/* +-------------------------------------------------------------------+ */
/* | Copyright 1993, David Koblas (koblas@netcom.com)                  | */
/* |                                                                   | */
/* | Permission to use, copy, modify, and to distribute this software  | */
/* | and its documentation for any purpose is hereby granted without   | */
/* | fee, provided that the above copyright notice appear in all       | */
/* | copies and that both that copyright notice and this permission    | */
/* | notice appear in supporting documentation.  There is no           | */
/* | representations about the suitability of this software for        | */
/* | any purpose.  this software is provided "as is" without express   | */
/* | or implied warranty.                                              | */
/* |                                                                   | */
/* +-------------------------------------------------------------------+ */

#include <X11/Intrinsic.h>
#include "image.h"
#include "hash.h"
#include "palette.h"
#include "misc.h"

#define HASH_SIZE	128

/*
**  Faster macros for "fast" Image <-> XImage loops
*/

#define ZINDEX(x, y, img) (((y) * img->bytes_per_line) + \
			   (((x) * img->bits_per_pixel) >> 3))

#define ZINDEX32(x, y, img) ((y) * img->bytes_per_line) + ((x) << 2)
#define ZINDEX8(x, y, img)  ((y) * img->bytes_per_line) + (x)
#define ZINDEX1(x, y, img)  ((y) * img->bytes_per_line) + ((x) >> 3)

static void imageToPixmapLoop(Display*, Image*, Palette*, XImage*, Pixmap*);

/*
 * The functions below are written from X11R5 MIT's code (XImUtil.c)
 *
 * The idea is to have faster functions than the standard XGetPixel function
 * to scan the image data. Indeed we can speed up things by suppressing tests
 * performed for each pixel. We do exactly the same tests but at the image
 * level. Assuming that we use only ZPixmap images.
 */

static unsigned long low_bits_table[] = {
    0x00000000, 0x00000001, 0x00000003, 0x00000007,
    0x0000000f, 0x0000001f, 0x0000003f, 0x0000007f,
    0x000000ff, 0x000001ff, 0x000003ff, 0x000007ff,
    0x00000fff, 0x00001fff, 0x00003fff, 0x00007fff,
    0x0000ffff, 0x0001ffff, 0x0003ffff, 0x0007ffff,
    0x000fffff, 0x001fffff, 0x003fffff, 0x007fffff,
    0x00ffffff, 0x01ffffff, 0x03ffffff, 0x07ffffff,
    0x0fffffff, 0x1fffffff, 0x3fffffff, 0x7fffffff,
    0xffffffff
};

/*
**  Actuall Image routines
**
**
*/


Image *ImageNew(int width, int height)
{
	Image	*image = XtNew(Image);

	image->refCount = 1;
	image->isBW = False;
	image->isGrey = False;
	image->cmapPacked = False;
	image->cmapSize = 0;
	image->cmapData = NULL;
	image->width = width;
	image->height = height;
	image->sourceColormap = None;
	image->sourcePixmap = None;
	image->sourceMask = None;
	image->scale = 3;
	if (width == 0 || height == 0)
		image->data = NULL;
	else
		image->data = (unsigned char *)XtMalloc(width * height * sizeof(char) * 3);
	image->maskData = NULL;
	return image;
}

Image *ImageNewCmap(int width, int height, int size)
{
	Image	*image = ImageNew(0, 0);

	if (size == 0)
		image->scale = 3;
	else if (size <= 256)
		image->scale = 1;
	else
		image->scale = sizeof(short) / sizeof(char);

	image->width    = width;
	image->height   = height;
	image->data     = (unsigned char *)XtMalloc(width * height * sizeof(char) * image->scale);
	if (size != 0)
		image->cmapData = (unsigned char *)XtMalloc(size * sizeof(char) * 3);
	image->cmapSize = size;

	return image;
}

Image *ImageNewBW(int width, int height)
{
	Image	*image = ImageNewCmap(width, height, 2);

	image->cmapData[0] = 0;
	image->cmapData[1] = 0;
	image->cmapData[2] = 0;
	image->cmapData[3] = 255;
	image->cmapData[4] = 255;
	image->cmapData[5] = 255;

	return image;
}

Image *ImageNewGrey(int width, int height)
{
	int	i;
	Image	*image = ImageNewCmap(width, height, 256);

	image->isGrey = True;
	for (i = 0; i < image->cmapSize; i++) {
		image->cmapData[i * 3 + 0] = i;
		image->cmapData[i * 3 + 1] = i;
		image->cmapData[i * 3 + 2] = i;
	}

	return image;
}

void ImageMakeMask(Image *image)
{
	image->maskData = (unsigned char *)XtMalloc(image->width * image->height * sizeof(char));
}


void ImageDelete(Image *image)
{
	image->refCount--;
	if (image->refCount > 0)
		return;

	if (image->cmapSize > 0 && image->cmapData != NULL)
		XtFree((XtPointer)image->cmapData);
	if (image->data != NULL)
		XtFree((XtPointer)image->data);
	if (image->maskData != NULL)
		XtFree((XtPointer)image->maskData);
	XtFree((XtPointer)image);
}

