libchimara/style.c

   1 #include "style.h"
   2 #include <stdio.h>
   3 #include <fcntl.h>
   4
   5 extern GPrivate *glk_data_key;
   6
   7 static gboolean style_accept(GScanner *scanner, GTokenType token);
   8 static gboolean style_accept_style_selector(GScanner *scanner);
   9 static gboolean style_accept_style_hint(GScanner *scanner, GtkTextTag *current_tag);
  10 static void style_add_tag_to_textbuffer(gpointer key, gpointer tag, gpointer tag_table);
  11 static void style_table_copy(gpointer key, gpointer tag, gpointer target_table);
  12 static GtkTextTag* gtk_text_tag_copy(GtkTextTag *tag);
  13
  14 /**
  15  * glk_set_style:
  16  * @styl: The style to apply
  17  *
  18  * Changes the style of the current output stream. @styl should be one of the
  19  * <code>style_</code> constants listed above. However, any value is actually
  20  * legal; if the interpreter does not recognize the style value, it will treat
  21  * it as %style_Normal.
  22  * <note><para>
  23  *  This policy allows for the future definition of styles without breaking old
  24  *  Glk libraries.
  25  * </para></note>
  26  */
  27 void
  28 glk_set_style(glui32 styl)
  29 {
  30         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
  31         g_return_if_fail(glk_data->current_stream != NULL);
  32         glk_set_style_stream(glk_data->current_stream, styl);
  33 }
  34
  35 static const gchar* TAG_NAMES[] = {
  36         "normal",
  37         "emphasized",
  38         "preformatted",
  39         "header",
  40         "subheader",
  41         "alert",
  42         "note",
  43         "block-quote",
  44         "input",
  45         "user1",
  46         "user2"
  47 };
  48
  49 /* Internal function: mapping from style enum to tag name */
  50 static gchar*
  51 get_tag_name(glui32 style)
  52 {
  53         if(style >= style_NUMSTYLES) {
  54                 WARNING("Unsupported style");
  55                 return "normal";
  56         } else {
  57                 return (gchar*) TAG_NAMES[style];
  58         }
  59 }
  60
  61 /**
  62  * glk_set_style_stream:
  63  * @str: Output stream to change the style of
  64  * @styl: The style to apply
  65  *
  66  * This changes the style of the stream @str. See glk_set_style().
  67  */
  68 void
  69 glk_set_style_stream(strid_t str, glui32 styl) {
  70         if(str->window == NULL)
  71                 return;
  72
  73         flush_window_buffer(str->window);
  74         str->style = get_tag_name(styl);
  75 }
  76
  77 /* Internal function: call this to initialize the default styles to a textbuffer. */
  78 void
  79 style_init_textbuffer(GtkTextBuffer *buffer)
  80 {
  81         g_return_if_fail(buffer != NULL);
  82
  83         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
  84         if( G_UNLIKELY(!glk_data->style_initialized) ) {
  85                 style_init();
  86         }
  87         g_hash_table_foreach(glk_data->current_styles->text_buffer, style_add_tag_to_textbuffer, gtk_text_buffer_get_tag_table(buffer));
  88 }
  89
  90 /* Internal function: call this to initialize the default styles to a textgrid. */
  91 void
  92 style_init_textgrid(GtkTextBuffer *buffer)
  93 {
  94         g_return_if_fail(buffer != NULL);
  95
  96         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
  97         if( G_UNLIKELY(!glk_data->style_initialized) ) {
  98                 style_init();
  99         }
 100         g_hash_table_foreach(glk_data->current_styles->text_grid, style_add_tag_to_textbuffer, gtk_text_buffer_get_tag_table(buffer));
 101 }
 102
 103 /* Internal function used to iterate over the default text tag table, applying them to a textbuffer */
 104 static void
 105 style_add_tag_to_textbuffer(gpointer key, gpointer tag, gpointer tag_table)
 106 {
 107         gtk_text_tag_table_add( tag_table, gtk_text_tag_copy(tag) );
 108 }
 109
 110 /* Internal function used to iterate over a style table, copying it */
 111 static void
 112 style_table_copy(gpointer key, gpointer tag, gpointer target_table)
 113 {
 114         g_return_if_fail(key != NULL);
 115         g_return_if_fail(tag != NULL);
