/* Copyright (C) 2001-2006 artofcode LLC.
   All Rights Reserved.
  
  This file is part of GNU ghostscript

  GNU ghostscript is free software; you can redistribute it and/or
  modify it under the terms of the version 2 of the GNU General Public
  License as published by the Free Software Foundation.

  GNU ghostscript is distributed in the hope that it will be useful, but WITHOUT
  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

  You should have received a copy of the GNU General Public License along with
  ghostscript; see the file COPYING. If not, write to the Free Software Foundation,
  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

*/

/* $Id: zcharout.c,v 1.8 2007/08/01 14:26:48 jemarch Exp $ */
/* Common code for outline (Type 1 / 4 / 42) fonts */
#include "memory_.h"
#include "ghost.h"
#include "oper.h"
#include "gscrypt1.h"
#include "gstext.h"
#include "gxdevice.h"		/* for gxfont.h */
#include "gxfont.h"
#include "gxfont1.h"
#include "dstack.h"		/* only for systemdict */
#include "estack.h"
#include "ichar.h"
#include "icharout.h"
#include "idict.h"
#include "ifont.h"
#include "igstate.h"
#include "iname.h"
#include "store.h"

/*
 * Execute an outline defined by a PostScript procedure.
 * The top elements of the stack are:
 *      <font> <code|name> <name> <outline_id>
 */
int
zchar_exec_char_proc(i_ctx_t *i_ctx_p)
{
    os_ptr op = osp;
	/*
	 * The definition is a PostScript procedure.  Execute
	 *      <code|name> proc
	 * within a systemdict begin/end and a font begin/end.
	 */
    es_ptr ep;

    check_estack(5);
    ep = esp += 5;
    make_op_estack(ep - 4, zend);
    make_op_estack(ep - 3, zend);
    ref_assign(ep - 2, op);
    make_op_estack(ep - 1, zbegin);
    make_op_estack(ep, zbegin);
    ref_assign(op - 1, systemdict);
    {
	ref rfont;

	ref_assign(&rfont, op - 3);
	ref_assign(op - 3, op - 2);
	ref_assign(op - 2, &rfont);
    }
    pop(1);
    return o_push_estack;
}

/*
 * Get the metrics for a character from the Metrics dictionary of a base
 * font.  If present, store the l.s.b. in psbw[0,1] and the width in
 * psbw[2,3].
 */
int				/*metrics_present*/
zchar_get_metrics(const gs_font_base * pbfont, const ref * pcnref,
		  double psbw[4])
{
    const ref *pfdict = &pfont_data(gs_font_parent(pbfont))->dict;
    ref *pmdict;

    if (dict_find_string(pfdict, "Metrics", &pmdict) > 0) {
	ref *pmvalue;

	check_type_only(*pmdict, t_dictionary);
	check_dict_read(*pmdict);
	if (dict_find(pmdict, pcnref, &pmvalue) > 0) {
	    if (num_params(pmvalue, 1, psbw + 2) >= 0) {	/* <wx> only */
		psbw[3] = 0;
		return metricsWidthOnly;
	    } else {
		int code;

		check_read_type_only(*pmvalue, t_array);
		switch (r_size(pmvalue)) {
		    case 2:	/* [<sbx> <wx>] */
			code = num_params(pmvalue->value.refs + 1,
					  2, psbw);
			psbw[2] = psbw[1];
			psbw[1] = psbw[3] = 0;
			break;
		    case 4:	/* [<sbx> <sby> <wx> <wy>] */
			code = num_params(pmvalue->value.refs + 3,
					  4, psbw);
			break;
		    default:
			return_error(e_rangecheck);
		}
		if (code < 0)
		    return code;
		return metricsSideBearingAndWidth;
	    }
	}
    }
    return metricsNone;
}

/* Get the vertical metrics for a character from Metrics2, if present. */
int
zchar_get_metrics2(const gs_font_base * pbfont, const ref * pcnref,
		   double pwv[4])
{
    const ref *pfdict = &pfont_data(gs_font_parent(pbfont))->dict;
    ref *pmdict;

    if (dict_find_string(pfdict, "Metrics2", &pmdict) > 0) {
	ref *pmvalue;

	check_type_only(*pmdict, t_dictionary);
	check_dict_read(*pmdict);
	if (dict_find(pmdict, pcnref, &pmvalue) > 0) {
	    check_read_type_only(*pmvalue, t_array);
	    if (r_size(pmvalue) == 4) {
		int code = num_params(pmvalue->value.refs + 3, 4, pwv);

		return (code < 0 ? code : metricsSideBearingAndWidth);
	    }
	}
    }
    return metricsNone;
}

