/* Copyright (C) 1999, 2000 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 General Public License for full details.
  
  Everyone is granted permission to copy, modify and redistribute GNU
  Ghostscript, but only under the conditions described in the GNU General
  Public License.  A copy of this license is supposed to have been given
  to you along with GNU Ghostscript so you can know your rights and
  responsibilities.  It should be in a file named COPYING.  Among other
  things, the copyright notice and this notice must be preserved on all
  copies.
*/

/*$RCSfile: gdevpdfw.c,v $ $Revision: 1.5.2.3 $ */
/* Font writing for pdfwrite driver. */
#include "memory_.h"
#include "string_.h"
#include "gx.h"
#include "gsbittab.h"
#include "gserrors.h"
#include "gsmalloc.h"		/* for patching font memory */
#include "gsmatrix.h"
#include "gsutil.h"		/* for bytes_compare */
#include "gxfcid.h"
#include "gxfont.h"
#include "gxfont0.h"
#include "gdevpdfx.h"
#include "gdevpdff.h"
#include "gdevpsf.h"
#include "scommon.h"

/* Get the ID of various kinds of resources, with type checking. */
inline private long
pdf_font_id(const pdf_font_t *pdfont)
{
    return pdf_resource_id((const pdf_resource_t *)pdfont);
}
inline private long
pdf_font_descriptor_id(const pdf_font_descriptor_t *pfd)
{
    return pdf_resource_id((const pdf_resource_t *)pfd);
}
inline private long
pdf_char_proc_id(const pdf_char_proc_t *pcp)
{
    return pdf_resource_id((const pdf_resource_t *)pcp);
}

/* Write CIDSystemInfo for a CIDFont or CMap. */
private void
pdf_write_CIDSystemInfo(gx_device_pdf *pdev,
			const gs_cid_system_info_t *pcidsi)
{
    stream *s = pdev->strm;

    stream_puts(s, "/CISystemInfo<<\n/Registry");
    s_write_ps_string(s, pcidsi->Registry.data, pcidsi->Registry.size,
		      PRINT_HEX_NOT_OK);
    stream_puts(s, "\n/Ordering");
    s_write_ps_string(s, pcidsi->Ordering.data, pcidsi->Ordering.size,
		      PRINT_HEX_NOT_OK);
    pprintd1(s, "\n/Supplement %d\n>>\n", pcidsi->Supplement);
}

/* Write the Widths for a font. */
private int
pdf_write_Widths(gx_device_pdf *pdev, int first, int last,
		 const int widths[256])
{
    stream *s = pdev->strm;
    int i;

    pprintd2(s, "/FirstChar %d/LastChar %d/Widths[", first, last);
    for (i = first; i <= last; ++i)
	pprintd1(s, (i & 15 ? " %d" : "\n%d"), widths[i]);
    stream_puts(s, "]\n");
    return 0;
}

/* Write a FontBBox dictionary element. */
private int
pdf_write_font_bbox(gx_device_pdf *pdev, const gs_int_rect *pbox)
{
    stream *s = pdev->strm;
    /* AR 4 doesn't like fonts with empty FontBBox which
     * happens when the font contains only space characters.
     * Small bbox causes AR 4 to display a hairline. So we use
     * the full BBox.
     */ 
    int x= pbox->q.x + ((pbox->p.x == pbox->q.x) ? 1000 : 0);
    int y= pbox->q.y + ((pbox->p.y == pbox->q.y) ? 1000 : 0);

    pprintd4(s, "/FontBBox[%d %d %d %d]",
	     pbox->p.x, pbox->p.y, x, y);
    return 0;
}

