test/screen-review-test.c

   1 /*
   2  * AT-SPI - Assistive Technology Service Provider Interface
   3  * (Gnome Accessibility Project; http://developer.gnome.org/projects/gap)
   4  *
   5  * Copyright 2001 Sun Microsystems Inc.
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Library General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Library General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Library General Public
  18  * License along with this library; if not, write to the
  19  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20  * Boston, MA 02111-1307, USA.
  21  */
  22
  23 #include <stdlib.h>
  24 #include "../cspi/spi-private.h"
  25
  26 #define CLIP_DEBUG
  27
  28 #define BOUNDS_CONTAIN_X(b, p)  (((p)>=(b)->x) && ((p)<=((b)->x + (b)->width))\
  29             && ((b)->width > 0) && ((b)->height > 0))
  30
  31 #define BOUNDS_CONTAIN_Y(b, p)  (((p)>=(b)->y) && ((p)<=((b)->y + (b)->height))\
  32             && ((b)->width > 0) && ((b)->height > 0))
  33
  34 #define CHUNK_BOUNDS_BEFORE_START(c, i) ((i) && ((c)->clip_bounds.x < \
  35                                          (i)->clip_bounds.x))
  36
  37 #define CHUNK_BOUNDS_END_BEFORE_START(c, i) ((i) && \
  38                                          (((c)->clip_bounds.x + \
  39                                          (c)->clip_bounds.width) < \
  40                                          (i)->clip_bounds.x))
  41
  42 #define CHUNK_BOUNDS_AFTER_END(c, i) ((i) && ((c)->clip_bounds.x >= \
  43                                        ((i)->clip_bounds.x + \
  44                                         (i)->clip_bounds.width)))
  45
  46 #define CHUNK_BOUNDS_SPANS_END(c, i) ((i) && (((c)->clip_bounds.x + \
  47                                               (c)->clip_bounds.width) >= \
  48                                        ((i)->clip_bounds.x + \
  49                                         (i)->clip_bounds.width)))
  50
  51 //#define CHUNK_BOUNDS_WITHIN(c, i)  ((i) && ((c)->clip_bounds.x >= \
  52 //                               (i)->text_bounds.x) && \
  53 //                               (((c)->clip_bounds.x + (c)->clip_bounds.width) \
  54 //                               <= ((i)->text_bounds.x + (i)->text_bounds.width)))
  55
  56 static void report_screen_review_line  (const AccessibleEvent *event, void *user_data);
  57
  58 static gint n_elements_traversed = 0;
  59 static AccessibleEventListener *mouseclick_listener;
  60
  61 typedef struct _BoundaryRect {
  62         long int x;
  63         long int y;
  64         long int width;
  65         long int height;
  66         AccessibleRole role; /* role of last clipping element */
  67         gboolean isClipped;
  68         gboolean isEmpty;
  69 } BoundaryRect;
  70
  71 typedef struct _TextChunk {
  72         char           *string;
  73         AccessibleText *source;
  74         int             start_offset;
  75         int             end_offset;
  76         BoundaryRect    clip_bounds;
  77         BoundaryRect    text_bounds;
  78         BoundaryRect    start_char_bounds;
  79         BoundaryRect    end_char_bounds;
  80 } TextChunk;
  81
  82 typedef struct _ScreenReviewBuffer { /* TODO: implement */
  83         GList *text_chunks;
  84 } ScreenReviewBuffer;
  85
  86 static gboolean isJava = FALSE;
  87
  88 int
  89 main (int argc, char **argv)
  90 {
  91   int i, j;
  92   int n_desktops;
  93   int n_apps;
  94   char *s;
  95   GTimer *timer;
  96   gdouble elapsed_time;
  97   Accessible *desktop;
  98   Accessible *application;
  99   const char *modules;
 100
 101   SPI_init ();
 102
 103   mouseclick_listener = SPI_createAccessibleEventListener (
 104           report_screen_review_line, NULL);
 105
 106   SPI_registerGlobalEventListener (mouseclick_listener,
 107                                    "Gtk:GtkWidget:button-press-event");
 108 #define JAVA_TEST_HACK
 109 #ifdef JAVA_TEST_HACK
 110   SPI_registerGlobalEventListener (mouseclick_listener,
 111                                    "object:text-caret-moved");
 112   isJava = TRUE;
 113 #endif
 114   SPI_event_main ();
 115
 116   putenv ("AT_BRIDGE_SHUTDOWN=1");
 117
 118   /*
 119    * TODO: Add a key event listener that calls test_exit, to
 120    * deregister and cleanup appropriately.
