/*]  Copyright (c) 2009-2010, Charles McGarvey  [**************************
**]  All rights reserved.
*
* vi:ts=4 sw=4 tw=75
*
* Distributable under the terms and conditions of the 2-clause BSD license;
* see the file COPYING for a complete text of the license.
*
**************************************************************************/

#include "hash.hh"
#include "runloop.hh"
#include "timer.hh"


namespace moof {


enum registry_action
{
	lookup,
	set
};

static uint32_t call_registry(runloop*& runloop, registry_action action)
{
	typedef stlplus::hash<uint32_t,moof::runloop*,hash_function> table_t;
	static table_t table;

	uint32_t thread_id = thread::current_identifier();

	static MOOF_DECLARE_MUTEX(table_mutex);
	MOOF_MUTEX_LOCK(table_mutex);

	switch (action)
	{
		case set:
		{
			if (runloop) table[thread_id] = runloop;
			else         table.erase(thread_id);
			break;
		}

		case lookup:
		{
			table_t::iterator it = table.find(thread_id);
			if (it != table.end()) runloop = (*it).second;
			break;
		}
	}

	return thread_id;
}


int runloop::run()
{
#if ENABLE_THREADS
	runloop* runloop = this;
	thread_id_ = call_registry(runloop, set);
#endif

	stop_ = false;
	while (!stop_)
	{
		scalar next_event = SCALAR(0.0);
		{
			MOOF_MUTEX_LOCK(timers_mutex_);

			for (timers_it_ = timers_.begin();
				 timers_it_ != timers_.end();
				 ++timers_it_)
			{
				scalar absolute = (*timers_it_)->fire_if_expired();
				if (next_event == SCALAR(0.0) ||
					(absolute != SCALAR(0.0) && absolute < next_event))
				{
					next_event = absolute;
				}
			}
		}
		timer::sleep(next_event, timer::absolute);
	}

	return code_;
}


runloop::~runloop()
{
	runloop* runloop = 0;
	call_registry(runloop, set);
}


void runloop::stop(int code)
{
	code_ = code;
	stop_ = true;
}


runloop* runloop::current()
{
	runloop* runloop;
	call_registry(runloop, lookup);
	return runloop;
}


void runloop::add_timer(timer* timer)
{
#if ENABLE_THREADS
	if (thread_id_ != thread::current_identifier())
	{
		MOOF_MUTEX_LOCK(timers_mutex_);
		timers_.insert(timer);
		timers_it_ = timers_.end();
	}
	else
#endif
	{
		timers_.insert(timer);
		timers_it_ = timers_.end();
	}
}

void runloop::remove_timer(timer* timer)
{
#if ENABLE_THREADS
	if (thread_id_ != thread::current_identifier())
	{
		MOOF_MUTEX_LOCK(timers_mutex_);
		timers_.erase(timer);
		timers_it_ = timers_.end();
	}
	else
#endif
	{
		timers_.erase(timer);
		timers_it_ = timers_.end();
	}
}


} // namespace moof