/* Pango
 * gscriptx.c: Routines for handling X fonts
 *
 * Copyright (C) 1999 Red Hat Software
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#include <X11/Xlib.h>
#include "pangox.h"
#include <ctype.h>
#include <math.h>
#include <stdio.h>
#include <string.h>

typedef struct _PangoXFont PangoXFont;
typedef struct _PangoXFontMap PangoXFontMap;
typedef struct _PangoXSubfontInfo PangoXSubfontInfo;

typedef struct _PangoXFamilyEntry PangoXFamilyEntry;
typedef struct _PangoXFontEntry PangoXFontEntry;

struct _PangoXFontEntry
{
  char *xlfd_prefix;
  PangoFontDescription description;
};

struct _PangoXFamilyEntry
{
  char *family_name;
  GSList *font_entries;
};

struct _PangoXSubfontInfo
{
  char *xlfd;
  XFontStruct *font_struct;
};

struct _PangoXFont
{
  PangoFont font;
  Display *display;

  char **fonts;
  int n_fonts;

  /* hash table mapping from charset-name to array of PangoXSubfont ids,
   * of length n_fonts
   */
  GHashTable *subfonts_by_charset;
  
  PangoXSubfontInfo **subfonts;

  int n_subfonts;
  int max_subfonts;
};

struct _PangoXFontMap
{
  PangoFontMap fontmap;

  Display *display;

  GHashTable *families;

  int n_fonts;
};

/* This is the largest field length we will accept. If a fontname has a field
   larger than this we will skip it. */
#define XLFD_MAX_FIELD_LEN 64
#define MAX_FONTS 32767

/* These are the field numbers in the X Logical Font Description fontnames,
   e.g. -adobe-courier-bold-o-normal--25-180-100-100-m-150-iso8859-1 */
typedef enum
{
  XLFD_FOUNDRY		= 0,
  XLFD_FAMILY		= 1,
  XLFD_WEIGHT		= 2,
  XLFD_SLANT		= 3,
  XLFD_SET_WIDTH	= 4,
  XLFD_ADD_STYLE	= 5,
  XLFD_PIXELS		= 6,
  XLFD_POINTS		= 7,
  XLFD_RESOLUTION_X	= 8,
  XLFD_RESOLUTION_Y	= 9,
  XLFD_SPACING		= 10,
  XLFD_AVERAGE_WIDTH	= 11,
  XLFD_CHARSET		= 12,
  XLFD_NUM_FIELDS     
} FontField;

const struct {
  const gchar *text;
  PangoWeight value;
} weights_map[] = {
  { "light",     300 },
  { "regular",   400 },
  { "book",      400 },
  { "medium",    500 },
  { "semibold",  600 },
  { "demibold",  600 },
  { "bold",      700 },
  { "extrabold", 800 },
  { "ultrabold", 800 },
  { "heavy",     900 },
  { "black",     900 }
};

const struct {
  const gchar *text;
  PangoStyle value;
} styles_map[] = {
  { "r", PANGO_STYLE_NORMAL },
  { "i", PANGO_STYLE_ITALIC },
  { "o", PANGO_STYLE_OBLIQUE }
};

const struct {
  const gchar *text;
  PangoStretch value;
} stretches_map[] = {
  { "normal",        PANGO_STRETCH_NORMAL },
  { "semicondensed", PANGO_STRETCH_SEMI_CONDENSED },
  { "condensed",     PANGO_STRETCH_CONDENSED },
};

static void       pango_x_font_map_destroy    (PangoFontMap           *fontmap);
static PangoFont *pango_x_font_map_load_font  (PangoFontMap           *fontmap,
					       PangoFontDescription   *desc,
					       double                  size);
static void       pango_x_font_map_list_fonts (PangoFontMap           *fontmap,
					       PangoFontDescription ***descs,
					       int                    *n_descs);

static PangoXSubfontInfo * pango_x_find_subfont    (PangoFont          *font,
						    PangoXSubfont       subfont_index);
static XCharStruct *       pango_x_get_per_char    (PangoFont          *font,
						    PangoXSubfontInfo  *subfont,
						    guint16             char_index);
static void                pango_x_font_destroy    (PangoFont          *font);
static gboolean            pango_x_find_glyph      (PangoFont          *font,
						    PangoGlyph          glyph,
						    PangoXSubfontInfo **subfont_return,
						    XCharStruct       **charstruct_return);
static XFontStruct *       pango_x_get_font_struct (PangoFont          *font,
						    PangoXSubfontInfo  *info);

