/****************************************************************************
Copyright (c) 2010 cocos2d-x.org

http://www.cocos2d-x.org

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
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The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
****************************************************************************/

#include "CCScheduler.h"
#include "ccMacros.h"
#include "support/data_support/utlist.h"
#include "NSMutableArray.h"

#include <assert.h>
namespace   cocos2d {

// data structures

// A list double-linked list used for "updates with priority"
typedef struct _listEntry
{
	struct	_listEntry	*prev, *next;
	SelectorProtocol	*target;		// not retained (retained by hashUpdateEntry)
	int				priority;
	bool				paused;
	
} tListEntry;

typedef struct _hashUpdateEntry
{
	tListEntry			**list;		// Which list does it belong to ?
	tListEntry			*entry;		// entry in the list
	SelectorProtocol	*target;		// hash key (retained)
	UT_hash_handle		hh;
} tHashUpdateEntry;

// Hash Element used for "selectors with interval"
typedef struct _hashSelectorEntry
{
	NSMutableArray<CCTimer*>	*timers;
	SelectorProtocol			*target;	// hash key (retained)
	unsigned int						timerIndex;
	CCTimer						*currentTimer;
	bool						currentTimerSalvaged;
	bool						paused;
	UT_hash_handle				hh;
} tHashSelectorEntry;

// implementation CCTimer

CCTimer* CCTimer::timerWithTarget(SelectorProtocol *pTarget, SEL_SCHEDULE pfnSelector)
{
	CCTimer *pTimer = new CCTimer();

	pTimer->initWithTarget(pTarget, pfnSelector);
	pTimer->autorelease();

	return pTimer;
}

CCTimer* CCTimer::timerWithTarget(SelectorProtocol *pTarget, SEL_SCHEDULE pfnSelector, ccTime fSeconds)
{
	CCTimer *pTimer = new CCTimer();

	pTimer->initWithTarget(pTarget, pfnSelector, fSeconds);
	pTimer->autorelease();

	return pTimer;
}

CCTimer* CCTimer::initWithTarget(SelectorProtocol *pTarget, SEL_SCHEDULE pfnSelector)
{
    return initWithTarget(pTarget, pfnSelector, 0);
}

CCTimer* CCTimer::initWithTarget(SelectorProtocol *pTarget, SEL_SCHEDULE pfnSelector, ccTime fSeconds)
{
	m_pTarget = pTarget;
	m_pfnSelector = pfnSelector;
	m_fElapsed = -1;
	m_fInterval = fSeconds;

	return this;
}

void CCTimer::update(ccTime dt)
{
	if (m_fElapsed == -1)
	{
		m_fElapsed = 0;
	}
	else
	{
		m_fElapsed += dt;
	}

	if (m_fElapsed >= m_fInterval)
	{
		if (m_pfnSelector)
		{
			(m_pTarget->*m_pfnSelector)(m_fElapsed);
			m_fElapsed = 0;
		}
	}
}


// implementation of CCScheduler

static CCScheduler *pSharedScheduler;

CCScheduler::CCScheduler(void)
{
	assert(pSharedScheduler == NULL);
}

CCScheduler::~CCScheduler(void)
{
	unscheduleAllSelectors();

	delete pSharedScheduler;
	pSharedScheduler = NULL;
}

CCScheduler* CCScheduler::getSharedScheduler(void)
{
	if (! pSharedScheduler)
	{
		pSharedScheduler = new CCScheduler();
		pSharedScheduler->init();
	}

	return pSharedScheduler;
}

CCScheduler* CCScheduler::init(void)
{
	m_fTimeScale = 1.0f;

	// used to trigger CCTimer#update
	// m_pfnUpdateSelector = &CCScheduler::update;
	// impMethod = (TICK_IMP) [CCTimer instanceMethodForSelector:updateSelector];

	// updates with priority
	m_pUpdates0List = NULL;
	m_pUpdatesNegList = NULL;
	m_pUpdatesPosList = NULL;
	m_pHashForUpdates = NULL;

