VoiceOpCode, object, Task> ReceivedEvent { add { _receivedEvent.Add(value); } remove { _receivedEvent.Remove(value); } }
+        private readonly AsyncEvent<Func<VoiceOpCode, object, Task>> _receivedEvent = new AsyncEvent<Func<VoiceOpCode, object, Task>>();
+        public event Func<Exception, Task> Disconnected { add { _disconnectedEvent.Add(value); } remove { _disconnectedEvent.Remove(value); } }
+        private readonly AsyncEvent<Func<Exception, Task>> _disconnectedEvent = new AsyncEvent<Func<Exception, Task>>();
+
+        private readonly ulong _userId;
+        private readonly string _token;
+        private readonly JsonSerializer _serializer;
+        private readonly IWebSocketClient _gatewayClient;
+        private readonly SemaphoreSlim _connectionLock;
+        private CancellationTokenSource _connectCancelToken;
+
+        public ulong GuildId { get; }        
+        public string SessionId { get; }
+        public ConnectionState ConnectionState { get; private set; }
+
+        internal AudioAPIClient(ulong guildId, ulong userId, string sessionId, string token, WebSocketProvider webSocketProvider, JsonSerializer serializer = null)
+        {
+            GuildId = guildId;
+            _userId = userId;
+            SessionId = sessionId;
+            _token = token;
+            _connectionLock = new SemaphoreSlim(1, 1);
+
+            _gatewayClient = webSocketProvider();
+            //_gatewayClient.SetHeader("user-agent", DiscordConfig.UserAgent); (Causes issues in .Net 4.6+)
+            _gatewayClient.BinaryMessage += async (data, index, count) =>
+            {
+                using (var compressed = new MemoryStream(data, index + 2, count - 2))
+                using (var decompressed = new MemoryStream())
+                {
+                    using (var zlib = new DeflateStream(compressed, CompressionMode.Decompress))
+                        zlib.CopyTo(decompressed);
+                    decompressed.Position = 0;
+                    using (var reader = new StreamReader(decompressed))
+                    {
+                        var msg = JsonConvert.DeserializeObject<WebSocketMessage>(reader.ReadToEnd());
+                        await _receivedEvent.InvokeAsync((VoiceOpCode)msg.Operation, msg.Payload).ConfigureAwait(false);
+                    }
+                }
+            };
+            _gatewayClient.TextMessage += async text =>
+            {
+                var msg = JsonConvert.DeserializeObject<WebSocketMessage>(text);
+                await _receivedEvent.InvokeAsync((VoiceOpCode)msg.Operation, msg.Payload).ConfigureAwait(false);
+            };
+            _gatewayClient.Closed += async ex =>
+            {
+                await DisconnectAsync().ConfigureAwait(false);
+                await _disconnectedEvent.InvokeAsync(ex).ConfigureAwait(false);
+            };
+
+            _serializer = serializer ?? new JsonSerializer { ContractResolver = new DiscordContractResolver() };
+        }
+
+        public Task SendAsync(VoiceOpCode opCode, object payload, RequestOptions options = null)
+        {
+            byte[] bytes = null;
+            payload = new WebSocketMessage { Operation = (int)opCode, Payload = payload };
+            if (payload != null)
+                bytes = Encoding.UTF8.GetBytes(SerializeJson(payload));
+            //TODO: Send
+            return Task.CompletedTask;
+        }
+
+        //WebSocket
+        public async Task SendHeartbeatAsync(RequestOptions options = null)
+        {
+            await SendAsync(VoiceOpCode.Heartbeat, DateTimeOffset.UtcNow.ToUnixTimeMilliseconds(), options: options).ConfigureAwait(false);
+        }
+        public async Task SendIdentityAsync(ulong guildId, ulong userId, string sessionId, string token)
+        {
+            await SendAsync(VoiceOpCode.Identify, new IdentifyParams
+            {
+                GuildId = guildId,
+                UserId = userId,
+                SessionId = sessionId,
+                Token = token
+            });
+        }
+
+        public async Task ConnectAsync(string url)
+        {
+            await _connectionLock.WaitAsync().ConfigureAwait(false);
+            try
+            {
+                await ConnectInternalAsync(url).ConfigureAwait(false);
+            }
+            finally { _connectionLock.Release(); }
+        }
+        private async Task ConnectInternalAsync(string url)
+        {
+            ConnectionState = ConnectionState.Connecting;
+            try
+            {
+                _connectCancelToken = new CancellationTokenSource();
+                _gatewayClient.SetCancelToken(_connectCancelToken.Token);                
+                await _gatewayClient.ConnectAsync(url).ConfigureAwait(false);
+
+                await SendIdentityAsync(GuildId, _userId, SessionId, _token).ConfigureAwait(false);
+
+                ConnectionState = ConnectionState.Connected;
+            }
+            catch (Exception)
+            {
+                await DisconnectInternalAsync().ConfigureAwait(false);
+                throw;
+            }
+        }
+
+        public async Task DisconnectAsync()
+        {
+            await _connectionLock.WaitAsync().ConfigureAwait(false);
+            try
+            {
+                await DisconnectInternalAsync().ConfigureAwait(false);
+            }
+            finally { _connectionLock.Release(); }
+        }
+        private async Task DisconnectInternalAsync()
+        {
+            if (ConnectionState == ConnectionState.Disconnected) return;
+            ConnectionState = ConnectionState.Disconnecting;
+            
+            try { _connectCancelToken?.Cancel(false); }
+            catch { }
+
+            await _gatewayClient.DisconnectAsync().ConfigureAwait(false);
+
+            ConnectionState = ConnectionState.Disconnected;
+        }
+
+        //Helpers
+        private static double ToMilliseconds(Stopwatch stopwatch) => Math.Round((double)stopwatch.ElapsedTicks / (double)Stopwatch.Frequency * 1000.0, 2);
+        private string SerializeJson(object value)
+        {
+            var sb = new StringBuilder(256);
+            using (TextWriter text = new StringWriter(sb, CultureInfo.InvariantCulture))
+            using (JsonWriter writer = new JsonTextWriter(text))
+                _serializer.Serialize(writer, value);
+            return sb.ToString();
+        }
+        private T DeserializeJson<T>(Stream jsonStream)
+        {
+            using (TextReader text = new StreamReader(jsonStream))
+            using (JsonReader reader = new JsonTextReader(text))
+                return _serializer.Deserialize<T>(reader);
+        }
+    }
+}

