#pragma once
/**
 * @file RuleStatShm.h
 * @brief 共享内存 map，用于 mon↔cron 进程间冷数据交换
 *
 * 热数据（display）改走本地缓存 → Memcached，不经过共享内存。
 * 冷数据（stat_values/running_time/shear_times 等）保留在共享内存中，
 * 使用 ShmSpinLock（kill(pid,0) 崩溃接管）+ std::mutex（进程内）双层锁。
 *
 * @author your name (you@domain.com)
 * @version 0.2
 * @date 2023-10-18
 *
 * Copyright: Baosight Co. Ltd.
 * DO NOT COPY/USE WITHOUT PERMISSION
 */
#include <boost/interprocess/sync/interprocess_mutex.hpp>
#include <boost/interprocess/sync/scoped_lock.hpp>
#include <atomic>
#include <cerrno>
#include <csignal>
#include <ctime>
#include <mutex>
#include <unistd.h>
#include "shm_header.h"

namespace RuleStatShm {

using namespace ShmHeader;

/// 跨进程自旋锁——崩溃安全（kill(pid,0) 检测持有者存活，ESRCH 则接管）
struct ShmSpinLock {
  std::atomic<pid_t> owner{0};

  ShmSpinLock() = default;
  ShmSpinLock(const ShmSpinLock &) = delete;
  ShmSpinLock &operator=(const ShmSpinLock &) = delete;

  void lock() {
    pid_t my_pid = ::getpid();
    while (true) {
      pid_t expected = 0;
      if (owner.compare_exchange_strong(expected, my_pid,
                                         std::memory_order_acquire)) {
        return;
      }
      // 持有者进程已死 → 接管
      if (::kill(expected, 0) != 0 && errno == ESRCH) {
        if (owner.compare_exchange_strong(expected, my_pid,
                                           std::memory_order_acquire)) {
          return;
        }
        continue;
      }
      // 持有者存活，短暂退避
      struct timespec ts = {0, 100000}; // 100us
      ::nanosleep(&ts, nullptr);
    }
  }

  void unlock() {
    pid_t my_pid = ::getpid();
    pid_t expected = my_pid;
    owner.compare_exchange_strong(expected, 0, std::memory_order_release);
  }
};

/// 双层锁：进程内 std::mutex + 跨进程 ShmSpinLock
struct DualLock {
  std::mutex local;
  ShmSpinLock &shm;

  DualLock(ShmSpinLock &s) : shm(s) {}

  void lock() {
    local.lock();
    shm.lock();
  }
  void unlock() {
    shm.unlock();
    local.unlock();
  }
};

namespace {

const static std::string dir_path = "/users/dsc/shm";
const static std::string shm_file = "MapRuleStat"; ///<映射文件名
const double data_size = 1024;                     ///< 数据大小 MB
const size_t stat_size_min = 1000;  ///<统计样本最小批处理量
const size_t stat_size_max = 10000; ///<统计样本最大储存量

static managed_mapped_file_t
    obj_mapped_file(bipc::open_or_create,
                    (dir_path + "/" + shm_file + "_boost.mmap").c_str(),
                    mix_cc::data_size::MB(data_size));

static void_allocator
    default_allocator(obj_mapped_file.get_segment_manager()); ///<默认分配器
static vec_allocator_s
    items_allocator(obj_mapped_file.get_segment_manager()); ///< vector_s分配器

static ShmSpinLock *shm_lock =
    obj_mapped_file.find_or_construct<ShmSpinLock>("RuleStatLock")();

thread_local static char_string tl_key_object("", default_allocator);
thread_local static char_string tl_key_delete("", default_allocator);

char_string &get_thread_local_key(const std::string &key) {
  tl_key_object = key.c_str();
  return tl_key_object;
}

char_string &get_thread_local_delete_key(const std::string &key) {
  tl_key_delete = key.c_str();
  return tl_key_delete;
}

} // namespace

/// 本地完整数据（AlgBase 使用，标准分配器）
struct RuleStatLocal {
  double alarm_value = 0;
  double current_value = 0;
  double limit_up = 0;
  double limit_down = 0;
  std::vector<std::string> items;
  std::vector<double> stat_values;
  bool fetch_mark = false;
  double running_time = 0;
  int64_t shear_times = 0;
  int64_t alarm_times = 0;
  std::string last_alarm_time = "无报警";
  std::string dev_coder = "无";
  std::string unit;
};

/// 共享内存冷数据（mon↔cron 交换用）
struct RuleStatCold {
  vector_d stat_values;           ///<统计值，mon攒样本，cron消费
  bool fetch_mark = false;        ///<取数据标记
  double running_time = 0;        ///<累积的运行时间
  int64_t shear_times = 0;        ///<剪切次数
  int64_t alarm_times = 0;        ///<报警次数
  bipc::string last_alarm_time = "无报警"; ///<上次报警时间
  bipc::string dev_coder = "无";           ///<设备编码

  RuleStatCold()
      : stat_values(default_allocator) {}

  double limit_precision(double data, int precision = 2) const {
    double factor = std::pow(10, precision);
    return std::round(data * factor) / factor;
  }

  bool update_static(const RuleStatCold &value) {
    try {
      running_time = value.running_time;
      shear_times = value.shear_times;
      alarm_times = value.alarm_times;
      last_alarm_time = value.last_alarm_time;
      dev_coder = value.dev_coder;
    } catch (const std::exception &e) {
      return false;
    }
    return true;
  }

  bool update_cold(const RuleStatCold &value) {
    try {
      stat_values = value.stat_values;
      fetch_mark = value.fetch_mark;
      running_time = value.running_time;
      shear_times = value.shear_times;
    } catch (...) {
      return false;
    }
    return true;
  }
};

