/**

 * vim: set ts=4 :

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

 * SourceMod

 * Copyright (C) 2004-2007 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: $Id$

 */

#ifndef _INCLUDE_SOURCEMOD_INTERFACE_DATAPACK_H_

#define _INCLUDE_SOURCEMOD_INTERFACE_DATAPACK_H_

#include <sp_vm_api.h>

/**

 * @file IDataPack.h

 * @brief Contains functions for packing data abstractly to/from plugins.  The wrappers

 * for creating these are contained in ISourceMod.h

 */

namespace SourceMod

{

	/**

	 * @brief Specifies a data pack that can only be read.

	 */

	class IDataReader

	{

	public:

		/**

		 * @brief Resets the position in the data stream to the beginning.

		 */

		virtual void Reset() const =0;

		/**

		 * @brief Retrieves the current stream position.

		 *

		 * @return			Index into the stream.

		 */

		virtual size_t GetPosition() const =0;

		/**

		 * @brief Sets the current stream position.

		 *

		 * @param pos		Index to set the stream at.

		 * @return			True if succeeded, false if out of bounds.

		 */

		virtual bool SetPosition(size_t pos) const =0;

		/**

		 * @brief Reads one cell from the data stream.

		 *

		 * @return			A cell read from the current position.

		 */

		virtual cell_t ReadCell() const =0;

		/**

		 * @brief Reads one float from the data stream.

		 *

		 * @return			A float read from the current position.

		 */

		virtual float ReadFloat() const =0;

		/**

		 * @brief Returns whether or not a specified number of bytes from the current stream

		 *  position to the end can be read.

		 * 

		 * @param bytes		Number of bytes to simulate reading.

		 * @return			True if can be read, false otherwise.

		 */

		virtual bool IsReadable(size_t bytes) const =0;

		/**

		 * @brief Reads a string from the data stream.

		 *

		 * @param len		Optional pointer to store the string length.

		 * @return			Pointer to the string, or NULL if out of bounds.

		 */

		virtual const char *ReadString(size_t *len) const =0;

		/**

		 * @brief Reads the current position as a generic address.

		 *

		 * @return			Pointer to the memory.

		 */

		virtual void *GetMemory() const =0;

		/**

		* @brief Reads the current position as a generic data type.

		*

		* @param size		Optional pointer to store the size of the data type.

		* @return			Pointer to the data, or NULL if out of bounds.

		*/

		virtual void *ReadMemory(size_t *size) const =0;

	};

	/**

	 * @brief Specifies a data pack that can only be written.

	 */

	class IDataPack : public IDataReader

	{

	public:

		/**

		* @brief Resets the used size of the stream back to zero.

		*/

		virtual void ResetSize() =0;

		/**

		 * @brief Packs one cell into the data stream.

		 *

		 * @param cell		Cell value to write.

		 */

		virtual void PackCell(cell_t cell) =0;

		/**

		 * @brief Packs one float into the data stream.

		 *

		 * @param val		Float value to write.

		 */

		virtual void PackFloat(float val) =0;

		/**

		 * @brief Packs one string into the data stream.

		 * The length is recorded as well for buffer overrun protection.

		 *

		 * @param string	String to write.

		 */

		virtual void PackString(const char *string) =0;

		/**

		 * @brief Creates a generic block of memory in the stream.

		 *

		 * Note that the pointer it returns can be invalidated on further

		 * writing, since the stream size may grow.  You may need to double back

		 * and fetch the pointer again.

		 *

		 * @param size		Size of the memory to create in the stream.

		 * @param addr		Optional pointer to store the relocated memory address.

		 * @return			Current position of the stream beforehand.

		 */

		virtual size_t CreateMemory(size_t size, void **addr) =0;

	};

}

#endif //_INCLUDE_SOURCEMOD_INTERFACE_DATAPACK_H_