app/undo.c

   1 /* Dia -- an diagram creation/manipulation program
   2  * Copyright (C) 1999 Alexander Larsson
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  17  */
  18
  19 #include <config.h>
  20
  21 #include "undo.h"
  22 #include "object_ops.h"
  23 #include "properties.h"
  24 #include "connectionpoint_ops.h"
  25 #include "focus.h"
  26 #include "group.h"
  27 #include "preferences.h"
  28 #include "diagram_tree_window.h"
  29
  30 #if 0
  31 #define DEBUG_PRINTF(args) printf args
  32 #else
  33 #define DEBUG_PRINTF(args)
  34 #endif
  35
  36 static void
  37 transaction_point_pointer(Change *change, Diagram *dia)
  38 {
  39   /* Empty function used to track transactionpoints. */
  40 }
  41
  42 static int
  43 is_transactionpoint(Change *change)
  44 {
  45   return change->apply == transaction_point_pointer;
  46 }
  47
  48 static Change *
  49 new_transactionpoint(void)
  50 {
  51   Change *transaction = g_new(Change, 1);
  52
  53   if (transaction) {
  54     transaction->apply = transaction_point_pointer;
  55     transaction->revert = transaction_point_pointer;
  56     transaction->free = NULL;
  57   }
  58
  59   return transaction;
  60 }
  61
  62 UndoStack *
  63 new_undo_stack(Diagram *dia)
  64 {
  65   UndoStack *stack;
  66   Change *transaction;
  67
  68   stack = g_new(UndoStack, 1);
  69   if (stack!=NULL){
  70     stack->dia = dia;
  71     transaction = new_transactionpoint();
  72     transaction->next = transaction->prev = NULL;
  73     stack->last_change = transaction;
  74     stack->current_change = transaction;
  75     stack->depth = 0;
  76   }
  77   return stack;
  78 }
  79
  80 void
  81 undo_destroy(UndoStack *stack)
  82 {
  83   undo_clear(stack);
  84   g_free(stack->current_change); /* Free first transaction point. */
  85   g_free(stack);
  86 }
  87
  88
  89
  90 static void
  91 undo_remove_redo_info(UndoStack *stack)
  92 {
  93   Change *change;
  94   Change *next_change;
  95
  96   DEBUG_PRINTF(("UNDO: Removing redo info\n"));
  97
  98   change = stack->current_change->next;
  99   stack->current_change->next = NULL;
 100   stack->last_change = stack->current_change;
 101
 102   while (change != NULL) {
 103     next_change = change->next;
 104     if (change->free)
 105       (change->free)(change);
 106     g_free(change);
 107     change = next_change;
 108   }
 109 }
 110
 111 static int
 112 depth(UndoStack *stack)
 113 {
 114   int i;
 115   Change *change;
 116   change = stack->current_change;
 117
 118   i = 0;
 119   while (change->prev != NULL) {
 120     change = change->prev;
 121     i++;
 122   }
 123   return i;
 124 }
 125
 126 void
 127 undo_push_change(UndoStack *stack, Change *change)
 128 {
 129   if (stack->current_change != stack->last_change)
 130     undo_remove_redo_info(stack);
 131
 132   DEBUG_PRINTF(("UNDO: Push new change at %d\n", depth(stack)));
 133
 134   change->prev = stack->last_change;
 135   change->next = NULL;
 136   stack->last_change->next = change;
 137   stack->last_change = change;
 138   stack->current_change = change;
 139 }
 140
 141 static void
 142 undo_delete_lowest_transaction(UndoStack *stack)
 143 {
 144   Change *change;
 145   Change *next_change;
 146
 147   /* Find the lowest change: */
 148   change = stack->current_change;
 149   while (change->prev != NULL) {
 150     change = change->prev;
 151   }
 152
 153   /* Remove changes from the bottom until (and including)
 154    * the first transactionpoint.
 155    * Stop if we reach current_change or NULL.
