import Database from 'better-sqlite3';
/**
 * Comparison operators for WHERE clauses
 */
export type ComparisonOperator = '=' | '<>' | '>' | '>=' | '<' | '<=' | 'LIKE' | 'IN' | 'NOT IN' | 'IS NULL' | 'IS NOT NULL' | 'BETWEEN';
/**
 * WHERE condition
 */
export interface WhereCondition {
    /**
     * Field name
     */
    field: string;
    /**
     * Comparison operator
     */
    operator: ComparisonOperator;
    /**
     * Comparison value
     */
    value?: any;
}
/**
 * JOIN condition
 */
export interface JoinCondition {
    /**
     * Table to join
     */
    table: string;
    /**
     * Join type
     */
    type: 'INNER' | 'LEFT' | 'RIGHT' | 'FULL';
    /**
     * ON clause
     */
    on: string;
}
/**
 * ORDER BY condition
 */
export interface OrderCondition {
    /**
     * Field to order by
     */
    field: string;
    /**
     * Sort direction
     */
    direction: 'ASC' | 'DESC';
}
/**
 * SQL query builder for constructing complex queries
 */
export declare class QueryBuilder {
    private db;
    private tableName;
    private selectFields;
    private whereConditions;
    private orConditions;
    private joinConditions;
    private groupByFields;
    private havingConditions;
    private orderByConditions;
    private limitValue?;
    private offsetValue?;
    private params;
    /**
     * Creates a new QueryBuilder instance
     * @param db Database instance
     * @param tableName Table name
     */
    constructor(db: Database.Database, tableName: string);
    /**
     * Sets the fields to select
     * @param fields Field names
     * @returns this instance for chaining
     */
    select(...fields: string[]): QueryBuilder;
    /**
     * Adds a WHERE condition
     * @param field Field name
     * @param operator Comparison operator
     * @param value Comparison value
     * @returns this instance for chaining
     */
    where(field: string, operator: ComparisonOperator, value?: any): QueryBuilder;
    /**
     * Adds an AND condition
     * @param field Field name
     * @param operator Comparison operator
     * @param value Comparison value
     * @returns this instance for chaining
     */
    and(field: string, operator: ComparisonOperator, value?: any): QueryBuilder;
    /**
     * Adds an OR condition
     * @param conditions Callback for creating OR conditions
     * @returns this instance for chaining
     */
    or(conditions: (qb: QueryBuilder) => void): QueryBuilder;
    /**
     * Adds a grouped AND condition with parentheses
     * @param conditions Callback for creating grouped conditions
     * @returns this instance for chaining
     */
    andWhere(conditions: (qb: QueryBuilder) => void): QueryBuilder;
    /**
     * Adds a table join
     * @param table Table to join
     * @param type Join type
     * @param on ON clause
     * @returns this instance for chaining
     */
    join(table: string, type: 'INNER' | 'LEFT' | 'RIGHT' | 'FULL', on: string): QueryBuilder;
    /**
     * Adds an INNER JOIN
     * @param table Table to join
     * @param on ON clause
     * @returns this instance for chaining
     */
    innerJoin(table: string, on: string): QueryBuilder;
    /**
     * Adds a LEFT JOIN
     * @param table Table to join
     * @param on ON clause
     * @returns this instance for chaining
     */
    leftJoin(table: string, on: string): QueryBuilder;
    /**
     * Sets GROUP BY fields
     * @param fields Field names
     * @returns this instance for chaining
     */
    groupBy(...fields: string[]): QueryBuilder;
    /**
     * Adds a HAVING condition
     * @param field Field name
     * @param operator Comparison operator
     * @param value Comparison value
     * @returns this instance for chaining
     */
    having(field: string, operator: ComparisonOperator, value?: any): QueryBuilder;
    /**
     * Sets ORDER BY clause
     * @param field Field name
     * @param direction Sort direction
     * @returns this instance for chaining
     */
    orderBy(field: string, direction?: 'ASC' | 'DESC'): QueryBuilder;
    /**
     * Sets LIMIT clause
     * @param limit Maximum number of results
     * @returns this instance for chaining
     */
    limit(limit: number): QueryBuilder;
    /**
     * Sets OFFSET clause
     * @param offset Number of results to skip
     * @returns this instance for chaining
     */
    offset(offset: number): QueryBuilder;
    /**
     * Builds a WHERE condition string from conditions
     * @param conditions WHERE conditions
     * @returns WHERE condition string
     */
    private buildWhereConditionString;
    /**
     * Builds the complete SQL query
     * @returns SQL query and parameters
     */
    build(): {
        sql: string;
        params: any[];
    };
    /**
     * Executes the query and returns all results
     * @returns Query results
     */
    all<R = any>(): R[];
    /**
     * Executes the query and returns the first result
     * @returns First result or null if none
     */
    first<R = any>(): R | null;
    /**
     * Counts the number of matching records
     * @returns Record count
     */
    count(): number;
}