///< key 是string的情况
typedef std::pair<const char_string, RuleStatCold> pair_s;
typedef bipc::node_allocator<pair_s, mapped_segment_manager_t>
    allocator_s;
typedef std::less<char_string> less_s;
typedef bipc::map<char_string, RuleStatCold, less_s, allocator_s> MapRuleStat_s;
typedef MapRuleStat_s::iterator map_iter_s;

/// 共享内存 map 操作（仅冷数据）
struct MapRuleStat {
private:
  MapRuleStat_s *p_msg_map = obj_mapped_file.find_or_construct<MapRuleStat_s>(
      shm_file.c_str())(less_s(), obj_mapped_file.get_segment_manager());
  DualLock lock_{*shm_lock};

public:
  // ── mon 高频调用 ──

  bool add_stat_value(const std::string &key, const double &value) {
    try {
      std::lock_guard<DualLock> guard(lock_);
      if (p_msg_map->operator[](get_thread_local_key(key)).fetch_mark) {
        p_msg_map->operator[](get_thread_local_key(key)).stat_values.clear();
        p_msg_map->operator[](get_thread_local_key(key)).fetch_mark = false;
      }
      if (p_msg_map->operator[](get_thread_local_key(key)).stat_values.size() <
          stat_size_max) {
        p_msg_map->operator[](get_thread_local_key(key))
            .stat_values.push_back(value);
      }
      return true;
    } catch (const std::exception &e) {
      return false;
    }
  }

  /// mon 写入累积的冷字段（stat_values, running_time, shear_times）
  bool update_cold_fields(const std::string &key, const RuleStatCold &value) {
    std::lock_guard<DualLock> guard(lock_);
    try {
      if (p_msg_map->find(get_thread_local_key(key)) != p_msg_map->end()) {
        p_msg_map->operator[](get_thread_local_key(key)).update_cold(value);
      } else {
        p_msg_map->operator[](get_thread_local_key(key)) = value;
      }
      return true;
    } catch (const std::exception &e) {
      return false;
    }
  }

  /// cron 写入静态字段（running_time, alarm_times, last_alarm_time, dev_coder 等）
  bool update_static_fields(const std::string &key, const RuleStatCold &value) {
    std::lock_guard<DualLock> guard(lock_);
    try {
      if (p_msg_map->find(get_thread_local_key(key)) != p_msg_map->end()) {
        p_msg_map->operator[](get_thread_local_key(key)).update_static(value);
        return true;
      }
      p_msg_map->operator[](get_thread_local_key(key)) = value;
      return true;
    } catch (const std::exception &e) {
      return false;
    }
  }

  // ── cron 调用 ──

  bool get_stat_value(const std::string &key, RuleStatCold &value) {
    try {
      std::lock_guard<DualLock> guard(lock_);
      if (!p_msg_map->operator[](get_thread_local_key(key)).fetch_mark &&
          p_msg_map->operator[](get_thread_local_key(key)).stat_values.size() >
              stat_size_min) {
        value.stat_values =
            p_msg_map->operator[](get_thread_local_key(key)).stat_values;
        p_msg_map->operator[](get_thread_local_key(key)).fetch_mark = true;
        return true;
      }
      return false;
    } catch (const std::exception &e) {
      return false;
    }
  }

  // ── 管理操作 ──

  bool delete_data(const std::string &key) {
    std::lock_guard<DualLock> guard(lock_);
    try {
      if (p_msg_map->find(get_thread_local_delete_key(key)) !=
          p_msg_map->end()) {
        p_msg_map->erase(get_thread_local_delete_key(key));
      }
      return true;
    } catch (const std::exception &e) {
      return false;
    }
  }

  size_t size() {
    std::lock_guard<DualLock> guard(lock_);
    return p_msg_map->size();
  }

  bool empty() {
    std::lock_guard<DualLock> guard(lock_);
    return p_msg_map->empty();
  }

  std::vector<std::string>
  find_rule_id(const std::vector<std::string> &ruleid) {
    std::lock_guard<DualLock> guard(lock_);
    std::vector<std::string> res;
    if (p_msg_map->empty()) {
      return {};
    }
    for (auto iter1 = p_msg_map->begin(); iter1 != p_msg_map->end(); iter1++) {
      auto resV = std::find(ruleid.begin(), ruleid.end(), iter1->first);
      if (resV != ruleid.end()) {
        res.push_back(iter1->first);
      }
    }
    return res;
  }

  std::vector<std::string>
  find_no_rule_id(const std::vector<std::string> &ruleid) {
    std::lock_guard<DualLock> guard(lock_);
    std::vector<std::string> res;
    if (p_msg_map->empty()) {
      return {};
    }
    for (auto iter1 = p_msg_map->begin(); iter1 != p_msg_map->end(); iter1++) {
      auto resV = std::find(ruleid.begin(), ruleid.end(), iter1->first);
      if (resV == ruleid.end()) {
        res.push_back(iter1->first);
      }
    }
    return res;
  }
};

} // namespace RuleStatShm