/**

 * vim: set ts=4 :

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

 * SourceMod (C)2004-2007 AlliedModders LLC.  All rights reserved.

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

 *

 * This file is not open source and may not be copied without explicit

 * written permission of AlliedModders LLC.  This file may not be redistributed 

 * in whole or significant part.

 * For information, see LICENSE.txt or http://www.sourcemod.net/license.php

 *

 * Version: $Id$

 */

#include <malloc.h>

#include <string.h>

class CellArray

{

public:

	CellArray(size_t blocksize) : m_Data(NULL), m_BlockSize(blocksize), m_AllocSize(0), m_Size(0)

	{

	}

	~CellArray()

	{

		free(m_Data);

	}

	size_t size() const

	{

		return m_Size;

	}

	cell_t *push()

	{

		if (!GrowIfNeeded(1))

		{

			return NULL;

		}

		cell_t *arr = &m_Data[m_Size * m_BlockSize];

		m_Size++;

		return arr;

	}

	cell_t *at(size_t b) const

	{

		return &m_Data[b * m_BlockSize];

	}

	size_t blocksize() const

	{

		return m_BlockSize;

	}

	void clear()

	{

		m_Size = 0;

	}

	bool swap(size_t item1, size_t item2)

	{

		/* Make sure there is extra space available */

		if (!GrowIfNeeded(1))

		{

			return false;

		}

		cell_t *pri = at(item1);

		cell_t *alt = at(item2);

		/* Get our temporary array 1 after the limit */

		cell_t *temp = &m_Data[m_Size * m_BlockSize];

		memcpy(temp, pri, sizeof(cell_t) * m_BlockSize);

		memcpy(pri, alt, sizeof(cell_t) * m_BlockSize);

		memcpy(alt, temp, sizeof(cell_t) * m_BlockSize);

		return true;

	}

	void remove(size_t index)

	{

		/* If we're at the end, take the easy way out */

		if (index == m_Size - 1)

		{

			m_Size--;

			return;

		}

		/* Otherwise, it's time to move stuff! */

		size_t remaining_indexes = (m_Size - 1) - index;

		cell_t *src = at(index + 1);

		cell_t *dest = at(index);

		memmove(dest, src, sizeof(cell_t) * m_BlockSize * remaining_indexes);

		m_Size--;

	}

	cell_t *insert_at(size_t index)

	{

		/* Make sure it'll fit */

		if (!GrowIfNeeded(1))

		{

			return NULL;

		}

		/* move everything up */

		cell_t *src = at(index);

		cell_t *dst = at(index + 1);

		memmove(dst, src, sizeof(cell_t) * m_BlockSize * m_Size);

		m_Size++;

		return src;

	}

	bool resize(size_t count)

	{

		if (count <= m_Size)

		{

			m_Size = count;

			return true;

		}

		return GrowIfNeeded(m_Size - count);

	}

private:

	bool GrowIfNeeded(size_t count)

	{

		/* Shortcut out if we can store this */

		if (m_Size + count <= m_AllocSize)

		{

			return true;

		}

		/* Set a base allocation size of 8 items */

		if (!m_AllocSize)

		{

			m_AllocSize = 8;

		}

		/* If it's not enough, keep doubling */

		while (m_Size + count > m_AllocSize)

		{

			m_AllocSize *= 2;

		}

		/* finally, allocate the new block */

		if (m_Data)

		{

			m_Data = (cell_t *)realloc(m_Data, sizeof(cell_t) * m_BlockSize * m_AllocSize);

		} else {

			m_Data = (cell_t *)malloc(sizeof(cell_t) * m_BlockSize * m_AllocSize);

		}

		return (m_Data != NULL);

	}

private:

	cell_t *m_Data;

	size_t m_BlockSize;

	size_t m_AllocSize;

	size_t m_Size;

};