 121    */
 122
 123   return SPI_exit ();
 124 }
 125
 126 static inline gboolean
 127 bounds_contain_y (BoundaryRect *bounds, int y)
 128 {
 129         return (y > bounds->y && y <= (bounds->y + bounds->height)
 130                 && bounds->width && bounds->height);
 131 }
 132
 133
 134 static inline gboolean
 135 chunk_bounds_within (TextChunk *chunk, TextChunk *test_chunk)
 136 {
 137         int x1, x2, tx1, tx2;
 138         gboolean gtx1, ltx2;
 139
 140         x1 = chunk->clip_bounds.x;
 141         x2 = x1 + chunk->clip_bounds.width;
 142         tx1 = test_chunk->clip_bounds.x;
 143         tx2 = tx1 + test_chunk->clip_bounds.width;
 144         gtx1 = (chunk->clip_bounds.x >= test_chunk->clip_bounds.x);
 145         ltx2 = (chunk->clip_bounds.x + chunk->clip_bounds.width
 146                 <= test_chunk->clip_bounds.x + test_chunk->clip_bounds.width);
 147
 148 //      fprintf (stderr, "testing BOUNDS %d-%d WITHIN %d-%d: %s\n",
 149 //               x1, x2, tx1, tx2, ((gtx1 && ltx2) ? "T" : "F"));
 150
 151         return gtx1 && ltx2;
 152 }
 153
 154 #define CHUNK_BOUNDS_WITHIN(a, b) chunk_bounds_within(a, b)
 155
 156 static BoundaryRect **
 157 clip_bounds_clone (BoundaryRect *bounds[])
 158 {
 159         int i;
 160         BoundaryRect **bounds_clone;
 161         bounds_clone = (BoundaryRect **)
 162                 g_new0 (gpointer, SPI_LAYER_LAST_DEFINED);
 163         for (i = 0; i < SPI_LAYER_LAST_DEFINED; ++i) {
 164                 bounds_clone[i] = g_new0 (BoundaryRect, 1);
 165                 *bounds_clone[i] = *bounds[i];
 166         }
 167         return bounds_clone;
 168 }
 169
 170 static void
 171 boundary_clip (BoundaryRect *bounds, BoundaryRect *clipBounds)
 172 {
 173         int x2 = bounds->x + bounds->width;
 174         int y2 = bounds->y + bounds->height;
 175 #ifdef CLIP_DEBUG
 176         fprintf (stderr, "bclip %d-%d, %d-%d; ",
 177                  bounds->x, x2,
 178                  clipBounds->x, clipBounds->x+clipBounds->width);
 179 #endif
 180         bounds->x = MAX (bounds->x, clipBounds->x);
 181         bounds->y = MAX (bounds->y, clipBounds->y);
 182         x2 =  MIN (x2,  clipBounds->x + clipBounds->width);
 183         y2 =  MIN (y2, clipBounds->y + clipBounds->height);
 184         bounds->width = MAX (x2 - bounds->x, 0);
 185         bounds->height = MAX (y2 - bounds->y, 0);
 186         if (!bounds->width || !bounds->height)
 187                 bounds->isEmpty = TRUE;
 188 #ifdef CLIP_DEBUG
 189         fprintf (stderr, "%d-%d\n",
 190                  bounds->x, bounds->x+bounds->width);
 191 #endif
 192 }
 193
 194 static void
 195 boundary_xclip_head (BoundaryRect *bounds, BoundaryRect *clipBounds)
 196 {
 197         int x2;
 198         int cx2 = clipBounds->x + clipBounds->width;
 199         if (cx2 < bounds->x) return;
 200         x2 = bounds->x + bounds->width;
 201         if (cx2 < x2) bounds->x = cx2;
 202         bounds->width = MAX (0, x2 - cx2);
 203 }
 204
 205 static void
 206 boundary_xclip_tail (BoundaryRect *bounds, BoundaryRect *clipBounds)
 207 {
 208         int x2 = bounds->x + bounds->width;
 209         if (clipBounds->x > x2) return;
 210         bounds->width = MAX (0, clipBounds->x - bounds->x);
 211 }
 212
 213 static TextChunk*
 214 text_chunk_copy (TextChunk *chunk)
 215 {
 216         TextChunk *copy = g_new0 (TextChunk, 1);
 217         *copy = *chunk;
 218         if (chunk->string) copy->string = g_strdup (chunk->string);
 219         if (copy->source) AccessibleText_ref (copy->source);
 220         return copy;
 221 }
 222
 223 static void
 224 text_chunk_tail_clip (TextChunk *bottom, TextChunk *top)
 225 {
 226 #ifdef CLIP_DEBUG
 227         fprintf (stderr, "bottom %d-%d, top %d-%d;",
 228                  bottom->clip_bounds.x,
 229                  bottom->clip_bounds.x + bottom->clip_bounds.width,
 230                  top->clip_bounds.x,
 231                  top->clip_bounds.x + top->clip_bounds.width);
 232 #endif
 233         boundary_xclip_tail (&bottom->text_bounds, &top->clip_bounds);
 234         boundary_xclip_tail (&bottom->clip_bounds, &top->clip_bounds);
 235         bottom->text_bounds.isClipped = TRUE;
 236         bottom->clip_bounds.isClipped = TRUE;
 237 #ifdef CLIP_DEBUG
 238         fprintf (stderr, "result %d-%d\n",
 239                  bottom->clip_bounds.x,
 240                  bottom->clip_bounds.x + bottom->clip_bounds.width);
 241 #endif
 242 }
 243
 244 static void
 245 text_chunk_head_clip (TextChunk *bottom, TextChunk *top)
 246 {
 247 #ifdef CLIP_DEBUG
 248         fprintf (stderr, "bottom %d-%d, top %d-%d;",
 249                  bottom->clip_bounds.x,
 250                  bottom->clip_bounds.x + bottom->clip_bounds.width,
 251                  top->clip_bounds.x,
 252                  top->clip_bounds.x + top->clip_bounds.width);
 253 #endif
 254         boundary_xclip_head (&bottom->text_bounds, &top->clip_bounds);
 255         boundary_xclip_head (&bottom->clip_bounds, &top->clip_bounds);
