import { IUrl, IDatabaseAdapter } from "../interfaces/database.interface";
export interface ShortifyOptions {
    baseUrl: string;
    urlLength?: number;
    customUrlId?: string;
    expiresInDays?: number;
}
export interface ShortifyResult {
    originalUrl: string;
    shortUrl: string;
    urlId: string;
    expiresAt?: Date;
}
export declare class ShortenerService {
    private defaultUrlLength;
    private baseUrl;
    private dbAdapter;
    constructor(baseUrl: string, dbAdapter: IDatabaseAdapter);
    /**
     * Validate if a URL is properly formatted
     */
    private isValidUrl;
    /**
     * Generate a short URL ID
     */
    private generateUrlId;
    /**
     * Check if a URL ID already exists in the database
     * For performance, we use this to avoid duplicate URL IDs
     */
    private findExistingUrlId;
    /**
     * Shorten a URL
     */
    shorten(originalUrl: string, options?: Partial<ShortifyOptions>): Promise<ShortifyResult>;
    /**
     * Resolve a short URL to its original URL
     */
    resolve(urlId: string): Promise<string | null>;
    /**
     * Get URL stats
     */
    getUrlStats(urlId: string): Promise<Partial<IUrl> | null>;
    /**
     * Delete a shortened URL
     */
    deleteUrl(urlId: string): Promise<boolean>;
}