/* Write a synthesized bitmap font resource. */
private int
pdf_write_synthesized_type3(gx_device_pdf *pdev, const pdf_font_t *pef)
{
    stream *s;
    gs_int_rect bbox;
    int widths[256];

    memset(&bbox, 0, sizeof(bbox));
    memset(widths, 0, sizeof(widths));
    pdf_open_separate(pdev, pdf_font_id(pef));
    s = pdev->strm;
    pprints1(s, "<</Type/Font/Name/%s/Subtype/Type3", pef->frname);
    pprintld1(s, "/Encoding %ld 0 R/CharProcs", pdev->embedded_encoding_id);

    /* Write the CharProcs. */
    {
	const pdf_char_proc_t *pcp;
	int w;

	stream_puts(s, "<<");
	/* Write real characters. */
	for (pcp = pef->char_procs; pcp; pcp = pcp->char_next) {
	    bbox.p.y = min(bbox.p.y, pcp->y_offset);
	    bbox.q.x = max(bbox.q.x, pcp->width);
	    bbox.q.y = max(bbox.q.y, pcp->height + pcp->y_offset);
	    widths[pcp->char_code] = pcp->x_width;
	    pprintld2(s, "/a%ld\n%ld 0 R", (long)pcp->char_code,
		      pdf_char_proc_id(pcp));
	}
	/* Write space characters. */
	for (w = 0; w < countof(pef->spaces); ++w) {
	    byte ch = pef->spaces[w];

	    if (ch) {
		pprintld2(s, "/a%ld\n%ld 0 R", (long)ch,
			  pdev->space_char_ids[w]);
		widths[ch] = w + X_SPACE_MIN;
	    }
	}
	stream_puts(s, ">>");
    }

    pdf_write_font_bbox(pdev, &bbox);
    stream_puts(s, "/FontMatrix[1 0 0 1 0 0]");
    pdf_write_Widths(pdev, 0, pef->num_chars - 1, widths);
    stream_puts(s, ">>\n");
    pdf_end_separate(pdev);
    return 0;
}

/* Write a font descriptor. */
int
pdf_write_FontDescriptor(gx_device_pdf *pdev, const pdf_font_descriptor_t *pfd)
{
    gs_font *font = pfd->base_font;
    bool is_subset =
	pdf_has_subset_prefix(pfd->FontName.chars, pfd->FontName.size);
    long cidset_id = 0;		/* pro forma initialization */
    stream *s;
    int code = 0;

    /* If this is a CIDFont subset, write the CIDSet now. */
    if (font && is_subset) {
	switch (pfd->values.FontType) {
	case ft_CID_encrypted:
	case ft_CID_TrueType: {
	    int i;

	    cidset_id = pdf_begin_separate(pdev);
	    s = pdev->strm;
	    /****** ADD COMPRESSION + ASCII85 ******/
	    pprintd1(s, "<</Length %d>>stream\n", (int)pfd->chars_used.size);
	    for (i = 0; i < pfd->chars_used.size; ++i)
		stream_putc(s, byte_reverse_bits[pfd->chars_used.data[i]]);
	    stream_puts(s, "endstream\n");
	    pdf_end_separate(pdev);
	}
	default:
	    break;
	}
    }
    pdf_open_separate(pdev, pdf_font_descriptor_id(pfd));
    s = pdev->strm;
    stream_puts(s, "<</Type/FontDescriptor/FontName");
    pdf_put_name(pdev, pfd->FontName.chars, pfd->FontName.size);
    if (font) {		/* not a built-in font */
	param_printer_params_t params;
	printer_param_list_t rlist;
	gs_param_list *const plist = (gs_param_list *)&rlist;

