/* Copyright (C) 1989, 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.
  
*/

/* zpath1.c */
/* PostScript Level 1 additional path operators */
#include "memory_.h"
#include "ghost.h"
#include "oper.h"
#include "errors.h"
#include "estack.h"	/* for pathforall */
#include "ialloc.h"
#include "igstate.h"
#include "gsstruct.h"
#include "gspath.h"
#include "store.h"

/* Forward references */
private int near common_arc(P2(os_ptr,
  int (*)(P6(gs_state *, floatp, floatp, floatp, floatp, floatp))));
private int near common_arct(P2(os_ptr, float *));

/* <x> <y> <r> <ang1> <ang2> arc - */
int
zarc(os_ptr op)
{	return common_arc(op, gs_arc);
}

/* <x> <y> <r> <ang1> <ang2> arcn - */
int
zarcn(os_ptr op)
{	return common_arc(op, gs_arcn);
}

/* Common code for arc[n] */
private int near
common_arc(os_ptr op,
  int (*aproc)(P6(gs_state *, floatp, floatp, floatp, floatp, floatp)))
{	float xyra[5];			/* x, y, r, ang1, ang2 */
	int code;
	if ( (code = num_params(op, 5, xyra)) < 0 ) return code;
	code = (*aproc)(igs, xyra[0], xyra[1], xyra[2], xyra[3], xyra[4]);
	if ( code >= 0 ) pop(5);
	return code;
}

/* <x1> <y1> <x2> <y2> <r> arct - */
int
zarct(register os_ptr op)
{	int code = common_arct(op, (float *)0);
	if ( code < 0 ) return code;
	pop(5);
	return 0;
}

/* <x1> <y1> <x2> <y2> <r> arcto <xt1> <yt1> <xt2> <yt2> */
private int
zarcto(register os_ptr op)
{	float tanxy[4];			/* xt1, yt1, xt2, yt2 */
	int code = common_arct(op, tanxy);
	if ( code < 0 ) return code;
	make_real(op - 4, tanxy[0]);
	make_real(op - 3, tanxy[1]);
	make_real(op - 2, tanxy[2]);
	make_real(op - 1, tanxy[3]);
	pop(1);
	return 0;
}

/* Common code for arct[o] */
private int near
common_arct(os_ptr op, float *tanxy)
{	float args[5];			/* x1, y1, x2, y2, r */
	int code;
	if ( (code = num_params(op, 5, args)) < 0 ) return code;
	return gs_arcto(igs, args[0], args[1], args[2], args[3], args[4], tanxy);
}

/* - flattenpath - */
private int
zflattenpath(register os_ptr op)
{	return gs_flattenpath(igs);
}

/* - reversepath - */
private int
zreversepath(register os_ptr op)
{	return gs_reversepath(igs);
}

/* - strokepath - */
private int
zstrokepath(register os_ptr op)
{	return gs_strokepath(igs);
}

/* - clippath - */
private int
zclippath(register os_ptr op)
{	return gs_clippath(igs);
}

/* - pathbbox <llx> <lly> <urx> <ury> */
private int
zpathbbox(register os_ptr op)
{	gs_rect box;
	int code = gs_pathbbox(igs, &box);
	if ( code < 0 ) return code;
	push(4);
	make_real(op - 3, box.p.x);
	make_real(op - 2, box.p.y);
	make_real(op - 1, box.q.x);
	make_real(op, box.q.y);
	return 0;
}

/* <moveproc> <lineproc> <curveproc> <closeproc> pathforall - */
private int path_continue(P1(os_ptr));
private int path_cleanup(P1(os_ptr));
private int
zpathforall(register os_ptr op)
{	gs_path_enum *penum;
	int code;
	check_proc(op[-3]);
	check_proc(op[-2]);
	check_proc(op[-1]);
	check_proc(*op);
	check_estack(8);
	if ( (penum = gs_path_enum_alloc(imemory, "pathforall")) == 0 )
		return_error(e_VMerror);
	code = gs_path_enum_init(penum, igs);
	if ( code < 0 )
	{	ifree_object(penum, "path_cleanup");
		return code;
	}
	/* Push a mark, the four procedures, and the path enumerator, */
	/* and then call the continuation procedure. */
	push_mark_estack(es_for, path_cleanup);	/* iterator */
	memcpy(esp + 1, op - 3, 4 * sizeof(ref));	/* 4 procs */
	esp += 5;
	make_istruct(esp, 0, penum);
	pop(4);  op -= 4;
	return path_continue(op);
}
/* Continuation procedure for pathforall */
private void pf_push(P3(gs_point *, int, os_ptr));
private int
path_continue(register os_ptr op)
{	gs_path_enum *penum = r_ptr(esp, gs_path_enum);
	gs_point ppts[3];
	int code;
	/* Make sure we have room on the o-stack for the worst case */
	/* before we enumerate the next path element. */
	check_ostack(6);	/* 3 points for curveto */
	code = gs_path_enum_next(penum, ppts);
	switch ( code )
	  {
	case 0:			/* all done */
	    { esp -= 6;
	      path_cleanup(op);
	      return o_pop_estack;
	    }
	default:		/* error */
	    return code;
	case gs_pe_moveto:
	    esp[2] = esp[-4];			/* moveto proc */
	    pf_push(ppts, 1, op);
	    break;
	case gs_pe_lineto:
	    esp[2] = esp[-3];			/* lineto proc */
	    pf_push(ppts, 1, op);
	    break;
	case gs_pe_curveto:
	    esp[2] = esp[-2];			/* curveto proc */
	    pf_push(ppts, 3, op);
	    break;
	case gs_pe_closepath:
	    esp[2] = esp[-1];			/* closepath proc */
	    break;
	  }
	push_op_estack(path_continue);
	++esp;		/* include pushed procedure */
	return o_push_estack;
}
/* Internal procedure to push one or more points */
private void
pf_push(gs_point *ppts, int n, os_ptr op)
{	while ( n-- )
	  { op += 2;
	    make_real(op - 1, ppts->x);
	    make_real(op, ppts->y);
	    ppts++;
	  }
	osp = op;
}
/* Clean up after a pathforall */
private int
path_cleanup(os_ptr op)
{	gs_path_enum *penum = r_ptr(esp + 6, gs_path_enum);
	gs_path_enum_cleanup(penum);
	ifree_object(penum, "path_cleanup");
	return 0;
}

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

BEGIN_OP_DEFS(zpath1_op_defs) {
	{"5arc", zarc},
	{"5arcn", zarcn},
	{"5arct", zarct},
	{"5arcto", zarcto},
	{"0clippath", zclippath},
	{"0flattenpath", zflattenpath},
	{"0pathbbox", zpathbbox},
	{"4pathforall", zpathforall},
	{"0reversepath", zreversepath},
	{"0strokepath", zstrokepath},
		/* Internal operators */
	{"0%path_continue", path_continue},
END_OP_DEFS(0) }