src/Discord.Net.Audio/AudioClient.cs

@@ -1,13 +1,9 @@
-using Discord.API;
-using Discord.API.Voice;
+using Discord.API.Voice;
+using Discord.Logging;
 using Discord.Net.Converters;
-using Discord.Net.WebSockets;
 using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
 using System;
-using System.Diagnostics;
-using System.Globalization;
-using System.IO;
-using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 
@@ -15,60 +11,115 @@ namespace Discord.Audio
 {
     public class AudioClient
     {
-        public const int MaxBitrate = 128;
-
-        private const string Mode = "xsalsa20_poly1305";
-
-        private readonly JsonSerializer _serializer;
-        private readonly IWebSocketClient _gatewayClient;
-        private readonly SemaphoreSlim _connectionLock;
-        private CancellationTokenSource _connectCancelToken;
-
-        public ConnectionState ConnectionState { get; private set; }
-
-        internal AudioClient(WebSocketProvider provider, JsonSerializer serializer = null)
+        public event Func<Task> Connected
         {
+            add { _connectedEvent.Add(value); }
+            remove { _connectedEvent.Remove(value); }
+        }
+        private readonly AsyncEvent<Func<Task>> _connectedEvent = new AsyncEvent<Func<Task>>();
+        public event Func<Task> Disconnected
+        {
+            add { _disconnectedEvent.Add(value); }
+            remove { _disconnectedEvent.Remove(value); }
+        }
+        private readonly AsyncEvent<Func<Task>> _disconnectedEvent = new AsyncEvent<Func<Task>>();
+        public event Func<int, int, Task> LatencyUpdated
+        {
+            add { _latencyUpdatedEvent.Add(value); }
+            remove { _latencyUpdatedEvent.Remove(value); }
+        }
+        private readonly AsyncEvent<Func<int, int, Task>> _latencyUpdatedEvent = new AsyncEvent<Func<int, int, Task>>();
+
+        private readonly ILogger _webSocketLogger;
+#if BENCHMARK
+        private readonly ILogger _benchmarkLogger;
+#endif
+        private readonly JsonSerializer _serializer;
+        private readonly int _connectionTimeout, _reconnectDelay, _failedReconnectDelay;
+        internal readonly SemaphoreSlim _connectionLock;
+
+        private TaskCompletionSource<bool> _connectTask;
+        private CancellationTokenSource _cancelToken;
+        private Task _heartbeatTask, _reconnectTask;
+        private long _heartbeatTime;
+        private bool _isReconnecting;
+        private string _url;
+
+        public AudioAPIClient ApiClient { get; private set; }
+        /// <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; }
+
+        /// <summary> Creates a new REST/WebSocket discord client. </summary>
+        internal AudioClient(ulong guildId, ulong userId, string sessionId, string token, AudioConfig config, ILogManager logManager)
+        {
+            _connectionTimeout = config.ConnectionTimeout;
+            _reconnectDelay = config.ReconnectDelay;
+            _failedReconnectDelay = config.FailedReconnectDelay;
+
+            _webSocketLogger = logManager.CreateLogger("AudioWS");
+#if BENCHMARK
+            _benchmarkLogger = logManager.CreateLogger("Benchmark");
+#endif
+
             _connectionLock = new SemaphoreSlim(1, 1);
 
