Start/Stop speaking events on UDP packets (#3578)

* Start/Stop speaking using incomming UDP packets

* Fix ESLint errors

* Updates for styling consistency

Co-Authored-By: Gryffon Bellish <owenbellish@gmail.com>

* Minor improvements

* Acutally use previousTimeout

* Use BaseClient setTimeout and refresh()

* Update README to match node version for refresh()

* Update comment to match startSpeaking

* Correctly report Priority bit

* Fix ESlint errors

README.md

@@ -38,7 +38,7 @@ discord.js is a powerful [Node.js](https://nodejs.org) module that allows you to
 - 100% coverage of the Discord API
 
 ## Installation
-**Node.js 10.0.0 or newer is required.**  
+**Node.js 10.2.0 or newer is required.**  
 Ignore any warnings about unmet peer dependencies, as they're all optional.
 
 Without voice support: `npm install discordjs/discord.js`  

src/client/voice/VoiceConnection.js

@@ -422,7 +422,7 @@ class VoiceConnection extends EventEmitter {
     udp.on('error', err => this.emit('error', err));
     ws.on('ready', this.onReady.bind(this));
     ws.on('sessionDescription', this.onSessionDescription.bind(this));
-    ws.on('speaking', this.onSpeaking.bind(this));
+    ws.on('startSpeaking', this.onStartSpeaking.bind(this));
 
     this.sockets.ws.connect();
   }
@@ -465,16 +465,19 @@ class VoiceConnection extends EventEmitter {
     });
   }
 
+  onStartSpeaking({ user_id, ssrc, speaking }) {
+    this.ssrcMap.set(+ssrc, { userID: user_id, speaking: speaking });
+  }
+
   /**
    * Invoked when a speaking event is received.
    * @param {Object} data The received data
    * @private
    */
-  onSpeaking({ user_id, ssrc, speaking }) {
+  onSpeaking({ user_id, speaking }) {
     speaking = new Speaking(speaking).freeze();
     const guild = this.channel.guild;
     const user = this.client.users.get(user_id);
-    this.ssrcMap.set(+ssrc, user_id);
     const old = this._speaking.get(user_id);
     this._speaking.set(user_id, speaking);
     /**
@@ -504,7 +507,7 @@ class VoiceConnection extends EventEmitter {
     }
   }
 
-  play() {} // eslint-disable-line no-empty-function
+  play() { } // eslint-disable-line no-empty-function
 }
 
 PlayInterface.applyToClass(VoiceConnection);

src/client/voice/networking/VoiceWebSocket.js

@@ -201,9 +201,9 @@ class VoiceWebSocket extends EventEmitter {
         /**
          * Emitted whenever a speaking packet is received.
          * @param {Object} data
-         * @event VoiceWebSocket#speaking
+         * @event VoiceWebSocket#startSpeaking
          */
-        this.emit('speaking', packet.d);
+        this.emit('startSpeaking', packet.d);
         break;
       default:
         /**

src/client/voice/receiver/PacketHandler.js

@@ -3,6 +3,10 @@
 const secretbox = require('../util/Secretbox');
 const EventEmitter = require('events');
 
+// The delay between packets when a user is considered to have stopped speaking
+// https://github.com/discordjs/discord.js/issues/3524#issuecomment-540373200
+const DISCORD_SPEAKING_DELAY = 250;
+
 class Readable extends require('stream').Readable { _read() {} } // eslint-disable-line no-empty-function
 
 class PacketHandler extends EventEmitter {
@@ -11,6 +15,7 @@ class PacketHandler extends EventEmitter {
     this.nonce = Buffer.alloc(24);
     this.receiver = receiver;
     this.streams = new Map();
+    this.speakingTimeouts = new Map();
   }
 
   get connection() {
@@ -72,13 +77,29 @@ class PacketHandler extends EventEmitter {
     return packet;
   }
 
-  userFromSSRC(ssrc) { return this.connection.client.users.get(this.connection.ssrcMap.get(ssrc)); }
-
   push(buffer) {
     const ssrc = buffer.readUInt32BE(8);
-    const user = this.userFromSSRC(ssrc);
-    if (!user) return;
-    let stream = this.streams.get(user.id);
+    const userStat = this.connection.ssrcMap.get(ssrc);
+    if (!userStat) return;
+
+    let speakingTimeout = this.speakingTimeouts.get(ssrc);
+    if (typeof speakingTimeout === 'undefined') {
+      this.connection.onSpeaking({ user_id: userStat.userID, ssrc: ssrc, speaking: userStat.speaking });
+      speakingTimeout = this.receiver.connection.client.setTimeout(() => {
+        try {
+          this.connection.onSpeaking({ user_id: userStat.userID, ssrc: ssrc, speaking: 0 });
+          this.receiver.connection.client.clearTimeout(speakingTimeout);
+          this.speakingTimeouts.delete(ssrc);
+        } catch (ex) {
+          // Connection already closed, ignore
+        }
+      }, DISCORD_SPEAKING_DELAY);
+      this.speakingTimeouts.set(ssrc, speakingTimeout);
+    } else {
+      speakingTimeout.refresh();
+    }
+
+    let stream = this.streams.get(userStat.userID);
     if (!stream) return;
     stream = stream.stream;
     const opusPacket = this.parseBuffer(buffer);