 256         bottom->text_bounds.isClipped = TRUE;
 257         bottom->clip_bounds.isClipped = TRUE;
 258 #ifdef CLIP_DEBUG
 259         fprintf (stderr, "result %d-%d\n",
 260                  bottom->clip_bounds.x,
 261                  bottom->clip_bounds.x + bottom->clip_bounds.width);
 262 #endif
 263 }
 264
 265 static GList *
 266 text_chunk_split_insert (GList *chunk_list, GList *iter, TextChunk *chunk)
 267 {
 268         TextChunk *iter_chunk = iter->data;
 269         TextChunk *iter_copy = text_chunk_copy (iter_chunk);
 270         /* TODO: FIXME something is wrong here */
 271 #ifdef CLIP_DEBUG
 272         fprintf (stderr, "***clip insert of %s into %s\n", chunk->string,
 273                  iter_chunk->string);
 274 #endif
 275         chunk_list = g_list_insert_before (chunk_list, iter, iter_copy);
 276         text_chunk_tail_clip (iter_copy, chunk);
 277         chunk_list = g_list_insert_before (chunk_list, iter, chunk);
 278         text_chunk_head_clip (iter_chunk, chunk);
 279         return chunk_list;
 280 }
 281
 282 /* #define PRINT_CHUNK_DEBUG(a, b, c, d) print_chunk_debug(a, b, c, d) */
 283
 284 #define PRINT_CHUNK_DEBUG(a, b, c, d)
 285
 286 #ifdef PRINT_CHUNK_DEBUG
 287 static void
 288 print_chunk_debug (TextChunk *chunk, char *opname, GList *prev, GList *next)
 289 {
 290         fprintf (stderr, "%sing chunk %s between %s and %s; %d-%d\n",
 291                  opname,
 292                  chunk->string,
 293                  (prev ? ((TextChunk *) prev->data)->string : "<null>"),
 294                  (next ? ((TextChunk *) next->data)->string : "<null>"),
 295                  chunk->clip_bounds.x,
 296                  chunk->text_bounds.x + chunk->text_bounds.width);
 297 }
 298 #endif
 299
 300 static GList *
 301 text_chunk_list_head_clip (GList *text_chunk_list,
 302                            TextChunk *chunk,
 303                            GList *next)
 304 {
 305         GList *target, *iter = next, *prev;
 306         prev = iter->prev;
 307 //      if (chunk->string && strlen (chunk->string)) {
 308                 text_chunk_list =
 309                         g_list_insert_before (text_chunk_list, next, chunk);
 310 //      }
 311         while (iter) {
 312                 if (CHUNK_BOUNDS_SPANS_END (chunk, (TextChunk *)iter->data)) {
 313 #ifdef CLIP_DEBUG
 314                         fprintf (stderr, "deleting %s\n",
 315                                  ((TextChunk *)iter->data)->string);
 316 #endif
 317                         target = iter;
 318                         iter = iter->next;
 319                         text_chunk_list =
 320                                 g_list_delete_link (text_chunk_list, target);
 321                 } else {
 322                         if (!CHUNK_BOUNDS_END_BEFORE_START (chunk,
 323                                                       (TextChunk *)iter->data)) {
 324                                 text_chunk_head_clip ((TextChunk *)iter->data,
 325                                                       chunk);
 326                         }
 327                         if (prev &&
 328                             !CHUNK_BOUNDS_AFTER_END (
 329                                     chunk,
 330                                     (TextChunk *)prev->data)) {
 331                                 text_chunk_tail_clip (
 332                                         (TextChunk *)prev->data,
 333                                         chunk);
 334                         }
 335                         break;
 336                 }
 337         }
 338
 339         return text_chunk_list;
 340 }
 341
 342 static GList *
 343 text_chunk_list_clip_and_insert (GList *text_chunk_list,
 344                                  TextChunk *chunk,
 345                                  GList *prev,
 346                                  GList *next)
 347 {
 348 #ifdef CLIP_DEBUG
 349         fprintf (stderr, "clip-and-insert for %s, between %s and %s\n",
 350                  chunk->string,
 351                  (prev ? ((TextChunk *)prev->data)->string : "<null>"),
 352                  (next ? ((TextChunk *)next->data)->string : "<null>"));
 353 #endif
 354         /* cases: */
 355         if (!prev && !next) { /* first element in, no clip needed */
 356 //              if (chunk->string && strlen (chunk->string)) {
 357                         text_chunk_list =
 358                                 g_list_append (text_chunk_list, chunk);
 359                         PRINT_CHUNK_DEBUG (chunk, "append",
 360                                            prev,
 361                                            NULL);
 362 //              }
 363         } else { /* check for clip with prev */
 364                 /* if we split the prev */
 365                 if (prev &&
 366                     CHUNK_BOUNDS_WITHIN (chunk, (TextChunk *) prev->data)) {
 367                         text_chunk_list =
 368                                 text_chunk_split_insert (
 369                                         text_chunk_list,
