/*
 * memmappedfile.h
 *
 *  Created on: May 27, 2013
 *      Author: gregor
 */

#ifndef GLTB_MEMMAPPEDFILE_H_
#define GLTB_MEMMAPPEDFILE_H_

#include <string>
#include <vector>

#if defined WIN32
#include <windows.h>
#endif

#include "GLTB/referencedobject.h"
#include "GLTB/refptr.h"
#include "GLTB/weakptr.h"

namespace gltb {
	class MemMappedFile;

	class Mapping : public ReferencedObject {
		friend class MemMappedFile;
	public:
		~Mapping();

		void *getBase() const { return base; };
		long long getSize() const { return size; };
		bool isValid() const { return valid; };
		void syncToDisk(bool synchronous = true) { syncToDisk(base, size, synchronous); };
		void syncToDisk(void *base, unsigned long long size, bool synchronous = true);
		void remove();

	private:
		Mapping(WeakPtr<MemMappedFile> memMappedFile, void *realBase, void *base, unsigned long long realSize, unsigned long long size);

		void *realBase;
		void *base;
		unsigned long long realSize;
		unsigned long long size;
		bool valid;

		WeakPtr<MemMappedFile> memMappedFile;
	};

	class MemMappedFile : public ReferencedObject {
	public:
		struct Mode {
			Mode(bool read, bool write, bool exec) : readable(read), writeable(write), executable(exec) {};

			bool readable;
			bool writeable;
			bool executable;
		};

		MemMappedFile(std::string filename, bool read, bool write, bool exec);
		MemMappedFile(std::string filename, Mode mode);
		MemMappedFile();
		~MemMappedFile();

		RefPtr<Mapping> mapRegion(unsigned long long offset, unsigned long long size);

		bool isOpen() const { return opened; };

		void close();

		void _removeMapping(RefPtr<Mapping> mapping);
#if defined WIN32
		HANDLE _getFileHandle() { return file; };
#endif

	private:
		std::string filename;
		Mode mode;
		bool opened;

		std::vector<WeakPtr<Mapping> > mappings;

#if defined LINUX || defined ANDROID
		int fileID;
#elif defined WIN32
		HANDLE file;
		HANDLE fileMapping;
#endif

		void init();
	};
}

#endif /* GLTB_MEMMAPPEDFILE_H_ */