import { PortableRegistry } from '@dedot/codecs';
import { SignerPayloadJSON } from '@dedot/types';
import { ISubstrateClient } from '../../types.js';
import { SignedExtension } from './SignedExtension.js';
/**
 * A fallback signed extension that can be used for extensions
 * that don't require external input.
 *
 * This extension is automatically used for:
 * - Unknown extensions with empty struct or tuple types
 * - Known extensions that don't require input, such as:
 *   - CheckNonZeroSender: Ensures sender is not the zero address
 *   - CheckWeight: Block resource (weight) limit check
 *   - PrevalidateAttests: Validates `attest` calls prior to execution
 *   - StorageWeightReclaim: Storage weight reclaim mechanism
 *
 * These extensions have empty struct or tuple types and don't need explicit implementation.
 */
export declare class FallbackSignedExtension extends SignedExtension {
    private readonly extensionIdent;
    constructor(client: ISubstrateClient, options: any, extensionIdent: string);
    get identifier(): string;
    init(): Promise<void>;
    fromPayload(_: SignerPayloadJSON): Promise<void>;
    toPayload(): Partial<SignerPayloadJSON>;
}
/**
 * Checks if a type is an empty struct or tuple (doesn't require external input).
 *
 * @param registry The portable registry
 * @param typeId The type ID to check
 * @returns True if the type is an empty struct or tuple, false otherwise
 */
export declare function isEmptyStructOrTuple(registry: PortableRegistry, typeId: number): boolean;