BP_REST_Topics_Actions_Endpoint::rest_update_subscribe( integer $topic_id, boolean $value, integer $user_id )

	protected function rest_update_subscribe( $topic_id, $value, $user_id ) {
		if ( ! bbp_is_subscriptions_active() ) {
			return new WP_Error(
				'bp_rest_bbp_topic_action_disabled',
				__( 'Subscriptions are no longer active.', 'buddyboss' ),
				array(
					'status' => 404,
				)
			);
		}

		// Bail if user cannot add subscription for this user.
		if ( ! current_user_can( 'edit_user', $user_id ) ) {
			return new WP_Error(
				'bp_rest_authorization_required',
				__( 'You do not have permission to do this.', 'buddyboss' ),
				array(
					'status' => 404,
				)
			);
		}

		$status     = true;
		$subscribed = bbp_is_user_subscribed( $user_id, $topic_id );

		// Subscribed and unsubscribing.
		if ( true === $subscribed && empty( $value ) ) {
			$status = bbp_remove_user_subscription( $user_id, $topic_id );

			// Not subscribed and subscribing.
		} elseif ( false === $subscribed && ! empty( $value ) ) {
			$status = bbp_add_user_subscription( $user_id, $topic_id );
		}

		return $status;
	}