static gboolean pango_x_is_xlfd_font_name (const char *fontname);
static char *  pango_x_get_xlfd_field    (const char *fontname,
					   FontField    field_num,
					   char       *buffer);
static void     pango_x_insert_font       (PangoXFontMap *fontmap,
					   char       *fontname);

static GList *fontmaps;

PangoFontClass pango_x_font_class = {
  pango_x_font_destroy
};

PangoFontMapClass pango_x_font_map_class = {
  pango_x_font_map_destroy,
  pango_x_font_map_load_font,
  pango_x_font_map_list_fonts
};

static PangoFontMap *
pango_x_font_map_for_display (Display *display)
{
  PangoXFontMap *xfontmap;
  GList *tmp_list = fontmaps;
  char **xfontnames;
  int num_fonts, i;

  while (tmp_list)
    {
      xfontmap = tmp_list->data;

      if (xfontmap->display == display)
	{
	  pango_font_map_ref ((PangoFontMap *)xfontmap);
	  return (PangoFontMap *)xfontmap;
	}
    }

  xfontmap = g_new (PangoXFontMap, 1);

  xfontmap->fontmap.klass = &pango_x_font_map_class;
  xfontmap->display = display;
  xfontmap->families = g_hash_table_new (g_str_hash, g_str_equal);
  xfontmap->n_fonts = 0;

  pango_font_map_init ((PangoFontMap *)xfontmap);

  /* Get a maximum of MAX_FONTS fontnames from the X server.
     Use "-*" as the pattern rather than "-*-*-*-*-*-*-*-*-*-*-*-*-*-*" since
     the latter may result in fonts being returned which don't actually exist.
     xlsfonts also uses "*" so I think it's OK. "-*" gets rid of aliases. */
  xfontnames = XListFonts (xfontmap->display, "-*", MAX_FONTS, &num_fonts);
  if (num_fonts == MAX_FONTS)
    g_warning("MAX_FONTS exceeded. Some fonts may be missing.");

  /* Insert the font families into the main table */
  for (i = 0; i < num_fonts; i++)
    {
      if (pango_x_is_xlfd_font_name (xfontnames[i]))
	pango_x_insert_font (xfontmap, xfontnames[i]);
    }
  
  XFreeFontNames (xfontnames);
  
  return (PangoFontMap *)xfontmap;
}

static void
pango_x_font_map_destroy (PangoFontMap *fontmap)
{
  fontmaps = g_list_remove (fontmaps, fontmap);

  g_free (fontmap);
}

static PangoFont *
pango_x_font_map_load_font (PangoFontMap         *fontmap,
			    PangoFontDescription *description,
			    double                size)
{
  PangoXFontMap *xfontmap = (PangoXFontMap *)fontmap;
  PangoXFamilyEntry *family_entry;
  PangoXFontEntry *font_entry;
  PangoFont *result = NULL;
  GSList *tmp_list;
  gchar *name;
  int size_decipoints;

  g_return_val_if_fail (size > 0, NULL);
  
  name = g_strdup (description->family_name);
  g_strdown (name);

  size_decipoints = floor(size*10 + 0.5);

  family_entry = g_hash_table_lookup (xfontmap->families, name);
  if (family_entry)
    {
      tmp_list = family_entry->font_entries;
      while (tmp_list)
	{
	  font_entry = tmp_list->data;
	  
	  if (font_entry->description.style == description->style &&
	      font_entry->description.variant == description->variant &&
	      font_entry->description.weight == description->weight &&
	      font_entry->description.stretch == description->stretch)
	    {
	      /* Construct and XLFD for the sized font. The first 5 fields of the
	       * XLFD are stored in the xlfd_prefix.
	       */

	      char *xlfd = g_strdup_printf ("%s*-%d-*-*-*-*-*-*", font_entry->xlfd_prefix, size_decipoints);
	      /* FIXME: cache fonts */
	      result = pango_x_load_font (xfontmap->display, xlfd);
	      g_free (xlfd);
	      
	      break;
	    }
	  
	  tmp_list = tmp_list->next;
	}
    }

  g_free (name);
  return result;
}

typedef struct
{
  int n_found;
  PangoFontDescription **descs;
} ListFontsInfo;


static void
list_fonts_foreach (gpointer key, gpointer value, gpointer user_data)
{
  PangoXFamilyEntry *entry = value;
  ListFontsInfo *info = user_data;