 370                                         prev, chunk);
 371                 } else if (next) {
 372                     /* we split the 'next' element */
 373                     if (CHUNK_BOUNDS_WITHIN (chunk, (TextChunk *)next->data)) {
 374                             text_chunk_list =
 375                                     text_chunk_split_insert (text_chunk_list,
 376                                                              next, chunk);
 377                     } else {
 378                             /* do an insert +  head clip */
 379                             text_chunk_list =
 380                                     text_chunk_list_head_clip (
 381                                             text_chunk_list,
 382                                             chunk,
 383                                             next);
 384                     }
 385                 } else {
 386                         if (!CHUNK_BOUNDS_AFTER_END (chunk,
 387                                                      (TextChunk *) prev->data)) {
 388                                 text_chunk_tail_clip (prev->data, chunk);
 389                         }
 390 //                      if (chunk->string && strlen (chunk->string)) {
 391                                 text_chunk_list =
 392                                         g_list_append (text_chunk_list, chunk);
 393 //                      }
 394                 }
 395         }
 396         return text_chunk_list;
 397 }
 398
 399 static GList *
 400 text_chunk_list_insert_chunk (GList *text_chunk_list, TextChunk *chunk)
 401 {
 402         GList *iter = g_list_first (text_chunk_list);
 403         TextChunk *iter_chunk = NULL;
 404         do {
 405                 if (iter) iter_chunk = (TextChunk *) iter->data;
 406                 /* if we're ahead of the current element */
 407                 if (!iter) {
 408                         text_chunk_list =
 409                                 text_chunk_list_clip_and_insert (text_chunk_list,
 410                                                                  chunk,
 411                                                                  iter,
 412                                                                  NULL);
 413                         break;
 414                 } else if (CHUNK_BOUNDS_BEFORE_START (chunk, iter_chunk)) {
 415                         text_chunk_list =
 416                                 text_chunk_list_clip_and_insert (text_chunk_list,
 417                                                                  chunk,
 418                                                                  iter->prev,
 419                                                                  iter);
 420                         break;
 421                 } else if (!iter->next ) {
 422                         text_chunk_list =
 423                                 text_chunk_list_clip_and_insert (text_chunk_list,
 424                                                                  chunk,
 425                                                                  iter,
 426                                                                  NULL);
 427                         break;
 428                 }
 429                 if (iter) iter = iter->next;
 430         } while (iter);
 431         return text_chunk_list;
 432 }
 433
 434 static TextChunk *
 435 review_buffer_get_text_chunk (ScreenReviewBuffer *reviewBuffer,
 436                               Accessible *accessible, BoundaryRect *bounds,
 437                               int screen_x, int screen_y)
 438 {
 439         AccessibleText *text = NULL;
 440         AccessibleRole role;
 441         TextChunk *text_chunk;
 442         BoundaryRect start_char_bounds, end_char_bounds;
 443         char *s = NULL;
 444         int offset;
 445         long start, end;
 446         long x2, y2;
 447
 448         role = Accessible_getRole (accessible);
 449         text_chunk = g_new0 (TextChunk, 1);
 450         text_chunk->clip_bounds = *bounds;
 451         if (Accessible_isText (accessible)) {
 452                 text = Accessible_getText (accessible);
 453                 offset = AccessibleText_getOffsetAtPoint (text,
 454                                                           screen_x,
 455                                                           screen_y,
 456                                                           SPI_COORD_TYPE_SCREEN);
 457                 s = AccessibleText_getTextAtOffset (text, offset,
 458                                                     SPI_TEXT_BOUNDARY_LINE_START,
 459                                                     &start, &end);
 460                 if (end > start) {
 461                         AccessibleText_getCharacterExtents (
 462                                 text, start,
 463                                 &text_chunk->start_char_bounds.x,
 464                                 &text_chunk->start_char_bounds.y,
