#include "network/tcp_server.h"
#include "mqtt/mqtt_client.h"
#include "mqtt/mqtt_router.h"
#include "systemMonitor/system_monitor.h"
#include "spdlog/spdlog.h"
#include "modbus/modbus_master_poller.h"
#include <boost/asio.hpp>
#include <boost/asio/steady_timer.hpp> 
#include <csignal>
#include <iostream>
#include <functional> 

// 用于 ASIO 服务的全局 io_context
boost::asio::io_context g_io_context;

/**
 * @brief 处理终止信号 (SIGINT, SIGTERM).
 *
 * 这个函数会优雅地停止 Boost.Asio 的 io_context，
 * 这将导致 main() 函数中的 io_context.run() 调用解除阻塞，
 * 从而允许程序干净地退出。
 *
 * @param signum 接收到的信号编号。
 */
void signalHandler(int signum) {
    spdlog::warn("Interrupt signal ({}) received. Shutting down.", signum);
    // 向 io_context 提交一个停止事件。这是一种线程安全的方式
    // 来告诉 io_context 停止其事件循环。
    g_io_context.stop();
}

void poll_system_metrics(
    boost::asio::steady_timer& timer,
    SystemMonitor::SystemMonitor& monitor,
    MqttClient& mqtt_client
) {
    // a. 采集数据
    auto cpu_util = monitor.getCpuUtilization(); 
    auto mem_info = monitor.getMemoryInfo();
    double mem_total_gb = mem_info.total_kb / 1024.0 / 1024.0;
    
    // b. (示例) 将数据通过 MQTT 发送出去
    std::string topic = "proxy/system_status";
    std::string payload = "{\"cpu_usage\":" + std::to_string(cpu_util.totalUsagePercentage) + 
                          ",\"mem_total_gb\":" + std::to_string(mem_total_gb) + "}";
    mqtt_client.publish(topic, payload);
    spdlog::debug("System metrics published.");

    // c. 将定时器重置到 15 秒后
    timer.expires_at(timer.expiry() + std::chrono::seconds(15));

    // d. 异步等待定时器，到期后再次调用本函数，形成循环
    timer.async_wait(std::bind(poll_system_metrics, std::ref(timer), std::ref(monitor), std::ref(mqtt_client)));
}

int main(int argc, char* argv[]) {

    try {
        spdlog::set_level(spdlog::level::debug); // 设置日志级别为 debug，方便调试
        spdlog::info("Edge Proxy starting up...");
    } catch (const spdlog::spdlog_ex& ex) {
        std::cerr << "Log initialization failed: " << ex.what() << std::endl;
        return 1;
    }

    // 注册信号处理器
    signal(SIGINT, signalHandler);
    signal(SIGTERM, signalHandler);

    try {
        constexpr uint16_t tcp_port = 8888;
        MqttClient mqtt_client("tcp://mqtt-broker:1883", "edge-proxy-main-client");
        MqttRouter mqtt_router(mqtt_client);
        std::vector<uint16_t> listen_ports = { 8888 };
        TCPServer tcp_server(g_io_context, listen_ports, mqtt_client);
        SystemMonitor::SystemMonitor monitor;

        mqtt_client.connect();
        mqtt_router.start();

        monitor.getCpuUtilization(); 
        boost::asio::steady_timer timer(g_io_context, std::chrono::seconds(15));
        timer.async_wait(std::bind(poll_system_metrics, std::ref(timer), std::ref(monitor), std::ref(mqtt_client)));

        auto report_to_mqtt = [&](const UnifiedData& data) {
            std::string topic = "devices/" + data.device_id + "/data";
            mqtt_client.publish(topic, data.data_json, 1, false);
        };

        // 配置并启动Modbus轮询器
        ModbusDeviceConfig temp_sensor_config = {
            .device_id = "temp_sensor_workshop1",
            .ip_address = "192.168.1.120", // 您的Modbus设备的IP地址
            .port = 502,                   // Modbus TCP标准端口
            .slave_id = 1,                 // 设备的从站ID
            .start_address = 0,            // 要读取的第一个寄存器的地址
            .quantity = 8,                 // 从起始地址开始，总共读取多少个寄存器
            .poll_interval_ms = 2000       // 每2000毫秒轮询一次
        };
        // =========================================================================
        
        // 创建轮询器实例 (使用std::make_shared确保生命周期)
        auto poller = std::make_shared<ModbusMasterPoller>(g_io_context, temp_sensor_config, report_to_mqtt);
        poller->start();

        spdlog::info("All services are running. Press Ctrl+C to exit.");

        g_io_context.run();

        spdlog::info("Shutting down MQTT client...");
        mqtt_client.disconnect();

    } catch (const std::exception& e) {
        spdlog::critical("An unhandled exception occurred: {}", e.what());
        return 1;
    }

    spdlog::info("Server has been shut down gracefully. Exiting.");
    return 0;
}