  GSList *tmp_list = entry->font_entries;

  while (tmp_list)
    {
      PangoXFontEntry *font_entry = tmp_list->data;
      
      info->descs[info->n_found++] = pango_font_description_copy (&font_entry->description);
      tmp_list = tmp_list->next;
    }
}

static void
pango_x_font_map_list_fonts (PangoFontMap           *fontmap,
			     PangoFontDescription ***descs,
			     int                    *n_descs)
{
  PangoXFontMap *xfontmap = (PangoXFontMap *)fontmap;
  ListFontsInfo info;

  if (!n_descs)
    return;

  *n_descs = xfontmap->n_fonts;
  if (!descs)
    return;

  *descs = g_new (PangoFontDescription *, xfontmap->n_fonts);

  info.descs = *descs;
  info.n_found = 0;
  
  g_hash_table_foreach (xfontmap->families, list_fonts_foreach, &info);
}

/*
 * Returns TRUE if the fontname is a valid XLFD.
 * (It just checks if the number of dashes is 14, and that each
 * field < XLFD_MAX_FIELD_LEN  characters long - that's not in the XLFD but it
 * makes it easier for me).
 */
static gboolean
pango_x_is_xlfd_font_name (const char *fontname)
{
  int i = 0;
  int field_len = 0;
  
  while (*fontname)
    {
      if (*fontname++ == '-')
	{
	  if (field_len > XLFD_MAX_FIELD_LEN) return FALSE;
	  field_len = 0;
	  i++;
	}
      else
	field_len++;
    }
  
  return (i == 14) ? TRUE : FALSE;
}

/*
 * This fills the buffer with the specified field from the X Logical Font
 * Description name, and returns it. If fontname is NULL or the field is
 * longer than XFLD_MAX_FIELD_LEN it returns NULL.
 * Note: For the charset field, we also return the encoding, e.g. 'iso8859-1'.
 */
static char*
pango_x_get_xlfd_field (const char *fontname,
			 FontField    field_num,
			 char       *buffer)
{
  const char *t1, *t2;
  int countdown, len, num_dashes;
  
  if (!fontname)
    return NULL;
  
  /* we assume this is a valid fontname...that is, it has 14 fields */
  
  countdown = field_num;
  t1 = fontname;
  while (*t1 && (countdown >= 0))
    if (*t1++ == '-')
      countdown--;
  
  num_dashes = (field_num == XLFD_CHARSET) ? 2 : 1;
  for (t2 = t1; *t2; t2++)
    { 
      if (*t2 == '-' && --num_dashes == 0)
	break;
    }
  
  if (t1 != t2)
    {
      /* Check we don't overflow the buffer */
      len = (long) t2 - (long) t1;
      if (len > XLFD_MAX_FIELD_LEN - 1)
	return NULL;
      strncpy (buffer, t1, len);
      buffer[len] = 0;
      /* Convert to lower case. */
      g_strdown (buffer);
    }
  else
    strcpy(buffer, "(nil)");
  
  return buffer;
}

/* This inserts the given fontname into the FontInfo table.
   If a FontInfo already exists with the same family and foundry, then the
   fontname is added to the FontInfos list of fontnames, else a new FontInfo
   is created and inserted in alphabetical order in the table. */
static void
pango_x_insert_font (PangoXFontMap *xfontmap,
		     char  *fontname)
{
  PangoFontDescription description;
  char family_buffer[XLFD_MAX_FIELD_LEN];
  char weight_buffer[XLFD_MAX_FIELD_LEN];
  char slant_buffer[XLFD_MAX_FIELD_LEN];
  char set_width_buffer[XLFD_MAX_FIELD_LEN];
  GSList *tmp_list;
  PangoXFamilyEntry *family_entry;
  PangoXFontEntry *font_entry;
  int i;