-            _serializer = serializer ?? new JsonSerializer { ContractResolver = new DiscordContractResolver() };
+            _serializer = new JsonSerializer { ContractResolver = new DiscordContractResolver() };
+            _serializer.Error += (s, e) =>
+            {
+                _webSocketLogger.WarningAsync(e.ErrorContext.Error).GetAwaiter().GetResult();
+                e.ErrorContext.Handled = true;
+            };
+            
+            var webSocketProvider = config.WebSocketProvider; //TODO: Clean this check
+            ApiClient = new AudioAPIClient(guildId, userId, sessionId, token, config.WebSocketProvider);
+
+            ApiClient.SentGatewayMessage += async opCode => await _webSocketLogger.DebugAsync($"Sent {(VoiceOpCode)opCode}").ConfigureAwait(false);
+            ApiClient.ReceivedEvent += ProcessMessageAsync;
+            ApiClient.Disconnected += async ex =>
+            {
+                if (ex != null)
+                {
+                    await _webSocketLogger.WarningAsync($"Connection Closed: {ex.Message}").ConfigureAwait(false);
+                    await StartReconnectAsync().ConfigureAwait(false);
+                }
+                else
+                    await _webSocketLogger.WarningAsync($"Connection Closed").ConfigureAwait(false);
+            };
         }
 
-        public Task SendAsync(VoiceOpCode opCode, object payload, RequestOptions options = null)
-        {
-            byte[] bytes = null;
-            payload = new WebSocketMessage { Operation = (int)opCode, Payload = payload };
-            if (payload != null)
-                bytes = Encoding.UTF8.GetBytes(SerializeJson(payload));
-            //TODO: Send
-            return Task.CompletedTask;
-        }
-
-        //Gateway
-        public async Task SendHeartbeatAsync(int lastSeq, RequestOptions options = null)
-        {
-            await SendAsync(VoiceOpCode.Heartbeat, lastSeq, options: options).ConfigureAwait(false);
-        }
-
-
+        /// <inheritdoc />
         public async Task ConnectAsync(string url)
         {
             await _connectionLock.WaitAsync().ConfigureAwait(false);
             try
             {
+                _isReconnecting = false;
                 await ConnectInternalAsync(url).ConfigureAwait(false);
             }
             finally { _connectionLock.Release(); }
         }
         private async Task ConnectInternalAsync(string url)
         {
+            var state = ConnectionState;
+            if (state == ConnectionState.Connecting || state == ConnectionState.Connected)
+                await DisconnectInternalAsync().ConfigureAwait(false);
+
             ConnectionState = ConnectionState.Connecting;
+            await _webSocketLogger.InfoAsync("Connecting").ConfigureAwait(false);
             try
             {
-                _connectCancelToken = new CancellationTokenSource();
-                _gatewayClient.SetCancelToken(_connectCancelToken.Token);                
-                await _gatewayClient.ConnectAsync(url).ConfigureAwait(false);
+                _url = url;
+                _connectTask = new TaskCompletionSource<bool>();
+                _cancelToken = new CancellationTokenSource();
+                await ApiClient.ConnectAsync(url).ConfigureAwait(false);
+                await _connectedEvent.InvokeAsync().ConfigureAwait(false);
+
+                await _connectTask.Task.ConfigureAwait(false);
 
