//-----------------------------------------------------------------------------
//
//	TimerThread.cpp
//
//  Timer for scheduling future events
//
//	Copyright (c) 2017 h3ctrl <h3ctrl@gmail.com>
//
//	SOFTWARE NOTICE AND LICENSE
//
//	This file is part of OpenZWave.
//
//	OpenZWave is free software: you can redistribute it and/or modify
//	it under the terms of the GNU Lesser General Public License as published
//	by the Free Software Foundation, either version 3 of the License,
//	or (at your option) any later version.
//
//	OpenZWave is distributed in the hope that it will be useful,
//	but WITHOUT ANY WARRANTY; without even the implied warranty of
//	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//	GNU Lesser General Public License for more details.
//
//	You should have received a copy of the GNU Lesser General Public License
//	along with OpenZWave.  If not, see <http://www.gnu.org/licenses/>.
//
//-----------------------------------------------------------------------------

#include "TimerThread.h"
#include "Utils.h"
#include "platform/Log.h"
#include "Driver.h"

namespace OpenZWave
{
	namespace Internal
	{

//-----------------------------------------------------------------------------
// <TimerThread::TimerThreadEntryPoint>
// Main entry point for the timer thread.
//-----------------------------------------------------------------------------
		void TimerThread::TimerThreadEntryPoint(Internal::Platform::Event* _exitEvent, void* _context)
		{
			TimerThread* timer = (TimerThread*) _context;
			if (timer)
			{
				timer->TimerThreadProc(_exitEvent);
			}
		}

//-----------------------------------------------------------------------------
// <TimerThread::TimerThread>
// Constructor.
//-----------------------------------------------------------------------------
		TimerThread::TimerThread(Driver *_driver) :
//m_driver( _driver ),
				m_timerEvent(new Internal::Platform::Event()), m_timerMutex(new Internal::Platform::Mutex()), m_timerTimeout(Internal::Platform::Wait::Timeout_Infinite)
		{
		}

//-----------------------------------------------------------------------------
// <TimerThread::~TimerThread>
// Destructor.
//-----------------------------------------------------------------------------
		TimerThread::~TimerThread()
		{
			{
				LockGuard LG(m_timerMutex);
				for (list<TimerEventEntry *>::iterator it = m_timerEventList.begin(); it != m_timerEventList.end(); ++it)
				{
					delete (*it);
				}
			}
			m_timerMutex->Release();
			m_timerEvent->Release();
		}

//-----------------------------------------------------------------------------
// <TimerThread::TimerThreadProc>
// Thread for timer based actions
//-----------------------------------------------------------------------------
		void TimerThread::TimerThreadProc(Internal::Platform::Event* _exitEvent)
		{
			Log::Write(LogLevel_Info, "Timer: thread starting");

			Internal::Platform::Wait* waitObjects[2];
			waitObjects[0] = _exitEvent;
			waitObjects[1] = m_timerEvent;
			uint32 count = 2;

			// Initially no timer events so infinite timeout.
			m_timerTimeout = Internal::Platform::Wait::Timeout_Infinite;

			while (1)
			{
				Log::Write(LogLevel_Detail, "Timer: waiting with timeout %d ms", m_timerTimeout);
				int32 res = Internal::Platform::Wait::Multiple(waitObjects, count, m_timerTimeout);

				if (res == 0)
				{
					// Exit has been signalled
					return;

				}
				else
				{
					// Timeout or new entry to timer list.
					m_timerTimeout = Internal::Platform::Wait::Timeout_Infinite;

					// Go through all waiting actions, and see if any need to be performed.
					LockGuard LG(m_timerMutex);
					list<TimerEventEntry *>::iterator it = m_timerEventList.begin();
					while (it != m_timerEventList.end())
					{
						int32 tr = (*it)->timestamp.TimeRemaining();
						if (tr <= 0)
						{
							// Expired so perform action and remove from list.
							Log::Write(LogLevel_Info, "Timer: delayed event");
							TimerEventEntry *te = *(it++);
							te->instance->TimerFireEvent(te);
						}
						else
						{
							// Time remaining.
							m_timerTimeout = (m_timerTimeout == Internal::Platform::Wait::Timeout_Infinite) ? tr : std::min(m_timerTimeout, tr);
							++it;
						}
					}
					m_timerEvent->Reset();
				}
			} // while( 1 )
		}

//-----------------------------------------------------------------------------
// <TimerThread::TimerSetEvent>
//-----------------------------------------------------------------------------
		TimerThread::TimerEventEntry* TimerThread::TimerSetEvent(int32 _milliseconds, TimerCallback _callback, Timer *_instance, uint32 id)
		{
			Log::Write(LogLevel_Info, "Timer: adding event in %d ms", _milliseconds);
			TimerEventEntry *te = new TimerEventEntry();
			te->timestamp.SetTime(_milliseconds);
			te->callback = _callback;
			te->instance = _instance;
			te->id = id;
			// Don't want driver thread and timer thread accessing list at the same time.
			LockGuard LG(m_timerMutex);
			m_timerEventList.push_back(te);
			m_timerEvent->Set();
			return te;
		}

