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         /* Copy the reverse_color attribute, that was added manually */
 157         g_object_set_data( G_OBJECT(copy), "reverse_color", g_object_get_data(G_OBJECT(tag), "reverse_color") );
 158
 159         return copy;
 160 }
 161
 162 /* Internal function that reads the default styles from a CSS file */
 163 void
 164 style_init()
 165 {
 166         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
 167         GHashTable *default_text_grid_styles = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, g_object_unref);
 168         GHashTable *default_text_buffer_styles = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, g_object_unref);
 169         GHashTable *current_text_grid_styles = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, g_object_unref);
 170         GHashTable *current_text_buffer_styles = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, g_object_unref);
 171         GtkTextTag *tag;
 172
 173         /* Create the CSS file scanner */
 174         GScanner *scanner = g_scanner_new(NULL);
 175
 176         int f = open(glk_data->css_file, O_RDONLY);
 177         g_return_if_fail(f != -1);
 178         g_scanner_input_file(scanner, f);
 179         scanner->input_name = glk_data->css_file;
 180         scanner->config->cset_identifier_first = G_CSET_a_2_z G_CSET_A_2_Z "#";
 181         scanner->config->cset_identifier_nth = G_CSET_a_2_z G_CSET_A_2_Z "-_" G_CSET_DIGITS;
 182         scanner->config->symbol_2_token = TRUE;
 183         scanner->config->cpair_comment_single = NULL;
 184         scanner->config->scan_float = FALSE;
 185
 186         /* Initialise the default styles */
 187         g_hash_table_insert(default_text_grid_styles, "normal", gtk_text_tag_new("normal"));
 188
 189         tag = gtk_text_tag_new("emphasized");
 190         g_object_set(tag, "style", PANGO_STYLE_ITALIC, "style-set", TRUE, NULL);
 191         g_hash_table_insert(default_text_grid_styles, "emphasized", tag);
 192
 193         tag = gtk_text_tag_new("preformatted");
 194         g_object_set(tag, "font-desc", glk_data->monospace_font_desc, NULL);
 195         g_hash_table_insert(default_text_grid_styles, "preformatted", tag);
 196
 197         tag = gtk_text_tag_new("header");
 198         g_object_set(tag, "size-points", 18.0, "weight", PANGO_WEIGHT_BOLD, NULL);
 199         g_hash_table_insert(default_text_grid_styles, "header", tag);
 200
 201         tag = gtk_text_tag_new("subheader");
 202         g_object_set(tag, "size-points", 14.0, "weight", PANGO_WEIGHT_BOLD, NULL);
 203         g_hash_table_insert(default_text_grid_styles, "subheader", tag);
 204
 205         tag = gtk_text_tag_new("alert");
 206         g_object_set(tag, "foreground", "#aa0000", "weight", PANGO_WEIGHT_BOLD, NULL);
 207         g_hash_table_insert(default_text_grid_styles, "alert", tag);
 208
 209         tag = gtk_text_tag_new("note");
 210         g_object_set(tag, "foreground", "#aaaa00", "weight", PANGO_WEIGHT_BOLD, NULL);
 211         g_hash_table_insert(default_text_grid_styles, "note", tag);
 212
 213         tag = gtk_text_tag_new("block-quote");
 214         g_object_set(tag, "justification", GTK_JUSTIFY_CENTER, "style", PANGO_STYLE_ITALIC, NULL);
 215         g_hash_table_insert(default_text_grid_styles, "block-quote", tag);
 216
 217         g_hash_table_insert(default_text_grid_styles, "input", gtk_text_tag_new("input"));
 218         g_hash_table_insert(default_text_grid_styles, "user1", gtk_text_tag_new("user1"));
 219         g_hash_table_insert(default_text_grid_styles, "user2", gtk_text_tag_new("user2"));
 220
 221         g_hash_table_foreach(default_text_grid_styles, style_table_copy, default_text_buffer_styles);
 222         glk_data->default_styles->text_grid = default_text_grid_styles;
 223         glk_data->default_styles->text_buffer = default_text_buffer_styles;
 224