 116         g_return_if_fail(target_table != NULL);
 117
 118         g_hash_table_insert(target_table, key, gtk_text_tag_copy( GTK_TEXT_TAG(tag) ));
 119 }
 120
 121 /* Internal function that copies a text tag */
 122 static GtkTextTag*
 123 gtk_text_tag_copy(GtkTextTag *tag)
 124 {
 125         GtkTextTag *copy;
 126
 127         g_return_val_if_fail(tag != NULL, NULL);
 128
 129         copy = gtk_text_tag_new(tag->name);
 130         gtk_text_attributes_copy_values(tag->values, copy->values);
 131
 132         #define _COPY_FLAG(flag) copy->flag = tag->flag
 133                 _COPY_FLAG (bg_color_set);
 134                 _COPY_FLAG (bg_color_set);
 135                 _COPY_FLAG (bg_stipple_set);
 136                 _COPY_FLAG (fg_color_set);
 137                 _COPY_FLAG (fg_stipple_set);
 138                 _COPY_FLAG (justification_set);
 139                 _COPY_FLAG (left_margin_set);
 140                 _COPY_FLAG (indent_set);
 141                 _COPY_FLAG (rise_set);
 142                 _COPY_FLAG (strikethrough_set);
 143                 _COPY_FLAG (right_margin_set);
 144                 _COPY_FLAG (pixels_above_lines_set);
 145                 _COPY_FLAG (pixels_below_lines_set);
 146                 _COPY_FLAG (pixels_inside_wrap_set);
 147                 _COPY_FLAG (tabs_set);
 148                 _COPY_FLAG (underline_set);
 149                 _COPY_FLAG (wrap_mode_set);
 150                 _COPY_FLAG (bg_full_height_set);
 151                 _COPY_FLAG (invisible_set);
 152                 _COPY_FLAG (editable_set);
 153                 _COPY_FLAG (language_set);
 154         #undef _COPY_FLAG
 155
 156         return copy;
 157 }
 158
 159 /* Internal function that reads the default styles from a CSS file */
 160 void
 161 style_init()
 162 {
 163         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
 164         GHashTable *default_text_grid_styles = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, g_object_unref);
 165         GHashTable *default_text_buffer_styles = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, g_object_unref);
 166         GHashTable *current_text_grid_styles = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, g_object_unref);
 167         GHashTable *current_text_buffer_styles = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, g_object_unref);
 168         GtkTextTag *tag;
 169
 170         /* Create the CSS file scanner */
 171         GScanner *scanner = g_scanner_new(NULL);
 172
 173         int f = open(glk_data->css_file, O_RDONLY);
 174         g_return_if_fail(f != -1);
 175         g_scanner_input_file(scanner, f);
 176         scanner->input_name = glk_data->css_file;
 177         scanner->config->cset_identifier_first = G_CSET_a_2_z G_CSET_A_2_Z "#";
 178         scanner->config->cset_identifier_nth = G_CSET_a_2_z G_CSET_A_2_Z "-_" G_CSET_DIGITS;
 179         scanner->config->symbol_2_token = TRUE;
 180         scanner->config->cpair_comment_single = NULL;
 181         scanner->config->scan_float = FALSE;
 182
 183         /* Initialise the default styles */
 184         g_hash_table_insert(default_text_grid_styles, "normal", gtk_text_tag_new("normal"));
 185
 186         tag = gtk_text_tag_new("emphasized");
 187         g_object_set(tag, "style", PANGO_STYLE_ITALIC, "style-set", TRUE, NULL);
 188         g_hash_table_insert(default_text_grid_styles, "emphasized", tag);
 189
 190         tag = gtk_text_tag_new("preformatted");
 191         g_object_set(tag, "font-desc", glk_data->monospace_font_desc, NULL);
 192         g_hash_table_insert(default_text_grid_styles, "preformatted", tag);
 193
 194         tag = gtk_text_tag_new("header");
 195         g_object_set(tag, "size-points", 18.0, "weight", PANGO_WEIGHT_BOLD, NULL);
 196         g_hash_table_insert(default_text_grid_styles, "header", tag);
 197
 198         tag = gtk_text_tag_new("subheader");
 199         g_object_set(tag, "size-points", 14.0, "weight", PANGO_WEIGHT_BOLD, NULL);
 200         g_hash_table_insert(default_text_grid_styles, "subheader", tag);
 201
 202         tag = gtk_text_tag_new("alert");
 203         g_object_set(tag, "foreground", "#aa0000", "weight", PANGO_WEIGHT_BOLD, NULL);