                 ConnectionState = ConnectionState.Connected;
+                await _webSocketLogger.InfoAsync("Connected").ConfigureAwait(false);
             }
             catch (Exception)
             {
@@ -76,12 +127,13 @@ namespace Discord.Audio
                 throw;
             }
         }
-
+        /// <inheritdoc />
         public async Task DisconnectAsync()
         {
             await _connectionLock.WaitAsync().ConfigureAwait(false);
             try
             {
+                _isReconnecting = false;
                 await DisconnectInternalAsync().ConfigureAwait(false);
             }
             finally { _connectionLock.Release(); }
@@ -90,30 +142,163 @@ namespace Discord.Audio
         {
             if (ConnectionState == ConnectionState.Disconnected) return;
             ConnectionState = ConnectionState.Disconnecting;
-            
-            try { _connectCancelToken?.Cancel(false); }
-            catch { }
+            await _webSocketLogger.InfoAsync("Disconnecting").ConfigureAwait(false);
 
-            await _gatewayClient.DisconnectAsync().ConfigureAwait(false);
+            //Signal tasks to complete
+            try { _cancelToken.Cancel(); } catch { }
+
+            //Disconnect from server
+            await ApiClient.DisconnectAsync().ConfigureAwait(false);
+
+            //Wait for tasks to complete
+            var heartbeatTask = _heartbeatTask;
+            if (heartbeatTask != null)
+                await heartbeatTask.ConfigureAwait(false);
+            _heartbeatTask = null;
 
             ConnectionState = ConnectionState.Disconnected;
+            await _webSocketLogger.InfoAsync("Disconnected").ConfigureAwait(false);
+
+            await _disconnectedEvent.InvokeAsync().ConfigureAwait(false);
         }
 
