/**

  * vim: set ts=4 :

  * =============================================================================

  * SourceMod

  * Copyright (C) 2004-2008 AlliedModders LLC.  All rights reserved.

  * =============================================================================

  *

  * This program is free software; you can redistribute it and/or modify it under

  * the terms of the GNU General Public License, version 3.0, as published by the

  * Free Software Foundation.

  * 

  * This program 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 General Public License for more

  * details.

  *

  * You should have received a copy of the GNU General Public License along with

  * this program.  If not, see <http://www.gnu.org/licenses/>.

  *

  * As a special exception, AlliedModders LLC gives you permission to link the

  * code of this program (as well as its derivative works) to "Half-Life 2," the

  * "Source Engine," the "SourcePawn JIT," and any Game MODs that run on software

  * by the Valve Corporation.  You must obey the GNU General Public License in

  * all respects for all other code used.  Additionally, AlliedModders LLC grants

  * this exception to all derivative works.  AlliedModders LLC defines further

  * exceptions, found in LICENSE.txt (as of this writing, version JULY-31-2007),

  * or <http://www.sourcemod.net/license.php>.

  *

  * Version: $Id$

  */

 #include <time.h>

 #include "TimerSys.h"

 #include "ForwardSys.h"

 #include "sourcemm_api.h"

 #include "frame_hooks.h"

 #include "ConVarManager.h"

 #define TIMER_MIN_ACCURACY		0.1

 TimerSystem g_Timers;

 double g_fUniversalTime = 0.0f;

 float g_fGameStartTime = 0.0f;	/* Game game start time, non-universal */

 double g_fTimerThink = 0.0f;		/* Timer's next think time */

 const double *g_pUniversalTime = &g_fUniversalTime;

 ConVar *mp_timelimit = NULL;

 int g_TimeLeftMode = 0;

 ConVar sm_time_adjustment("sm_time_adjustment", "0", 0, "Adjusts the server time in seconds");

 inline double GetSimulatedTime()

 {

 	return g_fUniversalTime;

 }

 time_t GetAdjustedTime(time_t *buf)

 {

 	time_t val = time(NULL) + sm_time_adjustment.GetInt();

 	if (buf)

 	{

 		*buf = val;

 	}

 	return val;

 }

 class DefaultMapTimer : 

 	public IMapTimer,

 	public SMGlobalClass,

 	public IConVarChangeListener

 {

 public:

 	DefaultMapTimer()

 	{

 		m_bInUse = false;

 	}

 	void OnSourceModLevelChange(const char *mapName)

 	{

 		g_fGameStartTime = 0.0f;

 	}

 	int GetMapTimeLimit()

 	{

 		return mp_timelimit->GetInt();

 	}

 	void SetMapTimerStatus(bool enabled)

 	{

 		if (enabled && !m_bInUse)

 		{

 			Enable();

 		} 

 		else if (!enabled && m_bInUse)

 		{

 			Disable();

 		}

 		m_bInUse = enabled;

 	}

 	void ExtendMapTimeLimit(int extra_time)

 	{

 		if (extra_time == 0)

 		{

 			mp_timelimit->SetValue(0);

 			return;

 		}

 		extra_time /= 60;

 		mp_timelimit->SetValue(mp_timelimit->GetInt() + extra_time);

 	}

 	void OnConVarChanged(ConVar *pConVar, const char *oldValue, float flOldValue)

 	{

 		g_Timers.MapTimeLeftChanged();

 	}

 private:

 	void Enable()

 	{

 		g_ConVarManager.AddConVarChangeListener("mp_timelimit", this);

 	}

 	void Disable()

 	{

 		g_ConVarManager.RemoveConVarChangeListener("mp_timelimit", this);

 	}

 private:

 	bool m_bInUse;

 } s_DefaultMapTimer;

 /**

  * If the ticking process has run amok (should be impossible), we 

  * take care of this by "skipping" the in-between time, to prevent 

  * a bazillion times from firing on accident.  This has the result  

  * that a drastic jump in time will continue acting normally.  Users 

  * may not expect this, but... I think it is the best solution.

  */

 inline double CalcNextThink(double last, float interval)

 {

 	if (g_fUniversalTime - last - interval <= TIMER_MIN_ACCURACY)

 	{

 		return last + interval;

 	}

 	else

 	{

 		return g_fUniversalTime + interval;

 	}

 }

 void ITimer::Initialize(ITimedEvent *pCallbacks, float fInterval, float fToExec, void *pData, int flags)

 {

 	m_Listener = pCallbacks;

 	m_Interval = fInterval;

 	m_ToExec = fToExec;

 	m_pData = pData;

 	m_Flags = flags;

 	m_InExec = false;

 	m_KillMe = false;

 }

 TimerSystem::TimerSystem()

 {

 	m_pMapTimer = NULL;

 	m_bHasMapTickedYet = false;

 	m_bHasMapSimulatedYet = false;

 	m_fLastTickedTime = 0.0f;

