/*****************************************************************************\
     Snes9x - Portable Super Nintendo Entertainment System (TM) emulator.
                This file is licensed under the Snes9x License.
   For further information, consult the LICENSE file in the root directory.
\*****************************************************************************/

#include "snes9x.h"
#include "2xsai.h"

#define ALL_COLOR_MASK	(FIRST_COLOR_MASK | SECOND_COLOR_MASK | THIRD_COLOR_MASK)

#define colorMask		(((~RGB_LOW_BITS_MASK & ALL_COLOR_MASK) << 16) | (~RGB_LOW_BITS_MASK & ALL_COLOR_MASK))
#define qcolorMask		(((~TWO_LOW_BITS_MASK & ALL_COLOR_MASK) << 16) | (~TWO_LOW_BITS_MASK & ALL_COLOR_MASK))
#define lowPixelMask	((RGB_LOW_BITS_MASK << 16) | RGB_LOW_BITS_MASK)
#define qlowpixelMask	((TWO_LOW_BITS_MASK << 16) | TWO_LOW_BITS_MASK)

static inline int GetResult (uint32, uint32, uint32, uint32);
static inline int GetResult1 (uint32, uint32, uint32, uint32, uint32);
static inline int GetResult2 (uint32, uint32, uint32, uint32, uint32);
static inline uint32 INTERPOLATE (uint32, uint32);
static inline uint32 Q_INTERPOLATE (uint32, uint32, uint32, uint32);


static inline int GetResult (uint32 A, uint32 B, uint32 C, uint32 D)
{
	int	x = 0, y = 0, r = 0;

	if (A == C) x += 1; else if (B == C) y += 1;
	if (A == D) x += 1; else if (B == D) y += 1;
	if (x <= 1) r += 1;
	if (y <= 1) r -= 1;

	return (r);
}

static inline int GetResult1 (uint32 A, uint32 B, uint32 C, uint32 D, uint32 E)
{
	int	x = 0, y = 0, r = 0;

	if (A == C) x += 1; else if (B == C) y += 1;
	if (A == D) x += 1; else if (B == D) y += 1;
	if (x <= 1) r += 1;
	if (y <= 1) r -= 1;

	return (r);
}

static inline int GetResult2 (uint32 A, uint32 B, uint32 C, uint32 D, uint32 E)
{
	int	x = 0, y = 0, r = 0;

	if (A == C) x += 1; else if (B == C) y += 1;
	if (A == D) x += 1; else if (B == D) y += 1;
	if (x <= 1) r -= 1;
	if (y <= 1) r += 1;

	return (r);
}

static inline uint32 INTERPOLATE (uint32 A, uint32 B)
{
	return (((A & colorMask) >> 1) + ((B & colorMask) >> 1) + (A & B & lowPixelMask));
}

static inline uint32 Q_INTERPOLATE (uint32 A, uint32 B, uint32 C, uint32 D)
{
	uint32	x = ((A & qcolorMask) >> 2) + ((B & qcolorMask) >> 2) + ((C & qcolorMask) >> 2) + ((D & qcolorMask) >> 2);
	uint32	y = (A & qlowpixelMask) + (B & qlowpixelMask) + (C & qlowpixelMask) + (D & qlowpixelMask);

	y = (y >> 2) & qlowpixelMask;

	return (x + y);
}

bool8 S9xBlit2xSaIFilterInit (void)
{
	return (TRUE);
}

void S9xBlit2xSaIFilterDeinit (void)
{
	return;
}

void SuperEagle (uint8 *srcPtr, int srcRowBytes, uint8 *dstPtr, int dstRowBytes, int width, int height)
{
    uint16	*bP;
    uint32	*dP;
	uint32	nextline = srcRowBytes >> 1;

	for (; height; height--)
	{
	    bP = (uint16 *) srcPtr;
	    dP = (uint32 *) dstPtr;

		for (int i = 0; i < width; i++)
		{
           	uint32	color1, color2, color3, color4, color5, color6;
           	uint32	colorA1, colorA2, colorB1, colorB2, colorS1, colorS2;
           	uint32	product1a, product1b, product2a, product2b;

