/*
 * =====================================================================================
 *
 *       Filename:  shm_queue.h
 *
 *    Description:  
 *
 *        Version:  1.0
 *        Created:  2021年03月25日 10时35分09秒
 *       Revision:  none
 *       Compiler:  gcc
 *
 *         Author:  Li Chao (), 
 *   Organization:  
 *
 * =====================================================================================
 */

#ifndef SHM_QUEUE_JE0OEUP3
#define SHM_QUEUE_JE0OEUP3

#include "robust.h"
#include "shm.h"
#include <atomic>
#include <boost/circular_buffer.hpp>
#include <chrono>

namespace bhome_shm
{

template <class D>
using Circular = boost::circular_buffer<D, Allocator<D>>;

template <class D>
class SharedQueue
{
public:
	SharedQueue(const uint32_t len, Allocator<D> const &alloc) :
	    queue_(len, alloc) {}

	bool Read(D &d, const int timeout_ms)
	{
		using namespace std::chrono;
		auto end_time = steady_clock::now() + milliseconds(timeout_ms);
		do {
			if (TryRead(d)) {
				return true;
			} else {
				robust::QuickSleep();
			}
		} while (steady_clock::now() < end_time);
		return false;
	}
	bool TryRead(D &d)
	{
		// bhome_shm::Guard lock(mutex_);
		if (!queue_.empty()) {
			d = queue_.front();
			queue_.pop_front();
			return true;
		} else {
			return false;
		}
	}
	bool TryWrite(const D &d)
	{
		// bhome_shm::Guard lock(mutex_);
		if (!queue_.full()) {
			queue_.push_back(d);
			return true;
		} else {
			return false;
		}
	}

private:
	Circular<D> queue_;
	// bhome_shm::Mutex mutex_;
};

template <int Power = 4>
class SharedQ63
{
public:
	template <class... T>
	explicit SharedQ63(T &&...t) {} // easy testing

	typedef int64_t Data;
	bool Read(Data &d, const int timeout_ms)
	{
		using namespace std::chrono;
		auto end_time = steady_clock::now() + milliseconds(timeout_ms);
		do {
			for (int i = 0; i < 100; ++i) {
				if (TryRead(d)) {
					return true;
				}
			}
			robust::QuickSleep();
		} while (steady_clock::now() < end_time);
		return false;
	}
	bool TryRead(Data &d, const bool try_more = true) { return queue_.pop(d, try_more); }
	bool TryWrite(const Data d, const bool try_more = true) { return queue_.push(d, try_more); }

private:
	robust::AtomicQueue<Power, Data> queue_;
};

} // namespace bhome_shm

#endif // end of include guard: SHM_QUEUE_JE0OEUP3