 }

 TimerSystem::~TimerSystem()

 {

 	CStack<ITimer *>::iterator iter;

 	for (iter=m_FreeTimers.begin(); iter!=m_FreeTimers.end(); iter++)

 	{

 		delete (*iter);

 	}

 	m_FreeTimers.popall();

 }

 void TimerSystem::OnSourceModAllInitialized()

 {

 	g_ShareSys.AddInterface(NULL, this);

 	m_pOnGameFrame = g_Forwards.CreateForward("OnGameFrame", ET_Ignore, 0, NULL);

 	m_pOnMapTimeLeftChanged = g_Forwards.CreateForward("OnMapTimeLeftChanged", ET_Ignore, 0, NULL);

 }

 void TimerSystem::OnSourceModGameInitialized()

 {

 	mp_timelimit = icvar->FindVar("mp_timelimit");

 	if (m_pMapTimer == NULL && mp_timelimit != NULL)

 	{

 		SetMapTimer(&s_DefaultMapTimer);

 	}

 }

 void TimerSystem::OnSourceModShutdown()

 {

 	SetMapTimer(NULL);

 	g_Forwards.ReleaseForward(m_pOnGameFrame);

 	g_Forwards.ReleaseForward(m_pOnMapTimeLeftChanged);

 }

 void TimerSystem::OnSourceModLevelEnd()

 {

 	m_bHasMapTickedYet = false;

 	m_bHasMapSimulatedYet = false;

 }

 void TimerSystem::GameFrame(bool simulating)

 {

 	if (simulating && m_bHasMapTickedYet)

 	{

 		g_fUniversalTime += gpGlobals->curtime - m_fLastTickedTime;

 		if (!m_bHasMapSimulatedYet)

 		{

 			m_bHasMapSimulatedYet = true;

 			MapTimeLeftChanged();

 		}

 	}

 	else 

 	{

 		g_fUniversalTime += gpGlobals->interval_per_tick;

 	}

 	m_fLastTickedTime = gpGlobals->curtime;

 	m_bHasMapTickedYet = true;

 	if (g_fUniversalTime >= g_fTimerThink)

 	{

 		RunFrame();

 		g_fTimerThink = CalcNextThink(g_fTimerThink, TIMER_MIN_ACCURACY);

 	}

 	RunFrameHooks(simulating);

 	if (m_pOnGameFrame->GetFunctionCount())

 	{

 		m_pOnGameFrame->Execute(NULL);

 	}

 }

 void TimerSystem::RunFrame()

 {

 	ITimer *pTimer;

 	TimerIter iter;

 	double curtime = GetSimulatedTime();

 	for (iter=m_SingleTimers.begin(); iter!=m_SingleTimers.end(); )

 	{

 		pTimer = (*iter);

 		if (curtime >= pTimer->m_ToExec)

 		{

 			pTimer->m_InExec = true;

 			pTimer->m_Listener->OnTimer(pTimer, pTimer->m_pData);

 			pTimer->m_Listener->OnTimerEnd(pTimer, pTimer->m_pData);

 			iter = m_SingleTimers.erase(iter);

 			m_FreeTimers.push(pTimer);

 		} 

 		else 

 		{

 			break;

 		}

 	}

 	ResultType res;

 	for (iter=m_LoopTimers.begin(); iter!=m_LoopTimers.end(); )

 	{

 		pTimer = (*iter);

 		if (curtime >= pTimer->m_ToExec)

 		{

 			pTimer->m_InExec = true;

 			res = pTimer->m_Listener->OnTimer(pTimer, pTimer->m_pData);

 			if (pTimer->m_KillMe || (res == Pl_Stop))

 			{

 				pTimer->m_Listener->OnTimerEnd(pTimer, pTimer->m_pData);

 				iter = m_LoopTimers.erase(iter);

 				m_FreeTimers.push(pTimer);

 				continue;

 			}

 			pTimer->m_InExec = false;

 			pTimer->m_ToExec = CalcNextThink(pTimer->m_ToExec, pTimer->m_Interval);

 		}

 		iter++;

 	}

 }

 ITimer *TimerSystem::CreateTimer(ITimedEvent *pCallbacks, float fInterval, void *pData, int flags)

 {

 	ITimer *pTimer;

 	TimerIter iter;

 	float to_exec = GetSimulatedTime() + fInterval;

 	if (m_FreeTimers.empty())

 	{

 		pTimer = new ITimer;

 	} else {

 		pTimer = m_FreeTimers.front();

 		m_FreeTimers.pop();

 	}

 	pTimer->Initialize(pCallbacks, fInterval, to_exec, pData, flags);

 	if (flags & TIMER_FLAG_REPEAT)

 	{

 		m_LoopTimers.push_back(pTimer);

 		goto return_timer;