			colorB1 = *(bP - nextline    );
			colorB2 = *(bP - nextline + 1);

			color4  = *(bP - 1);
			color5  = *(bP    );
			color6  = *(bP + 1);
			colorS2 = *(bP + 2);

			color1  = *(bP + nextline - 1);
			color2  = *(bP + nextline    );
			color3  = *(bP + nextline + 1);
			colorS1 = *(bP + nextline + 2);

			colorA1 = *(bP + nextline + nextline    );
			colorA2 = *(bP + nextline + nextline + 1);

			if (color2 == color6 && color5 != color3)
			{
				product1b = product2a = color2;
				if ((color1 == color2 && color6 == colorS2) || (color2 == colorA1 && color6 == colorB2))
				{
					product1a = INTERPOLATE(color2, color5);
					product1a = INTERPOLATE(color2, product1a);
					product2b = INTERPOLATE(color2, color3);
					product2b = INTERPOLATE(color2, product2b);
				}
				else
				{
					product1a = INTERPOLATE(color5, color6);
					product2b = INTERPOLATE(color2, color3);
				}
			}
			else
			if (color5 == color3 && color2 != color6)
			{
				product2b = product1a = color5;
				if ((colorB1 == color5 && color3 == colorA2) || (color4 == color5 && color3 == colorS1))
				{
					product1b = INTERPOLATE(color5, color6);
					product1b = INTERPOLATE(color5, product1b);
					product2a = INTERPOLATE(color5, color2);
					product2a = INTERPOLATE(color5, product2a);
				}
				else
				{
					product1b = INTERPOLATE(color5, color6);
					product2a = INTERPOLATE(color2, color3);
				}
			}
			else
			if (color5 == color3 && color2 == color6 && color5 != color6)
			{
				int	r = 0;

				r += GetResult(color6, color5, color1,  colorA1);
				r += GetResult(color6, color5, color4,  colorB1);
				r += GetResult(color6, color5, colorA2, colorS1);
				r += GetResult(color6, color5, colorB2, colorS2);

				if (r > 0)
				{
					product1b = product2a = color2;
					product1a = product2b = INTERPOLATE(color5, color6);
				}
				else
				if (r < 0)
				{
					product2b = product1a = color5;
					product1b = product2a = INTERPOLATE(color5, color6);
				}
				else
				{
					product2b = product1a = color5;
					product1b = product2a = color2;
				}
			}
			else
			{
				if ((color2 == color5) || (color3 == color6))
				{
					product1a = color5;
					product2a = color2;
					product1b = color6;
					product2b = color3;
				}
				else
				{
					product1b = product1a = INTERPOLATE(color5, color6);
					product1a = INTERPOLATE(color5, product1a);
					product1b = INTERPOLATE(color6, product1b);

					product2a = product2b = INTERPOLATE(color2, color3);
					product2a = INTERPOLATE(color2, product2a);
					product2b = INTERPOLATE(color3, product2b);
				}
			}

		#ifdef MSB_FIRST
			product1a = (product1a << 16) | product1b;
			product2a = (product2a << 16) | product2b;
		#else
			product1a = product1a | (product1b << 16);
			product2a = product2a | (product2b << 16);
		#endif

			*(dP) = product1a;
			*(dP + (dstRowBytes >> 2)) = product2a;

			bP++;
			dP++;
		}

	    dstPtr += dstRowBytes << 1;
		srcPtr += srcRowBytes;
 	}
}

void _2xSaI (uint8 *srcPtr, int srcRowBytes, uint8 *dstPtr, int dstRowBytes, int width, int height)
{
	uint16 	*bP;
	uint32	*dP;
	uint32	nextline  = srcRowBytes >> 1;

	for (; height; height--)
	{
	    bP = (uint16 *) srcPtr;
	    dP = (uint32 *) dstPtr;

		for (int i = 0; i < width; i++)
		{
			uint32	colorA, colorB, colorC, colorD, colorE, colorF, colorG, colorH, colorI, colorJ, colorK, colorL, colorM, colorN, colorO, colorP;
			uint32	product, product1, product2;

