/*==LICENSE==*

CyanWorlds.com Engine - MMOG client, server and tools
Copyright (C) 2011 Cyan Worlds, Inc.

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/>.

Additional permissions under GNU GPL version 3 section 7

If you modify this Program, or any covered work, by linking or
combining it with any of RAD Game Tools Bink SDK, Autodesk 3ds Max SDK,
NVIDIA PhysX SDK, Microsoft DirectX SDK, OpenSSL library, Independent
JPEG Group JPEG library, Microsoft Windows Media SDK, or Apple QuickTime SDK
(or a modified version of those libraries),
containing parts covered by the terms of the Bink SDK EULA, 3ds Max EULA,
PhysX SDK EULA, DirectX SDK EULA, OpenSSL and SSLeay licenses, IJG
JPEG Library README, Windows Media SDK EULA, or QuickTime SDK EULA, the
licensors of this Program grant you additional
permission to convey the resulting work. Corresponding Source for a
non-source form of such a combination shall include the source code for
the parts of OpenSSL and IJG JPEG Library used as well as that of the covered
work.

You can contact Cyan Worlds, Inc. by email legal@cyan.com
 or by snail mail at:
      Cyan Worlds, Inc.
      14617 N Newport Hwy
      Mead, WA   99021

*==LICENSE==*/

#ifndef plLoadMask_inc
#define plLoadMask_inc

#include "hsTypes.h"

template <class T> class hsTArray;
class hsStream;

class plLoadMask
{
public:
	enum {
		kMaxCap = 1
	};
protected:
	static UInt8	fGlobalQuality;
	static UInt8	fGlobalCapability;
	union {
		UInt8			fQuality[kMaxCap+1];
		UInt16			fMask;
	};

	static void SetGlobalQuality(int q) { fGlobalQuality = IBitToMask(q); }
	static void SetGlobalCapability(int c) { if( c > kMaxCap ) c = kMaxCap; else if( c < 0 ) c = 0; fGlobalCapability = c; }

	static UInt8 IBitToMask(int b) { hsAssert(b<8, "LoadMask: bit too large for byte"); return (1 << b); }

	friend class plQuality;
public:
	// Change this to a for loop on kMaxCap+1 if we ever get more caps.
	plLoadMask() { fQuality[0] = fQuality[1] = 0xff; }
	plLoadMask(UInt8 qLo, UInt8 qHi) { fQuality[0] = qLo; fQuality[1] = qHi; }
	~plLoadMask() {}

	hsBool		DontLoad() const { return !(fQuality[fGlobalCapability] & fGlobalQuality); }

	hsBool		NeverLoads() const { return !(fQuality[0] && fQuality[1]); }

	hsBool		IsUsed() const { return (fQuality[0] != UInt8(-1)) || (fQuality[1] != UInt8(-1));	}

	hsBool		MatchesQuality(int q) const { return (IBitToMask(q) & (fQuality[0] | fQuality[1])) != 0; }
	hsBool		MatchesCapability(int c) const { return fQuality[c] != 0; }
	hsBool		MatchesQualityAndCapability(int q, int c) const { return IBitToMask(q) & fQuality[c]; }

	hsBool		MatchesCurrentQuality() const { return MatchesQuality(fGlobalQuality); }
	hsBool		MatchesCurrentCapability() const { return MatchesCapability(fGlobalCapability); }
	hsBool		MatchesCurrent() const { return !DontLoad(); }

	UInt8		GetQualityMask(int cap) const { return fQuality[cap]; }

	plLoadMask&		SetMask(UInt8 lo, UInt8 hi) { fQuality[0] = lo; fQuality[1] = hi; return *this; }
	plLoadMask&		SetNever() { return SetMask(0,0); }
	plLoadMask&		SetAlways() { return SetMask(UInt8(-1), UInt8(-1)); }

	plLoadMask& operator|=(const plLoadMask& m) { fMask |= m.fMask; return *this; }
	plLoadMask& operator&=(const plLoadMask& m) { fMask &= m.fMask; return *this; }

	int operator==(const plLoadMask& m) const { return fMask == m.fMask; }
	int operator!=(const plLoadMask& m) const { return !(*this == m); }

	// Only useful for sorting.
	int operator<(const plLoadMask& m) const { return fMask < m.fMask; }

	friend plLoadMask operator|(const plLoadMask& lhs, const plLoadMask& rhs) { plLoadMask r(lhs); r |= rhs; return r; }
	friend plLoadMask operator&(const plLoadMask& lhs, const plLoadMask& rhs) { plLoadMask r(lhs); r &= rhs; return r; }

	void		Read(hsStream* s);
	void		Write(hsStream* s) const;

	static const plLoadMask		kAlways;


	// Input lists are in order of preference, i.e. if rep[0] and rep[1] are both loadable based
	// on the current settings, only rep[0] will be loaded. This implies some rules
	// to avoid wasted reps (reps that would never get loaded). Basically:
	//	if( i < j ) then
	//		(quals[i] > quals[j]) || (caps[i] > caps[j])
	//
	// It doesn't break anything if that condition isn't met, it just means
	// the latter one will never get loaded (have a load mask of zero).
	// So, just to be a pal, we'll detect that condition and return based on it.
	// i.e. Return true on invalid input (something will never get loaded).
	// 
	// You can also pre-validate your input with ValidateReps, and/or validate
	// the output with ValidateMasks. The return value is a bitmask of which
	// items in the list had problems, so return of zero means A-OK.
	//
	static hsBool ComputeRepMasks(int num, const int quals[], const int caps[], plLoadMask masks[]);
	static UInt32 ValidateReps(int num, const int quals[], const int caps[]);
	static UInt32 ValidateMasks(int num, plLoadMask masks[]);
};

#endif // plLoadMask_inc