/**
 * Settings service interface
 * Provides centralized settings management with validation, persistence, and reactive updates
 */
import type { Settings, DeepPartial, ValidationResult, SettingsListener, Unsubscribe } from './types';
export interface ISettingsService {
    /**
     * Initialize the service (load from storage, run migrations)
     * Must be called before other methods
     */
    init(): Promise<void>;
    /**
     * Get current settings (immutable)
     */
    getSettings(): Settings;
    /**
     * Update settings (deep merge, validates, persists, emits event)
     * Returns updated settings on success
     * Throws SettingsValidationError if validation fails
     */
    updateSettings(partial: DeepPartial<Settings>): Promise<Settings>;
    /**
     * Reset to default settings
     */
    resetToDefaults(): Promise<Settings>;
    /**
     * Load a preset (e.g., 'acs')
     */
    loadPreset(name: string): Promise<Settings>;
    /**
     * Get available preset names
     */
    getAvailablePresets(): string[];
    /**
     * Validate settings without applying
     */
    validateSettings(settings: Partial<Settings>): ValidationResult;
    /**
     * Export settings as JSON string
     */
    exportSettings(): string;
    /**
     * Import settings from JSON string
     * Validates and applies the imported settings
     */
    importSettings(json: string): Promise<Settings>;
    /**
     * Subscribe to settings changes
     * Returns unsubscribe function
     */
    subscribe(listener: SettingsListener): Unsubscribe;
}