Lothal-HTTP/LastModified.cpp at main · ShantanuGV/Lothal-HTTP · GitHub

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#include "LastModified.h"
#include "Logger.h"

#include <filesystem>
#include <chrono>
#include <ctime>
#include <iomanip>
#include <sstream>

using namespace std;

string LastModified::generate(
    const string& file)
{
    namespace fs = std::filesystem;

    if(!fs::exists(file))
        return "";

    auto ftime =
        fs::last_write_time(file);

    auto sctp =
        chrono::time_point_cast<
            chrono::system_clock::duration
        >(
            ftime -
            fs::file_time_type::clock::now()
            + chrono::system_clock::now()
        );

    time_t tt =
        chrono::system_clock::to_time_t(sctp);

    tm utc{};

#ifdef _WIN32
    gmtime_s(&utc, &tt);
#else
    gmtime_r(&tt, &utc);
#endif

    stringstream ss;

    ss
        << put_time(
            &utc,
            "%a, %d %b %Y %H:%M:%S GMT"
        );

    Logger::debug("LastModified generated for " + file + ": " + ss.str());

    return ss.str();
}