/* Copyright (C) 1995, 1996 Aladdin Enterprises.  All rights reserved.
  
  This file is part of Aladdin Ghostscript.
  
  Aladdin Ghostscript is distributed with NO WARRANTY OF ANY KIND.  No author
  or distributor accepts any responsibility for the consequences of using it,
  or for whether it serves any particular purpose or works at all, unless he
  or she says so in writing.  Refer to the Aladdin Ghostscript Free Public
  License (the "License") for full details.
  
  Every copy of Aladdin Ghostscript must include a copy of the License,
  normally in a plain ASCII text file named PUBLIC.  The License grants you
  the right to copy, modify and redistribute Aladdin Ghostscript, but only
  under certain conditions described in the License.  Among other things, the
  License requires that the copyright notice and this notice be preserved on
  all copies.
*/

/* gximage0.c */
/* Generic image enumeration and cleanup */
#include "gx.h"
#include "memory_.h"
#include "gserrors.h"
#include "gxdevice.h"
#include "gxcpath.h"
#include "gximage.h"

/* Process the next piece of an image */
int
gx_default_image_data(gx_device *dev,
  void *info, const byte **planes, uint raster,
  int x, int y, int dwidth, int dheight)
{	gx_image_enum *penum = info;
	int x_end = x + dwidth;
	int y_end = y + dheight;
	uint rsize = penum->bytes_per_row;
	uint pos = penum->byte_in_row;
	int width = penum->width;
	int nplanes = penum->num_planes;
	uint bcount =			/* bytes per data row */
	  (dwidth * penum->bps * (penum->spp / penum->num_planes) + 7) >> 3;
	uint dpos = 0;
	fixed adjust = penum->adjust;
	int code;

	if ( dwidth == 0 || dheight == 0 )
	  return 0;
	if ( penum->x != x || penum->y != y )
	  return_error(gs_error_rangecheck);
	if ( x_end < width )
	  --y_end;
	else
	  x_end = 0;

	/* We've accumulated an entire set of planes. */
	/* Set up the clipping and/or RasterOp device if needed. */

	if ( penum->clip_dev )
	   {	gx_device_clip *cdev = penum->clip_dev;
		cdev->target = dev;
		dev = (gx_device *)cdev;
	   }
	if ( penum->rop_dev )
	  {	gx_device_rop_texture *rtdev = penum->rop_dev;
		((gx_device_forward *)rtdev)->target = dev;
		dev = (gx_device *)rtdev;
	  }

	/* Now render complete rows. */

	while ( penum->x != x_end || penum->y < y_end )
	   {	/* Fill up a row, then display it. */
		int px;

		for ( px = 0; px < nplanes; px++ )
		  (*penum->unpack)(penum->buffer + (px << penum->log2_xbytes),
				   planes[px] + dpos, bcount,
				   &penum->map[px], penum->spread, pos);
		pos += bcount;
		dpos += bcount;
		if ( pos == rsize )	/* filled an entire row */
		  {
#ifdef DEBUG
			if ( gs_debug_c('B') )
			  { int i, n = width * penum->spp;
			    dputs("[B]row:");
			    for ( i = 0; i < n; i++ )
			      dprintf1(" %02x", penum->buffer[i]);
			    dputs("\n");
			  }
#endif
			penum->xcur = dda_current(penum->next_x);
			dda_next(penum->next_x);
			penum->ycur = dda_current(penum->next_y);
			dda_next(penum->next_y);
			if ( !penum->interpolate )
			  switch ( penum->posture )
			  {
			  case image_portrait:
			    {	/* Precompute integer y and height, */
				/* and check for clipping. */
				fixed yc = penum->ycur,
				  yn = dda_current(penum->next_y);

				if ( yn < yc )
				  { fixed temp = yn; yn = yc; yc = temp; }
				yc -= adjust;
				if ( yc >= penum->clip_outer.q.y ) goto mt;
				yn += adjust;
				if ( yn <= penum->clip_outer.p.y ) goto mt;
				penum->yci = fixed2int_pixround(yc);
				penum->hci =
				  fixed2int_pixround(yn) - penum->yci;
				if ( penum->hci == 0 ) goto mt;
			    }	break;
			  case image_landscape:
			    {	/* Check for no pixel centers in x. */
				fixed xc = penum->xcur,
				  xn = dda_current(penum->next_x);

