/**
 * Key Unit - Public-facing cryptographic key unit
 * [🔑] Clean unit that holds public key material and can learn signing capabilities
 *
 * Design principles:
 * - Key is the public-facing unit (holds public key only)
 * - Can learn signing capabilities from Signer units via teach/learn pattern
 * - Simple getters for public properties (no complex methods)
 * - Full Unit architecture with execute, learn, teach, capabilities
 *
 * @author Synet Team
 */
import { Unit, type TeachingContract, type UnitProps } from '@synet/unit';
import type { KeyType } from './keys';
/**
 * Configuration for creating a Key unit
 */
export interface KeyConfig {
    publicKeyPEM: string;
    keyType: KeyType;
    meta?: Record<string, unknown>;
}
/**
 * Props interface for Key unit - follows Unit Architecture Doctrine
 */
export interface KeyProps extends UnitProps {
    publicKeyPEM: string;
    keyType: KeyType;
    keyId: string;
    meta: Record<string, unknown>;
}
export declare class Key extends Unit<KeyProps> {
    protected constructor(props: KeyProps);
    get publicKeyPEM(): string;
    get keyType(): KeyType;
    get keyId(): string;
    get meta(): Record<string, unknown>;
    /**
     * Create Key unit from config
     */
    static create(config: KeyConfig): Key;
    private static isValidPublicKey;
    whoami(): string;
    capabilities(): string[];
    help(): void;
    teach(): TeachingContract;
    /**
     * Verify signature using public key
     * Must learn verification capability from Signer to use this method
     */
    verify(data: string, signature: string): Promise<boolean>;
    /**
     * Sign data - uses learned signing capability if available
     */
    sign(data: string): Promise<string>;
    /**
     * Check if this key can sign
     * Returns true if signing capabilities have been learned
     */
    canSign(): boolean;
    /**
     * Get public key (compatibility method)
     */
    getPublicKey(): string;
    toJSON(): Record<string, unknown>;
    /**
     * Override learn method to handle Signer teachings
     */
    learn(teachings: TeachingContract[]): Promise<boolean>;
}