#include "Utils/Snowflake.hpp"

namespace Chattr {

Snowflake GenerateID() {
    static struct EpochInitializer {
        EpochInitializer() {
            EPOCH = std::chrono::system_clock::now();
        }
        std::chrono::system_clock::time_point EPOCH;
    } epochInitializer;
    
    static std::mutex snowflakeGenerateMutex_;

    std::lock_guard<std::mutex> lock(snowflakeGenerateMutex_);

    std::size_t tid;
    #ifdef _WIN32
        tid = static_cast<std::size_t>(GetCurrentThreadId());
    #elif __linux__
        tid = static_cast<std::size_t>(pthread_self());
    #endif

    thread_local static int sequence = 0;
    Snowflake id = {};

    auto timestamp = std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock::now() - epochInitializer.EPOCH);
    id.timestamp = timestamp.count();
    id.instance = tid;
    id.sequence = sequence++;

    return id;
}

};