#include "CurlFtp.h"
#include <iostream>
#include <regex>
#include <iosfwd>

CurlFtp::CurlFtp()
{

}


CurlFtp::~CurlFtp()
{


}

/* 检查文件夹是否存在，不确定好不好用 */
// bool CurlFtp::isDirExists(const std::string &ftpUrl, const std::string &username, const std::string &password)
// {
//     CURL *curl;
//     CURLcode res;
//     bool result = false;
//     std::string retList;

//     curl_global_init(CURL_GLOBAL_DEFAULT);
//     curl = curl_easy_init();
//     if(curl) 
//     {
//         curl_easy_setopt(curl, CURLOPT_URL, ftpUrl.c_str());
//         curl_easy_setopt(curl, CURLOPT_USERNAME, username.c_str());
//         curl_easy_setopt(curl, CURLOPT_PASSWORD, password.c_str());
//         // curl_easy_setopt(curl, CURLOPT_DIRLISTONLY, 1L); // We only want the directory listing

        
//         curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, writeCallback);
//         curl_easy_setopt(curl, CURLOPT_WRITEDATA, &retList);

//         res = curl_easy_perform(curl);
//         // printf("res = %d\n", res);
//         if(res != CURLE_OK) 
//         {
//             fprintf(stderr, "getDirList() failed, error code %d, :%s\n",res, curl_easy_strerror(res));
//         }
//         else 
//         {
//             // std::cout << "Directory list: \n" << retList << std::endl;
//         }
//         curl_easy_cleanup(curl);
//     }
    
//     curl_global_cleanup();
    
//     return result;
// }

/* 使用正则表达式提取出文件夹 */
// bool CurlFtp::extractDirectories(const std::string& responseString)
// {
//     std::regex directoryRegex(R"(^d.*\s(\S+)$)");
//     std::smatch match;

//     std::istringstream retStream(responseString);
//     std::string line;

//     while (std::getline(retStream, line)) 
//     {
//         if (std::regex_match(line, match, directoryRegex)) 
//         {
//             std::cout << "Directory: " << match[1] << std::endl;
//         }
//     }
//     return true;
// }

/**
 * @brief 列出FTP文件夹
 * 
 * @param ftpUrl 需要列出文件夹的FTP地址
 * @param username 
 * @param password 
 * @return std::string 
 */
std::string CurlFtp::listDir(const std::string &ftpUrl, const std::string &username, const std::string &password)
{
    CURL *curl;
    CURLcode res;
    bool result = false;
    std::string retList;

    curl_global_init(CURL_GLOBAL_DEFAULT);
    curl = curl_easy_init();
    if(curl) 
    {
        curl_easy_setopt(curl, CURLOPT_URL, ftpUrl.c_str());
        curl_easy_setopt(curl, CURLOPT_USERNAME, username.c_str());
        curl_easy_setopt(curl, CURLOPT_PASSWORD, password.c_str());
        // curl_easy_setopt(curl, CURLOPT_DIRLISTONLY, 1L); // We only want the directory listing

        
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, writeCallback);
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &retList);

        res = curl_easy_perform(curl);
        // printf("res = %d\n", res);
        if(res != CURLE_OK) 
        {
            fprintf(stderr, "getDirList() failed, error code %d, :%s\n",res, curl_easy_strerror(res));
        }
        else 
        {
            // std::cout << "Directory list: \n" << retList << std::endl;
        }
        curl_easy_cleanup(curl);
    }
    
    curl_global_cleanup();
    return retList;
}

/* 写入回调函数，listDir需要调用 */
size_t CurlFtp::writeCallback(void *contents, size_t size, size_t nmemb, std::string *s) 
{
    size_t newLength = size*nmemb;
    size_t oldLength = s->size();
    try
    {
        s->resize(oldLength + newLength);
    }
    catch(std::bad_alloc &e)
    {
        //handle memory problem
        return 0;
    }

    std::copy((char*)contents,(char*)contents+newLength,s->begin()+oldLength);
    return size*nmemb;
}

// Callback function to collect the list of files
static int filelistCallback(void* buffer, size_t size, size_t nmemb, void* userp)
{
    std::vector<std::string>* fileList = static_cast<std::vector<std::string>*>(userp);
    std::string line(static_cast<char*>(buffer), size * nmemb);
    fileList->push_back(line);
    return size * nmemb;
}

/* 列出文件夹中的所有文件 */
bool CurlFtp::listFiles(const std::string &ftpUrl, const std::string &username, const std::string &password, std::vector<std::string>& fileList)
{
    CURL *curl;
    CURLcode res;
    bool result = false;

    curl_global_init(CURL_GLOBAL_DEFAULT);
    curl = curl_easy_init();
    if(curl)
    {
        curl_easy_setopt(curl, CURLOPT_URL, (ftpUrl).c_str());
        curl_easy_setopt(curl, CURLOPT_USERNAME, username.c_str());
        curl_easy_setopt(curl, CURLOPT_PASSWORD, password.c_str());
        curl_easy_setopt(curl, CURLOPT_DIRLISTONLY, 1L);
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, filelistCallback);
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &fileList);

        res = curl_easy_perform(curl);
        if(res != CURLE_OK) 
        {
            fprintf(stderr, "Failed to get file list, error code :%d ,%s\n", res, curl_easy_strerror(res));
        }
        else
        {
            // for(const std::string& filename : fileList)
            // {
            //     printf("%s\n", filename.c_str());
            // }
            result = true;
        }

        curl_easy_cleanup(curl);
    }

    curl_global_cleanup();
    return result;
}



/* 创建文件夹 */
bool CurlFtp::createDir(const std::string &ftpUrl, const std::string &username, const std::string &password, const std::string &dirName)
{
    CURL *curl;
    CURLcode res;
    bool result = false;

    curl_global_init(CURL_GLOBAL_DEFAULT);
    curl = curl_easy_init();
    if(curl)
    {
        curl_easy_setopt(curl, CURLOPT_URL, ftpUrl.c_str());
        curl_easy_setopt(curl, CURLOPT_USERNAME, username.c_str());
        curl_easy_setopt(curl, CURLOPT_PASSWORD, password.c_str());

        // Create a list of FTP commands to be executed on the server
        struct curl_slist *headerlist = NULL;
        std::string mkdir = "MKD " + dirName;
        headerlist = curl_slist_append(headerlist, mkdir.c_str());

        // Set the list of FTP commands to be executed on the server before the transfer
        curl_easy_setopt(curl, CURLOPT_QUOTE, headerlist);
        // Tell libcurl to not include the body in the output
        curl_easy_setopt(curl, CURLOPT_NOBODY, 1L);

        res = curl_easy_perform(curl);

        if(res != CURLE_OK) 
        {
            fprintf(stderr, "createDir() failed, error code :%d ,%s\n", res, curl_easy_strerror(res));
            result = false;
        }else
        {
            result = true;
        }

        curl_easy_cleanup(curl);
        curl_slist_free_all(headerlist);
    }

    curl_global_cleanup();
    return result;
}