	pdf_write_font_bbox(pdev, &pfd->values.FontBBox);
	params = param_printer_params_default;
	code = s_init_param_printer(&rlist, &params, s);
	if (code >= 0) {
#define DESC_INT(str, memb)\
 {str, gs_param_type_int, offset_of(pdf_font_descriptor_t, values.memb)}
	    static const gs_param_item_t required_items[] = {
		DESC_INT("Ascent", Ascent),
		DESC_INT("CapHeight", CapHeight),
		DESC_INT("Descent", Descent),
		DESC_INT("ItalicAngle", ItalicAngle),
		DESC_INT("StemV", StemV),
		gs_param_item_end
	    };
	    static const gs_param_item_t optional_items[] = {
		DESC_INT("AvgWidth", AvgWidth),
		DESC_INT("Leading", Leading),
		DESC_INT("MaxWidth", MaxWidth),
		DESC_INT("MissingWidth", MissingWidth),
		DESC_INT("StemH", StemH),
		DESC_INT("XHeight", XHeight),
		gs_param_item_end
	    };
#undef DESC_INT
	    int Flags = pfd->values.Flags;
	    pdf_font_descriptor_t defaults;

	    /*
	     * Hack: make all embedded subset TrueType fonts "symbolic" to
	     * work around undocumented assumptions in Acrobat Reader.
	     */
	    if (pfd->values.FontType == ft_TrueType &&
		pdf_has_subset_prefix(pfd->FontName.chars, pfd->FontName.size))
		Flags = (Flags & ~(FONT_IS_ADOBE_ROMAN)) | FONT_IS_SYMBOLIC;
	    param_write_int(plist, "Flags", &Flags);
	    gs_param_write_items(plist, pfd, NULL, required_items);
	    memset(&defaults, 0, sizeof(defaults));
	    gs_param_write_items(plist, pfd, &defaults, optional_items);
	    s_release_param_printer(&rlist);
	}
	if (is_subset) {
	    switch (pfd->values.FontType) {
	    case ft_CID_encrypted:
	    case ft_CID_TrueType:
		pprintld1(s, "/CIDSet %ld 0 R\n", cidset_id);
		break;
	    case ft_composite:
		return_error(gs_error_rangecheck);
	    default: {
		gs_glyph subset_glyphs[256];
		uint subset_size = psf_subset_glyphs(subset_glyphs, font,
						     pfd->chars_used.data);
		int i;

		stream_puts(s, "/CharSet(");
		for (i = 0; i < subset_size; ++i) {
		    uint len;
		    const char *str = font->procs.callbacks.glyph_name
			(subset_glyphs[i], &len);

		    /* Don't include .notdef. */
		    if (bytes_compare((const byte *)str, len,
				      (const byte *)".notdef", 7))
			pdf_put_name(pdev, (const byte *)str, len);
		}
		stream_puts(s, ")\n");
	    }
	    }
	}
	if (pfd->FontFile_id) {
	    const char *FontFile_key;

	    switch (pfd->values.FontType) {
	    case ft_TrueType:
	    case ft_CID_TrueType:
		FontFile_key = "/FontFile2";
		break;
	    default:
		code = gs_note_error(gs_error_rangecheck);
		/* falls through */
	    case ft_encrypted:
		if (pdev->CompatibilityLevel < 1.2) {
		    FontFile_key = "/FontFile";
		    break;
		}
		/* For PDF 1.2 and later, write Type 1 fonts as Type1C. */
	    case ft_encrypted2:
	    case ft_CID_encrypted:
		FontFile_key = "/FontFile3";
		break;
	    }
	    stream_puts(s, FontFile_key);
	    pprintld1(s, " %ld 0 R", pfd->FontFile_id);
	}
    }
    stream_puts(s, ">>\n");
    pdf_end_separate(pdev);
    return code;
}

