package com.isp.bkashautomation.security

import java.security.MessageDigest
import javax.crypto.Mac
import javax.crypto.spec.SecretKeySpec

object SecurityHelper {
    /**
     * Computes HMAC-SHA256 signature to protect webhooks from tampering and spoofing
     */
    fun generateHmacSha256(data: String, secretKey: String): String {
        val mac = Mac.getInstance("HmacSHA256")
        val secretKeySpec = SecretKeySpec(secretKey.toByteArray(Charsets.UTF_8), "HmacSHA256")
        mac.init(secretKeySpec)
        val hmacBytes = mac.doFinal(data.toByteArray(Charsets.UTF_8))
        return hmacBytes.joinToString("") { "%02x".format(it) }
    }
}