 465                                 &text_chunk->start_char_bounds.width,
 466                                 &text_chunk->start_char_bounds.height,
 467                                 SPI_COORD_TYPE_SCREEN);
 468 #ifdef CLIP_DEBUG
 469                         fprintf (stderr, "%s: start char (%d) x, width %d %d;",
 470                                  s,
 471                                  start,
 472                                  text_chunk->start_char_bounds.x,
 473                                  text_chunk->start_char_bounds.width);
 474 #endif
 475                         end--; /* XXX: bug workaround */
 476                         AccessibleText_getCharacterExtents (
 477                                 text, end--,
 478                                 &text_chunk->end_char_bounds.x,
 479                                 &text_chunk->end_char_bounds.y,
 480                                 &text_chunk->end_char_bounds.width,
 481                                 &text_chunk->end_char_bounds.height,
 482                                 SPI_COORD_TYPE_SCREEN);
 483 #ifdef CLIP_DEBUG
 484                         fprintf (stderr, "end char (%d) x, width %d %d\n",
 485                                  end,
 486                                  text_chunk->end_char_bounds.x,
 487                                  text_chunk->end_char_bounds.width);
 488 #endif
 489                 }
 490                 text_chunk->text_bounds.x = MIN (text_chunk->start_char_bounds.x,
 491                                                  text_chunk->end_char_bounds.x);
 492                 text_chunk->text_bounds.y = MIN (text_chunk->start_char_bounds.y,
 493                                                  text_chunk->end_char_bounds.y);
 494                 x2 = MAX (text_chunk->start_char_bounds.x +
 495                           text_chunk->start_char_bounds.width,
 496                           text_chunk->end_char_bounds.x +
 497                           text_chunk->end_char_bounds.width);
 498                 text_chunk->text_bounds.width = x2 - text_chunk->text_bounds.x;
 499                 y2 = MAX (text_chunk->start_char_bounds.y +
 500                           text_chunk->start_char_bounds.height,
 501                           text_chunk->end_char_bounds.y +
 502                           text_chunk->end_char_bounds.height);
 503                 text_chunk->text_bounds.height = y2 - text_chunk->text_bounds.y;
 504                 text_chunk->start_offset = start;
 505                 text_chunk->end_offset = end;
 506                 if ((role != SPI_ROLE_TABLE_CELL) /* XXX bug workaround */
 507                     && !bounds_contain_y (&text_chunk->text_bounds,
 508                                           screen_y)) {
 509                         s = NULL;
 510                 }
 511         } else {
 512                 if (role == SPI_ROLE_PUSH_BUTTON ||
 513                     role == SPI_ROLE_CHECK_BOX ||
 514                     role == SPI_ROLE_MENU ||
 515                     role == SPI_ROLE_MENU_ITEM) { /* don't like this
 516                                                      special casing :-( */
 517                         s = Accessible_getName (accessible);
 518                         /* use name instead */
 519                         text_chunk->text_bounds = text_chunk->clip_bounds;
 520                         text_chunk->start_offset = 0;
 521                         text_chunk->end_offset = strlen (s);
 522                 }
 523         }
 524         if (s && strlen (s)) {
 525                 if (s[strlen(s)-1] == '\n') s[strlen(s)-1] = ' ';
 526                 /* XXX: if last char is newline, aren't its bounds wrong now? */
 527                 text_chunk->string = s;
 528                 text_chunk->source = text;
 529                 if (text) AccessibleText_ref (text);
 530 #ifdef CLIP_DEBUG
 531                 fprintf (stderr, "%s, bounds %d-%d; clip %d-%d\n",
 532                          s,
 533                          text_chunk->text_bounds.x,
 534                          text_chunk->text_bounds.x+text_chunk->text_bounds.width,
 535                          text_chunk->clip_bounds.x,
 536                          text_chunk->clip_bounds.x+text_chunk->clip_bounds.width);
 537 #endif
 538         } else {
 539                 text_chunk->string = NULL;
 540                 text_chunk->source = NULL;
 541         }
 542         if (text) AccessibleText_unref (text);
 543         return text_chunk;
 544 }
 545
 546 static void
 547 debug_chunk_list (GList *iter)
 548 {
 549         TextChunk *chunk;
 550         while (iter) {
 551                 chunk = (TextChunk *)iter->data;
 552                 fprintf (stderr, "Chunk %s, clip %d-%d, text %d-%d\n",
 553                          chunk->string,
 554                          chunk->clip_bounds.x,
 555                          chunk->clip_bounds.x + chunk->clip_bounds.width,
 556                          chunk->text_bounds.x,
 557                          chunk->text_bounds.x + chunk->text_bounds.width);
