import { type MessageKey } from './locales/en.js';
export type Locale = 'en' | 'zh';
/** Coerce an arbitrary string (env/config/user input) to a supported Locale, defaulting to 'en'. */
export declare function normalizeLocale(raw: string | undefined | null): Locale;
/**
 * Best-effort detection of the operator's system language from POSIX locale env vars.
 * Precedence follows POSIX: LC_ALL > LC_MESSAGES > LANG > LANGUAGE. A value whose language
 * tag starts with "zh" (zh_CN, zh_TW, zh-Hans, ...) maps to 'zh'; everything else (incl. unset,
 * "C", "POSIX") falls back to 'en'. Used by `cortex init` to pre-select the language option.
 */
export declare function detectSystemLocale(env?: NodeJS.ProcessEnv): Locale;
export declare function setLocale(loc: Locale): void;
export declare function getLocale(): Locale;
/**
 * Translate a message key in the active locale. Resolution order:
 *   active-locale table → en table (fallback) → the raw key (last resort).
 * `${param}` placeholders are substituted from `params`.
 */
export declare function t(key: MessageKey | string, params?: Record<string, string | number>): string;