/*
 * =====================================================================================
 *
 *       Filename:  center_main.cc
 *
 *    Description:  
 *
 *        Version:  1.0
 *        Created:  2021年04月13日 16时16分26秒
 *       Revision:  none
 *       Compiler:  gcc
 *
 *         Author:  Li Chao (), lichao@aiotlink.com
 *   Organization:  
 *
 * =====================================================================================
 */
#include "app_arg.h"
#include "box.h"
#include "center.h"
#include "defs.h"
#include "log.h"
#include "signalhandle.h"
#include <boost/interprocess/sync/named_mutex.hpp>
#include <chrono>
#include <thread>
using namespace std::chrono_literals;
using namespace bhome_shm;

namespace
{
const std::string kCenterRunningFlag = "bh_center_single_flag_0";

class InstanceFlag
{

public:
	InstanceFlag(SharedMemory &shm, const std::string &name) :
	    shm_(shm), name_(name), run_(false) {}
	~InstanceFlag() { Stop(); }

	bool TryStartAsFirstInstance()
	{
		if (run_) {
			return true;
		}

		auto mtx(shm_.FindOrCreate<Mutex>(name_ + "_mutex_0"));
		auto time_stamp(shm_.FindOrCreate<int64_t>(name_ + "_timestamp_0", 0));

		if (mtx && time_stamp) {
			Guard lock(*mtx);
			auto now = NowSec();
			LOG_DEBUG() << "old: " << *time_stamp << ", now: " << now;
			if (now > *time_stamp + 10) {
				*time_stamp = now;
				auto UpdateTime = [this, time_stamp]() {
					while (run_) {
						std::this_thread::sleep_for(1s);
						*time_stamp = NowSec();
					}
				};
				run_.store(true);
				std::thread(UpdateTime).swap(worker_);
				return true;
			}
		}
		return false;
	}

private:
	void Stop()
	{
		run_.store(false);
		if (worker_.joinable()) {
			worker_.join();
		}
	}

	std::thread worker_;
	SharedMemory &shm_;
	std::string name_;
	std::atomic<bool> run_;
};

} // namespace
int center_main(int argc, const char *argv[])
{
	AppArg args(argc, argv);
	if (args.Has("remove")) {
		SharedMemory::Remove(BHomeShmName());
		return 0;
	}

	ns_log::AddLog("/opt/vasystem/valog/bhshmq_center.log");
	auto lvl = args.Get("log", "info");
	if (strcasecmp(lvl.c_str(), "trace") == 0) { ns_log::ResetLogLevel(ns_log::LogLevel::trace); }
	if (strcasecmp(lvl.c_str(), "debug") == 0) { ns_log::ResetLogLevel(ns_log::LogLevel::debug); }
	if (strcasecmp(lvl.c_str(), "info") == 0) { ns_log::ResetLogLevel(ns_log::LogLevel::info); }
	if (strcasecmp(lvl.c_str(), "warning") == 0) { ns_log::ResetLogLevel(ns_log::LogLevel::warning); }
	if (strcasecmp(lvl.c_str(), "error") == 0) { ns_log::ResetLogLevel(ns_log::LogLevel::error); }
	if (strcasecmp(lvl.c_str(), "fatal") == 0) { ns_log::ResetLogLevel(ns_log::LogLevel::fatal); }

	auto &shm = BHomeShm();
	if (!CenterInit(shm)) {
		auto msg = "init memory error.";
		LOG_FATAL() << msg;
		printf("%s\n", msg);
		exit(0);
	}
	GlobalInit(shm);

	InstanceFlag inst(shm, kCenterRunningFlag);
	if (!inst.TryStartAsFirstInstance()) {
		auto msg = "another instance is running, exit.";
		LOG_INFO() << msg;
		printf("%s\n", msg);
		return 0;
	}

	if (args.Has("daemon") || args.Has("d")) {
		int r = daemon(0, 0); // TODO center control msg to close itself.
	}

	BHCenter center(shm);
	center.Start();

	auto msg = "center started ...";
	LOG_INFO() << msg;
	printf("%s\n", msg);
	WaitForSignals({SIGINT, SIGTERM});
	center.Stop();
	LOG_INFO() << "center stopped.";
	return 0;
}

namespace
{
static bool install = BoxInstall("bhshmq_center", center_main, "bhome center program.");
}