 558                 iter = iter->next;
 559         }
 560 }
 561
 562 static void
 563 clip_into_buffers (Accessible *accessible,  BoundaryRect* parentClipBounds[],
 564                    ScreenReviewBuffer *reviewBuffers[],
 565                    int screen_x, int screen_y)
 566 {
 567         int n_children, child_n;
 568         Accessible *child;
 569         BoundaryRect bounds;
 570         BoundaryRect** clip_bounds;
 571         TextChunk *text_chunk;
 572         AccessibleComponent *component;
 573         int layer;
 574
 575         clip_bounds = clip_bounds_clone (parentClipBounds);
 576         if (Accessible_isComponent (accessible)) {
 577                 component = Accessible_getComponent (accessible);
 578                 layer = AccessibleComponent_getLayer (component);
 579                 bounds = *clip_bounds[layer];
 580                 if (!bounds.isEmpty || 1) {
 581                         AccessibleComponent_getExtents (component,
 582                                                         &bounds.x,
 583                                                         &bounds.y,
 584                                                         &bounds.width,
 585                                                         &bounds.height,
 586                                                         SPI_COORD_TYPE_SCREEN);
 587                         if (clip_bounds[layer])
 588                                 boundary_clip (&bounds, clip_bounds[layer]);
 589                         if (bounds_contain_y (&bounds, screen_y)) {
 590                                 text_chunk = review_buffer_get_text_chunk (
 591                                         reviewBuffers[layer], accessible, &bounds,
 592                                         screen_x, screen_y);
 593                                 reviewBuffers[layer]->text_chunks =
 594                                         text_chunk_list_insert_chunk (
 595                                                 reviewBuffers[layer]->text_chunks,
 596                                                 text_chunk);
 597                         } else {
 598                                 clip_bounds[layer]->isEmpty = TRUE;
 599                         }
 600                 }
 601                 Accessible_unref (component);
 602         }
 603         /*
 604          * we always descend into children in case they are in a higher layer
 605          * this can of course be optimized for the topmost layer...
 606          * but nobody uses that one! (SPI_LAYER_OVERLAY)
 607          */
 608         n_children = Accessible_getChildCount (accessible);
 609         for (child_n = 0; child_n < n_children; ++child_n) {
 610                 child = Accessible_getChildAtIndex (accessible, child_n);
 611                 clip_into_buffers (child, clip_bounds, reviewBuffers, screen_x, screen_y);
 612                 Accessible_unref (child);
 613         }
 614         /* TODO: free the parent clip bounds */
 615 }
 616
 617 static char*
 618 text_chunk_get_clipped_string (TextChunk *chunk)
 619 {
 620         char *s;
 621         int i;
 622         int len;
 623         gunichar c;
 624         GString *string = g_string_new ("");
 625         BoundaryRect char_bounds;
 626         if (!chunk->text_bounds.isClipped)
 627                 s = chunk->string;
 628         else if (chunk->source) {
 629                 len = chunk->end_offset - chunk->start_offset;
 630 #ifdef CLIP_DEBUG
 631                 fprintf (stderr, "clipping %s\n", chunk->string);
 632 #endif
 633                 for (i = 0; i < len; ++i) {
 634                         AccessibleText_getCharacterExtents (chunk->source,
 635                                                             i,
 636                                                             &char_bounds.x,
 637                                                             &char_bounds.y,
 638                                                             &char_bounds.width,
 639                                                             &char_bounds.height,
 640                                                             SPI_COORD_TYPE_SCREEN);
 641 #ifdef CHARACTER_CLIP_DEBUG
 642                         fprintf (stderr, "testing %d-%d against %d-%d\n",
 643                                  char_bounds.x, char_bounds.x+char_bounds.width,
 644                                  chunk->text_bounds.x,
 645                                  chunk->text_bounds.x + chunk->text_bounds.width);
 646 #endif
 647                         if (BOUNDS_CONTAIN_X (&chunk->text_bounds,
 648                                               char_bounds.x)) {
 649                                 c = AccessibleText_getCharacterAtOffset (
 650                                         chunk->source, i);
 651 #ifdef CLIP_DEBUG
 652                                 fprintf (stderr, "[%c]", c);
 653 #endif
 654                                 g_string_append_unichar (string, c);
 655                         }
