package com.its.utils;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.Base64;

public class SHA256Util {

    private static final String algorithm = "SHA-256";
    private static final String saltAlgorithm = "SHA1PRNG";

    public static String encrypt(String text) {
        StringBuffer sb = new StringBuffer();
        try {
            MessageDigest md = MessageDigest.getInstance(algorithm);
            md.update(text.getBytes());
            byte[] data = md.digest();
            for (byte b : data) {
                sb.append(String.format("%02x", b & 0xFF));
            }
        } catch (NoSuchAlgorithmException e) {
            return "";
        }
        return sb.toString();
    }

    public static String getSalt() {
        String salt;
        try {
            SecureRandom random = SecureRandom.getInstance(saltAlgorithm);
            byte[] bytes = new byte[16];
            random.nextBytes(bytes);
            salt = new String(Base64.getEncoder().encode(bytes));
        } catch (NoSuchAlgorithmException e) {
            return "1234567890";
        }
        return salt;
    }

    public static String encrypt(String text, String salt) {
        String saltText = text + salt;
        StringBuffer sb = new StringBuffer();
        try {
            MessageDigest md = MessageDigest.getInstance(algorithm);
            md.update(saltText.getBytes());
            byte[] data = md.digest();
            for (byte b : data) {
                sb.append(String.format("%02x", b & 0xFF));
            }
        } catch (NoSuchAlgorithmException e) {
            return "";
        }
        return sb.toString();
    }

}