export declare type Range<T> = {
    start?: T;
    end?: T;
};
export declare class GoogleSheetsService {
    private CLIENT_SECRET;
    private CLIENT_ID;
    private REFRESH_TOKEN;
    private spreadsheetId;
    private options?;
    private http;
    private MAX_VALUE_LENGTH;
    constructor(CLIENT_SECRET: string, CLIENT_ID: string, REFRESH_TOKEN: string, spreadsheetId: string, options?: {
        MAX_VALUE_LENGTH?: number | undefined;
        LAST_COLUMN?: string | undefined;
    } | undefined);
    static mountRange(columns: Range<string>, rows: Range<number>, sheet?: string): string;
    private sanitizeValue;
    private getToken;
    appendRow(values: Array<any>, anchorColumn?: string, sheet?: string): Promise<any>;
    getRows(columns: Range<string>, rows: Range<number>, sheet?: string): Promise<Array<Array<string>>>;
    freezeRows(sheetId: number, rows?: number): Promise<any>;
    upsertSheet(title: string, headers?: Array<string>, anchorColumn?: string): Promise<boolean>;
}