 656                 }
 657                 s = string->str;
 658         } else { /* we're clipped, but don't implement AccessibleText :-( */
 659                 /* punt for now, maybe we can do betterc someday */
 660                 s = chunk->string;
 661         }
 662         g_string_free (string, FALSE);
 663         return s;
 664 }
 665
 666 static char*
 667 text_chunk_list_to_string (GList *iter)
 668 {
 669         char *s = "";
 670         char *string;
 671         TextChunk *chunk = NULL;
 672         while (iter) {
 673                 chunk = (TextChunk *)iter->data;
 674                 if (chunk /* && chunk->string */) {
 675                         string = text_chunk_get_clipped_string (chunk);
 676                         if (string)
 677                                 s = g_strconcat (s, "|", string, NULL);
 678                         else /* XXX test */
 679                                 s = g_strconcat (s, ":", NULL);
 680                 }
 681                 iter = iter->next;
 682         }
 683         s = g_strconcat (s, "|", NULL);
 684         return s;
 685 }
 686
 687 static char*
 688 review_buffer_composite (ScreenReviewBuffer *buffers[])
 689 {
 690         int i;
 691         GList *chunk_list, *iter;
 692         TextChunk *chunk;
 693         chunk_list = buffers[0]->text_chunks;
 694         for (i = 1; i < SPI_LAYER_LAST_DEFINED; ++i) {
 695                 iter = buffers[i]->text_chunks;
 696                 fprintf (stderr, "layer %d has %d chunks\n",
 697                          i, g_list_length (iter));
 698                 while (iter) {
 699                         chunk = (TextChunk *) iter->data;
 700                         if (chunk) {
 701                                 fprintf (stderr, "inserting chunk <%s>\n",
 702                                          chunk->string);
 703                                 chunk_list =
 704                                         text_chunk_list_insert_chunk (chunk_list,
 705                                                                       chunk);
 706                         }
 707                         iter = iter->next;
 708                 }
 709         }
 710         chunk_list = buffers[SPI_LAYER_WIDGET]->text_chunks;
 711         return text_chunk_list_to_string (chunk_list);
 712 }
 713
 714 static char *
 715 get_screen_review_line_at (int x, int y)
 716 {
 717   char *string;
 718   Accessible *desktop, *app, *toplevel, *child;
 719   AccessibleComponent *component;
 720   AccessibleStateSet *states;
 721   GList *toplevels = NULL, *actives = NULL, *iter;
 722   ScreenReviewBuffer* reviewBuffers[SPI_LAYER_LAST_DEFINED];
 723   BoundaryRect* clip_bounds[SPI_LAYER_LAST_DEFINED];
 724   BoundaryRect toplevel_bounds;
 725   int n_apps, n_toplevels, n_children, app_n, toplevel_n, child_n;
 726   GTimer *timer = g_timer_new ();
 727   int i;
 728
 729   for (i = 0; i < SPI_LAYER_LAST_DEFINED; ++i) {
 730           reviewBuffers[i] = g_new0 (ScreenReviewBuffer, 1);
 731           clip_bounds[i] = g_new0 (BoundaryRect, 1);
 732           clip_bounds[i]->isClipped = FALSE;
 733           clip_bounds[i]->isEmpty = FALSE;
 734   }
 735
 736   /* how do we decide which desktop ? */
 737   desktop = SPI_getDesktop (0);
 738
 739   /* for each app */
 740   n_apps = Accessible_getChildCount (desktop);
 741   for (app_n = 0; app_n < n_apps; ++app_n) {
 742           /* for each toplevel in app */
 743           app =  Accessible_getChildAtIndex (desktop, app_n);
 744           n_toplevels = Accessible_getChildCount (app);
 745           for (toplevel_n = 0; toplevel_n < n_toplevels; ++toplevel_n) {
 746                   Accessible *toplevel = Accessible_getChildAtIndex (app, toplevel_n);
 747                   if (Accessible_isComponent (toplevel))
 748                           toplevels = g_list_prepend (toplevels, toplevel);
 749                   else {
 750                           Accessible_unref (toplevel);
 751                           fprintf (stderr, "warning, app toplevel not a component.\n");
 752                   }
 753           }
 754   }
 755
 756   /* sort: at the moment we don't have a good way to sort except to put actives on top */
 757   for (iter = g_list_first (toplevels); iter; iter = iter->next) {
 758           Accessible *toplevel =
 759                   (Accessible *) iter->data;
 760           if (AccessibleStateSet_contains (Accessible_getStateSet (toplevel),
 761                                            SPI_STATE_ACTIVE)) {
 762                   actives = g_list_prepend (actives, toplevel);
 763           }
 764   }
 765
 766   for (iter = g_list_first (actives); iter; iter = actives->next) {
 767           toplevels = g_list_remove (toplevels, iter->data); /* place at end */
 768           toplevels = g_list_append (toplevels, iter->data);
 769   }
 770   g_list_free (actives);
 771
 772   /* for each toplevel, ending with the active one(s),
 773    * clip against children, putting results into appropriate charBuffer.
