peerjs/lib/baseconnection.ts

import type { Peer } from "./peer";
import type { ServerMessage } from "./servermessage";
import type { ConnectionType } from "./enums";
import { BaseConnectionErrorType } from "./enums";
import { PeerError, type PromiseEvents } from "./peerError";
import EventEmitter from "eventemitter3";
import { EventEmitterWithPromise } from "./eventEmitterWithPromise";

export interface BaseConnectionEvents<
	ErrorType extends string = BaseConnectionErrorType,
> extends PromiseEvents<never, ErrorType> {
	/**
	 * Emitted when either you or the remote peer closes the connection.
	 *
	 * ```ts
	 * connection.on('close', () => { ... });
	 * ```
	 */
	close: () => void;
	/**
	 * ```ts
	 * connection.on('error', (error) => { ... });
	 * ```
	 */
	error: (error: PeerError<`${ErrorType}`>) => void;
	iceStateChanged: (state: RTCIceConnectionState) => void;
}

export interface IBaseConnection<
	SubClassEvents extends BaseConnectionEvents<
		BaseConnectionErrorType | ErrorType
	>,
	ErrorType extends string = never,
> extends EventEmitter<SubClassEvents> {
	readonly metadata: any;
	readonly connectionId: string;
	get type(): ConnectionType;
	/**
	 * The optional label passed in or assigned by PeerJS when the connection was initiated.
	 */
	label: string;
	/**
	 * Whether the media connection is active (e.g. your call has been answered).
	 * You can check this if you want to set a maximum wait time for a one-sided call.
	 */
	get open(): boolean;
	close(): void;
}

export abstract class BaseConnection<
		AwaitType extends EventEmitter<SubClassEvents>,
		SubClassEvents extends BaseConnectionEvents<
			BaseConnectionErrorType | ErrorType
		>,
		ErrorType extends string = never,
	>
	extends EventEmitterWithPromise<
		AwaitType,
		never,
		ErrorType | BaseConnectionErrorType,
		SubClassEvents
	>
	implements IBaseConnection<SubClassEvents, ErrorType>
{
	protected _open = false;

	/**
	 * Any type of metadata associated with the connection,
	 * passed in by whoever initiated the connection.
	 */
	readonly metadata: any;
	connectionId: string;

	peerConnection: RTCPeerConnection;
	dataChannel: RTCDataChannel;

	abstract get type(): ConnectionType;

	label: string;

	get open() {
		return this._open;
	}

	protected constructor(
		/**
		 * The ID of the peer on the other end of this connection.
		 */
		readonly peer: string,
		public provider: Peer,
		readonly options: any,
	) {
		super();

		this.metadata = options.metadata;
	}

	abstract close(): void;

	/**
	 * @internal
	 */
	abstract handleMessage(message: ServerMessage): void;

	/**
	 * Called by the Negotiator when the DataChannel is ready.
	 * @internal
	 * */
	abstract _initializeDataChannel(dc: RTCDataChannel): void;
}