 225         /* Run the scanner over the CSS file, overriding defaults */
 226         while( g_scanner_peek_next_token(scanner) != G_TOKEN_EOF) {
 227                 if( !style_accept_style_selector(scanner) )
 228                         break;
 229         }
 230
 231         /* Set the current style to a copy of the default style */
 232         g_hash_table_foreach(default_text_grid_styles, style_table_copy, current_text_grid_styles);
 233         g_hash_table_foreach(default_text_buffer_styles, style_table_copy, current_text_buffer_styles);
 234         glk_data->current_styles->text_grid = current_text_grid_styles;
 235         glk_data->current_styles->text_buffer = current_text_buffer_styles;
 236
 237         g_scanner_destroy(scanner);
 238
 239         glk_data->style_initialized = TRUE;
 240 }
 241
 242 /* Internal function: parses a token */
 243 static gboolean
 244 style_accept(GScanner *scanner, GTokenType token)
 245 {
 246         GTokenType next = g_scanner_get_next_token(scanner);
 247         if(next != token ) {
 248                 g_scanner_unexp_token(scanner, token, NULL, NULL, NULL, "CSS Error", 1);
 249                 return FALSE;
 250         } else {
 251                 return TRUE;
 252         }
 253 }
 254
 255 /* Internal function: parses a style selector */
 256 static gboolean
 257 style_accept_style_selector(GScanner *scanner)
 258 {
 259         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
 260
 261         GtkTextTag *current_tag;
 262         gchar *field;
 263         GTokenType token = g_scanner_get_next_token(scanner);
 264         GTokenValue value = g_scanner_cur_value(scanner);
 265
 266         if(
 267                 token != G_TOKEN_IDENTIFIER ||
 268                 ( strcmp(value.v_identifier, "buffer") && strcmp(value.v_identifier, "grid") )
 269         ) {
 270                 g_scanner_error(scanner, "CSS Error: buffer/grid expected");
 271                 return FALSE;
 272         }
 273
 274         field = g_strdup(value.v_identifier);
 275
 276         if( !style_accept(scanner, '.') )
 277                 return FALSE;
 278
 279         token = g_scanner_get_next_token(scanner);
 280         value = g_scanner_cur_value(scanner);
 281
 282         if(token != G_TOKEN_IDENTIFIER) {
 283                 g_scanner_error(scanner, "CSS Error: style selector expected");
 284                 return FALSE;
 285         }
 286
 287         if( !strcmp(field, "buffer") )
 288                 current_tag = g_hash_table_lookup(glk_data->default_styles->text_buffer, value.v_identifier);
 289         else
 290                 current_tag = g_hash_table_lookup(glk_data->default_styles->text_grid, value.v_identifier);
 291
 292         if(current_tag == NULL) {
 293                 g_scanner_error(scanner, "CSS Error: invalid style identifier");
 294                 return FALSE;
 295         }
 296
 297         if( !style_accept(scanner, '{') )
 298                 return FALSE;
 299
 300         while( g_scanner_peek_next_token(scanner) != '}') {
 301                 if( !style_accept_style_hint(scanner, current_tag) )
 302                         return FALSE;
 303         }
 304
 305         if( !style_accept(scanner, '}') )
 306                 return FALSE;
 307
 308         return TRUE;
 309 }
 310
 311 /* Internal function: parses a style hint */
 312 static gboolean
 313 style_accept_style_hint(GScanner *scanner, GtkTextTag *current_tag)
 314 {
 315         GTokenType token = g_scanner_get_next_token(scanner);
 316         GTokenValue value = g_scanner_cur_value(scanner);
 317         gchar *hint;
 318
 319         if(token != G_TOKEN_IDENTIFIER) {
 320                 g_scanner_error(scanner, "CSS Error: style hint expected");
 321                 return FALSE;
 322         }
 323
 324         hint = g_strdup(value.v_identifier);
 325
 326         if( !style_accept(scanner, ':') )
