[NEW] Enable outbound calling for EE (#25843) (#25960)

* Clickup Task: https://app.clickup.com/t/22bmce2
Description: Creating EE structure for outbound dialing.
Refactored VoIPUser.ts and made necessary fields protected.
Created VoIPUser or EEVoipClient based on the licensing in SimpleVoipUser
Made necessary changes for using the voip client.

* Clickup Task: https://app.clickup.com/t/22bmce2
Description: Adding missing file.

* Clickup Task: https://app.clickup.com/t/22bmce2
Description: Connector changes for detecting the outbound call.

* Clickup Task: https://app.clickup.com/t/22bmce2
Description: Handling review comments.<!-- This is a pull request template, you do not need to uncomment or remove the comments, they won't show up in the PR text. -->

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  Doc: For documentation
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## Issue(s)
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Co-authored-by: amolghode1981 <86001342+amolghode1981@users.noreply.github.com>
Co-authored-by: Murtaza Patrawala <34130764+murtaza98@users.noreply.github.com>
Co-authored-by: Aleksander Nicacio da Silva <6494543+aleksandernsilva@users.noreply.github.com>
Co-authored-by: Tiago Evangelista Pinto <17487063+tiagoevanp@users.noreply.github.com>
Co-authored-by: Guilherme Gazzo <5263975+ggazzo@users.noreply.github.com>

apps/meteor/client/contexts/CallContext.ts

@@ -17,6 +17,7 @@ type CallContextEnabled = {
 	ready: unknown;
 };
 type CallContextReady = {
+	canMakeCall: boolean;
 	enabled: true;
 	ready: true;
 	voipClient: VoIPUser;

apps/meteor/client/lib/voip/VoIPUser.ts

@@ -47,8 +47,6 @@ export class VoIPUser extends Emitter<VoipEvents> {
 		enableVideo: false,
 	};
 
-	private session: Session | undefined;
-
 	private remoteStream: Stream | undefined;
 
 	userAgentOptions: UserAgentOptions = {};
@@ -59,12 +57,6 @@ export class VoIPUser extends Emitter<VoipEvents> {
 
 	mediaStreamRendered?: IMediaStreamRenderer;
 
-	private _callState: CallStates = 'INITIAL';
-
-	private _callerInfo: ICallerInfo | undefined;
-
-	private _userState: UserState = UserState.IDLE;
-
 	private _connectionState: ConnectionState = 'INITIAL';
 
 	private _held = false;
@@ -89,6 +81,24 @@ export class VoIPUser extends Emitter<VoipEvents> {
 
 	private attemptRegistration = false;
 
+	protected session: Session | undefined;
+
+	protected _callState: CallStates = 'INITIAL';
+
+	protected _callerInfo: ICallerInfo | undefined;
+
+	protected _userState: UserState = UserState.IDLE;
+
+	protected _opInProgress: Operation = Operation.OP_NONE;
+
+	get operationInProgress(): Operation {
+		return this._opInProgress;
+	}
+
+	get userState(): UserState | undefined {
+		return this._userState;
+	}
+
 	constructor(private readonly config: VoIPUserConfiguration, mediaRenderer?: IMediaStreamRenderer) {
 		super();
 		this.mediaStreamRendered = mediaRenderer;
@@ -116,7 +126,7 @@ export class VoIPUser extends Emitter<VoipEvents> {
 			server: this.config.webSocketURI,
 			connectionTimeout: 100, // Replace this with config
 			keepAliveInterval: 20,
-			// traceSip: true
+			// traceSip: true,
 		};
 		const sdpFactoryOptions = {
 			iceGatheringTimeout: 10,
@@ -242,16 +252,6 @@ export class VoIPUser extends Emitter<VoipEvents> {
 		};
 	}
 
-	private _opInProgress: Operation = Operation.OP_NONE;
-
-	get operationInProgress(): Operation {
-		return this._opInProgress;
-	}
-
-	get userState(): UserState | undefined {
-		return this._userState;
-	}
-
 	/* Media Stream functions begin */
 	/** The local media stream. Undefined if call not answered. */
 	get localMediaStream(): MediaStream | undefined {
@@ -322,7 +322,7 @@ export class VoIPUser extends Emitter<VoipEvents> {
 	 * This class handles such session state changes and takes necessary actions.
 	 */
 