/*
**  Convert a colormap image into a RGB image
**    useful for writers which only deal with RGB and not
**    colormaps
*/
Image *ImageToRGB(Image *image)
{
	unsigned char	*ip, *op;
	Image	*out;
	int	x, y;

	if (image->cmapSize == 0) {
		image->refCount++;
		return image;
	}
	 
	out = ImageNew(image->width, image->height);
	op = image->data;

	for (y = 0; y < image->height; y++) { 
		for (x = 0; x < image->width; x++) { 
			ip = ImagePixel(image, x, y);
			*op++ = *ip++;
			*op++ = *ip++;
			*op++ = *ip++;
		}
	}

	out->isBW   = image->isBW;
	out->isGrey = False;
	out->width  = image->width;
	out->height = image->height;

	image->cmapPacked = False;

	return out;
}

/*
**  Create a nice image for writing routines.
*/

static int  writeCMP(XColor *a, XColor *b)
{
	return a->pixel - b->pixel;
}

Image *PixmapToImage(Widget w, Pixmap pix, Colormap cmap)
{
	XImage		*xim;
	Image		*image;
	Display		*dpy = XtDisplay(w);
        int             x, y;
        int    		width, height;
	unsigned char	*ptr, *data;
	unsigned short	*sptr;
	int		format = 0;
	void		*htable = NULL;
	Palette		*map = PaletteFind(w, cmap);
	Boolean		is8;
	unsigned long	lbt;

	GetPixmapWHD(dpy, pix, &width, &height, NULL);
	xim = XGetImage(dpy, pix, 0, 0, width, height, AllPlanes, ZPixmap);

	if (map == NULL)
		map = PaletteGetDefault(w);

	if (map->isMapped) {
		unsigned char	*cptr;

		image = ImageNewCmap(width, height, map->ncolors);
		cptr = image->cmapData;

		for (y = 0; y < map->ncolors; y++, cptr += 3) {
			XColor	*col = PaletteLookup(map, y);
			unsigned char	r = col->red >> 8;
			unsigned char	g = col->green >> 8;
			unsigned char	b = col->blue >> 8;

			cptr[0] = r;
			cptr[1] = g;
			cptr[2] = b;
		}
	} else {
		image = ImageNew(width, height);
	}

	ptr   = image->data;
	sptr  = (unsigned short *)image->data;
	data  = xim->data;
	lbt   = low_bits_table[xim->depth];

	for (y = 0; y < height; y++) {
		for (x = 0; x < width; x++) {
			XColor		c, *col;
			Pixel		pixel;
			unsigned char	r, g, b;

			if (xim->bits_per_pixel == 8) 
				pixel = data[ZINDEX8(x, y, xim)] & lbt;
			else
				pixel = XGetPixel(xim, x, y);

			if (map->isMapped) {
				if (map->ncolors <= 256)
					*ptr++  = pixel;
				else
					*sptr++ = pixel;
				
				r = image->cmapData[pixel*3+0];
				g = image->cmapData[pixel*3+1];
				b = image->cmapData[pixel*3+2];
			} else {
				col = PaletteLookup(map, pixel);

				*ptr++ = r = col->red >> 8;
				*ptr++ = g = col->green >> 8;
				*ptr++ = b = col->blue >> 8;
			}

			if (r != g || g != b)
				format = 2;
			else if (format == 0 && r != 0 && r != 255)
				format = 1;
		}

		if (y % 64 == 0)
			StateTimeStep();
	}

	/*
	**  Check to see if we just created a B&W or Grey scale image?
	*/
	if (format == 0 || format == 1) {
		int		newSize;
		unsigned char	*newMap;
		unsigned char	*ip;
		int		inc, v;