/*
 * Write a font resource, including Widths and/or Encoding if relevant,
 * but not the FontDescriptor or embedded font data.  Note that the
 * font itself may not be available.
 */
private int
pdf_write_font_resource(gx_device_pdf *pdev, const pdf_font_t *pef,
			const gs_const_string *pfname,
			const gs_const_string *pbfname)
{
    stream *s;
    const pdf_font_descriptor_t *pfd = pef->FontDescriptor;
    static const char *const encoding_names[] = {
	KNOWN_REAL_ENCODING_NAMES
    };

    pdf_open_separate(pdev, pdf_font_id(pef));
    s = pdev->strm;
    switch (pef->FontType) {
    case ft_composite:
	stream_puts(s, "<</Subtype/Type0");
	goto bfname;
    case ft_encrypted:
    case ft_encrypted2: {
	if (pef->is_MM_instance) {
	/*
	 * If the font is a Multiple Master instance, it should be
	 * identified as such.  However, Acrobat Reader doesn't seem to
	 * recognize the MMType1 subtype, but will accept MM Type 1
	 * instances happily if they are tagged as Type1 (!).
	 */
#if 0
	    stream_puts(s, "<</Subtype/MMType1");
	    /****** NAME IS WRONG ******/
#else
	    stream_puts(s, "<</Subtype/Type1");
#endif
	} else {
	    stream_puts(s, "<</Subtype/Type1");
	}
    }
    bfname:
	stream_puts(s, "/BaseFont");
	pdf_put_name(pdev, pbfname->data, pbfname->size);
	break;
    case ft_CID_encrypted:
	stream_puts(s, "<</Subtype/CIDFontType0");
	/****** REQUIRES FONT TO EXIST ******/
	pdf_write_CIDSystemInfo(pdev, &((const gs_font_cid0 *)pfd->base_font)->
				cidata.common.CIDSystemInfo);
	goto bfname;
    case ft_CID_TrueType:
	stream_puts(s, "<</Subtype/CIDFontType2");
	/****** REQUIRES FONT TO EXIST ******/
	pdf_write_CIDSystemInfo(pdev, &((const gs_font_cid2 *)pfd->base_font)->
				cidata.common.CIDSystemInfo);
	goto ttname;
    case ft_TrueType:
	stream_puts(s, "<</Subtype/TrueType");
    ttname:
	stream_puts(s, "/BaseFont");
	/****** WHAT ABOUT STYLE INFO? ******/
	pdf_put_name(pdev, pbfname->data, pbfname->size);
	break;
    default:
	return_error(gs_error_rangecheck);
    }
    pprintld1(s, "/Type/Font/Name/R%ld", pdf_font_id(pef));
    if (pef->index < 0 || pfd->base_font || pfd->FontFile_id)
	pprintld1(s, "/FontDescriptor %ld 0 R", pdf_font_descriptor_id(pfd));
    if (pef->write_Widths)
	pdf_write_Widths(pdev, pef->FirstChar, pef->LastChar, pef->Widths);
    /****** WRITE CIDFont [D]W[2] ******/
    if (pef->Differences) {
	long diff_id = pdf_obj_ref(pdev);
	int prev = 256;
	int i;

	pprintld1(s, "/Encoding %ld 0 R>>\n", diff_id);
	pdf_end_separate(pdev);
	pdf_open_separate(pdev, diff_id);
	s = pdev->strm;
	stream_puts(s, "<</Type/Encoding");
	if (pef->BaseEncoding != ENCODING_INDEX_UNKNOWN)
	    pprints1(s, "/BaseEncoding/%s", encoding_names[pef->BaseEncoding]);
	stream_puts(s, "/Differences[");
	for (i = 0; i < 256; ++i)
	    if (pef->Differences[i].str.data != 0) {
		if (i != prev + 1)
		    pprintd1(s, "\n%d", i);
		pdf_put_name(pdev, pef->Differences[i].str.data,
			     pef->Differences[i].str.size);
		prev = i;
	    }
	stream_puts(s, "]");
    } else if (pef->BaseEncoding != ENCODING_INDEX_UNKNOWN) {
	pprints1(s, "/Encoding/%s", encoding_names[pef->BaseEncoding]);
    }
    stream_puts(s, ">>\n");
    return pdf_end_separate(pdev);
}