-	private setupSessionEventHandlers(session: Session): void {
+	protected setupSessionEventHandlers(session: Session): void {
 		this.session?.stateChange.addListener((state: SessionState) => {
 			if (this.session !== session) {
 				return; // if our session has changed, just return
@@ -331,12 +331,32 @@ export class VoIPUser extends Emitter<VoipEvents> {
 				case SessionState.Initial:
 					break;
 				case SessionState.Establishing:
+					this.emit('ringing', { userState: this._userState, callInfo: this._callerInfo });
 					break;
 				case SessionState.Established:
+					if (this._userState === UserState.UAC) {
+						/**
+						 * We need to decide about user-state ANSWER-RECEIVED for outbound.
+						 * This state is there for the symmetry of ANSWER-SENT.
+						 * ANSWER-SENT occurs when there is incoming invite. So then the UA
+						 * accepts a call, it sends the answer and state becomes ANSWER-SENT.
+						 * The call gets established only when the remote party sends ACK.
+						 *
+						 * But in case of UAC where the invite is sent out, there is no intermediate
+						 * state where the UA can be in ANSWER-RECEIVED. As soon this UA receives the answer,
+						 * it sends ack and changes the SessionState to established.
+						 *
+						 * So we do not have an actual state transitions from ANSWER-RECEIVED to IN-CALL.
+						 *
+						 * Nevertheless, this state is just added to maintain the symmetry. This can be safely removed.
+						 *
+						 * */
+						this._callState = 'ANSWER_RECEIVED';
+					}
 					this._opInProgress = Operation.OP_NONE;
-					this._callState = 'IN_CALL';
 					this.setupRemoteMedia();
-					this.emit('callestablished');
+					this._callState = 'IN_CALL';
+					this.emit('callestablished', { userState: this._userState, callInfo: this._callerInfo });
 					this.emit('stateChanged');
 					break;
 				case SessionState.Terminating:
@@ -633,6 +653,18 @@ export class VoIPUser extends Emitter<VoipEvents> {
 		throw new Error('Something went wrong');
 	}
 
+	/* Helper routines for checking call actions BEGIN */
+
+	private canRejectCall(): boolean {
+		return ['OFFER_RECEIVED', 'OFFER_SENT'].includes(this._callState);
+	}
+
+	private canEndOrHoldCall(): boolean {
+		return ['ANSWER_SENT', 'ANSWER_RECEIVED', 'IN_CALL', 'ON_HOLD'].includes(this._callState);
+	}
+
+	/* Helper routines for checking call actions END */
+
 	/**
 	 * Public method called from outside to reject a call.
 	 * @remarks
@@ -641,7 +673,7 @@ export class VoIPUser extends Emitter<VoipEvents> {
 		if (!this.session) {
 			throw new Error('Session does not exist.');
 		}
-		if (this._callState !== 'OFFER_RECEIVED') {
+		if (!this.canRejectCall()) {
 			throw new Error(`Incorrect call State = ${this.callState}`);
 		}
 		if (!(this.session instanceof Invitation)) {
@@ -658,7 +690,7 @@ export class VoIPUser extends Emitter<VoipEvents> {
 		if (!this.session) {
 			throw new Error('Session does not exist.');
 		}
-		if (this._callState !== 'ANSWER_SENT' && this._callState !== 'IN_CALL' && this._callState !== 'ON_HOLD') {
+		if (!this.canEndOrHoldCall()) {
 			throw new Error(`Incorrect call State = ${this.callState}`);
 		}
 
@@ -708,7 +740,7 @@ export class VoIPUser extends Emitter<VoipEvents> {
 		if (!this.session) {
 			throw new Error('Session does not exist.');
 		}
-		if (this._callState !== 'ANSWER_SENT' && this._callState !== 'IN_CALL' && this._callState !== 'ON_HOLD') {
+		if (!this.canEndOrHoldCall()) {
 			throw new Error(`Incorrect call State = ${this.callState}`);
 		}
 		this.handleHoldUnhold(holdState);
@@ -966,4 +998,9 @@ export class VoIPUser extends Emitter<VoipEvents> {
 			},
 		});
 	}
+
+	// eslint-disable-next-line @typescript-eslint/no-unused-vars
+	async makeCall(_callee: string, _mediaRenderer?: IMediaStreamRenderer): Promise<void> {
+		throw new Error('Not implemented');
+	}
 }