import GRPCClient from "./GRPCClient";
import IClientConfiguration from "../../../interfaces/Client/IClientConfiguration";
import { KeyValueType } from "../../../types/KeyValue.type";
import { GetConfigurationResponse as GetConfigurationResponseResult } from "../../../types/configuration/GetConfigurationResponse";
import { SubscribeConfigurationCallback } from "../../../types/configuration/SubscribeConfigurationCallback";
import { SubscribeConfigurationStream } from "../../../types/configuration/SubscribeConfigurationStream";
/**
 * gRPC-based configuration building block implementation.
 *
 * Configuration allows reading and subscribing to configuration items from external stores.
 * This implementation uses gRPC for efficient streaming and subscription management.
 *
 * Supports configuration stores like Consul, Kubernetes ConfigMaps, AWS Parameter Store, etc.
 * Subscriptions enable reactive updates when configuration changes in the backing store.
 *
 * @implements {IClientConfiguration}
 * @see {@link https://docs.dapr.io/reference/api/configuration_api/} Dapr Configuration API
 * @see {@link DaprClient.configuration} for unified API
 *
 * @internal
 */
export default class GRPCClientConfiguration implements IClientConfiguration {
    /**
     * Reference to the underlying gRPC client.
     */
    client: GRPCClient;
    /**
     * Creates a gRPC configuration building block.
     *
     * @param client - The gRPC client instance
     */
    constructor(client: GRPCClient);
    /**
     * Retrieves configuration items from a configuration store.
     *
     * @param storeName - Name of the configuration store
     * @param keys - Configuration keys to retrieve (empty list = all keys)
     * @param metadataObj - Optional store-specific metadata
     *
     * @returns Promise resolving to retrieved configuration items
     *
     * @throws Rejects if store does not exist or retrieval fails
     *
     * @example
     * ```typescript
     * const config = await client.configuration.get("myconfig", ["db-host", "db-port"]);
     * console.log(config.items["db-host"]); // { key: "db-host", value: "localhost", version: "1" }
     * ```
     *
     * @see {@link https://docs.dapr.io/reference/api/configuration_api/#getting-configuration}
     */
    get(storeName: string, keys: string[], metadataObj?: KeyValueType): Promise<GetConfigurationResponseResult>;
    /**
     * Subscribes to all configuration items in a store.
     *
     * Invokes the callback immediately with current values, then again whenever values change.
     * Returns a subscription handle to stop listening.
     *
     * @param storeName - Name of the configuration store
     * @param cb - Callback invoked on subscription and configuration changes
     *
     * @returns Promise resolving to a subscription handle with stop() method
     *
     * @throws Rejects if store does not exist or subscription fails
     *
     * @example
     * ```typescript
     * const subscription = await client.configuration.subscribe("myconfig", (items) => {
     *   console.log("Configuration updated:", items);
     * });
     * // ... later ...
     * await subscription.stop();
     * ```
     *
     * @see {@link subscribeWithKeys}
     * @see {@link subscribeWithMetadata}
     */
    subscribe(storeName: string, cb: SubscribeConfigurationCallback): Promise<SubscribeConfigurationStream>;
    /**
     * Subscribes to specific configuration keys.
     *
     * @param storeName - Name of the configuration store
     * @param keys - Configuration keys to subscribe to
     * @param cb - Callback invoked on subscription and when keys change
     *
     * @returns Promise resolving to a subscription handle with stop() method
     *
     * @throws Rejects if store does not exist or subscription fails
     *
     * @example
     * ```typescript
     * const subscription = await client.configuration.subscribeWithKeys(
     *   "myconfig",
     *   ["db-host", "db-port"],
     *   (items) => console.log("DB config changed:", items)
     * );
     * ```
     *
     * @see {@link subscribe}
     * @see {@link subscribeWithMetadata}
     */
    subscribeWithKeys(storeName: string, keys: string[], cb: SubscribeConfigurationCallback): Promise<SubscribeConfigurationStream>;
    /**
     * Subscribes to configuration with store-specific metadata.
     *
     * @param storeName - Name of the configuration store
     * @param keys - Configuration keys to subscribe to
     * @param metadata - Store-specific metadata for the subscription
     * @param cb - Callback invoked on subscription and when keys change
     *
     * @returns Promise resolving to a subscription handle with stop() method
     *
     * @throws Rejects if store does not exist or subscription fails
     *
     * @see {@link subscribe}
     * @see {@link subscribeWithKeys}
     */
    subscribeWithMetadata(storeName: string, keys: string[], metadata: KeyValueType, cb: SubscribeConfigurationCallback): Promise<SubscribeConfigurationStream>;
    /**
     * Internal implementation for all subscribe methods.
     *
     * Establishes a gRPC streaming subscription with automatic cleanup.
     * Handles stream lifecycle (abort on stop) and unsubscribe messages.
     *
     * @private
     * @internal
     */
    _subscribe(storeName: string, cb: SubscribeConfigurationCallback, keys?: string[], metadataObj?: KeyValueType): Promise<SubscribeConfigurationStream>;
}