/* Register a font for eventual writing (embedded or not). */
private GS_NOTIFY_PROC(pdf_font_notify_proc);
typedef struct pdf_font_notify_s {
    gs_memory_t *memory;	/* used to allocate this object */
    gx_device_pdf *pdev;
    pdf_font_t *pdfont;		/* 0 if only for base_font */
    pdf_font_descriptor_t *pfd;	/* 0 if not for base_font */
} pdf_font_notify_t;
gs_private_st_ptrs3(st_pdf_font_notify, pdf_font_notify_t, "pdf_font_notify_t",
		    pdf_font_notify_enum_ptrs, pdf_font_notify_reloc_ptrs,
		    pdev, pdfont, pfd);
int
pdf_register_font(gx_device_pdf *pdev, gs_font *font, pdf_font_t *ppf)
{
    /*
     * Note that we do this allocation in stable font->memory, not
     * pdev->pdf_memory.
     */
    pdf_font_descriptor_t *pfd = ppf->FontDescriptor;
    gs_font *base_font = pfd->base_font;
    gs_memory_t *fn_memory = gs_memory_stable(font->memory);
    pdf_font_notify_t *pfn =
	gs_alloc_struct(fn_memory, pdf_font_notify_t,
			&st_pdf_font_notify, "pdf_register_font");
    int code;

    if (pfn == 0)
	return_error(gs_error_VMerror);
    pfn->memory = fn_memory;
    pfn->pdev = pdev;
    pfn->pfd = pfd;
    if (base_font == 0 || pfd->notified)
	pfn->pfd = 0;
    else if (base_font != font) {
	/*
	 * We need two notifications: one for ppf->font, one for
	 * base_font.  Create the latter first.
	 */
	pfn->pdfont = 0;
	if_debug4('_', "[_]register 0x%lx: pdf_font_descriptor_t 0x%lx => 0x%lx, id %ld\n",
		  (ulong)pfn, (ulong)pfd, (ulong)base_font, base_font->id);
	code = gs_font_notify_register(base_font, pdf_font_notify_proc, pfn);
	if (code < 0)
	    return 0;
	pfn = gs_alloc_struct(fn_memory, pdf_font_notify_t,
			      &st_pdf_font_notify, "pdf_register_font");
	if (pfn == 0)
	    return_error(gs_error_VMerror);
	pfn->memory = fn_memory;
	pfn->pdev = pdev;
	pfn->pfd = 0;
    }
    pfd->notified = true;
    pfn->pdfont = ppf;
#ifdef DEBUG
    if_debug4('_', "[_]register 0x%lx: pdf_font_t 0x%lx => 0x%lx, id %ld\n",
	      (ulong)pfn, (ulong)ppf, (ulong)font, font->id);
    if (pfn->pfd)
	if_debug3('_',
		  "                pdf_font_descriptor_t 0x%lx => 0x%lx, id %ld\n",
		  (ulong)pfd, (ulong)pfd->base_font, pfd->base_font->id);
#endif
    ppf->font = font;
    return gs_font_notify_register(font, pdf_font_notify_proc, pfn);
}
private int
pdf_finalize_font_descriptor(gx_device_pdf *pdev, pdf_font_descriptor_t *pfd)
{
    gs_font *font = pfd->base_font;
    int code =
	(font ? pdf_compute_font_descriptor(pdev, pfd, font, NULL) : 0);

    if (code >= 0) {
	if (pfd->FontFile_id)
	    code = pdf_write_embedded_font(pdev, pfd);
	else
	    code = pdf_write_FontDescriptor(pdev, pfd);
	pfd->written = true;
    }
    pfd->base_font = 0;		/* clean up for GC */
    return code;
}
private int
pdf_font_notify_proc(void *vpfn /*proc_data*/, void *event_data)
{
    pdf_font_notify_t *const pfn = vpfn;
    gx_device_pdf *const pdev = pfn->pdev;
    pdf_font_t *const ppf = pfn->pdfont;	/* may be 0 */
    pdf_font_descriptor_t *pfd = pfn->pfd;	/* may be 0 */
    int code = 0;