			colorI = *(bP - nextline - 1);
			colorE = *(bP - nextline    );
			colorF = *(bP - nextline + 1);
			colorJ = *(bP - nextline + 2);

			colorG = *(bP - 1);
			colorA = *(bP    );
			colorB = *(bP + 1);
			colorK = *(bP + 2);

			colorH = *(bP + nextline - 1);
			colorC = *(bP + nextline    );
			colorD = *(bP + nextline + 1);
			colorL = *(bP + nextline + 2);

			colorM = *(bP + nextline + nextline - 1);
			colorN = *(bP + nextline + nextline    );
			colorO = *(bP + nextline + nextline + 1);
			colorP = *(bP + nextline + nextline + 2);

			if ((colorA == colorD) && (colorB != colorC))
			{
				if (((colorA == colorE) && (colorB == colorL)) || ((colorA == colorC) && (colorA == colorF) && (colorB != colorE) && (colorB == colorJ)))
					product = colorA;
				else
					product = INTERPOLATE(colorA, colorB);

				if (((colorA == colorG) && (colorC == colorO)) || ((colorA == colorB) && (colorA == colorH) && (colorG != colorC) && (colorC == colorM)))
					product1 = colorA;
				else
					product1 = INTERPOLATE(colorA, colorC);

				product2 = colorA;
			}
			else
			if ((colorB == colorC) && (colorA != colorD))
			{
				if (((colorB == colorF) && (colorA == colorH)) || ((colorB == colorE) && (colorB == colorD) && (colorA != colorF) && (colorA == colorI)))
					product = colorB;
				else
					product = INTERPOLATE(colorA, colorB);

				if (((colorC == colorH) && (colorA == colorF)) || ((colorC == colorG) && (colorC == colorD) && (colorA != colorH) && (colorA == colorI)))
					product1 = colorC;
				else
					product1 = INTERPOLATE(colorA, colorC);

				product2 = colorB;
			}
			else
			if ((colorA == colorD) && (colorB == colorC))
			{
				if (colorA == colorB)
				{
					product  = colorA;
					product1 = colorA;
					product2 = colorA;
				}
				else
				{
					int	r = 0;

					product1 = INTERPOLATE(colorA, colorC);
					product  = INTERPOLATE(colorA, colorB);

					r += GetResult1(colorA, colorB, colorG, colorE, colorI);
					r += GetResult2(colorB, colorA, colorK, colorF, colorJ);
					r += GetResult2(colorB, colorA, colorH, colorN, colorM);
					r += GetResult1(colorA, colorB, colorL, colorO, colorP);

					if (r > 0)
						product2 = colorA;
					else
					if (r < 0)
						product2 = colorB;
					else
						product2 = Q_INTERPOLATE(colorA, colorB, colorC, colorD);
				}
			}
			else
			{
				product2 = Q_INTERPOLATE(colorA, colorB, colorC, colorD);

				if ((colorA == colorC) && (colorA == colorF) && (colorB != colorE) && (colorB == colorJ))
					product  = colorA;
				else
				if ((colorB == colorE) && (colorB == colorD) && (colorA != colorF) && (colorA == colorI))
					product  = colorB;
				else
					product = INTERPOLATE(colorA, colorB);

				if ((colorA == colorB) && (colorA == colorH) && (colorG != colorC) && (colorC == colorM))
					product1 = colorA;
				else
				if ((colorC == colorG) && (colorC == colorD) && (colorA != colorH) && (colorA == colorI))
					product1 = colorC;
				else
					product1 = INTERPOLATE(colorA, colorC);
			}

		#ifdef MSB_FIRST
			product  = (colorA   << 16) | product;
			product1 = (product1 << 16) | product2;
		#else
			product  = colorA   | (product  << 16);
			product1 = product1 | (product2 << 16);
		#endif