/*
 * Get CDevProc.
 */
bool
zchar_get_CDevProc(const gs_font_base * pbfont, ref **ppcdevproc)
{
    const ref *pfdict = &pfont_data(gs_font_parent(pbfont))->dict;

    return dict_find_string(pfdict, "CDevProc", ppcdevproc) > 0;
}

/*
 * Consult Metrics2 and CDevProc, and call setcachedevice[2].  Return
 * o_push_estack if we had to call a CDevProc, or if we are skipping the
 * rendering process (only getting the metrics).
 * Returns exec_cont - a function, which must be called by caller after this function.
 */
int
zchar_set_cache(i_ctx_t *i_ctx_p, const gs_font_base * pbfont,
		const ref * pcnref, const double psb[2],
		const double pwidth[2], const gs_rect * pbbox,
		op_proc_t cont, op_proc_t *exec_cont,
		const double Metrics2_sbw_default[4])
{
    os_ptr op = osp;
    ref *pcdevproc;
    int have_cdevproc;
    ref rpop;
    bool metrics2;
    bool metrics2_use_default = false;
    double w2[10];
    gs_text_enum_t *penum = op_show_find(i_ctx_p);

    w2[0] = pwidth[0], w2[1] = pwidth[1];

    /* Adjust the bounding box for stroking if needed. */

    w2[2] = pbbox->p.x, w2[3] = pbbox->p.y;
    w2[4] = pbbox->q.x, w2[5] = pbbox->q.y;
    if (pbfont->PaintType != 0) {
	double expand = max(1.415, gs_currentmiterlimit(igs)) *
	gs_currentlinewidth(igs) / 2;

	w2[2] -= expand, w2[3] -= expand;
	w2[4] += expand, w2[5] += expand;
    }

    /* Check for Metrics2. */

    {
	int code = zchar_get_metrics2(pbfont, pcnref, w2 + 6);

	if (code < 0)
	    return code;
	metrics2 = code > 0;
    }

    /*
     * For FontType 9 and 11, if Metrics2 is missing, the caller provides
     * default Metrics2 values derived from the FontBBox.
     */
    if (!metrics2 && Metrics2_sbw_default != NULL) {
        w2[6] = Metrics2_sbw_default[2];
        w2[7] = Metrics2_sbw_default[3];
        w2[8] = Metrics2_sbw_default[0];
        w2[9] = Metrics2_sbw_default[1];
	metrics2 = true;
	metrics2_use_default = true;
    }

    /* Check for CDevProc or "short-circuiting". */

    have_cdevproc = zchar_get_CDevProc(pbfont, &pcdevproc);
    if (have_cdevproc || zchar_show_width_only(penum)) {
	int i;
	op_proc_t zsetc;
	int nparams;

	if (have_cdevproc) {
	    check_proc_only(*pcdevproc);
	    zsetc = zsetcachedevice2;
	    
	    /* If we have cdevproc and the font type is CID type 0,
	       we'll throw away Metrics2_sbw_default that is calculated 
	       from FontBBox. */
	    if (!metrics2 
		|| (penum->current_font->FontType == ft_CID_encrypted
		    && metrics2_use_default)) {
		w2[6] = w2[0], w2[7] = w2[1];
		w2[8] = w2[9] = 0;
	    }
	    nparams = 10;
	} else {
	    make_oper(&rpop, 0, zpop);
	    pcdevproc = &rpop;
	    if (metrics2)
		zsetc = zsetcachedevice2, nparams = 10;
	    else
		zsetc = zsetcachedevice, nparams = 6;
	}
	check_estack(3);
	/* Push the l.s.b. for .type1addpath if necessary. */
	if (psb != 0) {
	    push(nparams + 3);
	    make_real(op - (nparams + 2), psb[0]);
	    make_real(op - (nparams + 1), psb[1]);
	} else {
	    push(nparams + 1);
	}
	for (i = 0; i < nparams; ++i)
	    make_real(op - nparams + i, w2[i]);
	ref_assign(op, pcnref);
	push_op_estack(cont);
	push_op_estack(zsetc);
	++esp;
	ref_assign(esp, pcdevproc);
	return o_push_estack;
    } {
	int code =
	    (metrics2 ? gs_text_setcachedevice2(penum, w2) :
	     gs_text_setcachedevice(penum, w2));

	if (code < 0)
	    return code;
    }

    /* No metrics modification, do the stroke or fill now. */

    /* Push the l.s.b. for .type1addpath if necessary. */
    if (psb != 0) {
	push(2);
	make_real(op - 1, psb[0]);
	make_real(op, psb[1]);
    }
    *exec_cont = cont;
    return 0;
}

