import { IAuthenticator, ICache, IMessageRouter, SystemConfig } from '@citrineos/base';
import { ILogObj, Logger } from 'tslog';
export declare class WebsocketNetworkConnection {
    protected _cache: ICache;
    protected _config: SystemConfig;
    protected _logger: Logger<ILogObj>;
    private _identifierConnections;
    private _httpServersMap;
    private _authenticator;
    private _router;
    constructor(config: SystemConfig, cache: ICache, authenticator: IAuthenticator, router: IMessageRouter, logger?: Logger<ILogObj>);
    /**
     * Send a message to the charging station specified by the identifier.
     *
     * @param {string} identifier - The identifier of the client.
     * @param {string} message - The message to send.
     * @return {void} rejects the promise if message fails to send, otherwise returns void.
     */
    sendMessage(identifier: string, message: string): Promise<void>;
    shutdown(): Promise<void>;
    /**
     * Updates certificates for a specific server with the provided TLS key, certificate chain, and optional
     * root CA.
     *
     * @param {string} serverId - The ID of the server to update.
     * @param {string} tlsKey - The TLS key to set.
     * @param {string} tlsCertificateChain - The TLS certificate chain to set.
     * @param {string} [rootCA] - The root CA to set (optional).
     * @return {void} void
     */
    updateTlsCertificates(serverId: string, tlsKey: string, tlsCertificateChain: string, rootCA?: string): void;
    private _onHttpRequest;
    /**
     * Method to validate websocket upgrade requests and pass them to the socket server.
     *
     * @param {IncomingMessage} req - The request object.
     * @param {Duplex} socket - Websocket duplex stream.
     * @param {Buffer} head - Websocket buffer.
     * @param {WebSocketServer} wss - Websocket server.
     * @param {WebsocketServerConfig} websocketServerConfig - websocket server config.
     */
    private _upgradeRequest;
    /**
     * Utility function to reject websocket upgrade requests with 500 status code.
     * @param socket - Websocket duplex stream.
     */
    private _terminateConnectionInternalError;
    /**
     * Internal method to handle new client connection and ensures supported protocols are used.
     *
     * @param {Set<string>} protocols - The set of protocols to handle.
     * @param {IncomingMessage} req - The request object.
     * @param {string} wsServerProtocol - The websocket server protocol.
     * @return {boolean|string} - Returns the protocol version if successful, otherwise false.
     */
    private _handleProtocols;
    /**
     * Internal method to handle the connection event when a WebSocket connection is established.
     * This happens after successful protocol exchange with client.
     *
     * @param {WebSocket} ws - The WebSocket object representing the connection.
     * @param {number} pingInterval - The ping interval in seconds.
     * @param {IncomingMessage} req - The request object associated with the connection.
     * @return {void}
     */
    private _onConnection;
    /**
     * Internal method to register event listeners for the WebSocket connection.
     *
     * @param {string} identifier - The unique identifier for the connection.
     * @param {WebSocket} ws - The WebSocket object representing the connection.
     * @param {number} pingInterval - The ping interval in seconds.
     * @return {void} This function does not return anything.
     */
    private _registerWebsocketEvents;
    /**
     * Internal method to handle the incoming message from the websocket client.
     *
     * @param {string} identifier - The client identifier.
     * @param {string} message - The incoming message from the client.
     * @param {OCPPVersionType} protocol - The OCPP protocol version of the client, 'ocpp1.6' or 'ocpp2.0.1'.
     * @return {void} This function does not return anything.
     */
    private _onMessage;
    /**
     * Internal method to handle the error event for the WebSocket server.
     *
     * @param {WebSocketServer} wss - The WebSocket server instance.
     * @param {Error} error - The error object.
     * @return {void} This function does not return anything.
     */
    private _onError;
    /**
     * Internal method to handle the event when the WebSocketServer is closed.
     *
     * @param {WebSocketServer} wss - The WebSocketServer instance.
     * @return {void} This function does not return anything.
     */
    private _onClose;
    /**
     * Internal method to execute a ping operation on a WebSocket connection after a delay of 60 seconds.
     *
     * @param {string} identifier - The identifier of the client connection.
     * @param {WebSocket} ws - The WebSocket connection to ping.
     * @param {number} pingInterval - The ping interval in milliseconds.
     * @return {void} This function does not return anything.
     */
    private _ping;
    /**
     *
     * @param url Http upgrade request url used by charger
     * @returns Charger identifier
     */
    private _getClientIdFromUrl;
    private _generateServerOptions;
}