/**
 * HashStrategy - Interface for hash algorithm implementations
 * This allows for different hashing strategies to be used interchangeably
 */
export interface HashStrategy {
    /**
     * Calculate a hash for the input data
     *
     * @param data - The data to hash (Buffer or string)
     * @returns The computed hash as a Buffer
     */
    hash(data: Buffer | string): Buffer;
    /**
     * Get the name of the hashing algorithm
     *
     * @returns The algorithm name as a string
     */
    getAlgorithmName(): string;
}
/**
 * SHA-256 hash strategy implementation
 */
export declare class SHA256Strategy implements HashStrategy {
    readonly name = "sha256";
    hash(data: Buffer | string): Buffer;
    getAlgorithmName(): string;
}
/**
 * SHA-512 hash strategy implementation
 */
export declare class SHA512Strategy implements HashStrategy {
    readonly name = "sha512";
    hash(data: Buffer | string): Buffer;
    getAlgorithmName(): string;
}
/**
 * Keccak-256 hash strategy implementation (used in Ethereum)
 */
export declare class Keccak256Strategy implements HashStrategy {
    readonly name = "keccak256";
    hash(data: Buffer | string): Buffer;
    getAlgorithmName(): string;
}
/**
 * Factory to create hash strategy instances
 */
export declare class HashStrategyFactory {
    static createStrategy(algorithm: 'sha256' | 'sha512' | 'keccak256'): HashStrategy;
}