import { Transform } from 'node:stream';
import type { TransformCallback } from 'node:stream';
export declare class GeminiSseNormalizer extends Transform {
    private decoder;
    private buffer;
    private lastDonePayload;
    private eventCounter;
    private chunkCounter;
    private processedEventCounter;
    private capturedEvents;
    private antigravitySessionId;
    private antigravityAliasKey;
    private enableAntigravitySignatureCache;
    constructor(options?: {
        sessionId?: string;
        aliasKey?: string;
        enableAntigravitySignatureCache?: boolean;
    });
    _transform(chunk: unknown, _encoding: BufferEncoding, callback: TransformCallback): void;
    _flush(callback: TransformCallback): void;
    private processBuffered;
    private processEvent;
    private emitCandidateParts;
    private pushEvent;
}