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#ifndef _BGFX_PIXEL_BPIXEL_HXX
#define _BGFX_PIXEL_BPIXEL_HXX

#include <sal/types.h>
#include <basegfx/numeric/ftools.hxx>
#include <basegfx/color/bcolor.hxx>

//////////////////////////////////////////////////////////////////////////////
// predeclarations

//////////////////////////////////////////////////////////////////////////////

namespace basegfx
{
	class BPixel
	{
	protected:
		union
		{
			struct
			{
				// bitfield
				unsigned								mnR : 8;		// red intensity
				unsigned								mnG : 8;		// green intensity
				unsigned								mnB : 8;		// blue intensity
				unsigned								mnO : 8;		// opacity, 0 == full transparence
			} maRGBO;
			
			struct
			{
				// bitfield
				unsigned								mnValue : 32;	// all values
			} maCombinedRGBO;
		} maPixelUnion;

	public:
		BPixel()
		{
			maPixelUnion.maCombinedRGBO.mnValue = 0L;
		}

		// use explicit here to make sure everyone knows what he is doing. Values range from
		// 0..255 integer here.
		explicit BPixel(sal_uInt8 nRed, sal_uInt8 nGreen, sal_uInt8 nBlue, sal_uInt8 nOpacity)
		{
			maPixelUnion.maRGBO.mnR = nRed;
			maPixelUnion.maRGBO.mnG = nGreen;
			maPixelUnion.maRGBO.mnB = nBlue;
			maPixelUnion.maRGBO.mnO = nOpacity;
		}

		// constructor from BColor which uses double precision color, so change it
		// to local integer format. It will also be clamped here.
		BPixel(const BColor& rColor, sal_uInt8 nOpacity)
		{
			maPixelUnion.maRGBO.mnR = sal_uInt8((rColor.getRed() * 255.0) + 0.5);
			maPixelUnion.maRGBO.mnG = sal_uInt8((rColor.getGreen() * 255.0) + 0.5);
			maPixelUnion.maRGBO.mnB = sal_uInt8((rColor.getBlue() * 255.0) + 0.5);
			maPixelUnion.maRGBO.mnO = nOpacity;
		}

		// copy constructor
		BPixel(const BPixel& rPixel)
		{
			maPixelUnion.maCombinedRGBO.mnValue = rPixel.maPixelUnion.maCombinedRGBO.mnValue;
		}

		~BPixel()
		{}

		// assignment operator
		BPixel& operator=( const BPixel& rPixel ) 
		{ 
			maPixelUnion.maCombinedRGBO.mnValue = rPixel.maPixelUnion.maCombinedRGBO.mnValue;
			return *this; 
		}

		// data access read
		sal_uInt8 getRed() const { return maPixelUnion.maRGBO.mnR; }
		sal_uInt8 getGreen() const { return maPixelUnion.maRGBO.mnG; }
		sal_uInt8 getBlue() const { return maPixelUnion.maRGBO.mnB; }
		sal_uInt8 getOpacity() const { return maPixelUnion.maRGBO.mnO; }
		sal_uInt32 getRedGreenBlueOpacity() const { return maPixelUnion.maCombinedRGBO.mnValue; }

		// data access write
		void setRed(sal_uInt8 nNew) { maPixelUnion.maRGBO.mnR = nNew; }
		void setGreen(sal_uInt8 nNew) { maPixelUnion.maRGBO.mnG = nNew; }
		void setBlue(sal_uInt8 nNew) { maPixelUnion.maRGBO.mnB = nNew; }
		void setOpacity(sal_uInt8 nNew) { maPixelUnion.maRGBO.mnO = nNew; }
		void setRedGreenBlueOpacity(sal_uInt32 nRedGreenBlueOpacity) { maPixelUnion.maCombinedRGBO.mnValue = nRedGreenBlueOpacity; }
		void setRedGreenBlue(sal_uInt8 nR, sal_uInt8 nG, sal_uInt8 nB) { maPixelUnion.maRGBO.mnR = nR; maPixelUnion.maRGBO.mnG = nG; maPixelUnion.maRGBO.mnB = nB; }

		// comparators
		bool isInvisible() const { return (0 == maPixelUnion.maRGBO.mnO); }
		bool isVisible() const { return (0 != maPixelUnion.maRGBO.mnO); }
		bool isEmpty() const { return isInvisible(); }
		bool isUsed() const { return isVisible(); }

		bool operator==( const BPixel& rPixel ) const 
		{ 
			return (rPixel.maPixelUnion.maCombinedRGBO.mnValue == maPixelUnion.maCombinedRGBO.mnValue);
		}

		bool operator!=( const BPixel& rPixel ) const 
		{ 
			return (rPixel.maPixelUnion.maCombinedRGBO.mnValue != maPixelUnion.maCombinedRGBO.mnValue);
		}

