/* Copyright (C) 1992, 1993, 1994 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.
*/

/* zht2.c */
/* Level 2 sethalftone operator */
#include "ghost.h"
#include "errors.h"
#include "oper.h"
#include "gsstruct.h"
#include "gxdevice.h"		/* for gzht.h */
#include "gzht.h"
#include "estack.h"
#include "ialloc.h"
#include "idict.h"
#include "idparam.h"
#include "igstate.h"
#include "icolor.h"
#include "store.h"

/* Imported from zht.c */
int zscreen_enum_init(P6(os_ptr, const gx_ht_order *, gs_screen_halftone *,
			 ref *, int, int (*)(P1(os_ptr))));

/* Forward references */
private int dict_spot_params(P4(const ref *, gs_spot_halftone *,
  ref *, ref *));
private int dict_spot_results(P2(ref *, const gs_spot_halftone *));
private int dict_threshold_params(P3(const ref *,
  gs_threshold_halftone *, ref *));

/* Structure types */
private_st_halftone_component();
gs_private_st_element(st_halftone_component_element, gs_halftone_component,
  "gs_halftone_component[]", ht_comp_elt_enum_ptrs, ht_comp_elt_reloc_ptrs,
  st_halftone_component);

/* GC procedures */

#define hptr ((gs_halftone_component *)vptr)

private ENUM_PTRS_BEGIN(halftone_component_enum_ptrs) return 0;
	case 0:
		if ( hptr->type != ht_type_threshold )
		  return 0;
		*pep = (void *)hptr->params.threshold.thresholds; /* discard const */
		break;
ENUM_PTRS_END

private RELOC_PTRS_BEGIN(halftone_component_reloc_ptrs) {
	if ( hptr->type == ht_type_threshold )
	  RELOC_PTR(gs_halftone_component, params.threshold.thresholds);
} RELOC_PTRS_END

#undef hptr

/* <dict> <dict5> .sethalftone5 - */
float spot_dummy(P2(floatp, floatp));		/* in zht1.c */
int spot_sample_finish(P1(os_ptr));		/* in zht.c */
private int sethalftone_finish(P1(os_ptr));
private int sethalftone_cleanup(P1(os_ptr));
private int
zsethalftone5(register os_ptr op)
{	uint count;
	gs_halftone_component *phtc;
	gs_halftone_component *pc;
	int code = 0;
	int i, j;
	gs_halftone *pht;
	gx_device_halftone *pdht;
	static const char _ds *color_names[] =
	 { gs_ht_separation_name_strings };
	ref sprocs[countof(color_names)];
	ref tprocs[countof(color_names)];
	int npop = 2;

	check_dict_read(*op);
	count = 0;
	for ( i = 0; i < countof(color_names); i++ )
	{	ref *pvalue;
		if ( dict_find_string(op, color_names[i], &pvalue) > 0 )
			count++;
		else if ( i == gs_ht_separation_Default )
			return_error(e_typecheck);
	}
	check_estack(5);		/* for sampling Type 1 screens */
	refset_null(sprocs, countof(sprocs));
	refset_null(tprocs, countof(tprocs));
	pht = ialloc_struct(gs_halftone, &st_halftone, ".sethalftone5");
	phtc = ialloc_struct_array(count, gs_halftone_component,
				   &st_halftone_component_element,
				   ".sethalftone5");
	pdht = ialloc_struct(gx_device_halftone, &st_device_halftone,
			     ".sethalftone5");
	if ( pht == 0 || phtc == 0 || pdht == 0 )
	  code = gs_note_error(e_VMerror);
	else
	  for ( i = 0, j = 0, pc = phtc; i < countof(color_names); i++ )
	{	int type;
		ref *pvalue;
		if ( dict_find_string(op, color_names[i], &pvalue) > 0 )
		{	check_dict_read(*pvalue);
			if ( dict_int_param(pvalue, "HalftoneType", 1, 5, 0,
					    &type) < 0
			   )
			  {	code = gs_note_error(e_typecheck);
				break;
			  }
			switch ( type )
			{
			default:
				code = gs_note_error(e_rangecheck);
				break;
			case 1:
				code = dict_spot_params(pvalue,
					&pc->params.spot, sprocs + j,
					tprocs + j);
				pc->params.spot.screen.spot_function =
					spot_dummy;
				pc->type = ht_type_spot;
				break;
			case 3:
				code = dict_threshold_params(pvalue,
					&pc->params.threshold, tprocs + j);
				pc->type = ht_type_threshold;
				break;
			}
			if ( code < 0 )
				break;
			pc->cname = i;
			pc++, j++;
		}
	}
	if ( code >= 0 )
	  {	pht->type = ht_type_multiple;
		pht->params.multiple.components = phtc;
		pht->params.multiple.num_comp = count;
		code = gs_sethalftone_prepare(igs, pht, pdht);
	  }
	if ( code >= 0 )
	  for ( j = 0, pc = phtc; j < count; j++, pc++ )
	{	if ( pc->type == ht_type_spot )
		{	ref *pvalue;
			dict_find_string(op, color_names[pc->cname], &pvalue);
			code = dict_spot_results(pvalue, &pc->params.spot);
			if ( code < 0 )
				break;
		}
	}
	if ( code >= 0 )
	  {	/* Schedule the sampling of any Type 1 screens, */
		/* and any (Type 1 or Type 3) TransferFunctions. */
		/* Save the stack depths in case we have to back out. */
		uint edepth = ref_stack_count(&e_stack);
		uint odepth = ref_stack_count(&o_stack);
		ref odict, odict5;