  /* Convert the XLFD into a PangoFontDescription */
  
  description.family_name = pango_x_get_xlfd_field (fontname, XLFD_FAMILY, family_buffer);
  g_strdown (description.family_name);
  
  if (!description.family_name)
    return;

  description.style = PANGO_STYLE_NORMAL;
  if (pango_x_get_xlfd_field (fontname, XLFD_SLANT, slant_buffer))
    {
      for (i=0; i<G_N_ELEMENTS(styles_map); i++)
	{
	  if (!strcmp (styles_map[i].text, slant_buffer))
	    {
	      description.style = styles_map[i].value;
	      break;
	    }
	}
    }
  else
    strcpy (slant_buffer, "*");

  description.variant = PANGO_VARIANT_NORMAL;
  
  description.weight = PANGO_WEIGHT_NORMAL;
  if (pango_x_get_xlfd_field (fontname, XLFD_WEIGHT, weight_buffer))
    {
      for (i=0; i<G_N_ELEMENTS(weights_map); i++)
	{
	  if (!strcmp (weights_map[i].text, weight_buffer))
	    {
	      description.weight = weights_map[i].value;
	      break;
	    }
	}
    }
  else
    strcpy (weight_buffer, "*");

  description.stretch = PANGO_STRETCH_NORMAL;
  if (pango_x_get_xlfd_field (fontname, XLFD_SET_WIDTH, set_width_buffer))
    {
      for (i=0; i<G_N_ELEMENTS(stretches_map); i++)
	{
	  if (!strcmp (stretches_map[i].text, set_width_buffer))
	    {
	      description.stretch = stretches_map[i].value;
	      break;
	    }
	}
    }
  else
    strcpy (set_width_buffer, "*");

  family_entry = g_hash_table_lookup (xfontmap->families, description.family_name);
  if (!family_entry)
    {
      family_entry = g_new (PangoXFamilyEntry, 1);
      family_entry->family_name = g_strdup (description.family_name);
      family_entry->font_entries = NULL;

      g_hash_table_insert (xfontmap->families, family_entry->family_name, family_entry);
    }

  tmp_list = family_entry->font_entries;
  while (tmp_list)
    {
      font_entry = tmp_list->data;

      if (font_entry->description.style == description.style &&
	  font_entry->description.variant == description.variant &&
	  font_entry->description.weight == description.weight &&
	  font_entry->description.stretch == description.stretch)
	return;

      tmp_list = tmp_list->next;
    }

  font_entry = g_new (PangoXFontEntry, 1);
  font_entry->description = description;
  font_entry->description.family_name = family_entry->family_name;

  font_entry->xlfd_prefix = g_strconcat ("-*-",
					 family_buffer,
					 "-",
					 weight_buffer,
					 "-",
					 slant_buffer,
					 "-",
					 set_width_buffer,
					 "--",
					 NULL);

  family_entry->font_entries = g_slist_append (family_entry->font_entries, font_entry);
  xfontmap->n_fonts++;
}


PangoContext *
pango_x_get_context (Display *display)
{
  PangoContext *result;

  result = pango_context_new ();
  pango_context_add_font_map (result, pango_x_font_map_for_display (display));

  return result;
}

/**
 * pango_x_load_font:
 * @display: the X display
 * @spec:    a comma-separated list of XLFD's
 *
 * Load up a logical font based on a "fontset" style
 * text specification.
 *
 * Returns a new #PangoFont
 */
PangoFont *
pango_x_load_font (Display *display,
		   char    *spec)
{
  PangoXFont *result;

  g_return_val_if_fail (display != NULL, NULL);
  g_return_val_if_fail (spec != NULL, NULL);
  
  result = g_new (PangoXFont, 1);

  result->display = display;

  pango_font_init (&result->font);
  result->font.klass = &pango_x_font_class;

  result->fonts = g_strsplit(spec, ",", -1);

  for (result->n_fonts = 0; result->fonts[result->n_fonts]; result->n_fonts++)
    /* Nothing */

  result->subfonts_by_charset = g_hash_table_new (g_str_hash, g_str_equal);
  result->subfonts = g_new (PangoXSubfontInfo *, 1);

