CPP_Core/Core/Statistics/Statistics.h

#pragma once
#include "../Base/global_include.h"
#include "global.h"

namespace Psc {
class Base_Statistics {
protected:
  size_t start_time;

  [[nodiscard]] static uint64_t get_current_ms() {
    using namespace std::chrono;
    return duration_cast<milliseconds>(steady_clock::now().time_since_epoch())
        .count();
  }

public:
  Base_Statistics() : start_time(get_current_ms()) {}
  virtual JSON to_json() const = 0;
  virtual ~Base_Statistics() = default;

  unsigned int get_start_time() const { return start_time; }
};

// Speed Statistics 类，继承自 Base_Statistics\
// 单位B/s

class Speed_Statistics : public Base_Statistics {
public:
  double cur_total{};
  double instant_speed{};
  double average_speed{};
  size_t times{};

  Speed_Statistics &operator+=(const Speed_Statistics &rhs) {
    this->cur_total += rhs.cur_total;
    this->instant_speed += rhs.instant_speed;
    this->average_speed += rhs.average_speed;
    this->times += rhs.times;
    return *this;
  }

  Speed_Statistics() { clear(); }

  void clear() {
    cur_total = 0;
    instant_speed = -1;
    average_speed = -1;
    times = 0;
  }

  [[nodiscard]] JSON to_json() const override {
    JSON ret = JSON::object();
    // Ret_J(cur_total)
    Ret_J(instant_speed) Ret_J(average_speed) Ret_J(times) return ret;
  }

  [[nodiscard]] std::string to_string() const {
    return VAR_STR_4(instant_speed, average_speed, cur_total, times);
  }

  void update(unsigned int len) {
    cur_total += static_cast<double>(len);
    auto true_period_ms = get_current_ms() - start_time;
    size_t period = 100; // 100 ms 统计一次
    times++;
    if (instant_speed == -1) {
      instant_speed = 0;
      start_time = get_current_ms();
    }

    if (true_period_ms > period) {

      // 字节/秒
      instant_speed = cur_total / true_period_ms * 1000;

      // 转换成 KB/s
      // instant_speed /= 1024.0f;

      // 平均速度
      double average_times = 10.0f;
      if (average_speed >= 0) {
        average_speed = average_speed * (average_times - 1.0f) / average_times +
                        instant_speed * (1.0f) / average_times;
      } else {
        average_speed = instant_speed;
      }

      start_time = get_current_ms();
      cur_total = 0;
    }
  }
};

// Value Statistics 类，继承自 Base_Statistics
class Value_Statistics : public Base_Statistics {
public:
  double max{};
  double min{};
  double average{};
  double instant{};
  size_t times = 0;
  [[nodiscard]] JSON to_json() const override {
    JSON ret = JSON::object();
    Ret_J(max) Ret_J(min) Ret_J(average) Ret_J(instant) return ret;
  }

  [[nodiscard]] std::string to_string() const {
    return VAR_STR_5(min, max, average, instant, times);
  }

  Value_Statistics() { clear(); }

  void clear() {
    max = std::numeric_limits<double>::min();
    min = std::numeric_limits<double>::max();
    average = -1;
    instant = 0;
    times = 0;
  }

  void update(double value) {
    max = std::max(max, value);
    min = std::min(min, value);
    double average_times = 10.0f; // 平均取近十次
    instant = value;
    if (average != -1) {
      average = average * (average_times - 1.0f) / average_times +
                instant * (1.0f) / average_times;
    } else {
      average = instant;
    }
    times++;
  }
};

// Probability Statistics 类，继承自 Base_Statistics
class Probability_Statistics : public Base_Statistics {
public:
  unsigned short instant{};
  unsigned short average{};
  unsigned int count{};     // 成功次数
  unsigned int total{};     // 总次数
  unsigned int total_max{}; // 总次数
  [[nodiscard]] JSON to_json() const override {
    JSON ret = JSON::object();
    Ret_J(instant) Ret_J(average) Ret_J(count) Ret_J(total)
        Ret_J(total_max) return ret;
  }
  Probability_Statistics() { clear(); }

  void clear() {
    instant = 0;
    average = 0;
    count = 0;
    total = 0;
    total_max = 10;
  }

  // 成功调用   update(1)
  // 失败调用  update(-1)
  //  可以调用  update(n)  n > 0 表示连续成功n次
  //  可以调用  update(n)  n < 0 表示连续失败n次
  void update(int count_change) {
    if (count_change == 0) {
      count_change = -1;
    }
    if (count_change > 0) {
      count += count_change;
      total += count_change;
    } else if (count_change < 0) {
      total += -count_change;
    }

    if (total < total_max)
      return; // 至少累计 100 次才统计一次

    // instant 概率 (0-1000)
    instant = (count * 1000) / total;

    if (average == 0) {
      average = instant;
    } else {
      // 平滑平均，base = 8
      average = ((average << 3) - average + instant) >> 3;
    }

    // 清零重新统计一批
    count = 0;
    total = 0;
  }
};

} // namespace Psc