import { DotenvConfigOptions } from 'dotenv';
/**
 * Add a couple of options to the default config options' interface.
 */
export interface DotenvConfig extends DotenvConfigOptions {
    cwd?: string;
    glob?: string;
    defaultNodeEnv?: string;
}
export interface ModuleConfig {
    [key: string]: any;
}
export interface Config {
    [key: string]: ModuleConfig;
}
export declare type CustomHelper = {
    [key: string]: (...args: any[]) => any;
};
export declare class ConfigService {
    [key: string]: Config | CustomHelper | ((...args: any[]) => any) | any;
    private static config;
    private readonly helpers;
    protected static defaultGlob: string;
    static srcPath?: string;
    /**
     * @param {Config} config
     */
    constructor(config?: Config);
    /**
     * Load configuration from file system
     * @param glob string
     * @param {DotenvConfig} options
     * @returns {Promise<any>}
     */
    static load(globOrOptions?: string | DotenvConfig | false, options?: DotenvConfig | false): Promise<ConfigService>;
    /**
     * Load config synchronously
     * @param {string} glob
     * @param {DotenvConfig | false} options
     */
    static loadSync(glob: string, options?: DotenvConfig | false): ConfigService;
    /**
     * Get the param or use default
     *
     * @param {String} key
     * @param {any} value default
     * @returns {any|undefined}
     */
    static get(param: string | string[], value?: any): any;
    /**
     * Get the param or use default
     *
     * @param param
     * @param {any} value default
     * @returns {any}
     */
    get(param: string | string[], value?: any): any;
    /**
     * Set config value at runtime
     * @param {string} param
     * @param value
     * @returns {Config}
     */
    set(param: string | string[], value?: any): Config;
    /**
     * Check the param exists
     *
     * @param param
     * @returns {boolean}
     */
    has(param: string | string[]): boolean;
    /**
     * Merge configuration
     * @param glob
     * @param options
     */
    merge(glob: string, options?: DotenvConfig): Promise<void>;
    /**
     * Merge configuration synchronously
     * @param {string} glob
     * @param {DotenvConfig} options
     * @returns {ConfigService}
     */
    mergeSync(glob: string, options?: DotenvConfig): ConfigService;
    /**
     * @param {string} name
     * @param {CustomHelper} fn
     * @returns {ConfigService}
     */
    registerHelper(name: string, fn: (...args: any[]) => any): ConfigService;
    /**
     * @param {string} dir
     * @returns {string}
     */
    static root(dir?: string): string;
    /**
     * @param {string} dir
     * @returns {string}
     */
    static src(dir?: string): string;
    /**
     * Resolves and stores sources directory for application.
     * @param {string} startPath
     *  The path for search starting. Can be any path under app sources path.
     */
    static resolveSrcPath(startPath: string): typeof ConfigService;
    /**
     * @param {string | string[]} glob
     * @param {DotenvConfig | false} options
     * @returns {Promise<Config>}
     */
    protected static loadConfigAsync(glob: string, options?: DotenvConfig | false): Promise<Config>;
    /**
     * Load config synchronously
     * @param {string} glob
     * @param {DotenvConfig | false} options
     * @returns {Config}
     */
    protected static loadConfigSync(glob: string, options?: DotenvConfig | false): Config;
    /**
     * Config graph from an array of paths
     * @param configPaths
     * @returns {any}
     */
    protected static configGraph(configPaths: string[]): {};
    /**
     * @param config
     * @returns {string}
     */
    protected bindCustomHelpers(config: any): any;
    /**
     * Get config name from a file path
     * @param {string} file
     * @returns {string}
     */
    protected static getConfigName(file: string): string;
    /**
     * Loads env variables via dotenv.
     * @param {DotenvConfig | false} options
     */
    protected static loadEnv(options?: DotenvConfig | false): void;
    /**
     * Default dotenv config point to a .env
     * on the cwd path
     * @returns {{path: string}}
     */
    protected static defaultDotenvConfig(): {
        cwd: string;
        defaultNodeEnv: string;
    };
}