 156    */
 157   do {
 158     if ( (change == NULL) || (change == stack->current_change))
 159       break;
 160
 161     next_change = change->next;
 162     DEBUG_PRINTF(("freeing one change from the bottom.\n"));
 163     if (change->free)
 164       (change->free)(change);
 165     g_free(change);
 166     change = next_change;
 167   } while (!is_transactionpoint(change));
 168
 169   if (is_transactionpoint(change)) {
 170     stack->depth--;
 171     DEBUG_PRINTF(("Decreasing stack depth to: %d\n", stack->depth));
 172   }
 173   change->prev = NULL;
 174 }
 175
 176 void
 177 undo_set_transactionpoint(UndoStack *stack)
 178 {
 179   Change *transaction;
 180
 181   if (is_transactionpoint(stack->current_change))
 182     return;
 183
 184   DEBUG_PRINTF(("UNDO: Push new transactionpoint at %d\n", depth(stack)));
 185
 186   transaction = new_transactionpoint();
 187
 188   undo_push_change(stack, transaction);
 189   stack->depth++;
 190   DEBUG_PRINTF(("Increasing stack depth to: %d\n", stack->depth));
 191
 192   if (prefs.undo_depth > 0) {
 193     while (stack->depth > prefs.undo_depth){
 194       undo_delete_lowest_transaction(stack);
 195     }
 196   }
 197 }
 198
 199 void
 200 undo_revert_to_last_tp(UndoStack *stack)
 201 {
 202   Change *change;
 203   Change *prev_change;
 204
 205   if (stack->current_change->prev == NULL)
 206     return; /* Can't revert first transactionpoint */
 207
 208   change = stack->current_change;
 209   do {
 210     prev_change = change->prev;
 211     (change->revert)(change, stack->dia);
 212     change = prev_change;
 213   } while (!is_transactionpoint(change));
 214   stack->current_change  = change;
 215   stack->depth--;
 216   DEBUG_PRINTF(("Decreasing stack depth to: %d\n", stack->depth));
 217 }
 218
 219 void
 220 undo_apply_to_next_tp(UndoStack *stack)
 221 {
 222   Change *change;
 223   Change *next_change;
 224
 225   change = stack->current_change;
 226
 227   if (change->next == NULL)
 228     return /* Already at top. */;
 229
 230   do {
 231     next_change = change->next;
 232     (change->apply)(change, stack->dia);
 233     change = next_change;
 234   } while ( (change != NULL) &&
 235             (!is_transactionpoint(change)) );
 236   if (change == NULL)
 237     change = stack->last_change;
 238   stack->current_change = change;
 239   stack->depth++;
 240   DEBUG_PRINTF(("Increasing stack depth to: %d\n", stack->depth));
 241 }
 242
 243
 244 void
 245 undo_clear(UndoStack *stack)
 246 {
 247   Change *change;
 248
 249   DEBUG_PRINTF(("undo_clear()\n"));
 250
 251   change = stack->current_change;
 252
 253   while (change->prev != NULL) {
 254     change = change->prev;
 255   }
 256
 257   stack->current_change = change;
 258   stack->depth = 0;
 259   undo_remove_redo_info(stack);
 260 }
 261
 262
 263 /****************************************************************/
 264 /****************************************************************/
 265 /*****************                          *********************/
 266 /***************** Specific undo functions: *********************/
 267 /*****************                          *********************/
 268 /****************************************************************/
 269 /****************************************************************/
 270
 271 /******** Move object list: */
 272
 273 struct MoveObjectsChange {
 274   Change change;
 275
 276   Point *orig_pos;
 277   Point *dest_pos;
 278   GList *obj_list;
 279 };
 280
 281 static void
 282 move_objects_apply(struct MoveObjectsChange *change, Diagram *dia)
 283 {
 284   GList *list;
 285   int i;
 286   Object *obj;
 287
 288   object_add_updates_list(change->obj_list, dia);
 289
 290   list = change->obj_list;
 291   i=0;
 292   while (list != NULL) {
 293     obj = (Object *)  list->data;
 294
 295     obj->ops->move(obj, &change->dest_pos[i]);
 296
 297     list = g_list_next(list); i++;
 298   }
 299
 300   list = change->obj_list;
 301   while (list!=NULL) {
 302     obj = (Object *) list->data;
 303
 304     diagram_update_connections_object(dia, obj, TRUE);
