#ifndef STREAM_BUFFER__H_
#define STREAM_BUFFER__H_

#ifdef _WIN32
#pragma once
#endif


class HStreamBuffer : public HObject
{
public:
	HStreamBuffer(size_t nSize)
	{
		m_pBuffer = (char *)malloc(nSize);	//...??? 2048 : because of openssl buffer overflow?
		m_nBufferSize = nSize;
		
		m_pBufferHead = m_pBuffer;
		m_pBufferTail = m_pBuffer;
		m_nStoredSize = 0;
		m_nRemainSize = m_nBufferSize;
	}

	~HStreamBuffer()
	{
		free(m_pBuffer);
	}

	inline char * Head() { return m_pBufferHead; }
	inline char * Tail() { return m_pBufferTail; }
	inline size_t Size() { return m_nBufferSize; }
	inline size_t StoredSize() { return m_nStoredSize; }
	inline size_t RemainSize() { return m_nRemainSize; }
	
	inline bool MoveTail(size_t nSize)
	{
		if (nSize > m_nRemainSize)
			return false;

		m_pBufferTail += nSize;
		m_nStoredSize += nSize;
		m_nRemainSize -= nSize;

		return true;
	}

	inline bool Pop(size_t nSize)
	{
		if (nSize > m_nStoredSize)
			return false;

		m_nStoredSize -= nSize;
		
		if (m_nStoredSize == 0)
		{
			m_pBufferHead = m_pBuffer;
			m_pBufferTail = m_pBuffer;
			m_nRemainSize = m_nBufferSize;
		}
		else
		{
			m_pBufferHead += nSize;
		}

		return true;
	}

	inline bool PopAndRewind(size_t nSize)
	{
		if (nSize > m_nStoredSize)
			return false;

		m_nStoredSize -= nSize;
		memcpy(m_pBufferHead, m_pBufferHead + nSize, m_nStoredSize);
		m_pBufferTail = m_pBufferHead + m_nStoredSize;
		m_nRemainSize += nSize;

		return true;
	}

	inline bool Store(const char * pData, size_t nSize)
	{
		if (nSize > m_nRemainSize)
			return false;

		memcpy(m_pBufferTail, pData, nSize);
		m_pBufferTail += nSize;
		m_nStoredSize += nSize;
		m_nRemainSize -= nSize;

		return true;
	}

	inline void Reset()
	{
		m_pBufferHead = m_pBuffer;
		m_pBufferTail = m_pBuffer;
		m_nStoredSize = 0;
		m_nRemainSize = m_nBufferSize;
	}

	inline int MemCmp(const void * p, size_t n)
	{
		return memcmp(m_pBufferHead, p, n);
	}

	inline int Find(const char ch, size_t offset, size_t n = 0)
	{
		if (n == 0)
			n = m_nStoredSize;

		for (size_t i = offset; i < n; i++)
		{
			if (m_pBufferHead[i] == ch)
				return (int)i;
		}

		return -1;
	}

protected:
	char * m_pBuffer;
	char * m_pBufferHead;
	char * m_pBufferTail;

	size_t m_nBufferSize;
	size_t m_nStoredSize;
	size_t m_nRemainSize;	
};

#endif	// STREAM_BUFFER__H_