-        //Helpers
-        private static double ToMilliseconds(Stopwatch stopwatch) => Math.Round((double)stopwatch.ElapsedTicks / (double)Stopwatch.Frequency * 1000.0, 2);
-        private string SerializeJson(object value)
+        private async Task StartReconnectAsync()
         {
-            var sb = new StringBuilder(256);
-            using (TextWriter text = new StringWriter(sb, CultureInfo.InvariantCulture))
-            using (JsonWriter writer = new JsonTextWriter(text))
-                _serializer.Serialize(writer, value);
-            return sb.ToString();
+            //TODO: Is this thread-safe?
+            if (_reconnectTask != null) return;
+
+            await _connectionLock.WaitAsync().ConfigureAwait(false);
+            try
+            {
+                if (_reconnectTask != null) return;
+                _isReconnecting = true;
+                _reconnectTask = ReconnectInternalAsync();
+            }
+            finally { _connectionLock.Release(); }
         }
-        private T DeserializeJson<T>(Stream jsonStream)
+        private async Task ReconnectInternalAsync()
         {
-            using (TextReader text = new StreamReader(jsonStream))
-            using (JsonReader reader = new JsonTextReader(text))
-                return _serializer.Deserialize<T>(reader);
+            try
+            {
+                int nextReconnectDelay = 1000;
+                while (_isReconnecting)
+                {
+                    try
+                    {
+                        await Task.Delay(nextReconnectDelay).ConfigureAwait(false);
+                        nextReconnectDelay *= 2;
+                        if (nextReconnectDelay > 30000)
+                            nextReconnectDelay = 30000;
+
+                        await _connectionLock.WaitAsync().ConfigureAwait(false);
+                        try
+                        {
+                            await ConnectInternalAsync(_url).ConfigureAwait(false);
+                        }
+                        finally { _connectionLock.Release(); }
+                        return;
+                    }
+                    catch (Exception ex)
+                    {
+                        await _webSocketLogger.WarningAsync("Reconnect failed", ex).ConfigureAwait(false);
+                    }
+                }
+            }
+            finally
+            {
+                await _connectionLock.WaitAsync().ConfigureAwait(false);
+                try
+                {
+                    _isReconnecting = false;
+                    _reconnectTask = null;
+                }
+                finally { _connectionLock.Release(); }
+            }
+        }
+
+        private async Task ProcessMessageAsync(VoiceOpCode opCode, object payload)
+        {
+#if BENCHMARK
+            Stopwatch stopwatch = Stopwatch.StartNew();
+            try
+            {
+#endif
+            try
+            {
+                switch (opCode)
+                {
+                    /*case VoiceOpCode.Ready:
+                        {
+                            await _webSocketLogger.DebugAsync("Received Ready").ConfigureAwait(false);
+                            var data = (payload as JToken).ToObject<ReadyEvent>(_serializer);
+                            
+                            _heartbeatTime = 0;
+                            _heartbeatTask = RunHeartbeatAsync(data.HeartbeatInterval, _cancelToken.Token);
+                        }
+                        break;*/
+                    case VoiceOpCode.HeartbeatAck:
+                        {
+                            await _webSocketLogger.DebugAsync("Received HeartbeatAck").ConfigureAwait(false);
+
+                            var heartbeatTime = _heartbeatTime;
+                            if (heartbeatTime != 0)
+                            {
+                                int latency = (int)(Environment.TickCount - _heartbeatTime);
+                                _heartbeatTime = 0;
+                                await _webSocketLogger.VerboseAsync($"Latency = {latency} ms").ConfigureAwait(false);
+
+                                int before = Latency;
+                                Latency = latency;
+
+                                await _latencyUpdatedEvent.InvokeAsync(before, latency).ConfigureAwait(false);
+                            }
+                        }
+                        break;
+                    default:
+                        await _webSocketLogger.WarningAsync($"Unknown OpCode ({opCode})").ConfigureAwait(false);
+                        return;
+                }
+            }
+            catch (Exception ex)
+            {
+                await _webSocketLogger.ErrorAsync($"Error handling {opCode}", ex).ConfigureAwait(false);
+                return;
+            }
+#if BENCHMARK
+            }
+            finally
+            {
+                stopwatch.Stop();
+                double millis = Math.Round(stopwatch.ElapsedTicks / (double)Stopwatch.Frequency * 1000.0, 2);
+                await _benchmarkLogger.DebugAsync($"{millis} ms").ConfigureAwait(false);
+            }
+#endif
+        }
+
+        private async Task RunHeartbeatAsync(int intervalMillis, CancellationToken cancelToken)
+        {
+            //Clean this up when Discord's session patch is live
+            try
+            {
+                while (!cancelToken.IsCancellationRequested)
+                {
+                    await Task.Delay(intervalMillis, cancelToken).ConfigureAwait(false);
+
+                    if (_heartbeatTime != 0) //Server never responded to our last heartbeat
+                    {
+                        if (ConnectionState == ConnectionState.Connected)
+                        {
+                            await _webSocketLogger.WarningAsync("Server missed last heartbeat").ConfigureAwait(false);
+                            await StartReconnectAsync().ConfigureAwait(false);
+                            return;
+                        }
+                    }
+                    else
+                        _heartbeatTime = Environment.TickCount;
+                    await ApiClient.SendHeartbeatAsync().ConfigureAwait(false);
+                }
+            }
+            catch (OperationCanceledException) { }
         }
     }
 }

src/Discord.Net.Audio/AudioConfig.cs

@@ -0,0 +1,17 @@
+using Discord.Net.WebSockets;
+
+namespace Discord.Audio
+{
+    public class AudioConfig
+    {
+        /// <summary> Gets or sets the time (in milliseconds) to wait for the websocket to connect and initialize. </summary>
+        public int ConnectionTimeout { get; set; } = 30000;
+        /// <summary> Gets or sets the time (in milliseconds) to wait after an unexpected disconnect before reconnecting. </summary>
+        public int ReconnectDelay { get; set; } = 1000;
+        /// <summary> Gets or sets the time (in milliseconds) to wait after an reconnect fails before retrying. </summary>
+        public int FailedReconnectDelay { get; set; } = 15000;
+
+        /// <summary> Gets or sets the provider used to generate new websocket connections. </summary>
+        public WebSocketProvider WebSocketProvider { get; set; } = () => new DefaultWebSocketClient();
+    }
+}