 204         g_hash_table_insert(default_text_grid_styles, "alert", tag);
 205
 206         tag = gtk_text_tag_new("note");
 207         g_object_set(tag, "foreground", "#aaaa00", "weight", PANGO_WEIGHT_BOLD, NULL);
 208         g_hash_table_insert(default_text_grid_styles, "note", tag);
 209
 210         tag = gtk_text_tag_new("block-quote");
 211         g_object_set(tag, "justification", GTK_JUSTIFY_CENTER, "style", PANGO_STYLE_ITALIC, NULL);
 212         g_hash_table_insert(default_text_grid_styles, "block-quote", tag);
 213
 214         g_hash_table_insert(default_text_grid_styles, "input", gtk_text_tag_new("input"));
 215         g_hash_table_insert(default_text_grid_styles, "user1", gtk_text_tag_new("user1"));
 216         g_hash_table_insert(default_text_grid_styles, "user2", gtk_text_tag_new("user2"));
 217
 218         g_hash_table_foreach(default_text_grid_styles, style_table_copy, default_text_buffer_styles);
 219         glk_data->default_styles->text_grid = default_text_grid_styles;
 220         glk_data->default_styles->text_buffer = default_text_buffer_styles;
 221
 222         /* Run the scanner over the CSS file, overriding defaults */
 223         while( g_scanner_peek_next_token(scanner) != G_TOKEN_EOF) {
 224                 if( !style_accept_style_selector(scanner) )
 225                         break;
 226         }
 227
 228         /* Set the current style to a copy of the default style */
 229         g_hash_table_foreach(default_text_grid_styles, style_table_copy, current_text_grid_styles);
 230         g_hash_table_foreach(default_text_buffer_styles, style_table_copy, current_text_buffer_styles);
 231         glk_data->current_styles->text_grid = current_text_grid_styles;
 232         glk_data->current_styles->text_buffer = current_text_buffer_styles;
 233
 234         g_scanner_destroy(scanner);
 235
 236         glk_data->style_initialized = TRUE;
 237 }
 238
 239 /* Internal function: parses a token */
 240 static gboolean
 241 style_accept(GScanner *scanner, GTokenType token)
 242 {
 243         GTokenType next = g_scanner_get_next_token(scanner);
 244         if(next != token ) {
 245                 g_scanner_unexp_token(scanner, token, NULL, NULL, NULL, "CSS Error", 1);
 246                 return FALSE;
 247         } else {
 248                 return TRUE;
 249         }
 250 }
 251
 252 /* Internal function: parses a style selector */
 253 static gboolean
 254 style_accept_style_selector(GScanner *scanner)
 255 {
 256         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
 257
 258         GtkTextTag *current_tag;
 259         gchar *field;
 260         GTokenType token = g_scanner_get_next_token(scanner);
 261         GTokenValue value = g_scanner_cur_value(scanner);
 262
 263         if(
 264                 token != G_TOKEN_IDENTIFIER ||
 265                 ( strcmp(value.v_identifier, "buffer") && strcmp(value.v_identifier, "grid") )
 266         ) {
 267                 g_scanner_error(scanner, "CSS Error: buffer/grid expected");
 268                 return FALSE;
 269         }
 270
 271         field = g_strdup(value.v_identifier);
 272
 273         if( !style_accept(scanner, '.') )
 274                 return FALSE;
 275
 276         token = g_scanner_get_next_token(scanner);
 277         value = g_scanner_cur_value(scanner);
 278
 279         if(token != G_TOKEN_IDENTIFIER) {
 280                 g_scanner_error(scanner, "CSS Error: style selector expected");
 281                 return FALSE;
 282         }
 283
 284         if( !strcmp(field, "buffer") )
 285                 current_tag = g_hash_table_lookup(glk_data->default_styles->text_buffer, value.v_identifier);
 286         else
 287                 current_tag = g_hash_table_lookup(glk_data->default_styles->text_grid, value.v_identifier);
 288
 289         if(current_tag == NULL) {
 290                 g_scanner_error(scanner, "CSS Error: invalid style identifier");
 291                 return FALSE;
 292         }
 293
 294         if( !style_accept(scanner, '{') )
 295                 return FALSE;
 296
 297         while( g_scanner_peek_next_token(scanner) != '}') {
