#pragma once

#include <limits.h>
#include <unistd.h>

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

namespace common
{

// 获取当前北京时间字符串 (精确到毫秒)
inline std::string get_current_time_string()
{
    using namespace std::chrono;
    auto now = system_clock::now();
    auto ms = duration_cast<milliseconds>(now.time_since_epoch()) % 1000;

    // 先转 UTC
    auto t = system_clock::to_time_t(now);
    std::tm utc_tm = *std::gmtime(&t);

    utc_tm.tm_hour += 8;
    mktime(&utc_tm);

    std::ostringstream oss;
    oss << std::put_time(&utc_tm, "%Y-%m-%d %H:%M:%S") << '.' << std::setw(3) << std::setfill('0') << ms.count();
    return oss.str();
}

// 获取当前日期字符串 (仅日期，用于日志文件名)
inline std::string get_current_date_string()
{
    using namespace std::chrono;
    auto now = system_clock::now();
    auto t = system_clock::to_time_t(now);

    // 转成 UTC
    std::tm utc_tm = *std::gmtime(&t);

    // UTC + 8 小时
    utc_tm.tm_hour += 8;
    mktime(&utc_tm);  // 自动修正日期

    std::ostringstream oss;
    oss << std::put_time(&utc_tm, "%Y-%m-%d");
    return oss.str();
}

// 获取文件大小
inline size_t get_file_size(const std::string& filename)
{
    std::ifstream in(filename, std::ifstream::ate | std::ifstream::binary);
    return in.is_open() ? static_cast<size_t>(in.tellg()) : 0;
}

// 获取可执行文件目录下的文件完整路径
inline std::string get_executable_file_path(const std::string& filename)
{
    char result[PATH_MAX];
    ssize_t count = readlink("/proc/self/exe", result, PATH_MAX);
    std::string path(result, count);
    auto dir = path.substr(0, path.find_last_of('/'));
    if (dir.back() != '/') dir += '/';
    return dir + filename;
}

// 获取当前毫秒时间戳（steady_clock，不受系统时间影响）
inline uint64_t get_timestamp_ms()
{
    using namespace std::chrono;
    return duration_cast<milliseconds>(steady_clock::now().time_since_epoch()).count();
}

}  // namespace common