#include "serial_AT.hpp"

#include <algorithm>
#include <chrono>
#include <mutex>
#include <sstream>
#include <thread>

// ================== 全局 IMEI ==================
std::string IMEI;  // 一般 15 位

// ================== AT 任务结构 ==================
struct AtTask
{
    std::string cmd;
    int max_retries;
    int sent_count;
    std::chrono::steady_clock::time_point last_sent;
};

static std::unique_ptr<SerialPort> serial_at;
static std::thread serial_at_sender;
static std::mutex at_tasks_mutex;

// 只保留一个任务：AT+GSN
static std::vector<AtTask> at_tasks = {{"AT+GSN", 3, 0, {}}};

// ================== 发送线程 ==================
static void serial_at_send_loop()
{
    while (true)
    {
        if (!serial_at || !serial_at->is_open())
        {
            std::this_thread::sleep_for(std::chrono::seconds(1));
            continue;
        }

        auto now = std::chrono::steady_clock::now();
        std::lock_guard<std::mutex> lock(at_tasks_mutex);

        for (auto it = at_tasks.begin(); it != at_tasks.end();)
        {
            auto& task = *it;

            if (task.sent_count >= task.max_retries)
            {
                // 达到最大重试次数，直接移除
                it = at_tasks.erase(it);
                continue;
            }

            if (task.last_sent.time_since_epoch().count() == 0 ||
                std::chrono::duration_cast<std::chrono::seconds>(now - task.last_sent).count() >= 5)
            {
                serial_at->send_data(task.cmd + "\r\n");
                task.sent_count++;
                task.last_sent = now;
            }

            ++it;
        }

        std::this_thread::sleep_for(std::chrono::seconds(1));
    }
}

// ================== 接收处理 ==================
static void handle_serial_at_data(const std::string& data)
{
    std::istringstream iss(data);
    std::string line;

    while (std::getline(iss, line))
    {
        // trim
        line.erase(0, line.find_first_not_of(" \t\r\n"));
        line.erase(line.find_last_not_of(" \t\r\n") + 1);

        // IMEI：14~17 位纯数字（不同模组略有差异）
        if (line.size() >= 14 && line.size() <= 17 && std::all_of(line.begin(), line.end(), ::isdigit))
        {
            IMEI = line;
            LOG_INFO("[serial_at] IMEI = " + IMEI);

            // 成功后清空任务，不再发送 AT
            std::lock_guard<std::mutex> lock(at_tasks_mutex);
            at_tasks.clear();
            return;
        }
    }
}

// ================== 初始化接口 ==================
void init_serial_at(const std::string& device, int baudrate)
{
    serial_at = std::make_unique<SerialPort>("serial_at", device, baudrate, 5);

    serial_at->set_receive_callback(handle_serial_at_data);
    serial_at->start();

    serial_at_sender = std::thread(serial_at_send_loop);
    serial_at_sender.detach();
}