wlan-cloud-owprov/src/framework/MicroServiceExtra.h

//
// Created by stephane bourque on 2022-10-26.
//

#pragma once

#include <map>
#include <string>

#include "Poco/BasicEvent.h"
#include "Poco/ExpireLRUCache.h"

namespace OpenWifi {
	class ConfigurationEntry {
	  public:
		template <typename T> explicit ConfigurationEntry(T def) : Default_(def), Current_(def) {}

		template <typename T>
		explicit ConfigurationEntry(T def, T cur, const std::string &Hint = "")
			: Default_(def), Current_(cur), Hint_(Hint) {}

		inline ConfigurationEntry() = default;
		inline ~ConfigurationEntry() = default;

		template <typename T> explicit operator T() const { return std::get<T>(Current_); }
		inline ConfigurationEntry &operator=(const char *v) {
			Current_ = std::string(v);
			return *this;
		}
		template <typename T> ConfigurationEntry &operator=(T v) {
			Current_ = (T)v;
			return *this;
		}

		void reset() { Current_ = Default_; }

	  private:
		std::variant<bool, uint64_t, std::string> Default_, Current_;
		std::string Hint_;
	};
	inline std::string to_string(const ConfigurationEntry &v) { return (std::string)v; }

	typedef std::map<std::string, ConfigurationEntry> ConfigurationMap_t;

	template <typename T> class FIFO {
	  public:
		explicit FIFO(uint32_t Size) : Size_(Size) { Buffer_ = new T[Size_]; }

		~FIFO() { delete[] Buffer_; }

		mutable Poco::BasicEvent<bool> Writable_;
		mutable Poco::BasicEvent<bool> Readable_;

		inline bool Read(T &t) {
			{
				std::lock_guard M(Mutex_);
				if (Write_ == Read_) {
					return false;
				}

				t = Buffer_[Read_++];
				if (Read_ == Size_) {
					Read_ = 0;
				}
				Used_--;
			}
			bool flag = true;
			Writable_.notify(this, flag);
			return true;
		}

		inline bool Write(const T &t) {
			{
				std::lock_guard M(Mutex_);

				Buffer_[Write_++] = t;
				if (Write_ == Size_) {
					Write_ = 0;
				}
				Used_++;
				MaxEverUsed_ = std::max(Used_, MaxEverUsed_);
			}
			bool flag = true;
			Readable_.notify(this, flag);
			return false;
		}

		inline bool isFull() {
			std::lock_guard M(Mutex_);
			return Used_ == Buffer_->capacity();
		}

		inline auto MaxEverUser() const { return MaxEverUsed_; }

	  private:
		std::recursive_mutex Mutex_;
		uint32_t Size_ = 0;
		uint32_t Read_ = 0;
		uint32_t Write_ = 0;
		uint32_t Used_ = 0;
		uint32_t MaxEverUsed_ = 0;
		T *Buffer_ = nullptr;
	};

	template <class Record, typename KeyType = std::string, int Size = 256, int Expiry = 60000>
	class RecordCache {
	  public:
		explicit RecordCache(KeyType Record::*Q) : MemberOffset(Q){};
		inline auto update(const Record &R) { return Cache_.update(R.*MemberOffset, R); }
		inline auto get(const KeyType &K) { return Cache_.get(K); }
		inline auto remove(const KeyType &K) { return Cache_.remove(K); }
		inline auto remove(const Record &R) { return Cache_.remove(R.*MemberOffset); }

	  private:
		KeyType Record::*MemberOffset;
		Poco::ExpireLRUCache<KeyType, Record> Cache_{Size, Expiry};
	};
} // namespace OpenWifi