  result->n_subfonts = 0;
  result->max_subfonts = 1;

  return (PangoFont *)result;
}
 
/**
 * pango_x_render:
 * @display: the X display
 * @d:       the drawable on which to draw string
 * @gc:      the graphics context
 * @font:    the font in which to draw the string
 * @glyphs:  the glyph string to draw
 * @x:       the x position of start of string
 * @y:       the y position of baseline
 *
 * Render a PangoGlyphString onto an X drawable
 */
void 
pango_x_render  (Display           *display,
		 Drawable           d,
		 GC                 gc,
		 PangoFont         *font,
		 PangoGlyphString  *glyphs,
		 int               x, 
		 int               y)
{
  /* Slow initial implementation. For speed, it should really
   * collect the characters into runs, and draw multiple
   * characters with each XDrawString16 call.
   */
  Font old_fid = None;
  XFontStruct *fs;
  int i;

  g_return_if_fail (display != NULL);
  g_return_if_fail (glyphs != NULL);
  
  for (i=0; i<glyphs->num_glyphs; i++)
    {
      guint16 index = PANGO_X_GLYPH_INDEX (glyphs->glyphs[i].glyph);
      guint16 subfont_index = PANGO_X_GLYPH_SUBFONT (glyphs->glyphs[i].glyph);
      PangoXSubfontInfo *subfont;
      
      XChar2b c;

      subfont = pango_x_find_subfont (font, subfont_index);
      if (subfont)
	{
	  c.byte1 = index / 256;
	  c.byte2 = index % 256;

	  fs = pango_x_get_font_struct (font, subfont);
	  if (!fs)
	    continue;
	  
	  if (fs->fid != old_fid)
	    {
	      XSetFont (display, gc, fs->fid);
	      old_fid = fs->fid;
	    }
	  
	  XDrawString16 (display, d, gc,
			 x + glyphs->glyphs[i].geometry.x_offset / 72,
			 y + glyphs->glyphs[i].geometry.y_offset / 72,
			 &c, 1);
	}

      x += glyphs->glyphs[i].geometry.width / 72;
    }
}

/**
 * pango_x_glyph_extents:
 * @font:     a #PangoFont
 * @glyph:    the glyph to measure
 * @lbearing: left bearing of glyph (result)
 * @rbearing: right bearing of glyph (result)
 * @width:    width of glyph (result)
 * @ascent:   ascent of glyph (result)
 * @descent:  descent of glyph (result)
 * @logical_ascent: The vertical distance from the baseline to the
 *                  bottom of the line above.
 * @logical_descent: The vertical distance from the baseline to the
 *                   top of the line below.
 *
 * Compute the measurements of a single glyph in pixels.
 */
void 
pango_x_glyph_extents (PangoFont       *font,
		       PangoGlyph       glyph,
		       int            *lbearing, 
		       int            *rbearing,
		       int            *width, 
		       int            *ascent, 
		       int            *descent,
		       int            *logical_ascent,
		       int            *logical_descent)
{
  XCharStruct *cs;
  PangoXSubfontInfo *subfont;

  if (pango_x_find_glyph (font, glyph, &subfont, &cs))
    {
      if (lbearing)
	*lbearing = cs->lbearing;
      if (rbearing)
	*rbearing = cs->rbearing;
      if (width)
	*width = cs->width;
      if (ascent)
	*ascent = cs->ascent;
      if (descent)
	*descent = cs->descent;
      if (logical_ascent)
	*logical_ascent = subfont->font_struct->ascent;
      if (logical_descent)
	*logical_descent = subfont->font_struct->descent;
    }
  else
    {
      if (lbearing)
	*lbearing = 0;
      if (rbearing)
	*rbearing = 0;
      if (width)
	*width = 0;
      if (ascent)
	*ascent = 0;
      if (descent)
	*descent = 0;
      if (logical_ascent)
	*logical_ascent = 0;
      if (logical_descent)
	*logical_descent = 0;
    }
}

