import type { FilesystemProvider } from "../infra/filesystem-provider.js";
import type { StoredSnapshot } from "./types.js";
/** Snapshot store contract. Implementations may be filesystem, memory, or external. */
export interface SnapshotStore {
    /** Persist a snapshot and its session. Immutable: existing ids are rejected. */
    save(stored: StoredSnapshot): Promise<void>;
    /** Retrieve a snapshot by id. */
    get(snapshotId: string): Promise<StoredSnapshot | undefined>;
    /** List snapshots, optionally filtered to a single lineage. */
    list(lineageId?: string): Promise<StoredSnapshot[]>;
}
export declare class InMemorySnapshotStore implements SnapshotStore {
    private snapshots;
    save(stored: StoredSnapshot): Promise<void>;
    get(snapshotId: string): Promise<StoredSnapshot | undefined>;
    list(lineageId?: string): Promise<StoredSnapshot[]>;
    private clone;
}
export declare function createInMemorySnapshotStore(): SnapshotStore;
export declare class FileSystemSnapshotStore implements SnapshotStore {
    private dir;
    private readonly fs;
    constructor(dir: string, fsProvider?: FilesystemProvider);
    save(stored: StoredSnapshot): Promise<void>;
    get(snapshotId: string): Promise<StoredSnapshot | undefined>;
    list(lineageId?: string): Promise<StoredSnapshot[]>;
    /**
     * Parse, migrate, and certify a stored snapshot record. The ancestor
     * chain is verified first: a snapshot with a lineage parent can only
     * be certified against its parent's signature, so a tampered ancestor
     * invalidates every descendant. Tampered or malformed files are
     * rejected loudly.
     */
    private loadVerified;
    private fileName;
}
export declare function createFileSystemSnapshotStore(dir: string): SnapshotStore;