				xc -= adjust;
				if ( xn < xc )
				  { fixed temp = xn; xn = xc; xc = temp; }
				if ( xc >= penum->clip_outer.q.x ) goto mt;
				xn += adjust;
				if ( xn <= penum->clip_outer.p.x ) goto mt;
				penum->xci = fixed2int_pixround(xc);
				penum->wci =
				  fixed2int_pixround(xn) - penum->xci;
				if ( penum->wci == 0 ) goto mt;
			    }	break;
			  case image_skewed:
			    ;
			  }
			code = (*penum->render)(penum, penum->buffer,
						width * penum->spp, 1, dev);
			if ( code < 0 )
			  goto err;
mt:			penum->x = 0;
			if ( ++(penum->y) == penum->height )
			  goto end;
			pos = 0;
		   }
		else
		  penum->x = x_end;
	   }
	penum->byte_in_row = pos;
	code = 0;
	goto out;
end:	/* End of data.  Render any left-over buffered data. */
	switch ( penum->posture )
	  {
	  case image_portrait:
	    {	fixed yc = dda_current(penum->next_y);
		penum->yci = fixed2int_rounded(yc - adjust);
		penum->hci = fixed2int_rounded(yc + adjust) - penum->yci;
	    }	break;
	  case image_landscape:
	    {	fixed xc = dda_current(penum->next_x);
		penum->xci = fixed2int_rounded(xc - adjust);
		penum->wci = fixed2int_rounded(xc + adjust) - penum->xci;
	    }	break;
	  case image_skewed:		/* pacify compilers */
	    ;
	  }
	code = (*penum->render)(penum, NULL, width * penum->spp, 0, dev);
	if ( code < 0 )
	  { penum->y--;
	    goto err;
	  }
	code = 1;
	goto out;
err:	/* Error or interrupt, restore original state. */
	penum->x = x;
	while ( penum->y > y )
	  { dda_previous(penum->next_x);
	    dda_previous(penum->next_y);
	    --(penum->y);
	  }
	/* Note that caller must call end_image */
	/* for both error and normal termination. */
out:	return code;
}

/* Clean up by releasing the buffers. */
/* Currently we ignore draw_last. */
int
gx_default_end_image(gx_device *dev, void *info, bool draw_last)
{	gx_image_enum *penum = info;
	gs_memory_t *mem = penum->memory;
	stream_IScale_state *scaler = penum->scaler;

	gs_free_object(mem, penum->rop_dev, "image RasterOp");
	gs_free_object(mem, penum->clip_dev, "image clipper");
	if ( scaler != 0 )
	  { (*s_IScale_template.release)((stream_state *)scaler);
	    gs_free_object(mem, scaler, "image scaler state");
	  }
	gs_free_object(mem, penum->line, "image line");
	gs_free_object(mem, penum->buffer, "image buffer");
	gs_free_object(mem, penum, "gx_default_end_image");
	return 0;
}

/* ------ Unpacking procedures ------ */

void
image_unpack_copy(byte *bptr, const byte *data, uint dsize,
  const sample_map *pmap, int spread, uint inpos)
{	register byte *bufp = bptr + inpos;
	if ( data != bufp )
	  memcpy(bufp, data, dsize);
}

void
image_unpack_1(byte *bptr, register const byte *data, uint dsize,
  const sample_map *pmap, int spread, uint inpos)
{	register bits32 *bufp = (bits32 *)(bptr + (inpos << 3));
	int left = dsize;
	register const bits32 *map = &pmap->table.lookup4x1to32[0];
	register uint b;
	if ( left & 1 )
	   {	b = data[0];
		bufp[0] = map[b >> 4];
		bufp[1] = map[b & 0xf];
		data++, bufp += 2;
	   }
	left >>= 1;
	while ( left-- )
	   {	b = data[0];
		bufp[0] = map[b >> 4];
		bufp[1] = map[b & 0xf];
		b = data[1];
		bufp[2] = map[b >> 4];
		bufp[3] = map[b & 0xf];
		data += 2, bufp += 4;
	   }
}

void
image_unpack_2(byte *bptr, register const byte *data, uint dsize,
  const sample_map *pmap, int spread, uint inpos)
{	register bits16 *bufp = (bits16 *)(bptr + (inpos << 2));
	int left = dsize;
	register const bits16 *map = &pmap->table.lookup2x2to16[0];
	while ( left-- )
	   {	register unsigned b = *data++;
		*bufp++ = map[b >> 4];
		*bufp++ = map[b & 0xf];
	   }
}

void
image_unpack_4(byte *bptr, register const byte *data, uint dsize,
  const sample_map *pmap, register int spread, uint inpos)
{	register byte *bufp = bptr + (inpos << 1) * spread;
	int left = dsize;
	register const byte *map = &pmap->table.lookup8[0];
	while ( left-- )
	   {	register unsigned b = *data++;
		*bufp = map[b >> 4]; bufp += spread;
		*bufp = map[b & 0xf]; bufp += spread;
	   }
}

void
image_unpack_8(byte *bptr, const byte *data, uint dsize,
  const sample_map *pmap, int spread, uint inpos)
{	register byte *bufp = bptr + inpos;
	if ( pmap->table.lookup8[0] != 0 || pmap->table.lookup8[255] != 255 )
	  {	register uint left = dsize;
		register const byte *map = &pmap->table.lookup8[0];
		while ( left-- )
		  *bufp++ = map[*data++];
	  }
	else if ( data != bufp )
	  memcpy(bufp, data, dsize);
}