import { Worker } from "node:worker_threads";
import { IBaseSqliteDialectConfig, IGenericSqlite, Promisable } from "kysely-generic-sqlite";
import { GenericSqliteWorkerDialect, WorkerRequestHandler } from "kysely-generic-sqlite/worker";
import Database, { Options } from "better-sqlite3";

//#region src/worker/utils.d.ts
/**
* Factory signature for creating a `better-sqlite3` Database.
*/
type CreateDatabaseFn = (filename?: string | Buffer, options?: Database.Options) => Promisable<Database.Database>;
/**
* Default database factory — creates a new `better-sqlite3` Database instance.
*/
declare const defaultCreateDatabaseFn: CreateDatabaseFn;
/**
* Handle worker messages, with optional custom message handler.
*
* Uses {@link defaultCreateDatabaseFn} by default.
*
* @example
* In `worker.ts`:
* ```ts
* import { createOnMessageCallback, defaultCreateDatabaseFn } from 'kysely-sqlite-worker'
*
* createOnMessageCallback(
*   (fileName, options) => {
*     const db = defaultCreateDatabaseFn(fileName, options)
*     db.loadExtension(...)
*     return db
*   },
*   (executor, { type, payload }) => {
*     if (type === 'export') {
*       return executor.db.export()
*     }
*     throw new Error(`Unknown worker request: ${type}`)
*   },
* )
* ```
*/
declare function createOnMessageCallback(create: CreateDatabaseFn, custom?: WorkerRequestHandler<Database.Database>): void;
/**
* Build a {@link IGenericSqlite} executor from a `better-sqlite3` Database.
*/
declare function createSqliteExecutor(db: Database.Database): IGenericSqlite<Database.Database>;
//#endregion
//#region src/index.d.ts
/**
* Configuration for {@link SqliteWorkerDialect}.
*/
interface SqliteWorkerDialectConfig extends IBaseSqliteDialectConfig {
  /**
  * SQLite database file path or an existing buffer.
  */
  source: string | Buffer | (() => Promisable<string | Buffer>);
  /**
  * Options forwarded to the `better-sqlite3` constructor.
  */
  dbOption?: Options;
  /**
  * Path to a custom worker script.
  *
  * When omitted the built-in worker is used.
  */
  workerPath?: string;
}
/**
* SQLite dialect for Node.js using `better-sqlite3` running in a worker thread.
*/
declare class SqliteWorkerDialect extends GenericSqliteWorkerDialect<Worker, {}> {
  /**
  * @param config - {@link SqliteWorkerDialectConfig}
  */
  constructor(config: SqliteWorkerDialectConfig);
}
//#endregion
export { CreateDatabaseFn, SqliteWorkerDialect, SqliteWorkerDialectConfig, createOnMessageCallback, createSqliteExecutor, defaultCreateDatabaseFn };