////////////////////////////////////////////////////////////////////////////////
// Copyright 2019 Google LLC.
//
// This software is licensed under the terms defined in the Widevine Master
// License Agreement. For a copy of this agreement, please contact
// widevine-licensing@google.com.
////////////////////////////////////////////////////////////////////////////////
//
// Description:
//   Implementation of fake EC key generator. Returns precomputed test keys.

#include "common/fake_ec_key_source.h"

#include <memory>
#include <string>
#include <utility>

#include "glog/logging.h"
#include "common/ec_key.h"
#include "common/ec_test_keys.h"

namespace widevine {

FakeECKeySource::FakeECKeySource() {
  ECTestKeys ec_test_keys;
  CHECK(SetKey(ECPrivateKey::SECP256R1,
               ec_test_keys.private_test_key_1_secp256r1(),
               ec_test_keys.public_test_key_1_secp256r1()));

  CHECK(SetKey(ECPrivateKey::SECP384R1,
               ec_test_keys.private_test_key_1_secp384r1(),
               ec_test_keys.public_test_key_1_secp384r1()));

  CHECK(SetKey(ECPrivateKey::SECP521R1,
               ec_test_keys.private_test_key_1_secp521r1(),
               ec_test_keys.public_test_key_1_secp521r1()));
}

bool FakeECKeySource::SetKey(ECPrivateKey::EllipticCurve curve,
                             const std::string& private_key,
                             const std::string& public_key) {
  std::unique_ptr<ECPrivateKey> pri_key = ECPrivateKey::Create(private_key);
  std::unique_ptr<ECPublicKey> pub_key = ECPublicKey::Create(public_key);
  if (pub_key == nullptr || pri_key == nullptr) {
    LOG(ERROR) << "public key or private key was null.";
    return false;
  }
  if (!pri_key->MatchesPublicKey(*pub_key)) {
    LOG(ERROR) << "Public and private keys do not match.";
    return false;
  }
  if (pri_key->Curve() != curve) {
    LOG(ERROR) << "Curve does not match specified curve.";
    return false;
  }

  test_keys_[curve] = std::make_pair(private_key, public_key);

  return true;
}

bool FakeECKeySource::GetECKey(ECPrivateKey::EllipticCurve curve,
                               std::string* private_key,
                               std::string* public_key) {
  CHECK(private_key);
  CHECK(public_key);

  const auto keys = test_keys_.find(curve);
  if (keys == test_keys_.end()) {
    return false;
  }

  std::tie(*private_key, *public_key) = keys->second;

  return true;
}

}  // namespace widevine