// Copyright (c) 2017 GitHub, Inc.
// Use of this source code is governed by the MIT license that can be
// found in the LICENSE file.

#include "atom/browser/ui/certificate_trust.h"

#include <wincrypt.h>
#include <windows.h>

#include "base/callback.h"
#include "net/cert/cert_database.h"

namespace certificate_trust {

// Add the provided certificate to the Trusted Root Certificate Authorities
// store for the current user.
//
// This requires prompting the user to confirm they trust the certificate.
BOOL AddToTrustedRootStore(const PCCERT_CONTEXT cert_context,
                           const scoped_refptr<net::X509Certificate>& cert) {
  auto root_cert_store = CertOpenStore(
      CERT_STORE_PROV_SYSTEM,
      0,
      NULL,
      CERT_SYSTEM_STORE_CURRENT_USER,
      L"Root");

  if (root_cert_store == NULL) {
    return false;
  }

  auto result = CertAddCertificateContextToStore(
    root_cert_store,
    cert_context,
    CERT_STORE_ADD_REPLACE_EXISTING,
    NULL);

  if (result) {
    // force Chromium to reload it's database for this certificate
    auto cert_db = net::CertDatabase::GetInstance();
    cert_db->NotifyObserversCertDBChanged();
  }

  CertCloseStore(root_cert_store, CERT_CLOSE_STORE_FORCE_FLAG);

  return result;
}

CERT_CHAIN_PARA GetCertificateChainParameters() {
  CERT_ENHKEY_USAGE enhkey_usage;
  enhkey_usage.cUsageIdentifier = 0;
  enhkey_usage.rgpszUsageIdentifier = NULL;

  CERT_USAGE_MATCH cert_usage;
  // ensure the rules are applied to the entire chain
  cert_usage.dwType = USAGE_MATCH_TYPE_AND;
  cert_usage.Usage = enhkey_usage;

  CERT_CHAIN_PARA params = { sizeof(CERT_CHAIN_PARA) };
  params.RequestedUsage = cert_usage;

  return params;
}

void ShowCertificateTrust(atom::NativeWindow* parent_window,
                          const scoped_refptr<net::X509Certificate>& cert,
                          const std::string& message,
                          const ShowTrustCallback& callback) {
  PCCERT_CHAIN_CONTEXT chain_context;

  auto cert_context = cert->CreateOSCertChainForCert();

  auto params = GetCertificateChainParameters();

  if (CertGetCertificateChain(NULL,
                              cert_context,
                              NULL,
                              NULL,
                              &params,
                              NULL,
                              NULL,
                              &chain_context)) {
    auto error_status = chain_context->TrustStatus.dwErrorStatus;
    if (error_status == CERT_TRUST_IS_SELF_SIGNED ||
        error_status == CERT_TRUST_IS_UNTRUSTED_ROOT) {
      // these are the only scenarios we're interested in supporting
      AddToTrustedRootStore(cert_context, cert);
    }

    CertFreeCertificateChain(chain_context);
  }

  CertFreeCertificateContext(cert_context);

  callback.Run();
}

}  // namespace certificate_trust