import { IConfig } from '../types';
/**
 * Manages application configuration from multiple sources
 * Loads from .env files, environment variables and direct configuration
 * with priority handling and OS-specific paths
 */
export declare class ConfigManager {
    private config;
    /**
     * Required configuration parameters for the application to function
     * These must be provided or the validation will fail
     */
    private requiredEnvVars;
    /**
     * Creates a new configuration manager
     * @param directConfig Optional configuration values to override environment variables
     */
    constructor(directConfig?: Partial<IConfig>);
    /**
     * Sets a configuration value and updates dependent values
     * @param key Configuration key to set
     * @param value New value for the configuration key
     */
    set<K extends keyof IConfig>(key: K, value: IConfig[K]): void;
    /**
     * Builds a fully qualified domain name from subdomain and domain parts
     * @param subdomain Subdomain component
     * @param domain Domain component
     * @returns Formatted FQDN or empty string if insufficient parts
     */
    private constructFqdn;
    /**
     * Loads environment variables from multiple locations in priority order
     * Tries several common paths for .env files
     */
    private loadEnvironmentVariables;
    /**
     * Creates directories needed for logs and IP storage if they don't exist
     */
    private ensureDirectoriesExist;
    /**
     * Determines the appropriate log file path based on the current OS
     * @returns OS-specific default log path
     */
    private getDefaultLogPath;
    /**
     * Determines the appropriate IP storage file path based on the current OS
     * @returns OS-specific default path for storing the last known IP
     */
    private getDefaultIpStoragePath;
    /**
     * Validates that all required configuration parameters are present
     * @throws Error if required configuration is missing
     */
    validate(): void;
    /**
     * Gets a specific configuration value
     * @param key Configuration key to retrieve
     * @returns Value for the specified configuration key
     */
    get<K extends keyof IConfig>(key: K): IConfig[K];
    /**
     * Gets a copy of the entire configuration object
     * @returns Complete configuration object
     */
    getAll(): IConfig;
    /**
     * Checks if all required configuration exists
     * @returns True if all required config parameters are present and non-empty
     */
    configExists(): boolean;
}