#pragma once

#include <algorithm>
#include <cstdlib>
#include <curl/curl.h>
#include <memory>
#include <optional>
#include <string>
#include <string_view>
#include <vector>

#include <memory_resource>

#include "span.hpp"
#include "utils.hpp"

/// TODO rename file to rublon/Core.hpp
/// TODO Create rublon utils

namespace rublon {
static size_t WriteMemoryCallback(void * contents, size_t size, size_t nmemb, void * userp) {
    size_t realsize   = size * nmemb;
    reinterpret_cast< std::string * >(userp)->append(static_cast< const char * >(contents), realsize);
    return realsize;
}

struct Request{
    std::map<std::string, std::string> headers;
    std::string body;
};

struct Response{
    std::map<std::string, std::string> headers;
    std::string body;
};


class CURL {
    std::unique_ptr< ::CURL, void (*)(::CURL *) > curl;

  public:
    CURL() : curl{std::unique_ptr< ::CURL, void (*)(::CURL *) >(curl_easy_init(), curl_easy_cleanup)} {}

    std::optional< Response > request(std::string_view uri, const Request &request) const {
        std::string response_data;
        response_data.reserve(1000);
        
            
        Response response;

        /// TODO this can be done on stack using pmr
        auto curl_headers = std::unique_ptr< curl_slist, void (*)(curl_slist *) >(nullptr, curl_slist_free_all);
        std::for_each(request.headers.begin(), request.headers.end(), [&](auto header) {
            curl_headers.reset(curl_slist_append(curl_headers.release(),(header.first + ": " + header.second).c_str()));
        });

        curl_easy_setopt(curl.get(), CURLOPT_VERBOSE, 1);
        curl_easy_setopt(curl.get(), CURLOPT_URL, uri.data());
        curl_easy_setopt(curl.get(), CURLOPT_HTTPHEADER, curl_headers.get());
        curl_easy_setopt(curl.get(), CURLOPT_POST, 1);
        curl_easy_setopt(curl.get(), CURLOPT_POSTFIELDS, request.body.data());
        curl_easy_setopt(curl.get(), CURLOPT_POSTFIELDSIZE, static_cast< u_int32_t >(request.body.size()));
        curl_easy_setopt(curl.get(), CURLOPT_HEADER, 1);
        curl_easy_setopt(curl.get(), CURLOPT_WRITEFUNCTION, WriteMemoryCallback);
        curl_easy_setopt(curl.get(), CURLOPT_WRITEDATA, &response_data);

        auto res = curl_easy_perform(curl.get());
        if(res != CURLE_OK) {
            //                debugLog("No response from Rublon server (perform)", "");
            return std::nullopt;
        }
        
        long size;
        curl_easy_getinfo(curl.get(), CURLINFO_HEADER_SIZE, &size);
        
        ///TODO ogarnąć alokację pamięci
        response.headers = details::headers({response_data.data(), static_cast<std::size_t>(size)});
        response.body = response_data.substr(size);

        return response;
    }
};

} // namespace rublon