/**
 * JSONL-backed retain queue for buffering failed HTTP retains.
 *
 * When the remote Hindsight API is unreachable, retain requests are stashed
 * in a local JSONL file and flushed later. Only used in external API mode —
 * the local daemon handles its own persistence.
 *
 * Zero runtime dependencies; uses only Node built-ins.
 */
/** The subset of a retain payload the queue needs to persist and replay. */
export interface QueuedRetainPayload {
    content: string;
    documentId?: string;
    metadata?: Record<string, unknown>;
    tags?: string[];
    updateMode?: "replace" | "append";
}
export interface QueuedRetain {
    id: string;
    bankId: string;
    content: string;
    documentId: string;
    metadata: Record<string, unknown>;
    tags?: string[];
    updateMode?: "replace" | "append";
    createdAt: string;
}
export interface RetainQueueOptions {
    /** Path to the JSONL queue file. The parent directory must already exist. */
    filePath: string;
    /** Max age in ms for queued items. `-1` (default) keeps items forever. */
    maxAgeMs?: number;
}
export declare class RetainQueue {
    private readonly filePath;
    private readonly maxAgeMs;
    private cachedSize;
    constructor(opts: RetainQueueOptions);
    /** Append a failed retain for later delivery. */
    enqueue(bankId: string, request: QueuedRetainPayload, metadata?: Record<string, unknown>): void;
    /** Get up to `limit` oldest pending items (FIFO). */
    peek(limit?: number): QueuedRetain[];
    /** Remove a single item by id. */
    remove(id: string): void;
    /** Remove multiple items by id in a single file rewrite. */
    removeMany(ids: string[]): void;
    /** Number of items waiting (cached, O(1)). */
    size(): number;
    /** Drop items older than `maxAgeMs`. No-op when `maxAgeMs < 0`. */
    cleanup(): number;
    /** No-op — kept for API symmetry with DB-backed queues. */
    close(): void;
    private readAll;
    /** Atomically rewrite the file with the given items. */
    private writeAll;
}