package io.spatio;

import java.nio.charset.StandardCharsets;

import java.security.*;

import java.util.Base64;

import static io.spatio.Utils.sanitizeHash;

public class SpatioSigner {

private final PrivateKey privateKey;

private final PublicKey publicKey;

public SpatioSigner() throws NoSuchAlgorithmException {

KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");

keyGen.initialize(2048);

KeyPair pair = keyGen.generateKeyPair();

this.privateKey = pair.getPrivate();

this.publicKey = pair.getPublic();

}

// public String sign(String hash) throws Exception {

// Signature signature = Signature.getInstance("SHA256withRSA");

// signature.initSign(privateKey);

// signature.update(hash.getBytes());

// byte[] digitalSignature = signature.sign();

// return Base64.getEncoder().encodeToString(digitalSignature);

// }

//

// public boolean verify(String hash, String signatureStr) throws Exception {

// Signature signature = Signature.getInstance("SHA256withRSA");

// signature.initVerify(publicKey);

// signature.update(hash.getBytes());

// byte[] digitalSignature = Base64.getDecoder().decode(signatureStr);

// return signature.verify(digitalSignature);

// }

public String sign(String hash) throws Exception {

String clean = sanitizeHash(hash);

Signature signature = Signature.getInstance("SHA256withRSA");

signature.initSign(privateKey);

signature.update(clean.getBytes(StandardCharsets.UTF_8)); // ✅ charset explicite

byte[] digitalSignature = signature.sign();

return Base64.getUrlEncoder() // ✅ URL-safe

.withoutPadding()

.encodeToString(digitalSignature);

}

public boolean verify(String hash, String signatureStr) throws Exception {

String clean = sanitizeHash(hash);

Signature signature = Signature.getInstance("SHA256withRSA");

signature.initVerify(publicKey);

signature.update(clean.getBytes(StandardCharsets.UTF_8)); // ✅ EXACTEMENT pareil

byte[] digitalSignature =

Base64.getUrlDecoder().decode(signatureStr);

return signature.verify(digitalSignature);

}

public PublicKey getPublicKey() {

return publicKey;

}

}