			*(dP) = product;
			*(dP + (dstRowBytes >> 2)) = product1;

			bP++;
			dP++;
		}

	    dstPtr += dstRowBytes << 1;
		srcPtr += srcRowBytes;
    }
}

void Super2xSaI (uint8 *srcPtr, int srcRowBytes, uint8 *dstPtr, int dstRowBytes, int width, int height)
{
    uint16	*bP;
	uint32	*dP;
	uint32	nextline = srcRowBytes >> 1;

	for (; height; height--)
	{
		bP = (uint16 *) srcPtr;
	    dP = (uint32 *) dstPtr;

		for (int i = 0; i < width; i++)
		{
           	uint32	color1, color2, color3, color4, color5, color6;
           	uint32	colorA0, colorA1, colorA2, colorA3, colorB0, colorB1, colorB2, colorB3, colorS1, colorS2;
           	uint32	product1a, product1b, product2a, product2b;

			colorB0 = *(bP - nextline - 1);
			colorB1 = *(bP - nextline    );
			colorB2 = *(bP - nextline + 1);
			colorB3 = *(bP - nextline + 2);

			color4  = *(bP - 1);
			color5  = *(bP    );
			color6  = *(bP + 1);
			colorS2 = *(bP + 2);

			color1  = *(bP + nextline - 1);
			color2  = *(bP + nextline    );
			color3  = *(bP + nextline + 1);
			colorS1 = *(bP + nextline + 2);

			colorA0 = *(bP + nextline + nextline - 1);
			colorA1 = *(bP + nextline + nextline    );
			colorA2 = *(bP + nextline + nextline + 1);
			colorA3 = *(bP + nextline + nextline + 2);

			if (color2 == color6 && color5 != color3)
            	product2b = product1b = color2;
			else
			if (color5 == color3 && color2 != color6)
                product2b = product1b = color5;
			else
			if (color5 == color3 && color2 == color6 && color5 != color6)
			{
				int	r = 0;

				r += GetResult(color6, color5, color1,  colorA1);
				r += GetResult(color6, color5, color4,  colorB1);
				r += GetResult(color6, color5, colorA2, colorS1);
				r += GetResult(color6, color5, colorB2, colorS2);

				if (r > 0)
					product2b = product1b = color6;
				else
				if (r < 0)
					product2b = product1b = color5;
				else
					product2b = product1b = INTERPOLATE(color5, color6);
			}
			else
			{
				if (color6 == color3 && color3 == colorA1 && color2 != colorA2 && color3 != colorA0)
					product2b = Q_INTERPOLATE(color3, color3, color3, color2);
				else
				if (color5 == color2 && color2 == colorA2 && colorA1 != color3 && color2 != colorA3)
					product2b = Q_INTERPOLATE(color2, color2, color2, color3);
				else
					product2b = INTERPOLATE(color2, color3);

				if (color6 == color3 && color6 == colorB1 && color5 != colorB2 && color6 != colorB0)
					product1b = Q_INTERPOLATE(color6, color6, color6, color5);
				else
				if (color5 == color2 && color5 == colorB2 && colorB1 != color6 && color5 != colorB3)
					product1b = Q_INTERPOLATE(color6, color5, color5, color5);
				else
					product1b = INTERPOLATE (color5, color6);
			}

			if (color5 == color3 && color2 != color6 && color4 == color5 && color5 != colorA2)
				product2a = INTERPOLATE(color2, color5);
			else
			if (color5 == color1 && color6 == color5 && color4 != color2 && color5 != colorA0)
				product2a = INTERPOLATE(color2, color5);
			else
				product2a = color2;

			if (color2 == color6 && color5 != color3 && color1 == color2 && color2 != colorB2)
				product1a = INTERPOLATE(color2, color5);
			else
			if (color4 == color2 && color3 == color2 && color1 != color5 && color2 != colorB0)
				product1a = INTERPOLATE(color2, color5);
			else
				product1a = color5;

		#ifdef MSB_FIRST
			product1a = (product1a << 16) | product1b;
			product2a = (product2a << 16) | product2b;
		#else
			product1a = product1a | (product1b << 16);
			product2a = product2a | (product2b << 16);
		#endif

			*(dP) = product1a;
			*(dP +(dstRowBytes >> 2)) = product2a;

			bP++;
			dP++;
		}

	    dstPtr += dstRowBytes << 1;
		srcPtr += srcRowBytes;
	}
}