validate-deso-identity-jwt.sc

import pdi.jwt.{Jwt, JwtAlgorithm}
import org.bitcoins.core.util.Base58
import org.bouncycastle.jce.spec.ECPublicKeySpec
import org.bouncycastle.jce.ECNamedCurveTable
import org.bouncycastle.jce.provider.BouncyCastleProvider
import java.security.{KeyFactory, PublicKey, Security}
import scala.util._

val jwtToken = "eyJhbGciOiJFUzI1NiIsInR5cCI6IkpXVCJ9.eyJpYXQiOjE2NDg1OTcwNzIsImV4cCI6MTY0ODU5NzY3Mn0.MFEtqJzrLTnjYwH4gAOsH-0qsrQIFsKcYHyHdE1WdWHLn_xa-fGPoV3OkDLr0Rk1IcIoawSrDXNxkyZR0wGhFw"
val desoPKey = "BC1YLhwpmWkgk2iM9yTSxzgUVhYjgessSPTiVHkkK9pMrhweqJnWrvK"

if (Security.getProvider("BC") == null)
  Security.addProvider(new BouncyCastleProvider())

val keyFactory: KeyFactory = KeyFactory.getInstance("EC", "BC")

val isSignatureValid: Boolean =
  Base58.decodeCheck(desoPKey) match {
    case Failure(_) => false
    case Success(desoPKeyBytes) =>
      val pointBytes = desoPKeyBytes.slice(3, desoPKeyBytes.length)
      if (pointBytes.length != 33) false
      else {
        val curveParams = ECNamedCurveTable.getParameterSpec("secp256k1")
        val pubKeySpec = new ECPublicKeySpec(curveParams.getCurve.decodePoint(pointBytes.toArray), curveParams)
        val publicKey: PublicKey = keyFactory.generatePublic(pubKeySpec)
        Jwt.isValid(jwtToken, publicKey, Seq(JwtAlgorithm.ES256))
      }
  }

if (Security.getProvider("BC") != null)
  Security.removeProvider("BC")