import { DEFAULT_PREFERENCES, PREFERENCES_SCHEMA_VERSION, type ProjectPreferences } from './preferences-types.js';
export { DEFAULT_PREFERENCES, PREFERENCES_SCHEMA_VERSION };
export type { ProjectPreferences } from './preferences-types.js';
export declare function preferencesPath(projectRoot: string): string;
export declare function loadPreferences(projectRoot: string): ProjectPreferences;
export declare function savePreferences(projectRoot: string, overrides: Partial<ProjectPreferences>): ProjectPreferences;
/**
 * Atomic write helper for preferences.json. Writes to `<path>.tmp-<pid>-<ts>`
 * and renames over the target. On Windows, `rename` is atomic for files
 * on the same volume; on POSIX, `rename(2)` is atomic by spec.
 */
export declare function writeAtomic(filePath: string, prefs: ProjectPreferences): void;
/**
 * (any `schema_version` older than PREFERENCES_SCHEMA_VERSION) to the
 * current shape. Returns the migrated object + a list of changes
 * applied (for surfacing in the CLI envelope and the migration log).
 *
 * v1's `agentShieldPrompt` and `loopAutonomousEnabled` were already
 * present, so they carry through unchanged. The `fanout` field is new
 * in v2 — it defaults to `{ defaultMode: 'fan-out' }` so the pre-v2
 * behavior (peak-code SKILL instructed fan-out when ≥ 2 leaves) is
 * preserved.
 */
export type MigrateResult = {
    readonly fromVersion: string;
    readonly toVersion: typeof PREFERENCES_SCHEMA_VERSION;
    readonly migrated: ProjectPreferences;
    readonly changes: readonly string[];
    readonly written: boolean;
};
export declare function migratePreferences(projectRoot: string, opts?: {
    write?: boolean;
    now?: () => Date;
}): MigrateResult | null;