package com.grash.utils;

import java.net.NetworkInterface;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.util.Collections;

public class FingerprintGenerator {

    public static String generateFingerprint() {
        try {
            StringBuilder sb = new StringBuilder();

            // Use MAC addresses of all interfaces as the base for the fingerprint
            for (NetworkInterface ni : Collections.list(NetworkInterface.getNetworkInterfaces())) {
                byte[] mac = ni.getHardwareAddress();
                if (mac != null) {
                    for (byte b : mac) {
                        sb.append(String.format("%02X", b));
                    }
                }
            }

            // Hash the collected MACs
            MessageDigest digest = MessageDigest.getInstance("SHA-256");
            byte[] hash = digest.digest(sb.toString().getBytes(StandardCharsets.UTF_8));

            // Convert to hex string
            StringBuilder hexString = new StringBuilder();
            for (byte b : hash) {
                hexString.append(String.format("%02x", b));
            }

            return hexString.toString();

        } catch (Exception e) {
            throw new RuntimeException("Failed to generate fingerprint", e);
        }
    }
}