 298                 if( !style_accept_style_hint(scanner, current_tag) )
 299                         return FALSE;
 300         }
 301
 302         if( !style_accept(scanner, '}') )
 303                 return FALSE;
 304
 305         return TRUE;
 306 }
 307
 308 /* Internal function: parses a style hint */
 309 static gboolean
 310 style_accept_style_hint(GScanner *scanner, GtkTextTag *current_tag)
 311 {
 312         GTokenType token = g_scanner_get_next_token(scanner);
 313         GTokenValue value = g_scanner_cur_value(scanner);
 314         gchar *hint;
 315
 316         if(token != G_TOKEN_IDENTIFIER) {
 317                 g_scanner_error(scanner, "CSS Error: style hint expected");
 318                 return FALSE;
 319         }
 320
 321         hint = g_strdup(value.v_identifier);
 322
 323         if( !style_accept(scanner, ':') )
 324                 return FALSE;
 325
 326         token = g_scanner_get_next_token(scanner);
 327         value = g_scanner_cur_value(scanner);
 328
 329         if( !strcmp(hint, "font-family") ) {
 330                 if(token != G_TOKEN_STRING) {
 331                         g_scanner_error(scanner, "CSS Error: string expected");
 332                         return FALSE;
 333                 }
 334                 g_object_set(current_tag, "family", value.v_string, "family-set", TRUE, NULL);
 335         }
 336         else if( !strcmp(hint, "font-weight") ) {
 337                 if(token != G_TOKEN_IDENTIFIER) {
 338                         g_scanner_error(scanner, "CSS Error: bold/normal expected");
 339                         return FALSE;
 340                 }
 341
 342                 if( !strcmp(value.v_identifier, "bold") )
 343                         g_object_set(current_tag, "weight", PANGO_WEIGHT_BOLD, "weight-set", TRUE, NULL);
 344                 else if( !strcmp(value.v_identifier, "normal") )
 345                         g_object_set(current_tag, "weight", PANGO_WEIGHT_NORMAL, "weight-set", TRUE, NULL);
 346                 else {
 347                         g_scanner_error(scanner, "CSS Error: bold/normal expected");
 348                         return FALSE;
 349                 }
 350         }
 351         else if( !strcmp(hint, "font-style") ) {
 352                 if(token != G_TOKEN_IDENTIFIER) {
 353                         g_scanner_error(scanner, "CSS Error: italic/normal expected");
 354                         return FALSE;
 355                 }
 356
 357                 if( !strcmp(value.v_identifier, "italic") )
 358                         g_object_set(current_tag, "style", PANGO_STYLE_ITALIC, "style-set", TRUE, NULL);
 359                 else if( !strcmp(value.v_identifier, "normal") )
 360                         g_object_set(current_tag, "style", PANGO_STYLE_NORMAL, "style-set", TRUE, NULL);
 361                 else {
 362                         g_scanner_error(scanner, "CSS Error: italic/normal expected");
 363                         return FALSE;
 364                 }
 365         }
 366         else if( !strcmp(hint, "font-size") ) {
 367                 if(token == G_TOKEN_INT)
 368                         g_object_set(current_tag, "size-points", (float)value.v_int, "size-set", TRUE, NULL);
 369                 else if(token == G_TOKEN_FLOAT)
 370                         g_object_set(current_tag, "size-points", value.v_float, "size-set", TRUE, NULL);
 371                 else {
 372                         g_scanner_error(scanner, "CSS Error: integer or float expected");
 373                         return FALSE;
 374                 }
 375         }
 376         else if( !strcmp(hint, "color") ) {
 377                 if(token != G_TOKEN_IDENTIFIER) {
 378                         g_scanner_error(scanner, "CSS Error: hex color expected");
 379                         return FALSE;
 380                 }
 381
 382                 g_object_set(current_tag, "foreground", value.v_identifier, "foreground-set", TRUE, NULL);
 383         }
 384         else if( !strcmp(hint, "background-color") ) {
 385                 if(token != G_TOKEN_IDENTIFIER) {
 386                         g_scanner_error(scanner, "CSS Error: hex color expected");