		if (format == 0) {
			newSize = 2;
			newMap = (unsigned char *)XtCalloc(sizeof(char) * 3, 2);
			newMap[0+0] = 0;
			newMap[0+1] = 0;
			newMap[0+2] = 0;
			newMap[3+0] = 255;
			newMap[3+1] = 255;
			newMap[3+2] = 255;
		} else {
			newSize = 256;
			newMap = (unsigned char *)XtCalloc(sizeof(char) * 3, 256);
			for (y = 0; y < 256; y++) {
				newMap[y * 3 + 0] = y;
				newMap[y * 3 + 1] = y;
				newMap[y * 3 + 2] = y;
			}
		}

		ip = image->data;
		for (y = 0; y < height; y++) {
			for (x = 0; x < width; x++, ip++) {
				unsigned char	*rgb;

				rgb = ImagePixel(image, x, y);

				if (format == 0 && *rgb == 255) {
					*ip = 1;
				} else {
					*ip = *rgb;
				}
			}
		}

		if (image->cmapData != NULL)
			XtFree((XtPointer)image->cmapData);

		image->cmapSize = newSize;
		image->cmapData = newMap;

		if (format == 0)
			image->isBW = True;
		else if (format == 1)
			image->isGrey = True;
	}

	image->sourceColormap = (unsigned long)cmap;
	image->sourcePixmap   = (unsigned long)pix;

	if (htable != NULL)
		HashDestroy(htable);
	XDestroyImage(xim);

	return image;
}

void PixmapToImageMask(Widget w, Image *image, Pixmap mask)
{
	XImage		*xim;
	int		width, height;
	int		x, y, endX, endY;
	unsigned char	*ip;
	Display		*dpy = XtDisplay(w);

	image->sourceMask = mask;
	GetPixmapWHD(dpy, mask, &width, &height, NULL);
	xim = XGetImage(dpy, mask, 0, 0, width, height, AllPlanes, ZPixmap);

	ImageMakeMask(image);
	ip = image->maskData;

	if ((endX = image->width) > width)
		endX = width;
	if ((endY = image->height) > height)
		endY = height;

	for (y = 0; y < endY; y++) {
		for (x = 0; x < endX; x++) 
			*ip++ = (Boolean)XGetPixel(xim, x, y);
		for (;x < image->width; x++) 
			*ip++ = True;
	}
	XDestroyImage(xim);
}

/*
**  Compress an image into a nice number of
**   colors for display purposes.
*/
static Image *quantizeColormap(Image *input, Palette *map, Boolean flag)
{
	Image		*output;
	unsigned char	*op;
	int		x, y;
	int		ncol;

	/*
	**  If the output is either B&W or grey do something
	**   fast an easy.
	*/
	if (!map->isGrey) 
		return ImageCompress(input, map->ncolors);
	
	ncol = map->ncolors > 256 ? 256 : map->ncolors;
	output = ImageNewCmap(input->width, input->height, ncol); 

	op = output->data;

	for (y = 0; y < ncol; y++) {
		unsigned char	v = ((float)y / (float)(ncol-1)) * 255.0;
		ImageSetCmap(output, y, v, v, v);
	}

	for (y = 0; y < input->height; y++) {
		for (x = 0; x < input->width; x++, op++) {
			unsigned char	*dp, v;

			dp = ImagePixel(input, x, y);
			v = (dp[0]*11 + dp[1]*16 + dp[2]*5) >> 5;  /* pp=.33R+.5G+.17B */
			*op = (int)(((float)v / 256.0) * (float)ncol);
		}
	}

	output->maskData = input->maskData;
	input->maskData  = NULL;
	ImageDelete(input);
	return output;
}

static void compressColormap(Image *image)
{
	unsigned char	used[32768];
	int		size = image->width * image->height;
	int		i, count, newSize;
	unsigned char	*newMap;
	unsigned short	*isp;
	unsigned char	*icp;

	if (image->cmapSize <= 2 || image->cmapPacked)
		return;

	memset(used, False, sizeof(used));
	
	/*
	**  Find out usage information over the colormap 
	*/
	count = 0;
	if (image->cmapSize > 256) {
		isp = (unsigned short *)image->data;
		for (i = 0; i < size && count != image->cmapSize; i++, isp++) {
			if (!used[*isp]) {
				used[*isp] = True;
				count++;
			}
		}
	} else {
		icp = image->data;
		for (i = 0; i < size && count != image->cmapSize; i++, icp++) {
			if (!used[*icp]) {
				used[*icp] = True;
				count++;
			}
		}
	}