src/Discord.Net.Audio/Logger.cs

@@ -0,0 +1,6 @@
+namespace Discord.Audio
+{
+    internal class Logger
+    {
+    }
+}

src/Discord.Net.Audio/Opus/OpusEncoder.cs

@@ -36,7 +36,7 @@ namespace Discord.Audio.Opus
         {
             if (channels != 1 && channels != 2)
                 throw new ArgumentOutOfRangeException(nameof(channels));
-            if (bitrate != null && (bitrate < 1 || bitrate > AudioClient.MaxBitrate))
+            if (bitrate != null && (bitrate < 1 || bitrate > AudioAPIClient.MaxBitrate))
                 throw new ArgumentOutOfRangeException(nameof(bitrate));
 
             OpusError error;

src/Discord.Net.Audio/Utilities/AsyncEvent.cs

@@ -0,0 +1,74 @@
+using System;
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.Threading.Tasks;
+
+namespace Discord
+{
+    public class AsyncEvent<T>
+    {
+        private readonly object _subLock = new object();
+        internal ImmutableArray<T> _subscriptions;
+
+        public IReadOnlyList<T> Subscriptions => _subscriptions;
+
+        public AsyncEvent()
+        {
+            _subscriptions = ImmutableArray.Create<T>();
+        }
+
+        public void Add(T subscriber)
+        {
+            lock (_subLock)
+                _subscriptions = _subscriptions.Add(subscriber);
+        }
+        public void Remove(T subscriber)
+        {
+            lock (_subLock)
+                _subscriptions = _subscriptions.Remove(subscriber);
+        }
+    }
+
+    public static class EventExtensions
+    { 
+        public static async Task InvokeAsync(this AsyncEvent<Func<Task>> eventHandler)
+        {
+            var subscribers = eventHandler.Subscriptions;
+            if (subscribers.Count > 0)
+            {
+                for (int i = 0; i < subscribers.Count; i++)
+                    await subscribers[i].Invoke().ConfigureAwait(false);
+            }
+        }
+        public static async Task InvokeAsync<T>(this AsyncEvent<Func<T, Task>> eventHandler, T arg)
+        {
+            var subscribers = eventHandler.Subscriptions;
+            for (int i = 0; i < subscribers.Count; i++)
+                await subscribers[i].Invoke(arg).ConfigureAwait(false);
+        }
+        public static async Task InvokeAsync<T1, T2>(this AsyncEvent<Func<T1, T2, Task>> eventHandler, T1 arg1, T2 arg2)
+        {
+            var subscribers = eventHandler.Subscriptions;
+            for (int i = 0; i < subscribers.Count; i++)
+                await subscribers[i].Invoke(arg1, arg2).ConfigureAwait(false);
+        }
+        public static async Task InvokeAsync<T1, T2, T3>(this AsyncEvent<Func<T1, T2, T3, Task>> eventHandler, T1 arg1, T2 arg2, T3 arg3)
+        {
+            var subscribers = eventHandler.Subscriptions;
+            for (int i = 0; i < subscribers.Count; i++)
+                await subscribers[i].Invoke(arg1, arg2, arg3).ConfigureAwait(false);
+        }
+        public static async Task InvokeAsync<T1, T2, T3, T4>(this AsyncEvent<Func<T1, T2, T3, T4, Task>> eventHandler, T1 arg1, T2 arg2, T3 arg3, T4 arg4)
+        {
+            var subscribers = eventHandler.Subscriptions;
+            for (int i = 0; i < subscribers.Count; i++)
+                await subscribers[i].Invoke(arg1, arg2, arg3, arg4).ConfigureAwait(false);
+        }
+        public static async Task InvokeAsync<T1, T2, T3, T4, T5>(this AsyncEvent<Func<T1, T2, T3, T4, T5, Task>> eventHandler, T1 arg1, T2 arg2, T3 arg3, T4 arg4, T5 arg5)
+        {
+            var subscribers = eventHandler.Subscriptions;
+            for (int i = 0; i < subscribers.Count; i++)
+                await subscribers[i].Invoke(arg1, arg2, arg3, arg4, arg5).ConfigureAwait(false);
+        }
+    }
+}