 387                         return FALSE;
 388                 }
 389                 g_object_set(current_tag, "background", value.v_identifier, "background-set", TRUE, NULL);
 390         }
 391         else if( !strcmp(hint, "text-align") ) {
 392                 if(token != G_TOKEN_IDENTIFIER) {
 393                         g_scanner_error(scanner, "CSS Error: left/right/center expected");
 394                         return FALSE;
 395                 }
 396
 397                 if( !strcmp(value.v_identifier, "left") )
 398                         g_object_set(current_tag, "justification", GTK_JUSTIFY_LEFT, "justification-set", TRUE, NULL);
 399                 else if( !strcmp(value.v_identifier, "right") )
 400                         g_object_set(current_tag, "justification", GTK_JUSTIFY_RIGHT, "justification-set", TRUE, NULL);
 401                 else if( !strcmp(value.v_identifier, "center") )
 402                         g_object_set(current_tag, "justification", GTK_JUSTIFY_CENTER, "justification-set", TRUE, NULL);
 403                 else {
 404                         g_scanner_error(scanner, "CSS Error: left/right/center expected");
 405                         return FALSE;
 406                 }
 407         }
 408         else if( !strcmp(hint, "margin-left") ) {
 409                 if(token != G_TOKEN_INT) {
 410                         g_scanner_error(scanner, "CSS Error: integer expected");
 411                         return FALSE;
 412                 }
 413                 g_object_set(current_tag, "left-margin", value.v_int, "left-margin-set", TRUE, NULL);
 414         }
 415         else if( !strcmp(hint, "margin-right") ) {
 416                 if(token != G_TOKEN_INT) {
 417                         g_scanner_error(scanner, "CSS Error: integer expected");
 418                         return FALSE;
 419                 }
 420                 g_object_set(current_tag, "right-margin", value.v_int, "right-margin-set", TRUE, NULL);
 421         }
 422         else if( !strcmp(hint, "margin-top") ) {
 423                 if(token != G_TOKEN_INT) {
 424                         g_scanner_error(scanner, "CSS Error: integer expected");
 425                         return FALSE;
 426                 }
 427                 g_object_set(current_tag, "pixels-above-lines", value.v_int, "pixels-above-lines-set", TRUE, NULL);
 428         }
 429         else if( !strcmp(hint, "margin-bottom") ) {
 430                 if(token != G_TOKEN_INT) {
 431                         g_scanner_error(scanner, "CSS Error: integer expected");
 432                         return FALSE;
 433                 }
 434                 g_object_set(current_tag, "pixels-below-lines", value.v_int, "pixels-below-lines-set", TRUE, NULL);
 435         }
 436
 437         else {
 438                 g_scanner_error(scanner, "CSS Error: invalid style hint %s", hint);
 439                 return FALSE;
 440         }
 441
 442         if( !style_accept(scanner, ';') )
 443                 return FALSE;
 444
 445         return TRUE;
 446 }
 447
 448 /* Internal function: parses a glk color to a #hex-value */
 449 static void
 450 color_format(glui32 val, gchar *buffer)
 451 {
 452         g_return_if_fail(buffer != NULL);
 453
 454         sprintf(buffer, "#%02X%02X%02X",
 455                 ((val & 0xff0000) >> 16),
 456                 ((val & 0x00ff00) >> 8),
 457                 (val & 0x0000ff)
 458         );
 459 }
 460
 461 /* Internal function: parses a GdkColor to a glk color */
 462 static glui32
 463 color_parse_gdk(GdkColor *color)
 464 {
 465         g_return_val_if_fail(color != NULL, 0);
 466         return (glui32) color->pixel;
 467 }
 468
 469 /* Internal function: changes a GTK tag to correspond with the given style. */
 470 static void
 471 apply_stylehint_to_tag(GtkTextTag *tag, glui32 hint, glsi32 val)
 472 {
 473         g_return_if_fail(tag != NULL);
 474
 475         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
 476         GObject *tag_object = G_OBJECT(tag);
 477         gint reverse_color = 0;
 478
 479         /* FIXME where should we keep track of this?