	/*
	**  Colormap is fully used.
	*/
	if (count == image->cmapSize) {
		image->cmapPacked = True;
		return;
	}

	/*
	**  Now build the remapping colormap, and
	**    set the index.
	*/
	newSize = count;
	newMap = (unsigned char *)XtCalloc(count, sizeof(unsigned char) * 3);
	for (count = i = 0; i < image->cmapSize; i++) {
		if (!used[i])
			continue;
		newMap[count * 3 + 0] = image->cmapData[i * 3 + 0];
		newMap[count * 3 + 1] = image->cmapData[i * 3 + 1];
		newMap[count * 3 + 2] = image->cmapData[i * 3 + 2];
		used[i] = count++;
	}

	if (image->cmapSize > 256 && newSize > 256) {
		isp = (unsigned short *)image->data;
		for (i = 0; i < size; i++, isp++)
			*isp = used[*isp];
	} else if (image->cmapSize > 256 && newSize <= 256) {
		/*
		**  Map a big colormap down to a small one.
		*/
		isp = (unsigned short *)image->data;
		icp = image->data;
		for (i = 0; i < size; i++, icp++, isp++)
			*icp = used[*isp];

		image->data = (unsigned char *)XtRealloc((XtPointer)image->data, size * sizeof(unsigned char));
	} else {
		icp = image->data;
		for (i = 0; i < size; i++, icp++)
			*icp = used[*icp];
	}

	XtFree((XtPointer)image->cmapData);
	image->cmapData = newMap;
	image->cmapSize = newSize;
	image->cmapPacked = True;
	image->isGrey = False;
}

/*
**  Convert an imput image into a nice pixmap 
**   so we can edit it.
**
**  Side effect  -- always destroy the input image
*/
Boolean ImageToPixmap(Image *image, Widget w, Pixmap *pix, Colormap *cmap)
{
	GC		gc;
	Display		*dpy = XtDisplay(w);
	Palette         *map;
	XImage		*xim;
	int		x, y;
	int		width = image->width, height = image->height;

	map   = PaletteCreate(w);
	*cmap = map->cmap;

        if ((*pix = XCreatePixmap(dpy, DefaultRootWindow(dpy), image->width, image->height, map->depth)) == None)
		return False;

	if ((xim = NewXImage(dpy, NULL, map->depth, image->width, image->height)) == NULL) {
		XFreePixmap(dpy, *pix);
		return False;
	}

	if ((image->cmapSize > map->ncolors) ||
	    (image->cmapSize == 0 && map->isMapped))
		image = quantizeColormap(image, map, False);

	if (image->cmapSize > 0)
		compressColormap(image);

	imageToPixmapLoop(dpy, image, map, xim, pix);

	return True;
}

Pixmap	MaskDataToPixmap(Widget w, int width, int height, 
				char *data, XRectangle *rect)
{
	Display		*dpy = XtDisplay(w);
	GC		gc;
	Pixmap		mask;
	XImage		*xim;
	int		x, y;
	int		xs, ys;
	unsigned char	*ucp;
	int		pWidth, pHeight;

	if (data == NULL)
		return None;

	if (rect == NULL) {
		xs = 0;
		ys = 0;
		pWidth  = width;
		pHeight = height;
	} else {
		xs = rect->x;
		ys = rect->y;
		pWidth  = rect->width;
		pHeight = rect->height;
	}

	mask = XCreatePixmap(dpy, DefaultRootWindow(dpy), pWidth, pHeight, 1);
	gc   = XCreateGC(dpy, mask, 0, 0);
	xim  = NewXImage(dpy, NULL, 1, pWidth, pHeight);

	if (xim->byte_order != xim->bitmap_bit_order) {
		for (y = 0; y < pHeight; y++) {
			ucp = data + (width * (y + ys)) + xs;
			for (x = 0; x < pWidth; x++, ucp++)
				XPutPixel(xim, x, y, *ucp);
		}
	} else {
		unsigned char	*op = xim->data;
		unsigned char	*cp;

		if (xim->bitmap_bit_order == MSBFirst) {
			for (y = 0; y < pHeight; y++) {
				ucp = data + (width * (y + ys)) + xs;
				for (x = 0; x < pWidth; x++, ucp++) {
					unsigned char	v = 0x80 >> (x & 7);

					cp = &op[ZINDEX1(x, y, xim)];
					if (*ucp)
						*cp |= v;
					else
						*cp &= ~v;
				}
			}
		} else {
			for (y = 0; y < pHeight; y++) {
				ucp = data + (width * (y + ys)) + xs;
				for (x = 0; x < pWidth; x++, ucp++) {
					unsigned char	v = 0x01 << (x & 7);

					cp = &op[ZINDEX1(x, y, xim)];
					if (*ucp)
						*cp |= v;
					else
						*cp &= ~v;
				}
			}
		}
		