 305
 306     list = g_list_next(list);
 307   }
 308
 309   object_add_updates_list(change->obj_list, dia);
 310 }
 311
 312 static void
 313 move_objects_revert(struct MoveObjectsChange *change, Diagram *dia)
 314 {
 315   GList *list;
 316   int i;
 317   Object *obj;
 318
 319   object_add_updates_list(change->obj_list, dia);
 320
 321   list = change->obj_list;
 322   i=0;
 323   while (list != NULL) {
 324     obj = (Object *)  list->data;
 325
 326     obj->ops->move(obj, &change->orig_pos[i]);
 327
 328     list = g_list_next(list); i++;
 329   }
 330
 331   list = change->obj_list;
 332   while (list!=NULL) {
 333     obj = (Object *) list->data;
 334
 335     diagram_update_connections_object(dia, obj, TRUE);
 336
 337     list = g_list_next(list);
 338   }
 339
 340   object_add_updates_list(change->obj_list, dia);
 341 }
 342
 343 static void
 344 move_objects_free(struct MoveObjectsChange *change)
 345 {
 346   g_free(change->orig_pos);
 347   g_free(change->dest_pos);
 348   g_list_free(change->obj_list);
 349 }
 350
 351 extern Change *
 352 undo_move_objects(Diagram *dia, Point *orig_pos, Point *dest_pos,
 353                   GList *obj_list)
 354 {
 355   struct MoveObjectsChange *change;
 356
 357   change = g_new(struct MoveObjectsChange, 1);
 358
 359   change->change.apply = (UndoApplyFunc) move_objects_apply;
 360   change->change.revert = (UndoRevertFunc) move_objects_revert;
 361   change->change.free = (UndoFreeFunc) move_objects_free;
 362
 363   change->orig_pos = orig_pos;
 364   change->dest_pos = dest_pos;
 365   change->obj_list = obj_list;
 366
 367   DEBUG_PRINTF(("UNDO: Push new move objects at %d\n", depth(dia->undo)));
 368   undo_push_change(dia->undo, (Change *) change);
 369   return (Change *)change;
 370 }
 371
 372 /********** Move handle: */
 373
 374 struct MoveHandleChange {
 375   Change change;
 376
 377   Point orig_pos;
 378   Point dest_pos;
 379   Handle *handle;
 380   Object *obj;
 381 };
 382
 383 static void
 384 move_handle_apply(struct MoveHandleChange *change, Diagram *dia)
 385 {
 386   object_add_updates(change->obj, dia);
 387   change->obj->ops->move_handle(change->obj, change->handle,
 388                                  &change->dest_pos,
 389                                  HANDLE_MOVE_USER_FINAL,0);
 390   object_add_updates(change->obj, dia);
 391   diagram_update_connections_object(dia, change->obj, TRUE);
 392 }
 393
 394 static void
 395 move_handle_revert(struct MoveHandleChange *change, Diagram *dia)
 396 {
 397   object_add_updates(change->obj, dia);
 398   change->obj->ops->move_handle(change->obj, change->handle,
 399                                  &change->orig_pos,
 400                                  HANDLE_MOVE_USER_FINAL,0);
 401   object_add_updates(change->obj, dia);
 402   diagram_update_connections_object(dia, change->obj, TRUE);
 403 }
 404
 405 static void
 406 move_handle_free(struct MoveHandleChange *change)
 407 {
 408 }
 409
 410
 411 Change *
 412 undo_move_handle(Diagram *dia,
 413                  Handle *handle, Object *obj,
 414                  Point orig_pos, Point dest_pos)
 415 {
 416   struct MoveHandleChange *change;
 417
 418   change = g_new(struct MoveHandleChange, 1);
 419
 420   change->change.apply = (UndoApplyFunc) move_handle_apply;
 421   change->change.revert = (UndoRevertFunc) move_handle_revert;
 422   change->change.free = (UndoFreeFunc) move_handle_free;
 423
 424   change->orig_pos = orig_pos;
 425   change->dest_pos = dest_pos;
 426   change->handle = handle;
 427   change->obj = obj;
 428
 429   DEBUG_PRINTF(("UNDO: Push new move handle at %d\n", depth(dia->undo)));
 430
 431   undo_push_change(dia->undo, (Change *) change);
 432   return (Change *)change;
 433 }
 434
 435 /***************** Connect object: */
 436
 437 struct ConnectChange {
 438   Change change;
 439
 440   Object *obj;
 441   Handle *handle;
 442   ConnectionPoint *connectionpoint;
 443   Point handle_pos;
 444 };
 445
 446 static void
 447 connect_apply(struct ConnectChange *change, Diagram *dia)
 448 {