 480         g_object_get(tag, "reverse_color", &reverse_color, NULL);
 481         */
 482
 483         int i = 0;
 484         gchar color[20];
 485         switch(hint) {
 486         case stylehint_Indentation:
 487                 g_object_set(tag_object, "left-margin", 5*val, "left-margin-set", TRUE, NULL);
 488                 g_object_set(tag_object, "right-margin", 5*val, "right-margin-set", TRUE, NULL);
 489                 break;
 490
 491         case stylehint_ParaIndentation:
 492                 g_object_set(tag_object, "indent", 5*val, "indent-set", TRUE, NULL);
 493                 break;
 494
 495         case stylehint_Justification:
 496                 switch(val) {
 497                         case stylehint_just_LeftFlush:  i = GTK_JUSTIFY_LEFT; break;
 498                         case stylehint_just_LeftRight:  i = GTK_JUSTIFY_FILL; break;
 499                         case stylehint_just_Centered:   i = GTK_JUSTIFY_CENTER; break;
 500                         case stylehint_just_RightFlush: i = GTK_JUSTIFY_RIGHT; break;
 501                         default:
 502                                 WARNING("Unknown justification");
 503                                 i = GTK_JUSTIFY_LEFT;
 504                 }
 505                 g_object_set(tag_object, "justification", i, "justification-set", TRUE, NULL);
 506                 break;
 507
 508         case stylehint_Weight:
 509                 switch(val) {
 510                         case -1: i = PANGO_WEIGHT_LIGHT; break;
 511                         case  0: i = PANGO_WEIGHT_NORMAL; break;
 512                         case  1: i = PANGO_WEIGHT_BOLD; break;
 513                         default: WARNING("Unknown font weight");
 514                 }
 515                 g_object_set(tag_object, "weight", i, "weight-set", TRUE, NULL);
 516                 break;
 517
 518         case stylehint_Size:
 519                 g_object_set(tag_object, "size", 14+(2*val), "size-set", TRUE, NULL);
 520                 break;
 521
 522         case stylehint_Oblique:
 523                 g_object_set(tag_object, "style", val ? PANGO_STYLE_ITALIC : PANGO_STYLE_NORMAL, "style-set", TRUE, NULL);
 524                 break;
 525
 526         case stylehint_Proportional:
 527                 g_object_set(tag_object, "font-desc", val ? glk_data->default_font_desc : glk_data->monospace_font_desc, NULL);
 528                 break;
 529
 530         case stylehint_TextColor:
 531                 color_format(val, color);
 532
 533                 if(!reverse_color)
 534                         g_object_set(tag_object, "foreground", color, "foreground-set", TRUE, NULL);
 535                 else
 536                         g_object_set(tag_object, "background", color, "background-set", TRUE, NULL);
 537
 538                 break;
 539
 540         case stylehint_BackColor:
 541                 color_format(val, color);
 542
 543                 if(!reverse_color)
 544                         g_object_set(tag_object, "background", color, "background-set", TRUE, NULL);
 545                 else
 546                         g_object_set(tag_object, "foreground", color, "background-set", TRUE, NULL);
 547
 548                 break;
 549
 550         case stylehint_ReverseColor:
 551                 if(reverse_color != val) {
 552                         /* Flip the fore- and background colors */
 553                         GdkColor* foreground_color;
 554                         GdkColor* background_color;
 555                         gint f_set, b_set = 0;
 556                         g_object_get(tag_object, "foreground-set", &f_set, "background-set", &b_set, NULL);
 557
 558                         if(f_set)
 559                                 g_object_get(tag_object, "foreground-gdk", &foreground_color, NULL);
 560                         if(b_set)
 561                                 g_object_get(tag_object, "background-gdk", &background_color, NULL);
 562
 563                         if(b_set)
 564                                 g_object_set(tag_object, "foreground-gdk", background_color, NULL);
 565                         else
 566                                 g_object_set(tag_object, "foreground", "#ffffff", NULL);
