/* Copyright (C) 1992, 1995 Aladdin Enterprises.  All rights reserved.
  
  This file is part of GNU Ghostscript.
  
  GNU Ghostscript is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY.  No author or distributor accepts responsibility to
  anyone for the consequences of using it or for whether it serves any
  particular purpose or works at all, unless he says so in writing.  Refer
  to the GNU Ghostscript General Public License for full details.
  
*/

/* 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;
		ENUM_RETURN_CONST_STRING_PTR(gs_halftone_component, params.threshold.thresholds);
ENUM_PTRS_END

private RELOC_PTRS_BEGIN(halftone_component_reloc_ptrs) {
	if ( hptr->type == ht_type_threshold )
	  RELOC_CONST_STRING_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_type(*op, t_dictionary);
	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_type_only(*pvalue, t_dictionary);
			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] = odict;
		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;
			  default:	/* not possible here, but to keep */
					/* the compilers happy.... */
				;
			  }
			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 ------ */

BEGIN_OP_DEFS(zht2_l2_op_defs) {
		op_def_begin_level2(),
	{"2.sethalftone5", zsethalftone5},
		/* Internal operators */
	{"0%sethalftone_finish", sethalftone_finish},
END_OP_DEFS(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 *ignore;
	if ( dict_find_string(pdict, kstr, &ignore) > 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_only(*tstring, t_string);
	if ( r_size(tstring) != (long)ptp->width * ptp->height )
	  return_error(e_rangecheck);
	ptp->thresholds.data = tstring->value.const_bytes;
	ptp->thresholds.size = r_size(tstring);
	ptp->transfer = (code > 0 ? (gs_mapping_proc)0 : gs_mapped_transfer);
	return 0;
}