 327                 return FALSE;
 328
 329         token = g_scanner_get_next_token(scanner);
 330         value = g_scanner_cur_value(scanner);
 331
 332         if( !strcmp(hint, "font-family") ) {
 333                 if(token != G_TOKEN_STRING) {
 334                         g_scanner_error(scanner, "CSS Error: string expected");
 335                         return FALSE;
 336                 }
 337                 g_object_set(current_tag, "family", value.v_string, "family-set", TRUE, NULL);
 338         }
 339         else if( !strcmp(hint, "font-weight") ) {
 340                 if(token != G_TOKEN_IDENTIFIER) {
 341                         g_scanner_error(scanner, "CSS Error: bold/normal expected");
 342                         return FALSE;
 343                 }
 344
 345                 if( !strcmp(value.v_identifier, "bold") )
 346                         g_object_set(current_tag, "weight", PANGO_WEIGHT_BOLD, "weight-set", TRUE, NULL);
 347                 else if( !strcmp(value.v_identifier, "normal") )
 348                         g_object_set(current_tag, "weight", PANGO_WEIGHT_NORMAL, "weight-set", TRUE, NULL);
 349                 else {
 350                         g_scanner_error(scanner, "CSS Error: bold/normal expected");
 351                         return FALSE;
 352                 }
 353         }
 354         else if( !strcmp(hint, "font-style") ) {
 355                 if(token != G_TOKEN_IDENTIFIER) {
 356                         g_scanner_error(scanner, "CSS Error: italic/normal expected");
 357                         return FALSE;
 358                 }
 359
 360                 if( !strcmp(value.v_identifier, "italic") )
 361                         g_object_set(current_tag, "style", PANGO_STYLE_ITALIC, "style-set", TRUE, NULL);
 362                 else if( !strcmp(value.v_identifier, "normal") )
 363                         g_object_set(current_tag, "style", PANGO_STYLE_NORMAL, "style-set", TRUE, NULL);
 364                 else {
 365                         g_scanner_error(scanner, "CSS Error: italic/normal expected");
 366                         return FALSE;
 367                 }
 368         }
 369         else if( !strcmp(hint, "font-size") ) {
 370                 if(token == G_TOKEN_INT)
 371                         g_object_set(current_tag, "size-points", (float)value.v_int, "size-set", TRUE, NULL);
 372                 else if(token == G_TOKEN_FLOAT)
 373                         g_object_set(current_tag, "size-points", value.v_float, "size-set", TRUE, NULL);
 374                 else {
 375                         g_scanner_error(scanner, "CSS Error: integer or float expected");
 376                         return FALSE;
 377                 }
 378         }
 379         else if( !strcmp(hint, "color") ) {
 380                 if(token != G_TOKEN_IDENTIFIER) {
 381                         g_scanner_error(scanner, "CSS Error: hex color expected");
 382                         return FALSE;
 383                 }
 384
 385                 g_object_set(current_tag, "foreground", value.v_identifier, "foreground-set", TRUE, NULL);
 386         }
 387         else if( !strcmp(hint, "background-color") ) {
 388                 if(token != G_TOKEN_IDENTIFIER) {
 389                         g_scanner_error(scanner, "CSS Error: hex color expected");
 390                         return FALSE;
 391                 }
 392                 g_object_set(current_tag, "background", value.v_identifier, "background-set", TRUE, NULL);
 393         }
 394         else if( !strcmp(hint, "text-align") ) {
 395                 if(token != G_TOKEN_IDENTIFIER) {
 396                         g_scanner_error(scanner, "CSS Error: left/right/center expected");
 397                         return FALSE;
 398                 }
 399
 400                 if( !strcmp(value.v_identifier, "left") )