 449   object_connect(change->obj, change->handle, change->connectionpoint);
 450
 451   object_add_updates(change->obj, dia);
 452   change->obj->ops->move_handle(change->obj, change->handle ,
 453                                 &change->connectionpoint->pos,
 454                                 HANDLE_MOVE_CONNECTED, 0);
 455
 456   object_add_updates(change->obj, dia);
 457 }
 458
 459 static void
 460 connect_revert(struct ConnectChange *change, Diagram *dia)
 461 {
 462   object_unconnect(change->obj, change->handle);
 463
 464   object_add_updates(change->obj, dia);
 465   change->obj->ops->move_handle(change->obj, change->handle ,
 466                                 &change->handle_pos,
 467                                 HANDLE_MOVE_CONNECTED, 0);
 468
 469   object_add_updates(change->obj, dia);
 470 }
 471
 472 static void
 473 connect_free(struct ConnectChange *change)
 474 {
 475 }
 476
 477 extern Change *
 478 undo_connect(Diagram *dia, Object *obj, Handle *handle,
 479              ConnectionPoint *connectionpoint)
 480 {
 481   struct ConnectChange *change;
 482
 483   change = g_new(struct ConnectChange, 1);
 484
 485   change->change.apply = (UndoApplyFunc) connect_apply;
 486   change->change.revert = (UndoRevertFunc) connect_revert;
 487   change->change.free = (UndoFreeFunc) connect_free;
 488
 489   change->obj = obj;
 490   change->handle = handle;
 491   change->handle_pos = handle->pos;
 492   change->connectionpoint = connectionpoint;
 493
 494   DEBUG_PRINTF(("UNDO: Push new connect at %d\n", depth(dia->undo)));
 495   undo_push_change(dia->undo, (Change *) change);
 496   return (Change *)change;
 497 }
 498
 499 /*************** Unconnect object: */
 500
 501 struct UnconnectChange {
 502   Change change;
 503
 504   Object *obj;
 505   Handle *handle;
 506   ConnectionPoint *connectionpoint;
 507 };
 508
 509 static void
 510 unconnect_apply(struct UnconnectChange *change, Diagram *dia)
 511 {
 512   object_unconnect(change->obj, change->handle);
 513
 514   object_add_updates(change->obj, dia);
 515 }
 516
 517 static void
 518 unconnect_revert(struct UnconnectChange *change, Diagram *dia)
 519 {
 520   object_connect(change->obj, change->handle, change->connectionpoint);
 521
 522   object_add_updates(change->obj, dia);
 523 }
 524
 525 static void
 526 unconnect_free(struct UnconnectChange *change)
 527 {
 528 }
 529
 530 extern Change *
 531 undo_unconnect(Diagram *dia, Object *obj, Handle *handle)
 532 {
 533   struct UnconnectChange *change;
 534
 535   change = g_new(struct UnconnectChange, 1);
 536
 537   change->change.apply = (UndoApplyFunc) unconnect_apply;
 538   change->change.revert = (UndoRevertFunc) unconnect_revert;
 539   change->change.free = (UndoFreeFunc) unconnect_free;
 540
 541   change->obj = obj;
 542   change->handle = handle;
 543   change->connectionpoint = handle->connected_to;
 544
 545   DEBUG_PRINTF(("UNDO: Push new unconnect at %d\n", depth(dia->undo)));
 546   undo_push_change(dia->undo, (Change *) change);
 547   return (Change *)change;
 548 }
 549
 550
 551 /******** Delete object list: */
 552
 553 struct DeleteObjectsChange {
 554   Change change;
 555
 556   Layer *layer;
 557   GList *obj_list; /* Owning reference when applied */
 558   GList *original_objects;
 559   int applied;
 560 };
 561
 562 static void
 563 delete_objects_apply(struct DeleteObjectsChange *change, Diagram *dia)
 564 {
 565   GList *list;
 566
 567   DEBUG_PRINTF(("delete_objects_apply()\n"));
 568   change->applied = 1;
 569   diagram_unselect_objects(dia, change->obj_list);
 570   layer_remove_objects(change->layer, change->obj_list);
 571   object_add_updates_list(change->obj_list, dia);
 572
 573   list = change->obj_list;
 574   while (list != NULL) {
 575     Object *obj = (Object *)list->data;
 576
 577   /* Have to hide any open properties dialog
 578      if it contains some object in cut_list */
 579     properties_hide_if_shown(dia, obj);
 580
 581     /* Remove focus if active */
 582     if ((active_focus()!=NULL) && (active_focus()->obj == obj)) {
 583       remove_focus();