	// selectors with interval
	m_pCurrentTarget = NULL;
    m_bCurrentTargetSalvaged = false;
	m_pHashForSelectors = NULL;

	return this;
}

void CCScheduler::removeHashElement(_hashSelectorEntry *pElement)
{
	delete pElement->timers;
	HASH_DEL(m_pHashForSelectors, pElement);
	free(pElement);
}

void CCScheduler::scheduleTimer(CCTimer *pTimer)
{
	assert(false);
}

void CCScheduler::unscheduleTimer(CCTimer *pTimer)
{
	assert(false);
}

void CCScheduler::unscheduleAllTimers()
{
	assert(false);
}

void CCScheduler::scheduleSelector(SEL_SCHEDULE pfnSelector, SelectorProtocol *pTarget, float fInterval, bool bPaused)
{
	assert(pfnSelector != NULL);
	assert(pTarget != NULL);

	tHashSelectorEntry *pElement = NULL;
	HASH_FIND_INT(m_pHashForSelectors, &pTarget, pElement);

	if (! pElement)
	{
		pElement = (tHashSelectorEntry *)calloc(sizeof(*pElement), 1);;
		pElement->target = pTarget;
		HASH_ADD_INT(m_pHashForSelectors, target, pElement);

		// Is this the 1st element ? Then set the pause level to all the selectors of this target
		pElement->paused = bPaused;
	}
	else
	{
		assert(pElement->paused == bPaused);
	}

	if (pElement->timers == NULL)
	{
		pElement->timers = new NSMutableArray<CCTimer*>(10);
	}
    
	// NSMutableArray will increase it's capacity automatically
	//else if( element->timers->num == element->timers->max )
		//ccArrayDoubleCapacity(element->timers);

	CCTimer *pTimer = new CCTimer();
	pTimer->initWithTarget(pTarget, pfnSelector, fInterval);
	pElement->timers->addObject(pTimer);
	pTimer->release();
}

void CCScheduler::unscheduleSelector(SEL_SCHEDULE pfnSelector, SelectorProtocol *pTarget)
{
	// explicity handle nil arguments when removing an object
	if (pTarget == NULL || pfnSelector == NULL)
	{
		return;
	}

	assert(pTarget != NULL);
	assert(pfnSelector != NULL);

	tHashSelectorEntry *pElement = NULL;
	HASH_FIND_INT(m_pHashForSelectors, &pTarget, pElement);

	if (pElement)
	{
		NSMutableArray<CCTimer*>::NSMutableArrayIterator iter;
		unsigned int i;
		for (iter = pElement->timers->begin(), i = 0; iter != pElement->timers->end(); ++iter, ++i)
		{
			CCTimer *pTimer = *iter;

			if (pfnSelector == pTimer->m_pfnSelector)
			{
				if (pTimer == pElement->currentTimer && (! pElement->currentTimerSalvaged))
				{
					pElement->currentTimer->retain();
					pElement->currentTimerSalvaged = true;
				}

				pElement->timers->removeObjectAtIndex(i);

				// update timerIndex in case we are in tick:, looping over the actions
				if (pElement->timerIndex >= i)
				{
					pElement->timerIndex--;
				}

				if (pElement->timers->count() == 0)
				{
					if (m_pCurrentTarget == pElement)
					{
						m_bCurrentTargetSalvaged = true;
					}
					else
					{
						removeHashElement(pElement);
					}
				}

				return;
			}
		}
	}
}

void CCScheduler::priorityIn(tListEntry **ppList, SelectorProtocol *pTarget, int nPriority, bool bPaused)
{
	tListEntry *pListElement = (tListEntry *)malloc(sizeof(*pListElement));

	pListElement->target = pTarget;
	pListElement->priority = nPriority;
	pListElement->paused = bPaused;
	pListElement->next = pListElement->prev = NULL;
	// listElement->impMethod = (TICK_IMP) [target methodForSelector:updateSelector];

	// empey list ?
	if (! *ppList)
	{
		DL_APPEND(*ppList, pListElement);
	}
	else
	{
		bool bAdded = false;

		for (tListEntry *pElement = *ppList; pElement; pElement = pElement->next)
		{
			if (nPriority < pElement->priority)
			{
				if (pElement == *ppList)
				{
					DL_PREPEND(*ppList, pListElement);
				}
				else
				{
					pListElement->next = pElement;
					pListElement->prev = pElement->prev;

					pElement->prev->next = pListElement;
					pElement->prev = pListElement;
				}

				bAdded = true;
				break;
			}
		}

		// Not added? priority has the higher value. Append it.
		if (! bAdded)
		{
			DL_APPEND(*ppList, pListElement);
		}
	}