 567
 568                         if(f_set)
 569                                 g_object_set(tag_object, "background-gdk", foreground_color, NULL);
 570                         else
 571                                 g_object_set(tag_object, "background", "#000000", NULL);
 572                 }
 573                 break;
 574
 575         default:
 576                 WARNING("Unknown style hint");
 577         }
 578 }
 579 /*Internal function: queries a text tag for the value of a given style hint */
 580 static gint
 581 query_tag(GtkTextTag *tag, glui32 hint)
 582 {
 583         gint intval;
 584         GObject *objval;
 585         GdkColor *colval;
 586
 587         g_return_val_if_fail(tag != NULL, 0);
 588
 589         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
 590
 591         switch(hint) {
 592         case stylehint_Indentation:
 593                 g_object_get(tag, "left_margin", &intval, NULL);
 594                 return intval/5;
 595                 break;
 596
 597         case stylehint_ParaIndentation:
 598                 g_object_get(tag, "indent", &intval, NULL);
 599                 return intval/5;
 600                 break;
 601
 602         case stylehint_Justification:
 603                 g_object_get(tag, "justification", &intval, NULL);
 604                 switch(intval) {
 605                         case GTK_JUSTIFY_LEFT: return stylehint_just_LeftFlush; break;
 606                         case GTK_JUSTIFY_FILL: return stylehint_just_LeftRight; break;
 607                         case GTK_JUSTIFY_CENTER: return stylehint_just_Centered; break;
 608                         case GTK_JUSTIFY_RIGHT: return stylehint_just_RightFlush; break;
 609                         default:
 610                                 WARNING("Unknown justification");
 611                                 return stylehint_just_LeftFlush;
 612                 }
 613                 break;
 614
 615         case stylehint_Weight:
 616                 g_object_get(tag, "weight", &intval, NULL);
 617                 switch(intval) {
 618                         case PANGO_WEIGHT_LIGHT: return -1; break;
 619                         case PANGO_WEIGHT_NORMAL: return 0; break;
 620                         case PANGO_WEIGHT_BOLD: return 1; break;
 621                         default: WARNING("Unknown font weight"); return 0;
 622                 }
 623                 break;
 624
 625         case stylehint_Size:
 626                 g_object_get(tag, "size", &intval, NULL);
 627                 return (intval/2)-14;
 628                 break;
 629
 630         case stylehint_Oblique:
 631                 g_object_get(tag, "style", &intval , NULL);
 632                 return intval == PANGO_STYLE_ITALIC ? 1 : 0;
 633                 break;
 634
 635         case stylehint_Proportional:
 636                 g_object_get(tag, "font-desc", &objval, NULL);
 637                 return objval == (GObject *)glk_data->monospace_font_desc ? 0 : 1;
 638                 break;
 639
 640         case stylehint_TextColor:
 641                 g_object_get(tag, "foreground-gdk", &colval, NULL);
 642                 return color_parse_gdk(colval);
 643                 break;
 644
 645         case stylehint_BackColor:
 646                 g_object_get(tag, "background-gdk", &colval, NULL);
 647                 return color_parse_gdk(colval);
 648                 break;
 649
 650         case stylehint_ReverseColor:
 651                 /* FIXME: implement this */
 652                 return 0;
 653                 break;
 654
 655         default:
 656                 WARNING("Unknown style hint");
 657         }
 658
 659         return 0;
 660 }
 661
 662 /**
 663  * glk_stylehint_set:
 664  * @wintype: The window type to set a style hint on, or %wintype_AllTypes.
 665  * @styl: The style to set a hint for.
 666  * @hint: The type of style hint, one of the <code>stylehint_</code> constants.
 667  * @val: The style hint. The meaning of this depends on @hint.
 668  *
 669  * Sets a hint about the appearance of one style for a particular type of
 670  * window. You can also set wintype to %wintype_AllTypes, which sets a hint for
 671  * all types of window.