/**
 * pango_x_extents:
 * @font:     a #PangoFont
 * @glyphs:   the glyph string to measure
 * @lbearing: left bearing of string (result)
 * @rbearing: right bearing of string (result)
 * @width:    width of string (result)
 * @ascent:   ascent of string (result)
 * @descent:  descent of string (result)
 * @logical_ascent: The vertical distance from the baseline to the
 *                  bottom of the line above.
 * @logical_descent: The vertical distance from the baseline to the
 *                   top of the line below.
 *
 * Compute the measurements of a glyph string in pixels.
 * The number of parameters here is clunky - it might be
 * nicer to use structures as in XmbTextExtents.
 */
void 
pango_x_extents (PangoFont        *font,
		 PangoGlyphString *glyphs,
		 int             *lbearing, 
		 int             *rbearing,
		 int             *width, 
		 int             *ascent, 
		 int             *descent,
		 int             *logical_ascent,
		 int             *logical_descent)
{
  PangoXSubfontInfo *subfont;
  XCharStruct *cs;

  int i;

  int t_lbearing = 0;
  int t_rbearing = 0;
  int t_ascent = 0;
  int t_descent = 0;
  int t_logical_ascent = 0;
  int t_logical_descent = 0;
  int t_width = 0;

  g_return_if_fail (font != NULL);
  g_return_if_fail (glyphs != NULL);
  
  for (i=0; i<glyphs->num_glyphs; i++)
    {
      PangoGlyphGeometry *geometry = &glyphs->glyphs[i].geometry;
      
      if (pango_x_find_glyph (font, glyphs->glyphs[i].glyph, &subfont, &cs))
	{
	  if (i == 0)
	    {
	      t_lbearing = cs->lbearing - geometry->x_offset / 72;
	      t_rbearing = cs->rbearing + geometry->x_offset / 72;
	      t_ascent = cs->ascent + geometry->y_offset / 72;
	      t_descent = cs->descent - geometry->y_offset / 72;
	      
	      t_logical_ascent = subfont->font_struct->ascent + geometry->y_offset / 72;
	      t_logical_descent = subfont->font_struct->descent - geometry->y_offset / 72;
	    }
	  else
	    {
	      t_lbearing = MAX (t_lbearing,
				cs->lbearing - geometry->x_offset / 72 - t_width);
	      t_rbearing = MAX (t_rbearing,
				t_width + cs->rbearing + geometry->x_offset / 72);
	      t_ascent = MAX (t_ascent, cs->ascent + geometry->y_offset / 72);
	      t_descent = MAX (t_descent, cs->descent - geometry->y_offset / 72);
	      t_logical_ascent = MAX (t_logical_ascent, subfont->font_struct->ascent + geometry->y_offset / 72);
	      t_logical_descent = MAX (t_logical_descent, subfont->font_struct->descent - geometry->y_offset / 72);
	    }
	}
      
      t_width += geometry->width / 72;
    }

  if (lbearing)
    *lbearing = t_lbearing;
  if (rbearing)
    *rbearing = t_rbearing;
  if (width)
    *width = t_width;
  if (ascent)
    *ascent = t_ascent;
  if (descent)
    *descent = t_descent;
  if (logical_ascent)
    *logical_ascent = t_logical_ascent;
  if (logical_descent)
    *logical_descent = t_logical_descent;
}

/* Compare the tail of a to b */
static gboolean
match_end (char *a, char *b)
{
  size_t len_a = strlen (a);
  size_t len_b = strlen (b);

  if (len_b > len_a)
    return FALSE;
  else
    return (strcmp (a + len_a - len_b, b) == 0);
}

/* Substitute in a charset into an XLFD. Return the
 * (g_malloc'd) new name, or NULL if the XLFD cannot
 * match the charset
 */
static char *
name_for_charset (char *xlfd, char *charset)
{
  char *p;
  char *dash_charset = g_strconcat ("-", charset, NULL);
  char *result = NULL;
  int ndashes = 0;

  for (p = xlfd; *p; p++)
    if (*p == '-')
      ndashes++;
  