 584     }
 585
 586     list = g_list_next(list);
 587   }
 588
 589   diagram_tree_remove_objects(diagram_tree(), change->obj_list);
 590 }
 591
 592 static void
 593 delete_objects_revert(struct DeleteObjectsChange *change, Diagram *dia)
 594 {
 595   DEBUG_PRINTF(("delete_objects_revert()\n"));
 596   change->applied = 0;
 597   layer_set_object_list(change->layer,
 598                         g_list_copy(change->original_objects));
 599   object_add_updates_list(change->obj_list, dia);
 600   diagram_tree_add_objects(diagram_tree(), dia, change->obj_list);
 601 }
 602
 603 static void
 604 delete_objects_free(struct DeleteObjectsChange *change)
 605 {
 606   DEBUG_PRINTF(("delete_objects_free()\n"));
 607   if (change->applied)
 608     destroy_object_list(change->obj_list);
 609   else
 610     g_list_free(change->obj_list);
 611   g_list_free(change->original_objects);
 612 }
 613
 614 Change *
 615 undo_delete_objects(Diagram *dia, GList *obj_list)
 616 {
 617   struct DeleteObjectsChange *change;
 618
 619   change = g_new(struct DeleteObjectsChange, 1);
 620
 621   change->change.apply = (UndoApplyFunc) delete_objects_apply;
 622   change->change.revert = (UndoRevertFunc) delete_objects_revert;
 623   change->change.free = (UndoFreeFunc) delete_objects_free;
 624
 625   change->layer = dia->data->active_layer;
 626   change->obj_list = obj_list;
 627   change->original_objects = g_list_copy(dia->data->active_layer->objects);
 628   change->applied = 0;
 629
 630   DEBUG_PRINTF(("UNDO: Push new delete objects at %d\n", depth(dia->undo)));
 631   undo_push_change(dia->undo, (Change *) change);
 632   return (Change *)change;
 633 }
 634
 635 /******** Insert object list: */
 636
 637 struct InsertObjectsChange {
 638   Change change;
 639
 640   Layer *layer;
 641   GList *obj_list; /* Owning reference when not applied */
 642   int applied;
 643 };
 644
 645 static void
 646 insert_objects_apply(struct InsertObjectsChange *change, Diagram *dia)
 647 {
 648   DEBUG_PRINTF(("insert_objects_apply()\n"));
 649   change->applied = 1;
 650   layer_add_objects(change->layer, g_list_copy(change->obj_list));
 651   object_add_updates_list(change->obj_list, dia);
 652   diagram_tree_add_objects(diagram_tree(), dia, change->obj_list);
 653 }
 654
 655 static void
 656 insert_objects_revert(struct InsertObjectsChange *change, Diagram *dia)
 657 {
 658   GList *list;
 659
 660   DEBUG_PRINTF(("insert_objects_revert()\n"));
 661   change->applied = 0;
 662   diagram_unselect_objects(dia, change->obj_list);
 663   layer_remove_objects(change->layer, change->obj_list);
 664   object_add_updates_list(change->obj_list, dia);
 665
 666   list = change->obj_list;
 667   while (list != NULL) {
 668     Object *obj = (Object *)list->data;
 669
 670   /* Have to hide any open properties dialog
 671      if it contains some object in cut_list */
 672     properties_hide_if_shown(dia, obj);
 673
 674     /* Remove focus if active */
 675     if ((active_focus()!=NULL) && (active_focus()->obj == obj)) {
 676       remove_focus();
 677     }
 678
 679     list = g_list_next(list);
 680   }
 681
 682   diagram_tree_remove_objects(diagram_tree(), change->obj_list);
 683 }
 684
 685 static void
 686 insert_objects_free(struct InsertObjectsChange *change)
 687 {
 688   DEBUG_PRINTF(("insert_objects_free()\n"));
 689   if (!change->applied)
 690     destroy_object_list(change->obj_list);
 691   else
 692     g_list_free(change->obj_list);
 693 }
 694
 695 Change *
 696 undo_insert_objects(Diagram *dia, GList *obj_list, int applied)
 697 {
 698   struct InsertObjectsChange *change;
 699
 700   change = g_new(struct InsertObjectsChange, 1);
 701
 702   change->change.apply = (UndoApplyFunc) insert_objects_apply;
 703   change->change.revert = (UndoRevertFunc) insert_objects_revert;
 704   change->change.free = (UndoFreeFunc) insert_objects_free;
 705
 706   change->layer = dia->data->active_layer;
 707   change->obj_list = obj_list;
 708   change->applied = applied;
 709
 710   DEBUG_PRINTF(("UNDO: Push new insert objects at %d\n", depth(dia->undo)));
