/**
 * Native sudo backend selection (priority order).
 *
 *   1. Electron  → `dialog.showMessageBox`
 *   2. macOS     → `osascript`
 *   3. Windows   → PowerShell
 *   4. Linux+GUI → `zenity` / `kdialog`
 *   5. headless  → editable TTY
 *   6. no channel → fail closed (deny) + log
 *
 * The environment probe is injectable so tests can force any branch without
 * touching the real platform / spawning `which`.
 */
import type { SudoBackend } from './types.js';
/** Probed runtime facts used to pick a backend. */
export interface SudoEnv {
    platform: NodeJS.Platform;
    isElectron: boolean;
    hasDisplay: boolean;
    hasTty: boolean;
    which: (cmd: string) => boolean;
}
/** Probe the live environment. */
export declare function detectSudoEnv(): SudoEnv;
/**
 * Select the highest-priority available backend for the given environment.
 * Always returns a backend — the deny backend is the fail-closed terminal.
 */
export declare function selectSudoBackend(env?: SudoEnv): SudoBackend;