		odict = op[-1];
		odict5 = *op;
		pop(2);  op = osp;
		esp += 5;
		make_mark_estack(esp - 4, es_other, sethalftone_cleanup);
		esp[-3] = op[-1];		/* halftone dict */
		make_istruct(esp - 2, 0, pht);
		make_istruct(esp - 1, 0, pdht);
		make_op_estack(esp, sethalftone_finish);
		for ( j = 0; j < count; j++ )
		  {	gx_ht_order *porder =
			  (pdht->components == 0 ? &pdht->order :
			   &pdht->components[j].corder);
			switch ( phtc[j].type )
			  {
			  case ht_type_spot:
				code = zscreen_enum_init(op, porder,
					&phtc[j].params.spot.screen,
					&sprocs[j], 0, 0);
				if ( code < 0 )
					break;
				/* falls through */
			  case ht_type_threshold:
				if ( !r_has_type(tprocs + j, t__invalid) )
				{	/* Schedule TransferFunction sampling. */
					/****** check_xstack IS WRONG ******/
					check_ostack(zcolor_remap_one_ostack);
					check_estack(zcolor_remap_one_estack);
					code = zcolor_remap_one(tprocs + j,
						op, porder->transfer, igs,
						zcolor_remap_one_finish);
					op = osp;
				}
				break;
			  }
			if ( code < 0 )
			  {	/* Restore the stack. */
				ref_stack_pop_to(&o_stack, odepth);
				ref_stack_pop_to(&e_stack, edepth);
				op = osp;
				op[-1] = odict;
				*op = odict5;
				break;
			  }
			npop = 0;
		  }
	  }
	if ( code < 0 )
	  {	ifree_object(pdht, ".sethalftone5");
		ifree_object(phtc, ".sethalftone5");
		ifree_object(pht, ".sethalftone5");
		return code;
	  }
	pop(npop);
	return o_push_estack;
}
/* Install the halftone after sampling. */
private int
sethalftone_finish(os_ptr op)
{	gx_device_halftone *pdht = r_ptr(esp, gx_device_halftone);
	int code;
	if ( pdht->components )
		pdht->order = pdht->components[0].corder;
	code = gx_ht_install(igs, r_ptr(esp - 1, gs_halftone), pdht);
	if ( code < 0 )
		return code;
	istate->halftone = esp[-2];
	esp -= 4;
	sethalftone_cleanup(op);
	return o_pop_estack;
}
/* Clean up after installing the halftone. */
private int
sethalftone_cleanup(os_ptr op)
{	ifree_object(esp[4].value.pstruct,
		     "sethalftone_cleanup(device halftone)");
	ifree_object(esp[3].value.pstruct,
		     "sethalftone_cleanup(halftone)");
	return 0;
}

/* ------ Initialization procedure ------ */

op_def zht2_l2_op_defs[] = {
		op_def_begin_level2(),
	{"2.sethalftone5", zsethalftone5},
		/* Internal operators */
	{"0%sethalftone_finish", sethalftone_finish},
	op_def_end(0)
};

/* ------ Internal routines ------ */

/* Extract frequency, angle, spot function, and accurate screens flag */
/* from a dictionary. */
private int
dict_spot_params(const ref *pdict, gs_spot_halftone *psp,
  ref *psproc, ref *ptproc)
{	int code;
	check_dict_read(*pdict);
	if ( (code = dict_float_param(pdict, "Frequency", 0.0,
				      &psp->screen.frequency)) != 0 ||
	     (code = dict_float_param(pdict, "Angle", 0.0,
				      &psp->screen.angle)) != 0 ||
	     (code = dict_proc_param(pdict, "SpotFunction", psproc, false)) != 0 ||
	     (code = dict_bool_param(pdict, "AccurateScreens", false,
				     &psp->accurate_screens)) < 0 ||
	     (code = dict_proc_param(pdict, "TransferFunction", ptproc, false)) < 0
	   )
		return (code < 0 ? code : e_undefined);
	psp->transfer = (code > 0 ? (gs_mapping_proc)0 : gs_mapped_transfer);
	return 0;
}

/* Set actual frequency and angle in a dictionary. */
private int
dict_real_result(ref *pdict, const char _ds *kstr, floatp val)
{	int code = 0;
	ref *discard;
	if ( dict_find_string(pdict, kstr, &discard) > 0 )
	{	ref rval;
		check_dict_write(*pdict);
		make_real(&rval, val);
		code = dict_put_string(pdict, kstr, &rval);
	}
	return code;
}
private int
dict_spot_results(ref *pdict, const gs_spot_halftone *psp)
{	int code;
	code = dict_real_result(pdict, "ActualFrequency",
				psp->screen.actual_frequency);
	if ( code < 0 )
		return code;
	return dict_real_result(pdict, "ActualAngle",
				psp->screen.actual_angle);
}

/* Extract width, height, and thresholds from a dictionary. */
private int
dict_threshold_params(const ref *pdict, gs_threshold_halftone *ptp,
  ref *ptproc)
{	int code;
	ref *tstring;
	check_dict_read(*pdict);
	if ( (code = dict_int_param(pdict, "Width", 1, 0x7fff, -1,
				    &ptp->width)) < 0 ||
	     (code = dict_int_param(pdict, "Height", 1, 0x7fff, -1,
				    &ptp->height)) < 0 ||
	     (code = dict_find_string(pdict, "Thresholds", &tstring)) <= 0 ||
	     (code = dict_proc_param(pdict, "TransferFunction", ptproc, false)) < 0
	   )
		return (code < 0 ? code : e_undefined);
	check_read_type(*tstring, t_string);
	if ( r_size(tstring) != (long)ptp->width * ptp->height )
		return_error(e_rangecheck);
	ptp->thresholds = tstring->value.const_bytes;
	ptp->transfer = (code > 0 ? (gs_mapping_proc)0 : gs_mapped_transfer);
	return 0;
}
