#include "SystemUsage.h"
#include "BoostLog.h"
#include "DateTime.h"
#include "NetworkUtility.h"
#include "ServiceManager.h"
#include <boost/algorithm/string/classification.hpp>
#include <boost/algorithm/string/split.hpp>
#include <boost/algorithm/string/trim.hpp>
#include <boost/json/object.hpp>
#include <boost/json/serialize.hpp>
#include <fstream>
#include <sstream>
#include <sys/statvfs.h>
#include <sys/sysinfo.h>

SystemUsage::SystemUsage(boost::asio::io_context &ioContext, const std::string &accessToken)
    : m_ioContext(ioContext), m_accessToken(accessToken) {
    m_timer = std::make_shared<boost::asio::system_timer>(m_ioContext);
    // LOG(info) << "access token: " << m_accessToken;
}

void SystemUsage::start() {
    using namespace std::chrono;
    m_timer->expires_after(seconds(10));
    m_timer->async_wait([this](const boost::system::error_code &error) {
        if (error) {
            LOG(error) << error.message();
            return;
        }
        auto currentCpuStats = readCpuData();
        int usage = 100.0f * cpuUsage(m_lastCpuStats, currentCpuStats);
        publish("yuyun_cpu_usage", usage, "%", "CPU占用率");

        publish("yuyun_disk_usage", static_cast<int>(100.0f * diskUsage("/")), "%", "磁盘占用率");
        m_lastCpuStats = currentCpuStats;

        m_networkStats.push_back(networkStats("ens18"));
        while (m_networkStats.size() >= 2) {
            constexpr auto SpeedInterval = seconds(60 * 15);
            auto front = m_networkStats.front();
            auto back = m_networkStats.back();
            auto duration = duration_cast<seconds>(back.time - front.time);
            if (duration > SpeedInterval) {
                m_networkStats.pop_front();
            } else {
                constexpr auto gigabyte = 1024 * 1024 * 1024;
                auto receiveGigabyte = static_cast<float>(back.receiveBytes - front.receiveBytes) / gigabyte;
                auto transmitGigabyte = static_cast<float>(back.transmitBytes - front.transmitBytes) / gigabyte;
                auto speed = (receiveGigabyte + transmitGigabyte) / duration.count() * SpeedInterval.count();
                LOG(info) << "network speed: " << std::fixed << std::setprecision(2) << speed << "GB/h";
                static system_clock::time_point lastNotify;
                auto now = system_clock::now();
                if ((speed >= 1.f) && (duration_cast<minutes>(now - lastNotify) > minutes(10))) { // 一个小时1GB的流量
                    std::ostringstream oss;
                    oss << "当前服务器流量存在异常, " << DateTime::toString(front.time) << " - "
                        << DateTime::toString(back.time) << ": " << std::endl;
                    oss << "进出总速率: " << std::fixed << std::setprecision(2) << speed << "GB/h" << std::endl;
                    oss << "接收流量: " << std::fixed << std::setprecision(2) << receiveGigabyte << "GB" << std::endl;
                    oss << "发送流量: " << std::fixed << std::setprecision(2) << transmitGigabyte << "GB" << std::endl;
                    auto manager = Amass::Singleton<ServiceManager>::instance();
                    if (manager) manager->sendMessage(NotifyServerChan, oss.str());
                    LOG(warning) << oss.str();
                    lastNotify = now;
                }
                break;
            }
        }
        start();
    });
}

void SystemUsage::publish(const std::string_view &deviceName, float value, const std::string_view &unit,
                          const std::string_view &friendlyName) {
    // LOG(info) << "cpu usage: " << usage << "%";
    Http::Client http(m_ioContext, Http::Transparent);
    std::ostringstream oss;
    oss << "Bearer " << m_accessToken;
    http.addRequestField(boost::beast::http::field::authorization, oss.str());
    http.addRequestField(boost::beast::http::field::content_type, "application/json");

    boost::json::object request;
    request["state"] = value;
    boost::json::object attributes;
    attributes["unit_of_measurement"] = unit;
    attributes["friendly_name"] = friendlyName;
    request["attributes"] = std::move(attributes);

    oss.str("");
    oss << "/api/states/sensor." << deviceName;
    boost::system::error_code error;
    auto reply = http.post("iot.amass.fun", "80", oss.str(), boost::json::serialize(request), error);
    if (error) {
        LOG(error) << error.message();
    }
}

SystemUsage::CpuStats SystemUsage::readCpuData() {
    CpuStats result;
    std::ifstream proc_stat("/proc/stat");
    if (proc_stat.good()) {
        std::string line;
        getline(proc_stat, line);

        unsigned int *stats_p = (unsigned int *)&result;
        std::stringstream iss(line);
        std::string cpu;
        iss >> cpu;
        while (iss >> *stats_p) {
            stats_p++;
        };
    }
    proc_stat.close();
    return result;
}

float SystemUsage::cpuUsage(const CpuStats &first, const CpuStats &second) {
    const float active_time = static_cast<float>(second.totalActive() - first.totalActive());
    const float idle_time = static_cast<float>(second.totalIdle() - first.totalIdle());
    const float total_time = active_time + idle_time;
    return active_time / total_time;
}

float SystemUsage::diskUsage(const std::string &disk) {
    struct statvfs diskData;
    statvfs(disk.c_str(), &diskData);

    auto total = diskData.f_blocks;
    auto free = diskData.f_bfree;
    auto diff = total - free;

    float result = static_cast<float>(diff) / total;

    return result;
}

SystemUsage::NetworkStats SystemUsage::networkStats(const std::string &interface) {
    NetworkStats ret;
    try {
        std::ifstream ifs("/proc/net/dev");
        if (!ifs.is_open()) {
            LOG(error) << "failed to open /proc/net/dev";
            return ret;
        }
        std::string line;
        while (std::getline(ifs, line)) {
            if (line.find(interface) == std::string::npos) continue;
            boost::trim(line);
            std::vector<std::string> results;
            boost::split(results, line, boost::algorithm::is_any_of(" "), boost::token_compress_on);
            if (results.size() < 9) continue;
            ret.interface = results.at(0);
            ret.interface = ret.interface.substr(0, ret.interface.size() - 1); // Remove the trailing ':'
            ret.receiveBytes = std::stoll(results.at(1));
            ret.transmitBytes = std::stoll(results.at(9));
            // LOG(info) << "interface: " << ret.interface << ", receive bytes: " << ret.receiveBytes
            //           << ", transmit bytes: " << ret.transmitBytes;
            break;
        }
    } catch (const std::exception &e) {
        LOG(error) << e.what();
    }
    return ret;
}