 401                         g_object_set(current_tag, "justification", GTK_JUSTIFY_LEFT, "justification-set", TRUE, NULL);
 402                 else if( !strcmp(value.v_identifier, "right") )
 403                         g_object_set(current_tag, "justification", GTK_JUSTIFY_RIGHT, "justification-set", TRUE, NULL);
 404                 else if( !strcmp(value.v_identifier, "center") )
 405                         g_object_set(current_tag, "justification", GTK_JUSTIFY_CENTER, "justification-set", TRUE, NULL);
 406                 else {
 407                         g_scanner_error(scanner, "CSS Error: left/right/center expected");
 408                         return FALSE;
 409                 }
 410         }
 411         else if( !strcmp(hint, "margin-left") ) {
 412                 if(token != G_TOKEN_INT) {
 413                         g_scanner_error(scanner, "CSS Error: integer expected");
 414                         return FALSE;
 415                 }
 416                 g_object_set(current_tag, "left-margin", value.v_int, "left-margin-set", TRUE, NULL);
 417         }
 418         else if( !strcmp(hint, "margin-right") ) {
 419                 if(token != G_TOKEN_INT) {
 420                         g_scanner_error(scanner, "CSS Error: integer expected");
 421                         return FALSE;
 422                 }
 423                 g_object_set(current_tag, "right-margin", value.v_int, "right-margin-set", TRUE, NULL);
 424         }
 425         else if( !strcmp(hint, "margin-top") ) {
 426                 if(token != G_TOKEN_INT) {
 427                         g_scanner_error(scanner, "CSS Error: integer expected");
 428                         return FALSE;
 429                 }
 430                 g_object_set(current_tag, "pixels-above-lines", value.v_int, "pixels-above-lines-set", TRUE, NULL);
 431         }
 432         else if( !strcmp(hint, "margin-bottom") ) {
 433                 if(token != G_TOKEN_INT) {
 434                         g_scanner_error(scanner, "CSS Error: integer expected");
 435                         return FALSE;
 436                 }
 437                 g_object_set(current_tag, "pixels-below-lines", value.v_int, "pixels-below-lines-set", TRUE, NULL);
 438         }
 439
 440         else {
 441                 g_scanner_error(scanner, "CSS Error: invalid style hint %s", hint);
 442                 return FALSE;
 443         }
 444
 445         if( !style_accept(scanner, ';') )
 446                 return FALSE;
 447
 448         return TRUE;
 449 }
 450
 451 /* Internal function: parses a glk color to a #hex-value */
 452 static void
 453 color_format(glui32 val, gchar *buffer)
 454 {
 455         g_return_if_fail(buffer != NULL);
 456
 457         sprintf(buffer, "#%02X%02X%02X",
 458                 ((val & 0xff0000) >> 16),
 459                 ((val & 0x00ff00) >> 8),
 460                 (val & 0x0000ff)
 461         );
 462 }
 463
 464 /* Internal function: parses a GdkColor to a glk color */
 465 static glui32
 466 color_parse_gdk(GdkColor *color)
 467 {
 468         g_return_val_if_fail(color != NULL, 0);
 469         return (glui32) color->pixel;
 470 }
 471
 472 /* Internal function: changes a GTK tag to correspond with the given style. */
 473 static void
 474 apply_stylehint_to_tag(GtkTextTag *tag, glui32 hint, glsi32 val)
 475 {
 476         g_return_if_fail(tag != NULL);
 477
 478         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
 479         GObject *tag_object = G_OBJECT(tag);
 480
 481         gint reverse_color = GPOINTER_TO_INT( g_object_get_data(tag_object, "reverse-color") );
 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                         g_object_set_data( tag_object, "reverse-color", GINT_TO_POINTER(val != 0) );
 574                 }
 575                 break;
 576
 577         default:
 578                 WARNING("Unknown style hint");
 579         }
 580 }