  if (ndashes == 14) /* Complete XLFD */
    {
      if (match_end (xlfd, "-*-*"))
	{
	  result = g_malloc (strlen (xlfd) - 4 + strlen (dash_charset) + 1);
	  strncpy (result, xlfd, strlen (xlfd) - 4);
	  strcpy (result + strlen (xlfd) - 4, dash_charset);
	}
      if (match_end (xlfd, dash_charset))
	result = g_strdup (xlfd);
    }
  else if (ndashes == 13)
    {
      if (match_end (xlfd, "-*"))
	{
	  result = g_malloc (strlen (xlfd) - 2 + strlen (dash_charset) + 1);
	  strncpy (result, xlfd, strlen (xlfd) - 2);
	  strcpy (result + strlen (xlfd) - 2, dash_charset);
	}
      if (match_end (xlfd, dash_charset))
	result = g_strdup (xlfd);
    }
  else
    {
      if (match_end (xlfd, "*"))
	{
	  result = g_malloc (strlen (xlfd) + strlen (dash_charset) + 1);
	  strcpy (result, xlfd);
	  strcpy (result + strlen (xlfd), dash_charset);
	}
      if (match_end (xlfd, dash_charset))
	result = g_strdup (xlfd);
    }

  g_free (dash_charset);
  return result;
}

/**
 * pango_x_list_subfonts:
 * @font: a PangoFont
 * @charsets: the charsets to list subfonts for.
 * @n_charsets: the number of charsets in @charsets
 * @subfont_ids: location to store a pointer to an array of subfont IDs for each found subfont
 *               the result must be freed using g_free()
 * @subfont_charsets: location to store a pointer to an array of subfont IDs for each found subfont
 *               the result must be freed using g_free()
 * 
 * Returns number of charsets found
 **/
int
pango_x_list_subfonts (PangoFont        *font,
		       char            **charsets,
		       int               n_charsets,
		       PangoXSubfont   **subfont_ids,
		       int             **subfont_charsets)
{
  PangoXFont *xfont = (PangoXFont *)font;
  PangoXSubfont **subfont_lists;
  int i, j;
  int n_subfonts = 0;

  g_return_val_if_fail (font != NULL, 0);
  g_return_val_if_fail (n_charsets == 0 || charsets != NULL, 0);

  subfont_lists = g_new (PangoXSubfont *, n_charsets);

  for (j=0; j<n_charsets; j++)
    {
      subfont_lists[j] = g_hash_table_lookup (xfont->subfonts_by_charset, charsets[j]);
      if (!subfont_lists[j])
	{
	  subfont_lists[j] = g_new (PangoXSubfont, xfont->n_fonts);
	  
	  for (i = 0; i < xfont->n_fonts; i++)
	    {
	      PangoXSubfontInfo *info = NULL;
	      char *xlfd = name_for_charset (xfont->fonts[i], charsets[j]);
	      
	      if (xlfd)
		{
		  int count;
		  char **names = XListFonts (xfont->display, xlfd, 1, &count);
		  if (count > 0)
		    {
		      info = g_new (PangoXSubfontInfo, 1);
		      
		      info->xlfd = g_strdup (names[0]);
		      info->font_struct = NULL;
		    }

		  g_free (xlfd);
		}
	      
	      if (info)
		{
		  xfont->n_subfonts++;
		  
		  if (xfont->n_subfonts > xfont->max_subfonts)
		    {
		      xfont->max_subfonts *= 2;
		      xfont->subfonts = g_renew (PangoXSubfontInfo *, xfont->subfonts, xfont->max_subfonts);
		    }
		  
		  xfont->subfonts[xfont->n_subfonts - 1] = info;
		  subfont_lists[j][i] = xfont->n_subfonts;
		}
	      else
		subfont_lists[j][i] = 0;
	    }

	  g_hash_table_insert (xfont->subfonts_by_charset, g_strdup (charsets[j]), subfont_lists[j]);
	}

      for (i = 0; i < xfont->n_fonts; i++)
	if (subfont_lists[j][i])
	  n_subfonts++;
    }