//-----------------------------------------------------------------------------
// <TimerThread::TimerDelEvent>
// Delete the Specific Timer
//-----------------------------------------------------------------------------

		void TimerThread::TimerDelEvent(TimerEventEntry *te)
		{
			LockGuard LG(m_timerMutex);
			list<TimerEventEntry *>::iterator it = find(m_timerEventList.begin(), m_timerEventList.end(), te);
			if (it != m_timerEventList.end())
			{
				delete ((*it));
				m_timerEventList.erase(it);
			}
			else
			{
				Log::Write(LogLevel_Warning, "Cant Find TimerEvent to Delete in TimerDelEvent");
			}
		}

//-----------------------------------------------------------------------------
// <Timer::Timer>
// Constuctor for Timer SubClass with Driver passed in
//-----------------------------------------------------------------------------
		Timer::Timer(Driver *_driver) :
				m_driver(_driver)
		{
		}
		;
//-----------------------------------------------------------------------------
// <Timer::Timer>
// Default Constuctor for Timer SubClass
//-----------------------------------------------------------------------------

		Timer::Timer() :
				m_driver(NULL)
		{

		}
		;
//-----------------------------------------------------------------------------
// <Timer::~Timer>
// Deconstuctor for Timer SubClass
//-----------------------------------------------------------------------------

		Timer::~Timer()
		{
			TimerDelEvents();
		}

//-----------------------------------------------------------------------------
// <Timer::TimerSetEvent>
// Create a new TimerCallback
//-----------------------------------------------------------------------------
		TimerThread::TimerEventEntry* Timer::TimerSetEvent(int32 _milliseconds, TimerThread::TimerCallback _callback, uint32 id)
		{
			if (m_driver)
			{
				TimerThread::TimerEventEntry *te = m_driver->GetTimer()->TimerSetEvent(_milliseconds, _callback, this, id);
				if (te)
				{
					m_timerEventList.push_back(te);
					return te;
				}
				Log::Write(LogLevel_Warning, "Could Not Register Timer Callback");
				return NULL;
			}
			else
			{
				Log::Write(LogLevel_Warning, "Driver Not Set for TimerThread");
				return NULL;
			}
		}

//-----------------------------------------------------------------------------
// <Timer::TimerDelEvents>
// Delete all TimerEvents associated with this instance
//-----------------------------------------------------------------------------
		void Timer::TimerDelEvents()
		{
			if (m_driver)
			{
				list<TimerThread::TimerEventEntry *>::iterator it = m_timerEventList.begin();
				while (it != m_timerEventList.end())
				{
					m_driver->GetTimer()->TimerDelEvent((*it));
					it = m_timerEventList.erase(it);
				}
			}
			else
			{
				Log::Write(LogLevel_Warning, "Driver Not Set for Timer");
			}

		}
//-----------------------------------------------------------------------------
// <Timer::SetDriver>
// Associate this instance with a Driver
//-----------------------------------------------------------------------------
		void Timer::SetDriver(Driver *_driver)
		{
			m_driver = _driver;
		}
//-----------------------------------------------------------------------------
// <Timer::TimerDelEvent>
// Delete a specific TimerEvent
//-----------------------------------------------------------------------------
		void Timer::TimerDelEvent(TimerThread::TimerEventEntry *te)
		{
			if (m_driver)
			{
				list<TimerThread::TimerEventEntry *>::iterator it = find(m_timerEventList.begin(), m_timerEventList.end(), te);
				if (it != m_timerEventList.end())
				{
					m_driver->GetTimer()->TimerDelEvent((*it));
					m_timerEventList.erase(it);
				}
				else
				{
					Log::Write(LogLevel_Warning, "Cant Find TimerEvent to Delete in TimerDelEvent");
				}
			}
			else
			{
				Log::Write(LogLevel_Warning, "Driver Not Set for Timer");
				return;
			}

		}

//-----------------------------------------------------------------------------
// <Timer::TimerDelEvent>
// Delete a specific TimerEvent
//-----------------------------------------------------------------------------
		void Timer::TimerDelEvent(uint32 id)
		{
			if (m_driver)
			{
				for (list<TimerThread::TimerEventEntry *>::iterator it = m_timerEventList.begin(); it != m_timerEventList.end(); it++)
				{
					if ((*it)->id == id)
					{
						m_driver->GetTimer()->TimerDelEvent((*it));
						m_timerEventList.erase(it);
						return;
					}
				}
				Log::Write(LogLevel_Warning, "Cant Find TimerEvent %d to Delete in TimerDelEvent", id);
				return;
			}
			else
			{
				Log::Write(LogLevel_Warning, "Driver Not Set for TimerThread");
				return;
			}

		}

//-----------------------------------------------------------------------------
// <Timer::TimerFireEvent>
// Execute a Callback
//-----------------------------------------------------------------------------
		void Timer::TimerFireEvent(TimerThread::TimerEventEntry *te)
		{
			te->callback(te->id);
			TimerDelEvent(te);
		}
	} // namespace Internal
} // namespace OpenZWave