/**
 * hmem v2 — full-text search over the contentless FTS5 index (L0095 pattern).
 *
 * The `fts` virtual table stores no content; triggers (see schema-v2.sql) keep it
 * in sync and `fts_rowid_map` maps each FTS rowid back to a source `(root_uid,
 * node_uid)`. node_uid IS NULL ⇒ the hit is an entry's own level_1; otherwise it
 * is a node's content. Soft-deleted rows stay indexed (soft-delete is a column
 * update, not a row DELETE), so they are filtered out here at query time.
 */
import type Database from 'better-sqlite3';
export interface SearchHit {
    root_uid: string;
    node_uid: string | null;
}
export interface FtsApi {
    search(query: string, limit?: number): SearchHit[];
}
/**
 * Build a safe FTS5 MATCH expression: each whitespace-separated term becomes a
 * quoted phrase (internal double-quotes doubled), joined by spaces → implicit AND.
 * Quoting neutralizes FTS5 operators so arbitrary user input cannot inject syntax.
 */
export declare function toMatchExpr(query: string): string | null;
export declare function createFtsApi(db: Database.Database): FtsApi;