 672  * <note><para>
 673  *  There is no equivalent constant to set a hint for all styles of a single
 674  *  window type.
 675  * </para></note>
 676  */
 677 void
 678 glk_stylehint_set(glui32 wintype, glui32 styl, glui32 hint, glsi32 val)
 679 {
 680         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
 681
 682         if( G_UNLIKELY(!glk_data->style_initialized) ) {
 683                 style_init();
 684         }
 685
 686         GtkTextTag *to_change;
 687         if(wintype == wintype_TextBuffer || wintype == wintype_AllTypes) {
 688                 to_change = g_hash_table_lookup( glk_data->current_styles->text_buffer, get_tag_name(styl) );
 689                 apply_stylehint_to_tag(to_change, hint, val);
 690         }
 691
 692         if(wintype == wintype_TextGrid || wintype == wintype_AllTypes) {
 693                 to_change = g_hash_table_lookup( glk_data->current_styles->text_grid, get_tag_name(styl) );
 694                 apply_stylehint_to_tag(to_change, hint, val);
 695         }
 696 }
 697
 698 /**
 699  * glk_stylehint_clear:
 700  * @wintype: The window type to set a style hint on, or %wintype_AllTypes.
 701  * @styl: The style to set a hint for.
 702  * @hint: The type of style hint, one of the <code>stylehint_</code> constants.
 703  *
 704  * Resets a hint about the appearance of one style for a particular type of
 705  * window to it's default value. You can also set wintype to %wintype_AllTypes, which resets a hint for
 706  * all types of window.
 707  * <note><para>
 708  *  There is no equivalent constant to reset a hint for all styles of a single
 709  *  window type.
 710  * </para></note>
 711  */
 712 void
 713 glk_stylehint_clear(glui32 wintype, glui32 styl, glui32 hint)
 714 {
 715         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
 716         GtkTextTag *tag;
 717
 718         switch(wintype) {
 719         case wintype_TextBuffer:
 720                 tag = g_hash_table_lookup( glk_data->default_styles->text_buffer, get_tag_name(styl) );
 721                 glk_stylehint_set( wintype, styl, hint, query_tag(tag, hint) );
 722                 break;
 723         case wintype_TextGrid:
 724                 tag = g_hash_table_lookup( glk_data->default_styles->text_grid, get_tag_name(styl) );
 725                 glk_stylehint_set( wintype, styl, hint, query_tag(tag, hint) );
 726         default:
 727                 return;
 728         }
 729 }
 730
 731 /**
 732  * glk_style_distinguish:
 733  * @win: The window in which the styles are to be distinguished.
 734  * @styl1: The first style to be distinguished from the second style.
 735  * @styl2: The second styel to be distinguished from the first style.
 736  *
 737  * Returns: TRUE if the two styles are visually distinguishable in the given window.
 738  * If they are not, it returns FALSE.
 739  */
 740 glui32
 741 glk_style_distinguish(winid_t win, glui32 styl1, glui32 styl2)
 742 {
 743         return styl1 != styl2;
 744 }
 745
 746 /**
 747  * glk_style_measure:
 748  * @win: The window from which to take the style.
 749  * @styl: The style to perform the measurement on.
 750  * @hint: The stylehint to measure.
 751  * @result: Address to write the result to.
 752  *
 753  * This function can be used to query the current value of a particular style hint.
 754  * Returns: TRUE upon successul retrievel, otherwise FALSE.
 755  */
 756 glui32
 757 glk_style_measure(winid_t win, glui32 styl, glui32 hint, glui32 *result)
 758 {
 759         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
 760         GtkTextTag *tag;
 761
 762         switch(win->type) {
 763         case wintype_TextBuffer:
 764                 tag = g_hash_table_lookup( glk_data->current_styles->text_buffer, get_tag_name(styl) );
 765                 *result = query_tag(tag, hint);
 766                 break;
 767         case wintype_TextGrid:
 768                 tag = g_hash_table_lookup( glk_data->current_styles->text_grid, get_tag_name(styl) );
 769                 *result = query_tag(tag, hint);
 770         default:
 771                 return FALSE;
 772         }
 773
 774         return TRUE;
 775 }