src/Discord.Net/API/Gateway/GatewayOpCode.cs

@@ -2,7 +2,7 @@
 {
     public enum GatewayOpCode : byte
     {
-        /// <summary> S→C - Used to send most events. </summary>
+        /// <summary> C←S - Used to send most events. </summary>
         Dispatch = 0,
         /// <summary> C↔S - Used to keep the connection alive and measure latency. </summary>
         Heartbeat = 1,
@@ -16,15 +16,15 @@
         VoiceServerPing = 5,
         /// <summary> C→S - Used to resume a connection after a redirect occurs. </summary>
         Resume = 6,
-        /// <summary> S→C - Used to notify a client that they must reconnect to another gateway. </summary>
+        /// <summary> C←S - Used to notify a client that they must reconnect to another gateway. </summary>
         Reconnect = 7,
         /// <summary> C→S - Used to request all members that were withheld by large_threshold </summary>
         RequestGuildMembers = 8,
-        /// <summary> S→C - Used to notify the client that their session has expired and cannot be resumed. </summary>
+        /// <summary> C←S - Used to notify the client that their session has expired and cannot be resumed. </summary>
         InvalidSession = 9,
-        /// <summary> S→C - Used to provide information to the client immediately on connection. </summary>
+        /// <summary> C←S - Used to provide information to the client immediately on connection. </summary>
         Hello = 10,
-        /// <summary> S→C - Used to reply to a client's heartbeat. </summary>
+        /// <summary> C←S - Used to reply to a client's heartbeat. </summary>
         HeartbeatAck = 11
     }
 }

src/Discord.Net/API/Voice/IdentifyParams.cs

@@ -0,0 +1,16 @@
+using Newtonsoft.Json;
+
+namespace Discord.API.Voice
+{
+    public class IdentifyParams
+    {
+        [JsonProperty("server_id")]
+        public ulong GuildId { get; set; }
+        [JsonProperty("user_id")]
+        public ulong UserId { get; set; }
+        [JsonProperty("session_id")]
+        public string SessionId { get; set; }
+        [JsonProperty("token")]
+        public string Token { get; set; }
+    }
+}

src/Discord.Net/API/Voice/VoiceOpCode.cs

@@ -8,8 +8,10 @@
         SelectProtocol = 1,
         /// <summary> C←S - Used to notify that the voice connection was successful and informs the client of available protocols. </summary>
         Ready = 2,
-        /// <summary> C↔S - Used to keep the connection alive and measure latency. </summary>
+        /// <summary> C→S - Used to keep the connection alive and measure latency. </summary>
         Heartbeat = 3,
+        /// <summary> C←S - Used to reply to a client's heartbeat. </summary>
+        HeartbeatAck = 3,
         /// <summary> C←S - Used to provide an encryption key to the client. </summary>
         SessionDescription = 4,
         /// <summary> C↔S - Used to inform that a certain user is speaking. </summary>

src/Discord.Net/DiscordClient.cs

@@ -24,7 +24,7 @@ namespace Discord
         public event Func<Task> LoggedOut { add { _loggedOutEvent.Add(value); } remove { _loggedOutEvent.Remove(value); } }
         private readonly AsyncEvent<Func<Task>> _loggedOutEvent = new AsyncEvent<Func<Task>>();
 
-        internal readonly Logger _discordLogger, _restLogger, _queueLogger;
+        internal readonly ILogger _discordLogger, _restLogger, _queueLogger;
         internal readonly SemaphoreSlim _connectionLock;
         internal readonly LogManager _log;
         internal readonly RequestQueue _requestQueue;

