/*	EQEmu: EQEmulator

	Copyright (C) 2001-2026 EQEmu Development Team

	This program is free software; you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation; either version 3 of the License, or
	(at your option) any later version.

	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/>.
*/
#pragma once

#include "common/types.h"

#include <string>

namespace EQ {

	//! Memory Backed Shared Memory
	/*!
		Allows us to create shared memory that is backed by a file on both windows and unix platforms that
		works in a consistent manner. Non-copyable.
	*/
	class MemoryMappedFile {
		struct Implementation;
		struct shared_memory_struct;

		//! Underlying data structure.
		struct shared_memory_struct {
			uint32 size;
			unsigned char data[1];
		};
	public:
		//! Constructor
		/*!
			Creates a mmf for the given filename and of size.
		\param filename Actual filename of the mmf.
		\param size Size in bytes of the mmf.
		*/
		MemoryMappedFile(std::string filename, uint32 size);

		//! Constructor
		/*!
			Creates a mmf for the given filename and gets the size based on the existing size.
		\param filename Actual filename of the mmf.
		*/
		MemoryMappedFile(std::string filename);

		//! Destructor
		~MemoryMappedFile();

		//! Get Data Operator
		inline void *operator->() const { return memory_->data; }

		//! Get Data Function
		inline void *Get() const { return memory_->data; }

		//! Get Size Function
		inline uint32 Size() const { return memory_->size; }

		//! Zeros all the memory in the file, and set it to be unloaded
		void ZeroFile();
	private:
		//! Copy Constructor
		MemoryMappedFile(const MemoryMappedFile&);

		//! Assignment Operator
		const MemoryMappedFile& operator=(const MemoryMappedFile&);

		std::string filename_; //!< Filename of this shared memory object
		uint32 size_; //!< Size in bytes of this shared memory object
		shared_memory_struct *memory_; //!< Underlying data of the shared memory object.

		Implementation *imp_; //!< Underlying implementation.
	};
} // EQEmu