/* UUID helpers.
 *
 * Author: Steffen Vogel <post@steffenvogel.de>
 * SPDX-FileCopyrightText: 2014-2023 Institute for Automation of Complex Power Systems, RWTH Aachen University
 * SPDX-License-Identifier: Apache-2.0
 */

#include <openssl/evp.h>

#include <villas/uuid.hpp>

using namespace villas::uuid;

std::string villas::uuid::toString(const uuid_t in) {
  uuid_string_t str;
  uuid_unparse_lower(in, str);
  return str;
}

int villas::uuid::generateFromString(uuid_t out, const std::string &data,
                                     const std::string &ns) {
  int ret;
  EVP_MD_CTX *c = EVP_MD_CTX_new();

  ret = EVP_DigestInit(c, EVP_md5());
  if (!ret)
    return -1;

  // Namespace
  ret = EVP_DigestUpdate(c, (unsigned char *)ns.c_str(), ns.size());
  if (!ret)
    return -1;

  // Data
  ret = EVP_DigestUpdate(c, (unsigned char *)data.c_str(), data.size());
  if (!ret)
    return -1;

  ret = EVP_DigestFinal(c, (unsigned char *)out, nullptr);
  if (!ret)
    return -1;

  EVP_MD_CTX_free(c);

  return 0;
}

int villas::uuid::generateFromString(uuid_t out, const std::string &data,
                                     const uuid_t ns) {
  int ret;
  EVP_MD_CTX *c = EVP_MD_CTX_new();

  ret = EVP_DigestInit(c, EVP_md5());
  if (!ret)
    return -1;

  // Namespace
  ret = EVP_DigestUpdate(c, (unsigned char *)ns, 16);
  if (!ret)
    return -1;

  // Data
  ret = EVP_DigestUpdate(c, (unsigned char *)data.c_str(), data.size());
  if (!ret)
    return -1;

  ret = EVP_DigestFinal(c, (unsigned char *)out, nullptr);
  if (!ret)
    return -1;

  EVP_MD_CTX_free(c);

  return 0;
}

int villas::uuid::generateFromJson(uuid_t out, json_t *json, const uuid_t ns) {
  char *str = json_dumps(json, JSON_COMPACT | JSON_SORT_KEYS);

  int ret = generateFromString(out, str, ns);

  free(str);

  return ret;
}