src/Discord.Net/DiscordSocketClient.cs

@@ -2,7 +2,6 @@
 using Discord.Extensions;
 using Discord.Logging;
 using Discord.Net.Converters;
-using Discord.Net.WebSockets;
 using Newtonsoft.Json;
 using Newtonsoft.Json.Linq;
 using System;
@@ -21,9 +20,9 @@ namespace Discord
     public partial class DiscordSocketClient : DiscordClient, IDiscordClient
     {
         private readonly ConcurrentQueue<ulong> _largeGuilds;
-        private readonly Logger _gatewayLogger;
+        private readonly ILogger _gatewayLogger;
 #if BENCHMARK
-        private readonly Logger _benchmarkLogger;
+        private readonly ILogger _benchmarkLogger;
 #endif
         private readonly JsonSerializer _serializer;
         private readonly int _connectionTimeout, _reconnectDelay, _failedReconnectDelay;
@@ -150,6 +149,11 @@ namespace Discord
                 await ApiClient.ConnectAsync().ConfigureAwait(false);
                 await _connectedEvent.InvokeAsync().ConfigureAwait(false);
 
+                if (_sessionId != null)
+                    await ApiClient.SendResumeAsync(_sessionId, _lastSeq).ConfigureAwait(false);
+                else
+                    await ApiClient.SendIdentifyAsync().ConfigureAwait(false);
+
                 await _connectTask.Task.ConfigureAwait(false);
                 
                 ConnectionState = ConnectionState.Connected;
@@ -205,6 +209,7 @@ namespace Discord
 
             await _disconnectedEvent.InvokeAsync().ConfigureAwait(false);
         }
+
         private async Task StartReconnectAsync()
         {
             //TODO: Is this thread-safe?
@@ -416,10 +421,6 @@ namespace Discord
                             await _gatewayLogger.DebugAsync("Received Hello").ConfigureAwait(false);
                             var data = (payload as JToken).ToObject<HelloEvent>(_serializer);
 
-                            if (_sessionId != null)
-                                await ApiClient.SendResumeAsync(_sessionId, _lastSeq).ConfigureAwait(false);
-                            else
-                                await ApiClient.SendIdentifyAsync().ConfigureAwait(false);
                             _heartbeatTime = 0;
                             _heartbeatTask = RunHeartbeatAsync(data.HeartbeatInterval, _cancelToken.Token);
                         }

src/Discord.Net/Logging/ILogManager.cs

@@ -0,0 +1,36 @@
+using System;
+using System.Threading.Tasks;
+
+namespace Discord.Logging
+{
+    public interface ILogManager
+    {
+        LogSeverity Level { get; }
+
+        Task LogAsync(LogSeverity severity, string source, string message, Exception ex = null);
+        Task LogAsync(LogSeverity severity, string source, FormattableString message, Exception ex = null);
+        Task LogAsync(LogSeverity severity, string source, Exception ex);
+
+        Task ErrorAsync(string source, string message, Exception ex = null);
+        Task ErrorAsync(string source, FormattableString message, Exception ex = null);
+        Task ErrorAsync(string source, Exception ex);
+
+        Task WarningAsync(string source, string message, Exception ex = null);
+        Task WarningAsync(string source, FormattableString message, Exception ex = null);
+        Task WarningAsync(string source, Exception ex);
+
+        Task InfoAsync(string source, string message, Exception ex = null);
+        Task InfoAsync(string source, FormattableString message, Exception ex = null);
+        Task InfoAsync(string source, Exception ex);
+
+        Task VerboseAsync(string source, string message, Exception ex = null);
+        Task VerboseAsync(string source, FormattableString message, Exception ex = null);
+        Task VerboseAsync(string source, Exception ex);
+
+        Task DebugAsync(string source, string message, Exception ex = null);
+        Task DebugAsync(string source, FormattableString message, Exception ex = null);
+        Task DebugAsync(string source, Exception ex);
+
+        ILogger CreateLogger(string name);
+    }
+}

src/Discord.Net/Logging/LogManager.cs

@@ -3,7 +3,7 @@ using System.Threading.Tasks;
 
 namespace Discord.Logging
 {
-    internal class LogManager : ILogger
+    internal class LogManager : ILogManager, ILogger
     {
         public LogSeverity Level { get; }
 
@@ -111,6 +111,6 @@ namespace Discord.Logging
         Task ILogger.DebugAsync(Exception ex)
             => LogAsync(LogSeverity.Debug, "Discord", ex);
 
-        public Logger CreateLogger(string name) => new Logger(this, name);
+        public ILogger CreateLogger(string name) => new Logger(this, name);
     }
 }