package com.paymentlink.util;

import java.security.SecureRandom;
import java.util.UUID;

public class IdGenerator {

    private static final SecureRandom RANDOM = new SecureRandom();
    private static final String ALPHA_NUMERIC = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";

    /**
     * Generate order ID in format: ORD-{timestamp}-{random}
     */
    public static String generateOrderId() {
        long timestamp = System.currentTimeMillis();
        String randomPart = generateRandomString(6);
        return String.format("ORD-%d-%s", timestamp, randomPart);
    }

    /**
     * Generate payment link ID (hex format, 32 characters)
     */
    public static String generatePaymentLinkId() {
        return UUID.randomUUID().toString().replace("-", "");
    }

    /**
     * Generate random alphanumeric string
     */
    private static String generateRandomString(int length) {
        StringBuilder sb = new StringBuilder(length);
        for (int i = 0; i < length; i++) {
            sb.append(ALPHA_NUMERIC.charAt(RANDOM.nextInt(ALPHA_NUMERIC.length())));
        }
        return sb.toString();
    }
}