/*
 * =====================================================================================
 *
 *       Filename:  shm_socket.h
 *
 *    Description:  
 *
 *        Version:  1.0
 *        Created:  2021年03月30日 15时49分19秒
 *       Revision:  none
 *       Compiler:  gcc
 *
 *         Author:  Li Chao (), 
 *   Organization:  
 *
 * =====================================================================================
 */

#ifndef SHM_SOCKET_GWTJHBPO
#define SHM_SOCKET_GWTJHBPO

#include "bh_util.h"
#include "defs.h"
#include "sendq.h"
#include "shm_msg_queue.h"
#include <atomic>
#include <boost/noncopyable.hpp>
#include <condition_variable>
#include <functional>
#include <memory>
#include <mutex>
#include <thread>
#include <vector>

using namespace bhome_msg;
class ShmSocket : private boost::noncopyable
{

protected:
	typedef ShmMsgQueue Queue;

public:
	typedef ShmMsgQueue::MQId MQId;
	typedef bhome_shm::SharedMemory Shm;
	typedef std::function<void(ShmSocket &sock, Queue::RawData &val)> RawRecvCB;
	typedef std::function<void(ShmSocket &sock, MsgI &imsg, BHMsgHead &head)> RecvCB;
	typedef std::function<bool(ShmSocket &sock, MsgI &imsg, BHMsgHead &head)> PartialRecvCB;
	typedef std::function<void(ShmSocket &sock)> IdleCB;

	ShmSocket(Shm &shm, const MQId id, Mode mode) :
	    run_(false), mq_(shm, id, mode), alloc_id_(0), send_buffer_(shm) { Start(); }
	ShmSocket(int64_t abs_addr, Shm &shm, const MQId id) :
	    run_(false), mq_(abs_addr, shm, id), alloc_id_(0), send_buffer_(shm) { Start(); }

	~ShmSocket();
	static bool Remove(SharedMemory &shm, const MQId id) { return Queue::Remove(shm, id); }
	bool Remove() { return Remove(shm(), id()); }
	MQId id() const { return mq().Id(); }
	int64_t AbsAddr() const { return mq().AbsAddr(); }
	void SetNodeProc(const int proc_index, const int socket_index)
	{
		node_proc_index_ = proc_index;
		socket_index_ = socket_index;
	}
	// start recv.
	bool Start(int nworker = 1, const RecvCB &onMsg = RecvCB(), const RawRecvCB &onRaw = RawRecvCB(), const IdleCB &onIdle = IdleCB());
	bool Start(const RecvCB &onData, const IdleCB &onIdle, int nworker = 1) { return Start(nworker, onData, RawRecvCB(), onIdle); }
	bool Start(const RecvCB &onData, int nworker = 1) { return Start(nworker, onData); }
	bool Stop();

	bool RequestAlloc(const int64_t size, std::function<void(MsgI &msg)> const &onResult);

	bool Send(const MQInfo &remote, const MsgI &msg, const std::string &msg_id, RecvCB &&cb);
	template <class Body>
	bool Send(const MQInfo &remote, BHMsgHead &head, Body &body, RecvCB &&cb) { return Send(remote, MsgI::Serialize(head, body), head.msg_id(), std::move(cb)); }
	bool Send(const MQInfo &remote, std::string &&content, const std::string &msg_id, RecvCB &&cb);

	template <class Body>
	bool Send(const MQInfo &remote, BHMsgHead &head, Body &body) { return Send(remote, MsgI::Serialize(head, body)); }
	bool Send(const MQInfo &remote, std::string &&content);
	bool Send(const MQInfo &remote, const MsgI &imsg) { return SendImpl(remote, imsg); }

	template <class... T>
	bool Send(const MQInfo &remote, const int64_t cmd, T &&...t)
	{
		return SendImpl(remote, cmd, std::forward<decltype(t)>(t)...);
	}

	template <class Body>
	bool SendAndRecv(const MQInfo &remote, BHMsgHead &head, Body &body, MsgI &reply, BHMsgHead &reply_head, const int timeout_ms)
	{
		struct State {
			std::mutex mutex;
			std::condition_variable cv;
			bool canceled = false;
		};

		try {
			std::shared_ptr<State> st(new State);

			auto endtime = std::chrono::steady_clock::now() + std::chrono::milliseconds(timeout_ms);

			auto OnRecv = [st, &reply, &reply_head](ShmSocket &sock, MsgI &msg, BHMsgHead &head) {
				std::unique_lock<std::mutex> lk(st->mutex);
				if (!st->canceled) {
					reply.swap(msg);
					reply_head.Swap(&head);
					st->cv.notify_one();
				} else { // ignore
				}
			};

			std::unique_lock<std::mutex> lk(st->mutex);
			bool sendok = Send(remote, head, body, std::move(OnRecv));
			if (!sendok) {
				LOG_DEBUG() << "send timeout";
			}
			if (sendok && st->cv.wait_until(lk, endtime) == std::cv_status::no_timeout) {
				return true;
			} else {
				st->canceled = true;
				SetLastError(ETIMEDOUT, "timeout");
				return false;
			}
		} catch (...) {
			return false;
		}
	}

	Shm &shm() const { return mq().shm(); }

protected:
	Queue &mq() { return mq_; } // programmer should make sure that mq_ is valid.
	const Queue &mq() const { return mq_; }
	std::mutex &mutex() { return mutex_; }

private:
	bool StopNoLock();
	bool RunningNoLock() { return !workers_.empty(); }

	template <class... Rest>
	bool SendImpl(Rest &&...rest)
	{
		return send_buffer_.Append(std::forward<decltype(rest)>(rest)...);
	}

	std::vector<std::thread> workers_;
	std::mutex mutex_;
	std::atomic<bool> run_;

	Queue mq_;
	template <class Key, class CB>
	class CallbackRecords
	{
		std::unordered_map<Key, CB> store_;

	public:
		bool empty() const { return store_.empty(); }
		bool Store(const Key &id, CB &&cb) { return store_.emplace(id, std::move(cb)).second; }
		bool Pick(const Key &id, CB &cb)
		{
			auto pos = store_.find(id);
			if (pos != store_.end()) {
				cb.swap(pos->second);
				store_.erase(pos);
				return true;
			} else {
				return false;
			}
		}
	};

	Synced<CallbackRecords<std::string, RecvCB>> per_msg_cbs_;
	Synced<CallbackRecords<int, RawRecvCB>> alloc_cbs_;

	// node request center alloc memory.
	int node_proc_index_ = -1;
	int socket_index_ = -1;
	std::atomic<int> alloc_id_;

	SendQ send_buffer_;
};

#endif // end of include guard: SHM_SOCKET_GWTJHBPO