/* Copyright (C) 2001-2023 Artifex Software, Inc.
   All Rights Reserved.

   This software is provided AS-IS with no warranty, either express or
   implied.

   This software is distributed under license and may not be copied,
   modified or distributed except as expressly authorized under the terms
   of the license contained in the file LICENSE in this distribution.

   Refer to licensing information at http://www.artifex.com or contact
   Artifex Software, Inc.,  39 Mesa Street, Suite 108A, San Francisco,
   CA 94129, USA, for further information.
*/


/* Font copying for high-level output */

#ifndef gxfcopy_INCLUDED
#  define gxfcopy_INCLUDED

#include "gsccode.h"
#include "gsmatrix.h"
#include "gsfont.h"

/*
 * Copy a font, aside from its glyphs.  Note that PostScript-specific data
 * -- that is, data that do not appear in the C structure that is the
 * relevant subclass of gs_font -- are NOT copied.  In particular,
 * Metrics[2], CDevProc, and FontInfo are not copied, except for the
 * information returned by font->procs.font_info (see the definition of
 * gs_font_info_t in gxfont.h).
 *
 * Note that in some cases the font must have a definition for the "not
 * defined" glyph, as noted below, or a rangecheck error occurs.
 *
 * The following FontTypes are supported:
 *
 *	Type 1, Type 2 - Encoding and CharStrings are not copied.  Subrs and
 *	GlobalSubrs (for CFFs) are copied; OtherSubrs are not copied.  The
 *	font must have a glyph named .notdef; its definition is copied.
 *
 *	Type 42 (TrueType) - Encoding and CharStrings are not copied.  The
 *	TrueType glyf and loca tables are not copied, nor are the bogus
 *	Adobe gdir, glyx, and locx "tables".  If the font has a definition
 *	for a glyph named .notdef (in the CharStrings dictionary), the
 *	definition is copied.
 *
 *	CIDFontType 0 (Type 1/2-based CIDFonts) - the glyph data are not
 *	copied.  The Type 1/2 subfonts *are* copied, as are the Subrs (both
 *	local and global).
 *
 *	CIDFontType 2 (TrueType-based CIDFonts) - the glyph data and CIDMap
 *	are not copied.
 *
 * The resulting font supports querying (font_info, glyph_info, etc.) and
 * rendering (glyph_outline, etc.), but it does not support make_font.
 *
 * max_reserved_glyphs limits the maount of space allocated for the glyph names
 * and glyph outlines of type 1 or 2 fonts. -1 reserves as many as required for
 * a full copy of the original font. This is used by pdfwrite to limit the size
 * of a copy when creating a subset font.
 */
int gs_copy_font(gs_font *font, const gs_matrix *orig_matrix,
                    gs_memory_t *mem, gs_font **pfont_new,
                    int max_reserved_glyphs);

int gs_free_copied_font(gs_font *font);

/*
 * Copy a glyph, including any sub-glyphs.  The destination font ("copied"
 * argument) must be a font created by gs_copy_font.  The source font
 * ("font" argument) must have the same FontType as the destination, and in
 * addition must be "compatible" with it as described under the individual
 * FontTypes just below; however, gs_copy_glyph does not check
 * compatibility.
 *
 * If any glyph has already been copied but does not have the same
 * definition as the one being copied now, gs_copy_glyph returns an
 * invalidaccess error.  If the top-level glyph has already been copied
 * (with the same definition), gs_copy_glyph returns 1.  Otherwise,
 * gs_copy_glyph returns 0.
 *
 *	Type 1, Type 2 - the destination and source must have the same
 *	Subrs.  glyph must be a name (not an integer).  Copies the
 *	CharString entry.  Note that the Type 1/2 'seac' operator requires
 *	copying not only the sub-glyphs but their Encoding entries as well.
 *
 *	Type 42 - the destination and source must have compatible tables
 *	other than glyf and loca.  In practice this means that the source
 *	must be the same font that was passed to gs_copy_font.  If glyph is
 *	an integer, it is interpreted as a GID; if glyph is a name, both
 *	the CharString entry and the glyph data are copied.
 *
 *	CIDFontType 0 - the destination and source must have the same Subrs,
 *	and the Type 1/2 subfont(s) referenced by the glyph(s) being copied
 *	must be compatible.  glyph must be a CID.  Copies the CharString.
 *
 *	CIDFontType 2 - compatibility is as for Type 42.  glyph must be a
 *	CID (integer), not a GID.  Copies the glyph data and the CIDMap
 *	entry.
 *
 * Metrics[2] and CDevProc in the source font are ignored.  Currently,
 * for CIDFontType 2 fonts with MetricsCount != 0, the metrics attached to
 * the individual glyph outlines are also ignored (not copied).
 */
int gs_copy_glyph(gs_font *font, gs_glyph glyph, gs_font *copied);

