// @flow
import nacl from 'tweetnacl';
import bs58 from 'bs58';
import type {KeyPair} from 'tweetnacl';

/**
 * Base 58 encoded public key
 *
 * @typedef {string} PublicKey
 */
export type PublicKey = string;

/**
 * Represents an account key pair (public and secret keys).
 */
export class Account {
  _keypair: KeyPair;

  /**
   * Create a new Account object
   *
   * If the secretKey parameter is not provided a new key pair is randomly
   * created for the account
   *
   * @param secretKey Secret key for the account
   */
  constructor(secretKey: ?Buffer = null) {
    if (secretKey) {
      this._keypair = nacl.sign.keyPair.fromSecretKey(secretKey);
    } else {
      this._keypair = nacl.sign.keyPair();
    }
  }

  /**
   * The public key for this account
   */
  get publicKey(): PublicKey {
    return bs58.encode(this._keypair.publicKey);
  }

  /**
   * The **unencrypted** secret key for this account
   */
  get secretKey(): Buffer {
    return this._keypair.secretKey;
  }
}