import { SseData } from '../types/entity';
import type { ConnectionClosedPayload } from '../types/entity';
interface SseOptions {
    url: string;
    token: string;
    retryInterval?: number;
    connectTimeout?: number;
    maxRetries?: number;
    debug?: boolean;
    onMessage?: (response: SseData) => void;
    onReconnectSuccess?: () => void;
    onConnectionClosed?: (payload: ConnectionClosedPayload) => void;
    onMaxRetriesReached?: () => void;
    onConnectionChange?: (isConnected: boolean) => void;
}
declare class SseClient {
    private url;
    private token;
    private eventSource;
    private reconnectAttempts;
    private maxReconnectAttempts;
    private reconnectTimeout;
    private connectTimeout;
    private reconnectTimer;
    private handlers;
    private connected;
    private onMessageCallback?;
    private onReconnectSuccessCallback?;
    private onConnectionClosedCallback?;
    private onMaxRetriesReachedCallback?;
    private onConnectionChangeCallback?;
    private isDestroyed;
    private debug;
    constructor(options: SseOptions);
    private debugLog;
    private debugError;
    private debugWarn;
    private removeAllEventListeners;
    private _openHandler;
    private _errorHandler;
    private _messageHandler;
    private _customHandlers;
    private connectTimeoutRef;
    subscribe(type: string, handler: Function): void;
    connect(): Promise<string>;
    private notifyConnectionClosed;
    private handleReconnect;
    private cleanup;
    unsubscribe(): void;
    destroySse(): void;
    close(): void;
    isConnected(): boolean;
    /**
     * 发送消息到服务器
     * SSE 是单向通信协议，不支持客户端向服务器发送消息
     * @param data 要发送的数据
     * @throws Error 总是抛出错误，因为 SSE 不支持发送
     * @returns 永远不会返回（总是抛出错误）
     */
    send(data: string | object | ArrayBuffer | Blob | ArrayBufferView): boolean;
}
export default SseClient;