	// update hash entry for quick access
	tHashUpdateEntry *pHashElement = (tHashUpdateEntry *)calloc(sizeof(*pHashElement), 1);
	pHashElement->target = pTarget;
	pHashElement->list = ppList;
	pHashElement->entry = pListElement;
	HASH_ADD_INT(m_pHashForUpdates, target, pHashElement);
}

void CCScheduler::appendIn(_listEntry **ppList, SelectorProtocol *pTarget, bool bPaused)
{
	tListEntry *pListElement = (tListEntry *)malloc(sizeof(*pListElement));
;

	pListElement->target = pTarget;
	pListElement->paused = bPaused;
	// listElement->impMethod = (TICK_IMP) [target methodForSelector:updateSelector];

	DL_APPEND(*ppList, pListElement);

	// update hash entry for quicker access
	tHashUpdateEntry *pHashElement = (tHashUpdateEntry *)calloc(sizeof(*pHashElement), 1);
	// hashElement->target = [target retain];
	pHashElement->list = ppList;
	pHashElement->entry = pListElement;
	HASH_ADD_INT(m_pHashForUpdates, target, pHashElement);
}

void CCScheduler::scheduleUpdateForTarget(SelectorProtocol *pTarget, int nPriority, bool bPaused)
{
#if COCOS2D_DEBUG >= 1
	tHashUpdateEntry *pHashElement = NULL;
	HASH_FIND_INT(m_pHashForUpdates, &target, pHashElement);
	assert(pHashElement == NULL);
#endif

	// most of the updates are going to be 0, that's way there
	// is an special list for updates with priority 0
	if (nPriority == 0)
	{
		appendIn(&m_pUpdates0List, pTarget, bPaused);
	} else
	if (nPriority < 0)
	{
		priorityIn(&m_pUpdatesNegList, pTarget, nPriority, bPaused);
	}
	else
	{
		// priority > 0
		priorityIn(&m_pUpdatesPosList, pTarget, nPriority, bPaused);
	}
}

void CCScheduler::unscheduleUpdateForTarget(SelectorProtocol *pTarget)
{
	if (pTarget == NULL)
	{
		return;
	}

	tHashUpdateEntry *pElement = NULL;
	HASH_FIND_INT(m_pHashForUpdates, &pTarget, pElement);
	if (pElement)
	{
		// list entry
		DL_DELETE(*pElement->list, pElement->entry);
		free(pElement->entry);

		// hash entry
		HASH_DEL(m_pHashForUpdates, pElement);
		free(pElement);
	}
}

void CCScheduler::unscheduleAllSelectors(void)
{
	// Custom Selectors
    tHashSelectorEntry *pElement;
	for (pElement = m_pHashForSelectors; pElement != NULL;)
	{
		pElement = (tHashSelectorEntry *)pElement->hh.next;
		unscheduleAllSelectorsForTarget(pElement->target);
	}

	// Updates selectors
	tListEntry *pEntry, *pTmp;
	DL_FOREACH_SAFE(m_pUpdates0List, pEntry, pTmp)
	{
		unscheduleUpdateForTarget(pEntry->target);
	}
	DL_FOREACH_SAFE(m_pUpdatesNegList, pEntry, pTmp)
	{
        unscheduleUpdateForTarget(pEntry->target);
	}
	DL_FOREACH_SAFE(m_pUpdatesPosList, pEntry, pTmp)
	{
        unscheduleUpdateForTarget(pEntry->target);
	}
}

void CCScheduler::unscheduleAllSelectorsForTarget(SelectorProtocol *pTarget)
{
	// explicit NULL handling
	if (pTarget == NULL)
	{
		return;
	}