 581 /*Internal function: queries a text tag for the value of a given style hint */
 582 static gint
 583 query_tag(GtkTextTag *tag, glui32 hint)
 584 {
 585         gint intval;
 586         GObject *objval;
 587         GdkColor *colval;
 588
 589         g_return_val_if_fail(tag != NULL, 0);
 590
 591         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
 592
 593         switch(hint) {
 594         case stylehint_Indentation:
 595                 g_object_get(tag, "left_margin", &intval, NULL);
 596                 return intval/5;
 597                 break;
 598
 599         case stylehint_ParaIndentation:
 600                 g_object_get(tag, "indent", &intval, NULL);
 601                 return intval/5;
 602                 break;
 603
 604         case stylehint_Justification:
 605                 g_object_get(tag, "justification", &intval, NULL);
 606                 switch(intval) {
 607                         case GTK_JUSTIFY_LEFT: return stylehint_just_LeftFlush; break;
 608                         case GTK_JUSTIFY_FILL: return stylehint_just_LeftRight; break;
 609                         case GTK_JUSTIFY_CENTER: return stylehint_just_Centered; break;
 610                         case GTK_JUSTIFY_RIGHT: return stylehint_just_RightFlush; break;
 611                         default:
 612                                 WARNING("Unknown justification");
 613                                 return stylehint_just_LeftFlush;
 614                 }
 615                 break;
 616
 617         case stylehint_Weight:
 618                 g_object_get(tag, "weight", &intval, NULL);
 619                 switch(intval) {
 620                         case PANGO_WEIGHT_LIGHT: return -1; break;
 621                         case PANGO_WEIGHT_NORMAL: return 0; break;
 622                         case PANGO_WEIGHT_BOLD: return 1; break;
 623                         default: WARNING("Unknown font weight"); return 0;
 624                 }
 625                 break;
 626
 627         case stylehint_Size:
 628                 g_object_get(tag, "size", &intval, NULL);
 629                 return (intval/2)-14;
 630                 break;
 631
 632         case stylehint_Oblique:
 633                 g_object_get(tag, "style", &intval , NULL);
 634                 return intval == PANGO_STYLE_ITALIC ? 1 : 0;
 635                 break;
 636
 637         case stylehint_Proportional:
 638                 g_object_get(tag, "font-desc", &objval, NULL);
 639                 return objval == (GObject *)glk_data->monospace_font_desc ? 0 : 1;
 640                 break;
 641
 642         case stylehint_TextColor:
 643                 g_object_get(tag, "foreground-gdk", &colval, NULL);
 644                 return color_parse_gdk(colval);
 645                 break;
 646
 647         case stylehint_BackColor:
 648                 g_object_get(tag, "background-gdk", &colval, NULL);
 649                 return color_parse_gdk(colval);
 650                 break;
 651
 652         case stylehint_ReverseColor:
 653                 return GPOINTER_TO_INT( g_object_get_data(G_OBJECT(tag), "reverse_color") );
 654                 break;
 655
 656         default:
 657                 WARNING("Unknown style hint");
 658         }
 659
 660         return 0;
 661 }
 662
 663 /**
 664  * glk_stylehint_set:
 665  * @wintype: The window type to set a style hint on, or %wintype_AllTypes.
 666  * @styl: The style to set a hint for.
 667  * @hint: The type of style hint, one of the <code>stylehint_</code> constants.
 668  * @val: The style hint. The meaning of this depends on @hint.
 669  *
 670  * Sets a hint about the appearance of one style for a particular type of
 671  * window. You can also set wintype to %wintype_AllTypes, which sets a hint for
 672  * all types of window.
 673  * <note><para>
 674  *  There is no equivalent constant to set a hint for all styles of a single
 675  *  window type.