 774    */
 775   for (iter = g_list_first (toplevels); iter; iter = iter->next) {
 776           toplevel = (Accessible *) iter->data;
 777           if (Accessible_isComponent (toplevel)) {
 778               /* make sure toplevel is visible and not iconified or shaded */
 779               states = Accessible_getStateSet (toplevel);
 780               if (AccessibleStateSet_contains (states, SPI_STATE_VISIBLE)
 781                   && !AccessibleStateSet_contains (states, SPI_STATE_ICONIFIED)
 782                   || isJava) { /* isJava hack! */
 783                       component = Accessible_getComponent (toplevel);
 784                       AccessibleComponent_getExtents (component,
 785                                                       &toplevel_bounds.x,
 786                                                       &toplevel_bounds.y,
 787                                                       &toplevel_bounds.width,
 788                                                       &toplevel_bounds.height,
 789                                                       SPI_COORD_TYPE_SCREEN);
 790                       toplevel_bounds.isEmpty = FALSE;
 791                       for (i = 0; i < SPI_LAYER_LAST_DEFINED; ++i) {
 792                               *clip_bounds[i] = toplevel_bounds;
 793                       }
 794 #ifdef CLIP_DEBUG
 795                       fprintf (stderr, "toplevel clip starting\n");
 796                       debug_chunk_list (reviewBuffers[SPI_LAYER_WIDGET]->text_chunks);
 797 #endif
 798                       clip_into_buffers (toplevel, clip_bounds,
 799                                      reviewBuffers, x, y);
 800               }
 801           }
 802           Accessible_unref (toplevel);
 803   }
 804
 805   string = review_buffer_composite (reviewBuffers);
 806
 807   /* SIMPLE SINGLE-PASS ALGORITHM:*/
 808   /* traverse the tree:
 809    *   keep a pointer to outermost instance of each layer
 810    *   clip against outermost in same layer
 811    *   when this clip occurs, store outermost clipped string in 2d string buffer.
 812    *   string buffer may have attributes to mark component bounds, line art,
 813    *      or attributes of text being reviewed.
 814    *   composite the layers, ignoring NULL chars in the string buffers.
 815    *
 816    * Limitations:
 817    *   sibling clip not correct, text may overwrite if siblings intersect onscreen
 818    *   length of resulting text buffer may vary!
 819    *
 820    * Technical issues:
 821    *   no API for ordering toplevels yet, other than knowing which is ACTIVE.
 822    *   not much implementation for the LAYER API yet, other than menus.
 823    */
 824   g_timer_stop (timer);
 825   fprintf (stderr, "elapsed time = %f s\n", g_timer_elapsed (timer, NULL));
 826
 827   return string;
 828 }
 829
 830 void
 831 report_screen_review_line (const AccessibleEvent *event, void *user_data)
 832 {
 833   static Display *display = NULL;
 834   int x, y, win_x, win_y;
 835   Window root_return, child_return;
 836   unsigned int mask_return;
 837
 838   if (!display) display = XOpenDisplay (getenv ("DISPLAY"));
 839   /*
 840    *  we would prefer to get the x,y info in the above event.
 841    *  At the moment we don't get detail params for "toolkit" events,
 842    *  so for testing purposes we use XQueryPointer.  Actual apps
 843    *  probably shouldn't do this.
 844    */
 845   XQueryPointer (display,
 846                  DefaultRootWindow (display),
 847                  &root_return, &child_return,
 848                  &x, &y,
 849                  &win_x, &win_y,
 850                  &mask_return);
 851
 852   fprintf (stderr, "screen review event %s at %d, %d\n", event->type,
 853            x, y);
 854   fprintf (stderr, "[%s]\n",
 855            get_screen_review_line_at (x, y));
 856 }
 857
 858 void
 859 test_exit ()
 860 {
 861   SPI_deregisterGlobalEventListenerAll (mouseclick_listener);
 862   AccessibleEventListener_unref (mouseclick_listener);
 863 }