	// Custom Selectors
	tHashSelectorEntry *pElement = NULL;
	HASH_FIND_INT(m_pHashForSelectors, &pTarget, pElement);

	if (pElement)
	{
		if (pElement->timers->containsObject(pElement->currentTimer)
			&& (! pElement->currentTimerSalvaged))
		{
			pElement->currentTimer->retain();
			pElement->currentTimerSalvaged = true;
		}
		pElement->timers->removeAllObjects();

		if (m_pCurrentTarget == pElement)
		{
			m_bCurrentTargetSalvaged = true;
		}
		else
		{
			removeHashElement(pElement);
		}
	}

	// update selector
	unscheduleUpdateForTarget(pTarget);
}

void CCScheduler::resumeTarget(SelectorProtocol *pTarget)
{
	assert(pTarget != NULL);

	// custom selectors
	tHashSelectorEntry *pElement = NULL;
	HASH_FIND_INT(m_pHashForSelectors, &pTarget, pElement);
	if (pElement)
	{
		pElement->paused = false;
	}

	// update selector
	tHashUpdateEntry *pElementUpdate = NULL;
	HASH_FIND_INT(m_pHashForUpdates, &pTarget, pElementUpdate);
	if (pElementUpdate)
	{
		assert(pElementUpdate->entry != NULL);
		pElementUpdate->entry->paused = false;
	}
}

void CCScheduler::pauseTarget(SelectorProtocol *pTarget)
{
	assert(pTarget != NULL);

	// custom selectors
	tHashSelectorEntry *pElement = NULL;
	HASH_FIND_INT(m_pHashForSelectors, &pTarget, pElement);
	if (pElement)
	{
		pElement->paused = true;
	}

	// update selector
	tHashUpdateEntry *pElementUpdate = NULL;
	HASH_FIND_INT(m_pHashForUpdates, &pTarget, pElementUpdate);
	if (pElementUpdate)
	{
		assert(pElementUpdate->entry != NULL);
		pElementUpdate->entry->paused = true;
	}
}

// main loop
void CCScheduler::tick(ccTime dt)
{
	if (m_fTimeScale != 1.0f)
	{
		dt *= m_fTimeScale;
	}

	// Iterate all over the Updates selectors
	tListEntry *pEntry, *pTmp;

	// updates with priority < 0
	DL_FOREACH_SAFE(m_pUpdatesNegList, pEntry, pTmp)
	{
		if (! pEntry->paused)
		{
			pEntry->target->update(dt);
		}
	}

	// updates with priority == 0
	DL_FOREACH_SAFE(m_pUpdates0List, pEntry, pTmp)
	{
		if (! pEntry->paused)
		{
			pEntry->target->update(dt);
		}
	}

	// updates with priority > 0
	DL_FOREACH_SAFE(m_pUpdatesPosList, pEntry, pTmp)
	{
		if (! pEntry->paused)
		{
			pEntry->target->update(dt);
		}
	}

	// Interate all over the custom selectors
	for (tHashSelectorEntry *elt = m_pHashForSelectors; elt != NULL; )
	{
		m_pCurrentTarget = elt;
		m_bCurrentTargetSalvaged = false;

		if (! m_pCurrentTarget->paused)
		{
			// The 'timers' array may change while inside this loop
			for (elt->timerIndex = 0; elt->timerIndex < elt->timers->count(); ++(elt->timerIndex))
			{
				elt->currentTimer = elt->timers->getObjectAtIndex(elt->timerIndex);
				elt->currentTimerSalvaged = false;

				elt->currentTimer->update(dt);

				if (elt->currentTimerSalvaged)
				{
					// The currentTimer told the remove itself. To prevent the timer from
					// accidentally deallocating itself before finishing its step, we retained
					// it. Now that step is done, it's safe to release it.
					elt->currentTimer->release();
				}

				elt->currentTimer = NULL;
			}
		}

		// elt, at this moment, is still valid
		// so it is safe to ask this here (issue #490)
		elt = (tHashSelectorEntry *)elt->hh.next;

		// only delete currentTarget if no actions were scheduled during the cycle (issue #481)
		if (m_bCurrentTargetSalvaged && m_pCurrentTarget->timers->count() == 0)
		{
			removeHashElement(m_pCurrentTarget);
		}
	}

	m_pCurrentTarget = NULL;
}

void CCScheduler::purgeSharedScheduler(void)
{
	pSharedScheduler->release();
}
}//namespace   cocos2d