/*
 * Copy a glyph with additional checking options.  If options includes
 * COPY_GLYPH_NO_OLD, then if the top-level glyph has already been copied,
 * return an invalidaccess error rather than 1.  If options includes
 * COPY_GLYPH_NO_NEW, then if the top-level glyph has *not* already been
 * copied, return an undefined error rather than 0.
 *
 * COPY_GLYPH_USE_GSUB directs the code to try using a TrueType GSUB table
 * to find a replacement for a glyph. Bug #691574
 *
 * Returns an error if a glyph is added after calling copied_order_font.
 */
#define COPY_GLYPH_NO_OLD 1
#define COPY_GLYPH_NO_NEW 2
#define COPY_GLYPH_BY_INDEX 4
#define COPY_GLYPH_USE_GSUB 8
int gs_copy_glyph_options(gs_font *font, gs_glyph glyph, gs_font *copied,
                          int options);

int gs_copied_font_free_glyphs(gs_font *font);
int gs_copied_font_free_data(gs_font *font);

/*
 * Add an encoding entry to a copied font.  If the given encoding entry is
 * not empty and is not the same as the new value, gs_copied_font_encode
 * returns an invalidaccess error.
 *
 * The action depends on FontType as follows:
 *
 *	Type 1, Type 2 - glyph must be a name, not a CID (integer).  Makes
 *	an entry in the font's Encoding.  A glyph by that name must exist
 *	in the copied font.
 *
 *	Type 42 - same as Type 1.
 *
 *	CIDFontType 0 - gives an error.
 *
 *	CIDFontType 2 - gives an error.
 */
int gs_copied_font_add_encoding(gs_font *copied, gs_char chr, gs_glyph glyph);

/*
 * Copy all the glyphs and, if relevant, Encoding entries from a font.  This
 * is equivalent to copying the glyphs and Encoding entries individually,
 * and returns errors under the same conditions.
 */
int gs_copy_font_complete(gs_font *font, gs_font *copied);

/*
 * Check whether specified glyphs can be copied from another font.
 * It means that (1) fonts have same hinting parameters and
 * (2) font subsets for the specified glyph set don't include different
 * outlines or metrics. Possible returned values :
 * 0 (incompatible), 1 (compatible), < 0 (error)
 */
int gs_copied_can_copy_glyphs(const gs_font *cfont, const gs_font *ofont,
                    gs_glyph *glyphs, int num_glyphs, int glyphs_step,
                    bool check_hinting);

/* Extension glyphs may be added to a font to resolve
   glyph name conflicts while conwerting a PDF Widths into Metrics.
   This function drops them before writing out an embedded font. */
int copied_drop_extension_glyphs(gs_font *cfont);

/* Order font to avoid a serialization indeterminism.
   An indeterminizm can happen due to PS name indices
   depend on memory allocation.
   Must not add glyphs after calling this function.
   After calling this function, enumerate_glyph
   enumerates glyphs in the alphabetic order of glyph names.
   Currently works for Type 1,2 only,
   because other fonts type don't use PS name indices
   when enumerate glyphs.
*/
int copied_order_font(gs_font *font);

/* Get .notdef glyph. */
gs_glyph copied_get_notdef(const gs_font *font);

#endif /* gxfcopy_INCLUDED */