		// empty element
		static const BPixel& getEmptyBPixel();
	};

	//////////////////////////////////////////////////////////////////////////
	// external operators

	inline BPixel minimum(const BPixel& rTupA, const BPixel& rTupB) 
	{ 
		BPixel aMin(
			(rTupB.getRed() < rTupA.getRed()) ? rTupB.getRed() : rTupA.getRed(),
			(rTupB.getGreen() < rTupA.getGreen()) ? rTupB.getGreen() : rTupA.getGreen(),
			(rTupB.getBlue() < rTupA.getBlue()) ? rTupB.getBlue() : rTupA.getBlue(),
			(rTupB.getOpacity() < rTupA.getOpacity()) ? rTupB.getOpacity() : rTupA.getOpacity()); 
		return aMin;
	}

	inline BPixel maximum(const BPixel& rTupA, const BPixel& rTupB) 
	{ 
		BPixel aMax(
			(rTupB.getRed() > rTupA.getRed()) ? rTupB.getRed() : rTupA.getRed(),
			(rTupB.getGreen() > rTupA.getGreen()) ? rTupB.getGreen() : rTupA.getGreen(),
			(rTupB.getBlue() > rTupA.getBlue()) ? rTupB.getBlue() : rTupA.getBlue(),
			(rTupB.getOpacity() > rTupA.getOpacity()) ? rTupB.getOpacity() : rTupA.getOpacity()); 
		return aMax;
	}

	inline BPixel interpolate(const BPixel& rOld1, const BPixel& rOld2, double t) 
	{ 
		if(rOld1 == rOld2)
		{
			return rOld1;
		}
		else if(0.0 >= t)
		{
			return rOld1;
		}
		else if(1.0 <= t)
		{
			return rOld2;
		}
		else
		{
			const sal_uInt32 nFactor(fround(256.0 * t));
			const sal_uInt32 nNegFac(256L - nFactor);
			return BPixel(
				(sal_uInt8)(((sal_uInt32)rOld1.getRed() * nNegFac + (sal_uInt32)rOld2.getRed() * nFactor) >> 8L),
				(sal_uInt8)(((sal_uInt32)rOld1.getGreen() * nNegFac + (sal_uInt32)rOld2.getGreen() * nFactor) >> 8L),
				(sal_uInt8)(((sal_uInt32)rOld1.getBlue() * nNegFac + (sal_uInt32)rOld2.getBlue() * nFactor) >> 8L),
				(sal_uInt8)(((sal_uInt32)rOld1.getOpacity() * nNegFac + (sal_uInt32)rOld2.getOpacity() * nFactor) >> 8L));
		}
	}

	inline BPixel average(const BPixel& rOld1, const BPixel& rOld2) 
	{ 
		if(rOld1 == rOld2)
		{
			return rOld1;
		}
		else
		{
			return BPixel(
				(sal_uInt8)(((sal_uInt32)rOld1.getRed() + (sal_uInt32)rOld2.getRed()) >> 1L),
				(sal_uInt8)(((sal_uInt32)rOld1.getGreen() + (sal_uInt32)rOld2.getGreen()) >> 1L),
				(sal_uInt8)(((sal_uInt32)rOld1.getBlue() + (sal_uInt32)rOld2.getBlue()) >> 1L),
				(sal_uInt8)(((sal_uInt32)rOld1.getOpacity() + (sal_uInt32)rOld2.getOpacity()) >> 1L));
		}
	}
	
	inline BPixel average(const BPixel& rOld1, const BPixel& rOld2, const BPixel& rOld3)
	{ 
		if(rOld1 == rOld2 && rOld2 == rOld3)
		{
			return rOld1;
		}
		else
		{
			return BPixel(
				(sal_uInt8)(((sal_uInt32)rOld1.getRed() + (sal_uInt32)rOld2.getRed() + (sal_uInt32)rOld3.getRed()) / 3L),
				(sal_uInt8)(((sal_uInt32)rOld1.getGreen() + (sal_uInt32)rOld2.getGreen() + (sal_uInt32)rOld3.getGreen()) / 3L),
				(sal_uInt8)(((sal_uInt32)rOld1.getBlue() + (sal_uInt32)rOld2.getBlue() + (sal_uInt32)rOld3.getBlue()) / 3L),
				(sal_uInt8)(((sal_uInt32)rOld1.getOpacity() + (sal_uInt32)rOld2.getOpacity() + (sal_uInt32)rOld3.getOpacity()) / 3L));
		}
	}
} // end of namespace basegfx

#endif /* _BGFX_PIXEL_BPIXEL_HXX */