 	}

 	if (m_SingleTimers.size() >= 1)

 	{

 		iter = --m_SingleTimers.end();

 		if ((*iter)->m_ToExec <= to_exec)

 		{

 			goto normal_insert_end;

 		}

 	}

 	for (iter=m_SingleTimers.begin(); iter!=m_SingleTimers.end(); iter++)

 	{

 		if ((*iter)->m_ToExec >= to_exec)

 		{

 			m_SingleTimers.insert(iter, pTimer);

 			goto return_timer;

 		}

 	}

 normal_insert_end:

 	m_SingleTimers.push_back(pTimer);

 return_timer:

 	return pTimer;

 }

 void TimerSystem::FireTimerOnce(ITimer *pTimer, bool delayExec)

 {

 	ResultType res;

 	if (pTimer->m_InExec)

 	{

 		return;

 	}

 	pTimer->m_InExec = true;

 	res = pTimer->m_Listener->OnTimer(pTimer, pTimer->m_pData);

 	if (!(pTimer->m_Flags & TIMER_FLAG_REPEAT))

 	{

 		pTimer->m_Listener->OnTimerEnd(pTimer, pTimer->m_pData);

 		m_SingleTimers.remove(pTimer);

 		m_FreeTimers.push(pTimer);

 	} 

 	else 

 	{

 		if ((res != Pl_Stop) && !pTimer->m_KillMe)

 		{

 			if (delayExec)

 			{

 				pTimer->m_ToExec = GetSimulatedTime() + pTimer->m_Interval;

 			}

 			pTimer->m_InExec = false;

 			return;

 		}

 		pTimer->m_Listener->OnTimerEnd(pTimer, pTimer->m_pData);

 		m_LoopTimers.remove(pTimer);

 		m_FreeTimers.push(pTimer);

 	}

 }

 void TimerSystem::KillTimer(ITimer *pTimer)

 {

 	if (pTimer->m_KillMe)

 	{

 		return;

 	}

 	if (pTimer->m_InExec)

 	{

 		pTimer->m_KillMe = true;

 		return;

 	}

 	pTimer->m_InExec = true; /* The timer it's not really executed but this check needs to be done */

 	pTimer->m_Listener->OnTimerEnd(pTimer, pTimer->m_pData);

 	if (pTimer->m_Flags & TIMER_FLAG_REPEAT)

 	{

 		m_LoopTimers.remove(pTimer);

 	} else {

 		m_SingleTimers.remove(pTimer);

 	}

 	m_FreeTimers.push(pTimer);

 }

 CStack<ITimer *> s_tokill;

 void TimerSystem::RemoveMapChangeTimers()

 {

 	ITimer *pTimer;

 	TimerIter iter;

 	for (iter=m_SingleTimers.begin(); iter!=m_SingleTimers.end(); iter++)

 	{

 		pTimer = (*iter);

 		if (pTimer->m_Flags & TIMER_FLAG_NO_MAPCHANGE)

 		{

 			s_tokill.push(pTimer);

 		}

 	}

 	for (iter=m_LoopTimers.begin(); iter!=m_LoopTimers.end(); iter++)

 	{

 		pTimer = (*iter);

 		if (pTimer->m_Flags & TIMER_FLAG_NO_MAPCHANGE)

 		{

 			s_tokill.push(pTimer);

 		}

 	}

 	while (!s_tokill.empty())

 	{

 		KillTimer(s_tokill.front());

 		s_tokill.pop();

 	}

 }

 IMapTimer *TimerSystem::SetMapTimer(IMapTimer *pTimer)

 {

 	IMapTimer *old = m_pMapTimer;

 	m_pMapTimer = pTimer;

 	if (m_pMapTimer)

 	{

 		m_pMapTimer->SetMapTimerStatus(true);

 	}

 	if (old)

 	{

 		old->SetMapTimerStatus(false);

 	}

 	return old;

 }

 IMapTimer *TimerSystem::GetMapTimer()

 {

 	return m_pMapTimer;

 }

 void TimerSystem::MapTimeLeftChanged()

 {

 	m_pOnMapTimeLeftChanged->Execute(NULL);

 }

 void TimerSystem::NotifyOfGameStart(float offset)

 {

 	g_fGameStartTime = gpGlobals->curtime + offset;

 }

 float TimerSystem::GetTickedTime()

 {

 	return g_fUniversalTime;

 }

 bool TimerSystem::GetMapTimeLeft(float *time_left)

 {

 	if (!m_pMapTimer)

 	{

 		return false;

 	}

 	int time_limit;

 	if (!m_bHasMapSimulatedYet || (time_limit = m_pMapTimer->GetMapTimeLimit()) < 1)

 	{

 		*time_left = -1.0f;

 	}

 	else

 	{

 		*time_left = (g_fGameStartTime + time_limit * 60.0f) - gpGlobals->curtime;

 	}

 	return true;

 }