chore: monorepo setup (#7175)

packages/voice/src/receive/SSRCMap.ts

@@ -0,0 +1,112 @@
+import { TypedEmitter } from 'tiny-typed-emitter';
+import type { Awaited } from '../util/util';
+
+/**
+ * The known data for a user in a Discord voice connection.
+ */
+export interface VoiceUserData {
+	/**
+	 * The SSRC of the user's audio stream.
+	 */
+	audioSSRC: number;
+
+	/**
+	 * The SSRC of the user's video stream (if one exists)
+	 * Cannot be 0. If undefined, the user has no video stream.
+	 */
+	videoSSRC?: number;
+
+	/**
+	 * The Discord user id of the user.
+	 */
+	userId: string;
+}
+
+/**
+ * The events that an SSRCMap may emit.
+ */
+export interface SSRCMapEvents {
+	create: (newData: VoiceUserData) => Awaited<void>;
+	update: (oldData: VoiceUserData | undefined, newData: VoiceUserData) => Awaited<void>;
+	delete: (deletedData: VoiceUserData) => Awaited<void>;
+}
+
+/**
+ * Maps audio SSRCs to data of users in voice connections.
+ */
+export class SSRCMap extends TypedEmitter<SSRCMapEvents> {
+	/**
+	 * The underlying map.
+	 */
+	private readonly map: Map<number, VoiceUserData>;
+
+	public constructor() {
+		super();
+		this.map = new Map();
+	}
+
+	/**
+	 * Updates the map with new user data
+	 *
+	 * @param data The data to update with
+	 */
+	public update(data: VoiceUserData) {
+		const existing = this.map.get(data.audioSSRC);
+
+		const newValue = {
+			...this.map.get(data.audioSSRC),
+			...data,
+		};
+
+		this.map.set(data.audioSSRC, newValue);
+		if (!existing) this.emit('create', newValue);
+		this.emit('update', existing, newValue);
+	}
+
+	/**
+	 * Gets the stored voice data of a user.
+	 *
+	 * @param target The target, either their user id or audio SSRC
+	 */
+	public get(target: number | string) {
+		if (typeof target === 'number') {
+			return this.map.get(target);
+		}
+
+		for (const data of this.map.values()) {
+			if (data.userId === target) {
+				return data;
+			}
+		}
+
+		return undefined;
+	}
+
+	/**
+	 * Deletes the stored voice data about a user.
+	 *
+	 * @param target The target of the delete operation, either their audio SSRC or user id
+	 *
+	 * @returns The data that was deleted, if any
+	 */
+	public delete(target: number | string) {
+		if (typeof target === 'number') {
+			const existing = this.map.get(target);
+			if (existing) {
+				this.map.delete(target);
+				this.emit('delete', existing);
+			}
+			return existing;
+		}
+
+		for (const [audioSSRC, data] of this.map.entries()) {
+			if (data.userId === target) {
+				this.map.delete(audioSSRC);
+				this.emit('delete', data);
+				return data;
+			}
+		}
+
+		return undefined;
+	}
+}