    if (event_data)
	return 0;		/* unknown event */

    if (ppf) {
	/*
	 * The font of this pdf_font is about to be freed.  Just clear the
	 * pointer.
	 */
	gs_font *const font = ppf->font;

	if_debug4('_',
		  "[_]  notify 0x%lx: pdf_font_t 0x%lx => 0x%lx, id %ld\n",
		  (ulong)pfn, (ulong)ppf, (ulong)font, font->id);
	gs_font_notify_unregister(font, pdf_font_notify_proc, vpfn);
	ppf->font = 0;
    }

    if (pfd) {
	/*
	 * The base_font of this FontDescriptor is about to be freed.
	 * Write the FontDescriptor and, if relevant, the FontFile.
	 */
	gs_font *const font = pfd->base_font;
	gs_memory_t *save_memory = font->memory;

	if_debug4('_',
		  "[_]  notify 0x%lx: pdf_font_descriptor_t 0x%lx => 0x%lx, id %ld\n",
		  (ulong)pfn, (ulong)pfd, (ulong)font, font->id);
	gs_font_notify_unregister(font, pdf_font_notify_proc, vpfn);
	/*
	 * HACK: temporarily patch the font's memory to one that we know is
	 * available even during GC or restore.  (Eventually we need to fix
	 * this by prohibiting implementations of font_info and glyph_info
	 * from doing any allocations.)
	 */
	font->memory = &gs_memory_default;
	code = pdf_finalize_font_descriptor(pdev, pfd);
	font->memory = save_memory;
    }
    gs_free_object(pfn->memory, vpfn, "pdf_font_notify_proc");
    return code;
}

/* Write out the font resources when wrapping up the output. */
private void
pdf_font_unreg_proc(void *vpfn /*proc_data*/)
{
    pdf_font_notify_t *const pfn = vpfn;

    gs_free_object(pfn->memory, vpfn, "pdf_font_unreg_proc");
}
/* Write out the font resources when wrapping up the output. */
int
pdf_write_font_resources(gx_device_pdf *pdev)
{
    int j;

    for (j = 0; j < NUM_RESOURCE_CHAINS; ++j) {
	pdf_font_t *ppf;
	pdf_font_descriptor_t *pfd;

	for (ppf = (pdf_font_t *)pdev->resources[resourceFont].chains[j];
	     ppf != 0; ppf = ppf->next
	     ) {
	    if (PDF_FONT_IS_SYNTHESIZED(ppf))
		pdf_write_synthesized_type3(pdev, ppf);
	    else if (!ppf->skip) {
		gs_const_string font_name;

		pfd = ppf->FontDescriptor;
		font_name.data = pfd->FontName.chars;
		font_name.size = pfd->FontName.size;
		/*
		 * If the font is based on one of the built-in fonts,
		 * we already ensured it uses the built-in name.
		 * If it is a subset, we must write the Widths even if
		 * it is a built-in font.
		 */
		if (pdf_has_subset_prefix(font_name.data, font_name.size))
		    ppf->write_Widths = true;
		pdf_write_font_resource(pdev, ppf, &font_name, &font_name);
		if (ppf->font)
		    gs_notify_unregister_calling(&ppf->font->notify_list,
						 pdf_font_notify_proc, NULL,
						 pdf_font_unreg_proc);
	    }
	}
	for (pfd = (pdf_font_descriptor_t *)pdev->resources[resourceFontDescriptor].chains[j];
	     pfd != 0; pfd = pfd->next
	     ) {
	    if (!pfd->written) {
		pdf_finalize_font_descriptor(pdev, pfd);
		if (pfd->base_font)
		    gs_notify_unregister_calling(&pfd->base_font->notify_list,
						 pdf_font_notify_proc, NULL,
						 pdf_font_unreg_proc);
	    }
	}
    }
    return 0;
}
