#include <iostream>
#include <curl/curl.h>

// libcurl库下载链接：https://curl.haxx.se/download.html
// jsoncpp库下载链接：https://github.com/open-source-parsers/jsoncpp/

const static std::string request_url = "https://aip.baidubce.com/rest/2.0/ocr/v1/two_factors_verification";
static std::string twoFactorsVerification_result;

/**
 * curl发送http请求调用的回调函数，回调函数中对返回的json格式的body进行了解析，解析结果储存在全局的静态变量当中
 * @param 参数定义见libcurl文档
 * @return 返回值定义见libcurl文档
 */
static size_t callback(void *ptr, size_t size, size_t nmemb, void *stream) {
  // 获取到的body存放在ptr中，先将其转换为string格式
  twoFactorsVerification_result = std::string((char *) ptr, size * nmemb);
  return size * nmemb;
}

/**
 * OCR-企业二要素核验
 * @return 调用成功返回0，发生错误返回其他错误码
 */
int twoFactorsVerification(std::string &json_result, const std::string &access_token) {
  std::string url = request_url + "?access_token=" + access_token;
  CURL *curl = NULL;
  CURLcode result_code;
  int is_success;
  curl = curl_easy_init();
  if (curl) {
    curl_easy_setopt(curl, CURLOPT_URL, url.data());
    curl_easy_setopt(curl, CURLOPT_POST, 1);
    curl_httppost *post = NULL;
    curl_httppost *last = NULL;
    curl_formadd(&post, &last, CURLFORM_COPYNAME, "company", CURLFORM_COPYCONTENTS, "企业名称", CURLFORM_END);
    curl_formadd(&post, &last, CURLFORM_COPYNAME, "regnum", CURLFORM_COPYCONTENTS, "社会统一信用代码", CURLFORM_END);
    curl_easy_setopt(curl, CURLOPT_HTTPPOST, post);
    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, callback);
    result_code = curl_easy_perform(curl);
    if (result_code != CURLE_OK) {
      fprintf(stderr, "curl_easy_perform() failed: %s",curl_easy_strerror(result_code));
      is_success = 1;
      return is_success;
    }
    json_result = twoFactorsVerification_result;
    curl_easy_cleanup(curl);
    is_success = 0;
  } else {
    fprintf(stderr, "curl_easy_init() failed.");
    is_success = 1;
  }
  return is_success;
}