import Database from 'better-sqlite3';
import { BaseEntity, TableInfo } from './BaseEntity';
/**
 * Query options for finding entities
 */
export interface QueryOptions {
    /**
     * WHERE conditions as key-value pairs
     */
    where?: {
        [key: string]: any;
    };
    /**
     * ORDER BY clause (e.g., 'id DESC')
     */
    orderBy?: string;
    /**
     * Maximum number of results to return
     */
    limit?: number;
    /**
     * Number of results to skip
     */
    offset?: number;
}
/**
 * Base service class for CRUD operations on entities
 */
export declare class BaseService<T extends object> {
    protected db: Database.Database;
    protected entityClass: new () => T & BaseEntity;
    protected tableInfo: TableInfo;
    /**
     * Creates a new service for the specified entity
     * @param db Database instance
     * @param entityClass Entity class
     */
    constructor(db: Database.Database, entityClass: any);
    /**
     * Inserts a new entity into the database
     * @param entity Entity to insert
     * @returns ID of the inserted entity
     */
    insert(entity: Partial<T>): number;
    /**
     * Inserts multiple entities in a single transaction
     * @param entities Array of entities to insert
     */
    batchInsert(entities: Partial<T>[]): void;
    /**
     * Retrieves an entity by its ID
     * @param id Entity ID
     * @returns Entity or null if not found
     */
    getById(id: number | string): T | null;
    /**
     * Finds entities matching the specified criteria
     * @param options Query options
     * @returns Array of matching entities
     */
    find(options?: QueryOptions): T[];
    /**
     * Finds a single entity matching the specified criteria
     * @param options Query options
     * @returns Matching entity or null if not found
     */
    findOne(options?: QueryOptions): T | null;
    /**
     * Counts entities matching the specified criteria
     * @param options Query options
     * @returns Count of matching entities
     */
    count(options?: QueryOptions): number;
    /**
     * Updates an entity in the database
     * @param entity Entity data to update
     * @param whereCondition Optional WHERE condition (defaults to primary key)
     * @returns Number of updated rows
     */
    update(entity: Partial<T>, whereCondition?: {
        [key: string]: any;
    }): number;
    /**
     * Deletes entities matching the specified condition
     * @param whereCondition WHERE condition
     * @returns Number of deleted rows
     */
    delete(whereCondition: {
        [key: string]: any;
    }): number;
    /**
     * Deletes an entity by its ID
     * @param id Entity ID
     * @returns Number of deleted rows
     */
    deleteById(id: number | string): number;
    /**
     * Executes a custom SQL query
     * @param sql SQL statement
     * @param params Query parameters
     * @returns Query results
     */
    query<R = any>(sql: string, params?: any[]): R[];
    /**
     * Executes a custom SQL statement
     * @param sql SQL statement
     * @param params Statement parameters
     * @returns Statement result
     */
    execute(sql: string, params?: any[]): Database.RunResult;
}