import { type PathNames, type PathValue } from '@logosdx/utils';
import type { FetchEngineCore } from '../engine/types.ts';
import type { OptionsEventData } from '../engine/events.ts';
import type { EngineConfig, InstanceHeaders, InstanceParams, InstanceState } from './types.ts';
/**
 * Manages configuration options for FetchEngine with deep path access.
 *
 * Provides a clean API for getting and setting nested configuration
 * values with type-safe paths and automatic event emission on mutations.
 * ConfigStore is the single source of truth for ALL configuration.
 *
 * The store is fully typed with EngineConfig, ensuring:
 * - `get('baseUrl')` returns `string`
 * - `get('retry.maxAttempts')` returns `number`
 * - `get('dedupePolicy')` returns the correct policy type
 * - `set('timeout', value)` validates value is a number
 *
 * @template H - Headers type
 * @template P - Params type
 * @template S - State type
 *
 * @example
 * ```typescript
 * // Access via engine.config
 * engine.config.get('baseUrl')        // string
 * engine.config.get('retry.maxAttempts')  // number
 *
 * // Set options (runtime configurable)
 * engine.config.set('baseUrl', 'https://new-api.com')
 * engine.config.set('retry.maxAttempts', 5)
 *
 * // Merge partial options
 * engine.config.set({ retry: { maxAttempts: 5 } })
 * ```
 */
export declare class ConfigStore<H = InstanceHeaders, P = InstanceParams, S = InstanceState> {
    constructor(engine: FetchEngineCore<H, P, S>, initialConfig: EngineConfig<H, P, S>);
    /**
     * Get a deep clone of all options or a specific nested value.
     *
     * Returns a cloned copy to prevent external mutations.
     * All return types are properly inferred from EngineConfig.
     *
     * @example
     * ```typescript
     * // Get all options
     * const opts = engine.config.get();  // EngineConfig<H, P, S>
     *
     * // Get nested value
     * const maxAttempts = engine.config.get('retry.maxAttempts');  // number
     * const baseUrl = engine.config.get('baseUrl');  // string
     * ```
     */
    get(): EngineConfig<H, P, S>;
    get<K extends PathNames<EngineConfig<H, P, S>> & string>(path: K): PathValue<EngineConfig<H, P, S>, K>;
    /**
     * Set options by path-value or by partial object merge.
     *
     * Runs registered pre-set validators against the pending change before
     * anything mutates — a validator that throws rejects the whole `set()`
     * call, so a rejected change never partially applies. Emits
     * 'config-change' after a successful update. All values are
     * type-checked against EngineConfig.
     *
     * @example
     * ```typescript
     * // Set by path (type-checked)
     * engine.config.set('baseUrl', 'https://new-api.com');  // OK
     * engine.config.set('retry.maxAttempts', 5);  // OK
     * engine.config.set('retry.maxAttempts', 'five');  // Type error!
     *
     * // Merge partial options
     * engine.config.set({ retry: { maxAttempts: 5 } });
     * ```
     */
    set<K extends PathNames<EngineConfig<H, P, S>> & string>(path: K, value: PathValue<EngineConfig<H, P, S>, K>): void;
    set<K extends PathNames<EngineConfig<H, P, S>> & string>(path: K, value: undefined): void;
    set(partial: Partial<EngineConfig<H, P, S>>): void;
    /**
     * Register a validator that runs against a pending `set()` before it
     * mutates the store.
     *
     * The validator throws to reject the change — nothing mutates and no
     * `config-change` event fires. Generic on purpose: the store has no
     * opinion on what makes a change valid, only that rejection must
     * happen before mutation. Callers (e.g. the engine's policy-ownership
     * check) own the actual rule.
     *
     * @param validator - Called with the pending change before mutation
     * @returns Cleanup function to unregister the validator
     */
    onBeforeSet(validator: (data: OptionsEventData) => void): () => void;
    /**
     * Set an option directly without emitting events.
     *
     * Used internally for backward compatibility methods that
     * emit their own specific events.
     *
     * @internal
     */
    _setDirect<K extends PathNames<EngineConfig<H, P, S>> & string>(path: K, value: PathValue<EngineConfig<H, P, S>, K>): void;
}
export type { EngineConfig, EngineType, RequestConfig, CallConfig, EngineRequestConfig, EngineLifecycle, ValidateConfig, DetermineTypeFn, InstanceHeaders, InstanceParams, InstanceState } from './types.ts';