#include "MemPool.h"
#include <algorithm>

NAMESPACE_MAS_BEGIN

tzc::Mutex MemPool::_mutex;
MemPool * MemPool::_instance = nullptr;

MemPool::MemPool()
{

}

MemPool::~MemPool()
{
	this->Dispose();
}

MemPool * MemPool::Instance()
{
	if (!_instance)
	{
		_mutex.Lock();
		if (!_instance)
		{
			_instance = new MemPool();
		}
		_mutex.Unlock();
	}

	return _instance;
}

void MemPool::DestroyInstance()
{
	_mutex.Lock();
	TZ_delete(_instance);
	_mutex.Unlock();
}

TZ_INT MemPool::Initialize()
{
	for (TZ_INT idx = 1; idx <= BLOCK_LIST_COUNT; ++idx)
	{
		TZ_Uint32 blockSize = (MIN_BLOCK_SIZE << (idx - 1));
		TZ_Uint32 blockCount =
			(idx < BLOCK_LIST_COUNT ? (1 << (BLOCK_LIST_COUNT - 1 - idx)) : 1);

		std::list<void *> blockList;

		for (TZ_INT cnt = 1; cnt <= blockCount; ++cnt)
		{
			void * memBlock = std::malloc(blockSize);

			if (nullptr == memBlock)
			{
				TZLogWarn("malloc memory for size %u failed, "
						"error is %d!!!", blockSize, errno);

				return MEC_FAILED;
			}

			blockList.push_back(memBlock);
		}

		m_memDepot.push_back(blockList);
	}

	TZLogInfo("initialize memory pool succeed~~~");

	return MEC_OK;
}

TZ_INT MemPool::Dispose()
{
	tzc::ScopedLock lock(m_lock);

	for (TZ_INT idx = 0; idx < m_memDepot.size(); ++idx)
	{
		std::list<void *>::iterator iter;

		for (iter = m_memDepot[idx].begin(); iter != m_memDepot[idx].end(); ++iter)
		{
			void * memBlock = * iter;

			TZ_free(memBlock);
		}

		m_memDepot[idx].clear();
	}

	m_memDepot.clear();

	TZLogInfo("memory pool dispose succeed~~~~");

	return MEC_OK;
}

void * MemPool::AllocAvailMem(TZ_Uint32 expect)
{
	tzc::ScopedLock lock(m_lock);

	for (TZ_INT idx = 0; idx < BLOCK_LIST_COUNT; ++idx)
	{
		if (expect <= (MIN_BLOCK_SIZE << idx))
		{
			if (m_memDepot[idx].empty())
			{
				TZLogDebug(2, "the memory list %d is empty!!!", idx);

				continue;
			}

			void * rst = m_memDepot[idx].front();

			m_memDepot[idx].pop_front();

			TZLogInfo("tang: expect %u, idx %d, rst %p, size %d~~~~",
			 		expect, idx, rst, m_memDepot[idx].size());

			TZLogDebug(2, "get memblock 0x%x, expect %d~~~, size %d",
				rst, expect, (MIN_BLOCK_SIZE << idx));

			return rst;
		}
	}

	TZLogWarn("get memory block for size %u failed!!!", expect);
	return nullptr;
}

TZ_INT MemPool::ReturnFreeMem(void * memBlock, TZ_Uint32 memSize)
{
	tzc::ScopedLock lock(m_lock);

	for (TZ_INT idx = 0; idx < BLOCK_LIST_COUNT; ++idx)
	{
		if (memSize <= (MIN_BLOCK_SIZE << idx))
		{
			std::list<void *>::iterator iter =
				std::find(m_memDepot[idx].begin(),
						m_memDepot[idx].end(),
						memBlock);

			if (iter != m_memDepot[idx].end())
			{
				TZLogWarn("return repeat memBlock 0x%x!!!", memBlock);

				return MEC_DUPLICATED;
			}

			m_memDepot[idx].push_back(memBlock);

			TZLogDebug(10, "return memBlock 0x%x, size %d~~~",
				memBlock, (MIN_BLOCK_SIZE << idx));

			return MEC_OK;
		}
	}

	TZLogWarn("illegal memory block 0x%x!!!", memBlock);

	return MEC_NULL_OBJ;
}

TZ_Uint32 MemPool::GetAvailCount(TZ_Uint32 expect)
{
	tzc::ScopedLock lock(m_lock);
	if (expect <= MIN_BLOCK_SIZE)
	{
		return m_memDepot[0].size();
	}

	for (TZ_INT idx = BLOCK_LIST_COUNT; idx != 0; --idx)
	{
		if (expect > (MIN_BLOCK_SIZE << (idx - 1)))
		{
			return m_memDepot[idx].size();
		}
	}

	return 0;
}

NAMESPACE_MAS_END