  *subfont_ids = g_new (PangoXSubfont, n_subfonts);
  *subfont_charsets = g_new (int, n_subfonts);

  n_subfonts = 0;

  for (i=0; i<xfont->n_fonts; i++)
    for (j=0; j<n_charsets; j++)
      if (subfont_lists[j][i])
	{
	  (*subfont_ids)[n_subfonts] = subfont_lists[j][i];
	  (*subfont_charsets)[n_subfonts] = j;
	  n_subfonts++;
	}

  g_free (subfont_lists);

  return n_subfonts;
}

gboolean
pango_x_has_glyph (PangoFont       *font,
		   PangoGlyph  glyph)
{
  g_return_val_if_fail (font != NULL, FALSE);

  return pango_x_find_glyph (font, glyph, NULL, NULL);
}

static void
subfonts_foreach (gpointer key, gpointer value, gpointer data)
{
  g_free (key);
  g_free (value);
}

static void
pango_x_font_destroy (PangoFont *font)
{
  PangoXFont *xfont = (PangoXFont *)font;
  int i;

  for (i=0; i<xfont->n_subfonts; i++)
    {
      PangoXSubfontInfo *info = xfont->subfonts[i];

      g_free (info->xlfd);
      if (info->font_struct)
	XFreeFont (xfont->display, info->font_struct);

      g_free (info);
    }

  g_free (xfont->subfonts);

  g_hash_table_foreach (xfont->subfonts_by_charset, subfonts_foreach, NULL);
  g_hash_table_destroy (xfont->subfonts_by_charset);

  g_strfreev (xfont->fonts);
  g_free (font);
}

/* Utility functions */

static XFontStruct *
pango_x_get_font_struct (PangoFont *font, PangoXSubfontInfo *info)
{
  PangoXFont *xfont = (PangoXFont *)font;
  
  if (!info->font_struct)
    {
      info->font_struct = XLoadQueryFont (xfont->display, info->xlfd);
      if (!info->font_struct)
	g_warning ("Cannot load font for XLFD '%s\n", info->xlfd);
    }
  
  return info->font_struct;
}

static PangoXSubfontInfo *
pango_x_find_subfont (PangoFont  *font,
		      PangoXSubfont subfont_index)
{
  PangoXFont *xfont = (PangoXFont *)font;
  
  if (subfont_index < 1 || subfont_index > xfont->n_subfonts)
    {
      g_warning ("Invalid subfont %d", subfont_index);
      return NULL;
    }
  
  return xfont->subfonts[subfont_index-1];
}

static XCharStruct *
pango_x_get_per_char (PangoFont         *font,
		      PangoXSubfontInfo *subfont,
		      guint16            char_index)
{
  XFontStruct *fs;

  int index;
  guint8 byte1;
  guint8 byte2;

  byte1 = char_index / 256;
  byte2 = char_index % 256;

  fs = pango_x_get_font_struct (font, subfont);
  if (!fs)
    return NULL;
	  
  if ((fs->min_byte1 == 0) && (fs->max_byte1 == 0))
    {
      if (byte2 < fs->min_char_or_byte2 || byte2 > fs->max_char_or_byte2)
	return NULL;
      
      index = byte2 - fs->min_char_or_byte2;
    }
  else
    {
      if (byte1 < fs->min_byte1 || byte1 > fs->max_byte1 ||
	  byte2 < fs->min_char_or_byte2 || byte2 > fs->max_char_or_byte2)
	return FALSE;
      
      index = ((byte1 - fs->min_byte1) *
	       (fs->max_char_or_byte2 - fs->min_char_or_byte2 + 1)) +
	byte2 - fs->min_char_or_byte2;
    }
  
  if (fs->per_char)
    return &fs->per_char[index];
  else
    return &fs->min_bounds;
}

static gboolean
pango_x_find_glyph (PangoFont *font,
		    PangoGlyph glyph,
		    PangoXSubfontInfo **subfont_return,
		    XCharStruct **charstruct_return)
{
  PangoXSubfontInfo *subfont;
  XCharStruct *cs;

  guint16 char_index = PANGO_X_GLYPH_INDEX (glyph);
  guint16 subfont_index = PANGO_X_GLYPH_SUBFONT (glyph);

  subfont = pango_x_find_subfont (font, subfont_index);
  if (!subfont)
    return FALSE;
  
  cs = pango_x_get_per_char (font, subfont, char_index);

  if (cs && (cs->lbearing != cs->rbearing))
    {
      if (subfont_return)
	*subfont_return = subfont;

      if (charstruct_return)
	*charstruct_return = cs;
      
      return TRUE;
    }
  else
    return FALSE;
}