import { EventHandlers } from "./types";
import { Context, ContextualLoggedClass } from "@decaf-ts/core";
export type ServerEventConnectorHeaders = Record<string, string> | (() => Record<string, string> | Promise<Record<string, string>>);
export declare class ServerEventConnector extends ContextualLoggedClass<Context<any>> {
    private readonly url;
    private readonly headers?;
    private static readonly cache;
    static get(url: string): ServerEventConnector;
    static open(url: string, headers?: ServerEventConnectorHeaders): ServerEventConnector;
    static close(url: string): void;
    private static parseReceivedEvent;
    /** Shared connection state (cached singleton instance). */
    private es?;
    private controller?;
    private listeners;
    constructor(url: string, headers?: ServerEventConnectorHeaders | undefined);
    isOpen(): boolean;
    protected getHeaders(): Promise<ServerEventConnectorHeaders>;
    close(force?: boolean): void;
    /**
     * Increments refCount and ensures EventSource is created.
     * This method must be called only on the shared singleton instance.
     */
    private startListening;
    addListener(handlers: EventHandlers): () => void;
    removeListener(handlers: EventHandlers): void;
}