	}

	XPutImage(dpy, mask, gc, xim, 0, 0, 0, 0, pWidth, pHeight);
	XFreeGC(dpy, gc);

	XDestroyImage(xim);

	return mask;
}

Pixmap	ImageMaskToPixmap(Widget w, Image *image)
{
	return MaskDataToPixmap(w, image->width,
				image->height, image->maskData, NULL);
}

/*
**  Convert an imput image into a nice pixmap 
**   so we can edit it.
**
**  Side effect  -- always destroy the input image
*/
static void imageToPixmapLoop(Display *dpy, Image *image, Palette *map, XImage *xim, Pixmap *pix)
{
	GC		gc;
	int		x, y;
	int		width = image->width, height = image->height;

	if (image->cmapSize > 0) {
		unsigned short 	*sdp = (unsigned short *)image->data;
		unsigned char 	*cdp = (unsigned char  *)image->data;
		Pixel		*list = (Pixel*)XtCalloc(sizeof(Pixel), image->cmapSize);
		XColor		*xcol = (XColor*)XtCalloc(sizeof(XColor), image->cmapSize);

		for (y = 0; y < image->cmapSize; y++) {
			xcol[y].red   = image->cmapData[y * 3 + 0] << 8;
			xcol[y].green = image->cmapData[y * 3 + 1] << 8;
			xcol[y].blue  = image->cmapData[y * 3 + 2] << 8;
		}

		PaletteAllocN(map, xcol, image->cmapSize, list);

		if (xim->bits_per_pixel == 8) {
			unsigned char	*data = xim->data;

			for (y = 0; y < height; y++)
				for (x = 0; x < width; x++, sdp++, cdp++) 
					data[ZINDEX8(x, y, xim)] = list[image->cmapSize > 256 ? *sdp : *cdp];
		} else {
			/*
			**  Slow loop
			*/
			for (y = 0; y < height; y++) {
				for (x = 0; x < width; x++, sdp++, cdp++) 
					XPutPixel(xim, x, y, list[image->cmapSize > 256 ? *sdp : *cdp]);
				if (y % 256 == 0)
					StateTimeStep();
			}
		}
		
		XtFree((XtPointer)list);
		XtFree((XtPointer)xcol);
	} else {
		int		step = 64 * 256 / width;
		unsigned char	*cp = image->data;

		for (y = 0; y < height; y++) {
			for (x = 0; x < width; x++) {
				XColor	c;
				Pixel	p;

				c.red   = *cp++ << 8;
				c.green = *cp++ << 8;
				c.blue  = *cp++ << 8;

				p = PaletteAlloc(map, &c);

				if (xim->bits_per_pixel == 8)
					xim->data[ZINDEX8(x, y, xim)] = p;
				else
					XPutPixel(xim, x, y, p);
			}

			if (y % step == 0)
				StateTimeStep();
		}
	}

	gc = XCreateGC(dpy, *pix, 0, 0);
	XPutImage(dpy, *pix, gc, xim, 0, 0, 0, 0, width, height);
	XFreeGC(dpy, gc);

	XDestroyImage(xim);

	ImageDelete(image);
}

Boolean ImageToPixmapCmap(Image *image, Widget w, Pixmap *pix, Colormap cmap)
{
	GC		gc;
	Display		*dpy = XtDisplay(w);
	Palette         *map;
	XImage		*xim;
	int		x, y;
	int		width = image->width, height = image->height;

	if ((map = PaletteFind(w, cmap)) == NULL)
		map = PaletteGetDefault(w);

	if (*pix == None) {
		if ((*pix = XCreatePixmap(dpy, RootWindowOfScreen(XtScreen(w)), image->width, image->height, map->depth)) == None)
			return False;
	}

	if ((xim = NewXImage(dpy, NULL, map->depth, image->width, image->height)) == NULL) {
		XFreePixmap(dpy, *pix);
		return False;
	}

	if ((image->cmapSize > map->ncolors) ||
	    (image->cmapSize == 0 && map->isMapped))
		image = quantizeColormap(image, map, False);

	if (image->cmapSize > 0)
		compressColormap(image);

	imageToPixmapLoop(dpy, image, map, xim, pix);

	return True;
}