/*
 Derived from source code of TrueCrypt 7.1a, which is
 Copyright (c) 2008-2012 TrueCrypt Developers Association and which is governed
 by the TrueCrypt License 3.0.

 Modifications and additions to the original source code (contained in this file)
 and all other portions of this file are Copyright (c) 2013-2016 IDRIX
 and are governed by the Apache License 2.0 the full text of which is
 contained in the file License.txt included in VeraCrypt binary and source
 code distribution packages.
*/

#ifndef TC_HEADER_Volume_VolumeLayout
#define TC_HEADER_Volume_VolumeLayout

#include "Platform/Platform.h"
#include "Volume/EncryptionAlgorithm.h"
#include "Volume/EncryptionMode.h"
#include "Volume/Pkcs5Kdf.h"
#include "VolumeHeader.h"

namespace VeraCrypt
{
	class VolumeLayout;
	typedef list < shared_ptr <VolumeLayout> > VolumeLayoutList;

	class VolumeLayout
	{
	public:
		virtual ~VolumeLayout ();

		static VolumeLayoutList GetAvailableLayouts (VolumeType::Enum type = VolumeType::Unknown);
		virtual int GetBackupHeaderOffset () const { return BackupHeaderOffset; } // Positive value: offset from the start of host, negative: offset from the end
		virtual uint64 GetDataOffset (uint64 volumeHostSize) const = 0;
		virtual uint64 GetDataSize (uint64 volumeHostSize) const = 0;
		virtual shared_ptr <VolumeHeader> GetHeader ();
		virtual int GetHeaderOffset () const { return HeaderOffset; } // Positive value: offset from the start of host, negative: offset from the end
		virtual uint32 GetHeaderSize () const { return HeaderSize; }
		virtual uint64 GetMaxDataSize (uint64 volumeSize) const = 0;
		virtual EncryptionAlgorithmList GetSupportedEncryptionAlgorithms () const { return SupportedEncryptionAlgorithms; }
		virtual Pkcs5KdfList GetSupportedKeyDerivationFunctions (bool truecryptMode) const { return Pkcs5Kdf::GetAvailableAlgorithms(truecryptMode); }
		virtual EncryptionModeList GetSupportedEncryptionModes () const { return SupportedEncryptionModes; }
		virtual VolumeType::Enum GetType () const { return Type; }
		virtual bool HasBackupHeader () const = 0;
		virtual bool HasDriveHeader () const { return false; }
		virtual void SetHeader (shared_ptr <VolumeHeader> header) { Header = header; }

	protected:
		VolumeLayout ();

		EncryptionAlgorithmList SupportedEncryptionAlgorithms;
		EncryptionModeList SupportedEncryptionModes;

		int BackupHeaderOffset;
		int HeaderOffset;
		uint32 HeaderSize;
		VolumeType::Enum Type;

		shared_ptr <VolumeHeader> Header;

	private:
		VolumeLayout (const VolumeLayout &);
		VolumeLayout &operator= (const VolumeLayout &);
	};


	class VolumeLayoutV1Normal : public VolumeLayout
	{
	public:
		VolumeLayoutV1Normal ();
		virtual ~VolumeLayoutV1Normal () { }

		virtual int GetBackupHeaderOffset () const { throw NotApplicable (SRC_POS); }
		virtual uint64 GetDataOffset (uint64 volumeHostSize) const;
		virtual uint64 GetDataSize (uint64 volumeHostSize) const;
		virtual uint64 GetMaxDataSize (uint64 volumeSize) const { throw NotApplicable (SRC_POS); }
		virtual bool HasBackupHeader () const { return false; }

	private:
		VolumeLayoutV1Normal (const VolumeLayoutV1Normal &);
		VolumeLayoutV1Normal &operator= (const VolumeLayoutV1Normal &);
	};


	class VolumeLayoutV2Normal : public VolumeLayout
	{
	public:
		VolumeLayoutV2Normal ();
		virtual ~VolumeLayoutV2Normal () { }

		virtual uint64 GetDataOffset (uint64 volumeHostSize) const;
		virtual uint64 GetDataSize (uint64 volumeHostSize) const;
		virtual uint64 GetMaxDataSize (uint64 volumeSize) const;
		virtual bool HasBackupHeader () const { return true; }

	private:
		VolumeLayoutV2Normal (const VolumeLayoutV2Normal &);
		VolumeLayoutV2Normal &operator= (const VolumeLayoutV2Normal &);
	};


	class VolumeLayoutV2Hidden : public VolumeLayout
	{
	public:
		VolumeLayoutV2Hidden ();
		virtual ~VolumeLayoutV2Hidden () { }

		virtual uint64 GetDataOffset (uint64 volumeHostSize) const;
		virtual uint64 GetDataSize (uint64 volumeHostSize) const;
		virtual uint64 GetMaxDataSize (uint64 volumeSize) const;
		virtual bool HasBackupHeader () const { return true; }

	private:
		VolumeLayoutV2Hidden (const VolumeLayoutV2Hidden &);
		VolumeLayoutV2Hidden &operator= (const VolumeLayoutV2Hidden &);
	};


	class VolumeLayoutSystemEncryption : public VolumeLayout
	{
	public:
		VolumeLayoutSystemEncryption ();
		virtual ~VolumeLayoutSystemEncryption () { }

		virtual int GetBackupHeaderOffset () const { throw NotApplicable (SRC_POS); }
		virtual uint64 GetDataOffset (uint64 volumeHostSize) const;
		virtual uint64 GetDataSize (uint64 volumeHostSize) const;
		virtual uint64 GetMaxDataSize (uint64 volumeSize) const { throw NotApplicable (SRC_POS); }
		virtual Pkcs5KdfList GetSupportedKeyDerivationFunctions (bool truecryptMode) const;
		virtual bool HasBackupHeader () const { return false; }
		virtual bool HasDriveHeader () const { return true; }

	private:
		VolumeLayoutSystemEncryption (const VolumeLayoutSystemEncryption &);
		VolumeLayoutSystemEncryption &operator= (const VolumeLayoutSystemEncryption &);
	};
}

#endif // TC_HEADER_Volume_VolumeLayout