 676  * </para></note>
 677  */
 678 void
 679 glk_stylehint_set(glui32 wintype, glui32 styl, glui32 hint, glsi32 val)
 680 {
 681         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
 682
 683         if( G_UNLIKELY(!glk_data->style_initialized) ) {
 684                 style_init();
 685         }
 686
 687         GtkTextTag *to_change;
 688         if(wintype == wintype_TextBuffer || wintype == wintype_AllTypes) {
 689                 to_change = g_hash_table_lookup( glk_data->current_styles->text_buffer, get_tag_name(styl) );
 690                 apply_stylehint_to_tag(to_change, hint, val);
 691         }
 692
 693         if(wintype == wintype_TextGrid || wintype == wintype_AllTypes) {
 694                 to_change = g_hash_table_lookup( glk_data->current_styles->text_grid, get_tag_name(styl) );
 695                 apply_stylehint_to_tag(to_change, hint, val);
 696         }
 697 }
 698
 699 /**
 700  * glk_stylehint_clear:
 701  * @wintype: The window type to set a style hint on, or %wintype_AllTypes.
 702  * @styl: The style to set a hint for.
 703  * @hint: The type of style hint, one of the <code>stylehint_</code> constants.
 704  *
 705  * Resets a hint about the appearance of one style for a particular type of
 706  * window to it's default value. You can also set wintype to %wintype_AllTypes, which resets a hint for
 707  * all types of window.
 708  * <note><para>
 709  *  There is no equivalent constant to reset a hint for all styles of a single
 710  *  window type.
 711  * </para></note>
 712  */
 713 void
 714 glk_stylehint_clear(glui32 wintype, glui32 styl, glui32 hint)
 715 {
 716         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
 717         GtkTextTag *tag;
 718
 719         switch(wintype) {
 720         case wintype_TextBuffer:
 721                 tag = g_hash_table_lookup( glk_data->default_styles->text_buffer, get_tag_name(styl) );
 722                 glk_stylehint_set( wintype, styl, hint, query_tag(tag, hint) );
 723                 break;
 724         case wintype_TextGrid:
 725                 tag = g_hash_table_lookup( glk_data->default_styles->text_grid, get_tag_name(styl) );
 726                 glk_stylehint_set( wintype, styl, hint, query_tag(tag, hint) );
 727         default:
 728                 return;
 729         }
 730 }
 731
 732 /**
 733  * glk_style_distinguish:
 734  * @win: The window in which the styles are to be distinguished.
 735  * @styl1: The first style to be distinguished from the second style.
 736  * @styl2: The second styel to be distinguished from the first style.
 737  *
 738  * Returns: TRUE if the two styles are visually distinguishable in the given window.
 739  * If they are not, it returns FALSE.
 740  */
 741 glui32
 742 glk_style_distinguish(winid_t win, glui32 styl1, glui32 styl2)
 743 {
 744         return styl1 != styl2;
 745 }
 746
 747 /**
 748  * glk_style_measure:
 749  * @win: The window from which to take the style.
 750  * @styl: The style to perform the measurement on.
 751  * @hint: The stylehint to measure.
 752  * @result: Address to write the result to.
 753  *
 754  * This function can be used to query the current value of a particular style hint.
 755  * Returns: TRUE upon successul retrievel, otherwise FALSE.
 756  */
 757 glui32
 758 glk_style_measure(winid_t win, glui32 styl, glui32 hint, glui32 *result)
 759 {
 760         ChimaraGlkPrivate *glk_data = g_private_get(glk_data_key);
 761         GtkTextTag *tag;
 762
 763         switch(win->type) {
 764         case wintype_TextBuffer:
 765                 tag = g_hash_table_lookup( glk_data->current_styles->text_buffer, get_tag_name(styl) );
 766                 *result = query_tag(tag, hint);
 767                 break;
 768         case wintype_TextGrid:
 769                 tag = g_hash_table_lookup( glk_data->current_styles->text_grid, get_tag_name(styl) );
 770                 *result = query_tag(tag, hint);
 771         default:
 772                 return FALSE;
 773         }
 774
 775         return TRUE;
 776 }