import { MemoizeOptions } from '../flow-control/index.ts';
import type { PathLeaves, PathValue } from '../types.ts';
/**
 * Coerces string values in an object to their appropriate types.
 * Converts "true"/"false" to booleans, numeric strings to numbers, etc.
 * Recursively processes nested objects.
 *
 * IMPORTANT: This function mutates the input object in place.
 *
 * INTENTION: This is a best-effort coercion based on common string patterns.
 * It does not handle all edge cases and should be used with caution. The goal
 * is to convert typical string representations of booleans and numbers to their
 * actual types, while leaving other strings unchanged.
 *
 * USE CASE: Parsing environment variables or other flatmap configuration objects.
 *
 * @param obj The object whose values should be coerced (mutated in place).
 * @param opts Optional configuration options
 * @param opts.parseUnits Optional flag to parse unit values like '5m', '10mb'. Default is false.
 * @param opts.skipConversion Optional function to skip conversion for specific keys. Default is to convert all keys.
 *
 * @example
 * const config = {
 *     debug: 'true',
 *     port: '3000',
 *     nested: {
 *         enabled: 'false',
 *         retries: '5'
 *     }
 * };
 *
 * castValuesToTypes(config);
 *
 * console.log(config);
 * // {
 * //     debug: true,
 * //     port: 3000,
 * //     nested: {
 * //         enabled: false,
 * //         retries: 5
 * //     }
 * // }
 *
 * @example
 * const config = {
 *     timeout: '5m',
 *     maxUploadSize: '10mb',
 *     debug: 'true'
 * };
 *
 * castValuesToTypes(config, { parseUnits: true });
 *
 * console.log(config);
 * // {
 * //     timeout: 300000,  // 5 minutes in milliseconds
 * //     maxUploadSize: 10485760,  // 10 megabytes in bytes
 * //     debug: true
 * // }
 *
 * @example
 * const config = {
 *     apiKey: '12345',
 *     port: '3000'
 * };
 *
 * // Skip conversion for apiKey (keep it as string)
 * castValuesToTypes(config, {
 *     skipConversion: (key) => key.toLowerCase().includes('key')
 * });
 *
 * console.log(config);
 * // {
 * //     apiKey: '12345',  // Kept as string
 * //     port: 3000        // Converted to number
 * // }
 */
export declare const castValuesToTypes: (obj: object, opts?: {
    parseUnits?: boolean;
    skipConversion?: ((key: string, value: unknown) => boolean) | undefined;
}) => void;
export type MakeNestedConfigOpts = {
    filter?: (key: string, value: string) => boolean;
    skipConversion?: (key: string, value: unknown) => boolean;
    separator?: string;
    stripPrefix?: string | number;
    forceAllCapToLower?: boolean;
    parseUnits?: boolean;
    memoizeOpts?: false | MemoizeOptions<any>;
};
/**
 * Loads the flatmap variables and returns a config object.
 * Coerces values to the correct types based on guessing from
 * the value itself. For example, if the value is "true", it will be
 * converted to a boolean true, if it's "123", it will be converted
 * to a number 123, etc.
 *
 * @param flatConfig The flatmap configuration object (e.g. process.env)
 * @param opts Optional options object
 * @param opts.filter Optional filter function to include/exclude specific keys. Default is to include all keys.
 * @param opts.forceAllCapToLower Optional flag to force all-caps keys to lowercase. Default is true.
 * @param opts.separator Optional string to use as a separator for nested keys. Default is "_"
 * @param opts.stripPrefix Optional prefix to strip from keys. Can be a string (e.g., "APP_") or number of characters (e.g., 4). Default is undefined (no stripping).
 * @param opts.parseUnits Optional flag to parse unit values like '5m', '10mb'. Default is false.
 * @param opts.skipConversion Optional function to skip conversion for specific keys. Default is to convert all keys.
 * @param opts.memoizeOpts Optional memoization options for caching the config. Default is false (no memoization).
 *
 * @returns The full configuration object.
