import * as crypto from 'crypto';

export interface KeyPair {
  privateKey: string;
  publicKey: string;
}

export function generateKeyPair(): KeyPair {
  const { privateKey, publicKey } = crypto.generateKeyPairSync('rsa', {
    modulusLength: 2048,
    publicKeyEncoding: {
      type: 'spki',
      format: 'pem'
    },
    privateKeyEncoding: {
      type: 'pkcs8',
      format: 'pem'
    }
  });

  return { privateKey, publicKey };
}

export function signData(data: string, privateKey: string): string {
  const sign = crypto.createSign('SHA256');
  sign.update(data);
  sign.end();
  return sign.sign(privateKey, 'base64');
}

export function verifySignature(data: string, signature: string, publicKey: string): boolean {
  const verify = crypto.createVerify('SHA256');
  verify.update(data);
  verify.end();
  return verify.verify(publicKey, signature, 'base64');
}