/*
 * Get the CharString data corresponding to a glyph.  Return typecheck
 * if it isn't a string.
 */
private bool charstring_is_notdef_proc(const gs_memory_t *mem, const ref *);
private int charstring_make_notdef(gs_glyph_data_t *, gs_font *);
int
zchar_charstring_data(gs_font *font, const ref *pgref, gs_glyph_data_t *pgd)
{
    ref *pcstr;

    if (dict_find(&pfont_data(font)->CharStrings, pgref, &pcstr) <= 0)
	return_error(e_undefined);
    if (!r_has_type(pcstr, t_string)) {
	/*
	 * The ADOBEPS4 Windows driver replaces the .notdef entry of
	 * otherwise normal Type 1 fonts with the procedure
	 *	{pop 0 0 setcharwidth}
	 * To prevent this from making the font unembeddable in PDF files
	 * (with our present font-writing code), we recognize this as a
	 * special case and return a Type 1 CharString consisting of
	 *	0 0 hsbw endchar
	 */
	if (font->FontType == ft_encrypted &&
	    charstring_is_notdef_proc(font->memory, pcstr)
	    )
	    return charstring_make_notdef(pgd, font);
	else
	    return_error(e_typecheck);
    }
    gs_glyph_data_from_string(pgd, pcstr->value.const_bytes, r_size(pcstr),
			      NULL);
    return 0;
}
private bool
charstring_is_notdef_proc(const gs_memory_t *mem, const ref *pcstr)
{
    if (r_is_array(pcstr) && r_size(pcstr) == 4) {
	ref elts[4];
	long i;

	for (i = 0; i < 4; ++i)
	    array_get(mem, pcstr, i, &elts[i]);
	if (r_has_type(&elts[0], t_name) &&
	    r_has_type(&elts[1], t_integer) && elts[1].value.intval == 0 &&
	    r_has_type(&elts[2], t_integer) && elts[2].value.intval == 0 &&
	    r_has_type(&elts[3], t_name)
	    ) {
	    ref nref;

	    name_enter_string(mem, "pop", &nref);
	    if (name_eq(&elts[0], &nref)) {
	        name_enter_string(mem, "setcharwidth", &nref);
		if (name_eq(&elts[3], &nref))
		    return true;
	    }
	}
    }
    return false;
}
private int
charstring_make_notdef(gs_glyph_data_t *pgd, gs_font *font)
{
    gs_font_type1 *const pfont = (gs_font_type1 *)font;
    static const byte char_data[4] = {
	139,			/* 0 */
	139,			/* 0 */
	c1_hsbw,
	cx_endchar
    };
    uint len = max(pfont->data.lenIV, 0) + sizeof(char_data);
    byte *chars = gs_alloc_string(font->memory, len, "charstring_make_notdef");

    if (chars == 0)
	return_error(e_VMerror);
    gs_glyph_data_from_string(pgd, chars, len, font);
    if (pfont->data.lenIV < 0)
	memcpy(chars, char_data, sizeof(char_data));
    else {
	crypt_state state = crypt_charstring_seed;

	memcpy(chars + pfont->data.lenIV, char_data, sizeof(char_data));
	gs_type1_encrypt(chars, chars, len, &state);
    }
    return 0;
}

/*
 * Enumerate the next glyph from a directory.  This is essentially a
 * wrapper around dict_first/dict_next to implement the enumerate_glyph
 * font procedure.
 *
 * Note that *prdict will be null if the font is a subfont of a
 * CIDFontType 0 CIDFont.
 */
int
zchar_enumerate_glyph(const gs_memory_t *mem, const ref *prdict, int *pindex, gs_glyph *pglyph)
{
    int index = *pindex - 1;
    ref elt[2];

    if (!r_has_type(prdict, t_dictionary))
	return 0;		/* *pindex was 0, is still 0 */
    if (index < 0)
	index = dict_first(prdict);
next:
    index = dict_next(prdict, index, elt);
    *pindex = index + 1;
    if (index >= 0) {
	switch (r_type(elt)) {
	    case t_integer:
		*pglyph = gs_min_cid_glyph + elt[0].value.intval;
		break;
	    case t_name:
	        *pglyph = name_index(mem, elt);
		break;
	    default:		/* can't handle it */
		goto next;
	}
    }
    return 0;
}
