/**
 * One live attachment to a subagent conversation: a transcript store seeded
 * from the child's durable log and then fed by the process-local event and
 * stream buses in real time. The parent's own store is never touched.
 *
 * @module @deepseek-ai/dsh-code/session/attach
 */
import type { SessionEvent } from '@deepseek-ai/dsh-session';
import { type TranscriptStore } from './store.ts';
/** The bus surfaces one attachment reads; the runner wires these to ctx. */
export interface SubagentAttachmentServices {
    /** Seed: the child's full durable event log, oldest first. */
    load(id: string, signal?: AbortSignal): Promise<readonly SessionEvent[]>;
    /** Durable events for exactly this child session, live. */
    subscribeEvents(id: string, onEvent: (event: SessionEvent) => void): () => void;
    /** Token stream frames for exactly this child agent, live. */
    subscribeStream(id: string, onFrame: (frame: Parameters<TranscriptStore['applyStreamFrame']>[0]) => void): () => void;
}
/** A live child view handed to the App while attached. */
export interface SubagentAttachment {
    readonly id: string;
    readonly label: string;
    readonly store: TranscriptStore;
    /** Whether the durable seed has landed (frames are held back until then). */
    seeded(): boolean;
    /** Drop the bus subscriptions; the store freezes at its last state. */
    dispose(): void;
}
/** An inert empty store keeps the App's external-store hook unconditional. */
export declare const EMPTY_ATTACH_STORE: TranscriptStore;
/**
 * Attach to one subagent conversation.
 *
 * Ordering contract: durable events carry a per-session sequence, so the seed
 * sets a watermark and live events at or below it are dropped as duplicates;
 * stream frames are held until the seed lands so a frame whose settlement
 * already arrived cannot resurrect a stale tail.
 */
export declare function createSubagentAttachment(services: SubagentAttachmentServices, id: string, label: string): SubagentAttachment;