#pragma comment ( lib, "ws2_32.lib" )
#pragma comment ( lib, "winmm.lib" )
#pragma comment ( lib, "wldap32.lib" )
#pragma comment(lib, "Advapi32.lib")

#ifdef _DEBUG
#pragma comment(lib,"libcurld.lib")
#else
#pragma comment(lib,"libcurl.lib")
#endif

#include "../curl/curl.h"

int HttpPost(string host, string send, string & resp)
{
    CURL *curl;
    CURLcode res;
    char tmp_str[256] = { 0 };
    std::stringstream out;

    //HTTP报文头  
    struct curl_slist* headers = NULL;

    char url[50] = { 0 };
    strcpy(url, host.c_str());
    //AfxMessageBox(_T("开始"));
    curl = curl_easy_init();

    if (curl)
    {
        //构建json
        string jsonout = send;
        char sendchar[4096] = { 0 };
        char ret[4096] = { 0 };
        strcpy(sendchar, jsonout.c_str());
        GBKtoU8(sendchar, ret);//如果发送报文内没有中文字符则可以不转换
        jsonout = ret;
       
        //设置url
        curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "POST");
        curl_easy_setopt(curl, CURLOPT_URL, url);

        //设置http发送的内容类型为JSON
        //构建HTTP报文头  
        AfxMessageBox(StrToCstr(jsonout));

        headers = curl_slist_append(headers, "cache-control:no-cache");
        headers = curl_slist_append(headers, "Content-Type:application/json");
       
        curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headers);

                                                // 设置要POST的JSON数据
        curl_easy_setopt(curl, CURLOPT_POSTFIELDS, jsonout.c_str());
        curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE, jsonout.size());//设置上传json串长度,这个设置可以忽略

                                                                      // 设置接收数据的处理函数和存放变量
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);//设置回调函数
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &out);//设置写数据
        res = curl_easy_perform(curl);//执行

        curl_slist_free_all(headers); /* free the list again */

         resp = out.str();//返回请求值
        char reta[4096] = { 0 };
        UtfToGbk(resp.c_str(), reta);
        resp = reta;
        AfxMessageBox(StrToCstr(resp));

        /* always cleanup */
        curl_easy_cleanup(curl);
    }
    return 0;
}

void UtfToGbk(const char* utf8, char * gbk)
{
    int len = MultiByteToWideChar(CP_UTF8, 0, utf8, -1, NULL, 0);
    wchar_t* wstr = new wchar_t[len + 1];
    memset(wstr, 0, len + 1);
    MultiByteToWideChar(CP_UTF8, 0, utf8, -1, wstr, len);
    len = WideCharToMultiByte(CP_ACP, 0, wstr, -1, NULL, 0, NULL, NULL);
    //char* str = new char[len+1];
    memset(gbk, 0, len + 1);
    //WideCharToMultiByte(CP_ACP, 0, wstr, -1, str, len, NULL, NULL);
    WideCharToMultiByte(CP_ACP, 0, wstr, -1, gbk, len, NULL, NULL);
    if (wstr) delete[] wstr;

    //return str;
}

void GBKtoU8(char gbkstr[], char *utf8str)
{
    int len_wchart;
    wchar_t *unicode;
    int len_utf8;

    len_wchart = MultiByteToWideChar(CP_ACP, 0, gbkstr, -1, NULL, 0);   //得到GBK=>UTF8后需要字符串长度
    unicode = (wchar_t *)malloc(len_wchart * sizeof(wchar_t)); //分配空间存储UNICODE中间结果
    MultiByteToWideChar(CP_ACP, 0, gbkstr, -1, unicode, len_wchart);        //GBK => UINCODE
    len_utf8 = WideCharToMultiByte(CP_UTF8, 0, unicode, -1, NULL, 0, NULL, NULL);  //UINCODE=>UTF8需要的长度
    WideCharToMultiByte(CP_UTF8, 0, unicode, -1, utf8str, len_utf8, NULL, NULL);   //UNICODE => UTF8

    free(unicode);
}