 *
 * @example
 * // Assuming process.env contains:
 * // {
 * //     APP_DB_HOST: 'localhost',
 * //     APP_DB_PORT: '5432',
 * //     APP_DEBUG: 'true',
 * //     APP_FEATURE_X_ENABLED: 'false'
 * //     APP_WORKER_EMAILS_maxRunsPerMin: '100'
 * //     APP_WORKER_EMAILS_networkTimeoutMs: '100'
 * // }
 *
 * const config = makeNestedConfig(process.env, {
 *     filter: (key) => key.startsWith('APP_'),
 *     stripPrefix: 'APP_',  // Strip the APP_ prefix from all keys
 *     forceAllCapToLower: true,
 *     separator: '_',
 *     memoizeOpts: { ttl: 60000 } // Cache for 60 seconds
 * });
 *
 * console.log(config());
 * // {
 * //     db: {
 * //         host: 'localhost',
 * //         port: 5432
 * //     },
 * //     debug: true,
 * //     feature: {
 * //         x: {
 * //             enabled: false
 * //         }
 * //     },
 * //     worker: {
 * //         emails: {
 * //             maxRunsPerMin: 100,
 * //             networkTimeoutMs: 100
 * //         }
 * //     }
 * // }
 *
 * @example
 * // Using a custom separator
 * // Assuming process.env contains:
 * // {
 * //     APP_DB__HOST: 'localhost',
 * //     APP_DB__PORT: '5432',
 * //     APP_DEBUG: 'true',
 * //     APP_FEATURE__X_ENABLED: 'false',
 * //     APP_WORKER__EMAILS__maxRunsPerMin: '100'
 * //     APP_WORKER__EMAILS__networkTimeoutMs: '100'
 * // }
 * const config = makeNestedConfig(process.env, {
 *     filter: (key) => key.startsWith('APP_'),
 *     stripPrefix: 'APP_',  // Strip the APP_ prefix
 *     forceAllCapToLower: true,
 *     separator: '__'
 * });
 *
 * console.log(config());
 * // {
 * //     db: {
 * //         host: 'localhost',
 * //         port: 5432
 * //     },
 * //     debug: true,
 * //     feature: {
 * //         x_enabled: false
 * //     },
 * //     worker: {
 * //         emails: {
 * //             maxRunsPerMin: 100,
 * //             networkTimeoutMs: 100
 * //         }
 * //     }
 * // }
 *
 * @example
 *
 * // Not forcing all-caps to lowercase
 * // Assuming process.env contains:
 * // {
 * //     APP_DB_HOST: 'localhost',
 * //     APP_DB_PORT: '5432',
 * //     APP_DEBUG: 'true',
 * //     APP_FEATURE_X_ENABLED: 'false'
 * //     APP_WORKER_EMAILS_maxRunsPerMin: '100'
 * //     APP_WORKER_EMAILS_networkTimeoutMs: '100'
 * // }
 *
 * const config = makeNestedConfig(process.env, {
 *     filter: (key) => key.startsWith('APP_'),
 *     stripPrefix: 'APP_',  // Strip the APP_ prefix
 *     forceAllCapToLower: false,
 *     separator: '_'
 * });
 *
 * console.log(config());
 * // {
 * //     DB: {
 * //         HOST: 'localhost',
 * //         PORT: 5432
 * //     },
 * //     DEBUG: true,
 * //     FEATURE: {
 * //         X_ENABLED: false
 * //     },
 * //     WORKER: {
 * //         EMAILS: {
 * //             maxRunsPerMin: 100,
 * //             networkTimeoutMs: 100
 * //         }
 * //     }
 * // }
 *
 * @example
 * // Using parseUnits to convert time and byte values
 * // Assuming process.env contains:
 * // {
 * //     APP_SESSION_TIMEOUT: '15m',
 * //     APP_CACHE_TTL: '1hour',
 * //     APP_MAX_UPLOAD_SIZE: '10mb',
 * //     APP_DISK_QUOTA: '100gb'
 * // }
 *
 * const config = makeNestedConfig(process.env, {
 *     filter: (key) => key.startsWith('APP_'),
 *     stripPrefix: 'APP_',
 *     parseUnits: true  // Enable unit parsing
 * });
 *
 * console.log(config());
 * // {
 * //     session: {
 * //         timeout: 900000  // 15 minutes in milliseconds
 * //     },
 * //     cache: {
 * //         ttl: 3600000  // 1 hour in milliseconds
 * //     },
 * //     max: {
 * //         upload: {
 * //             size: 10485760  // 10 megabytes in bytes
 * //         }
 * //     },
 * //     disk: {
 * //         quota: 107374182400  // 100 gigabytes in bytes
 * //     }
 * // }
 *
 * @example
 * // Using skipConversion to keep certain values as strings
 * // Assuming process.env contains:
 * // {
 * //     APP_API_KEY: '12345',
 * //     APP_SECRET_TOKEN: '67890',
 * //     APP_PORT: '3000',
 * //     APP_DEBUG: 'true'
 * // }
 *
 * const config = makeNestedConfig(process.env, {
 *     filter: (key) => key.startsWith('APP_'),
 *     stripPrefix: 'APP_',
 *     skipConversion: (key) => key.toLowerCase().includes('key') || key.toLowerCase().includes('token')
 * });
 *
 * console.log(config());
 * // {
 * //     api: {
 * //         key: '12345'  // Kept as string
 * //     },
 * //     secret: {
 * //         token: '67890'  // Kept as string
 * //     },
 * //     port: 3000,  // Converted to number
 * //     debug: true  // Converted to boolean
 * // }
 *
 */
export declare const makeNestedConfig: <C extends object = Record<string, any>, F = Record<string, string>>(_flatConfig: F, opts?: MakeNestedConfigOpts) => {
    allConfigs: () => C;
    getConfig: <P extends PathLeaves<C>, D extends PathValue<C, P>>(path: P, defaultValue?: D) => PathValue<C, P>;
};