 711   undo_push_change(dia->undo, (Change *) change);
 712   return (Change *)change;
 713 }
 714
 715 /******** Reorder object list: */
 716
 717 struct ReorderObjectsChange {
 718   Change change;
 719
 720   Layer *layer;
 721   GList *changed_list; /* Owning reference when applied */
 722   GList *original_objects;
 723   GList *reordered_objects;
 724 };
 725
 726 static void
 727 reorder_objects_apply(struct ReorderObjectsChange *change, Diagram *dia)
 728 {
 729   DEBUG_PRINTF(("reorder_objects_apply()\n"));
 730   layer_set_object_list(change->layer,
 731                         g_list_copy(change->reordered_objects));
 732   object_add_updates_list(change->changed_list, dia);
 733 }
 734
 735 static void
 736 reorder_objects_revert(struct ReorderObjectsChange *change, Diagram *dia)
 737 {
 738   DEBUG_PRINTF(("reorder_objects_revert()\n"));
 739   layer_set_object_list(change->layer,
 740                         g_list_copy(change->original_objects));
 741   object_add_updates_list(change->changed_list, dia);
 742 }
 743
 744 static void
 745 reorder_objects_free(struct ReorderObjectsChange *change)
 746 {
 747   DEBUG_PRINTF(("reorder_objects_free()\n"));
 748   g_list_free(change->changed_list);
 749   g_list_free(change->original_objects);
 750   g_list_free(change->reordered_objects);
 751 }
 752
 753 Change *
 754 undo_reorder_objects(Diagram *dia, GList *changed_list, GList *orig_list)
 755 {
 756   struct ReorderObjectsChange *change;
 757
 758   change = g_new(struct ReorderObjectsChange, 1);
 759
 760   change->change.apply = (UndoApplyFunc) reorder_objects_apply;
 761   change->change.revert = (UndoRevertFunc) reorder_objects_revert;
 762   change->change.free = (UndoFreeFunc) reorder_objects_free;
 763
 764   change->layer = dia->data->active_layer;
 765   change->changed_list = changed_list;
 766   change->original_objects = orig_list;
 767   change->reordered_objects = g_list_copy(dia->data->active_layer->objects);
 768
 769   DEBUG_PRINTF(("UNDO: Push new reorder objects at %d\n", depth(dia->undo)));
 770   undo_push_change(dia->undo, (Change *) change);
 771   return (Change *)change;
 772 }
 773
 774 /******** ObjectChange: */
 775
 776 struct ObjectChangeChange {
 777   Change change;
 778
 779   Object *obj;
 780   ObjectChange *obj_change;
 781 };
 782
 783
 784 static void
 785 object_change_apply(struct ObjectChangeChange *change,
 786                     Diagram *dia)
 787 {
 788   object_add_updates(change->obj, dia);
 789   change->obj_change->apply(change->obj_change, change->obj);
 790   { /* Make sure object updates its data: */
 791     Point p = change->obj->position;
 792     (change->obj->ops->move)(change->obj,&p);
 793   }
 794   object_add_updates(change->obj, dia);
 795
 796   diagram_update_connections_object(dia, change->obj, TRUE);
 797
 798   properties_update_if_shown(dia, change->obj);
 799 }
 800
 801 static void
 802 object_change_revert(struct ObjectChangeChange *change,
 803                      Diagram *dia)
 804 {
 805   object_add_updates(change->obj, dia);
 806   change->obj_change->revert(change->obj_change, change->obj);
 807   { /* Make sure object updates its data: */
 808     Point p = change->obj->position;
 809     (change->obj->ops->move)(change->obj,&p);
 810   }
 811   object_add_updates(change->obj, dia);
 812
 813   diagram_update_connections_object(dia, change->obj, TRUE);
 814
 815   properties_update_if_shown(dia, change->obj);
 816 }
 817
 818 static void
 819 object_change_free(struct ObjectChangeChange *change)
 820 {
 821   DEBUG_PRINTF(("state_change_free()\n"));
 822   if (change->obj_change->free)
 823     (*change->obj_change->free)(change->obj_change);
 824   g_free(change->obj_change);
 825 }
 826
 827 Change *
 828 undo_object_change(Diagram *dia, Object *obj,
 829                    ObjectChange *obj_change)
 830 {
 831   struct ObjectChangeChange *change;
 832
 833   change = g_new(struct ObjectChangeChange, 1);
 834
 835   change->change.apply = (UndoApplyFunc) object_change_apply;
 836   change->change.revert = (UndoRevertFunc) object_change_revert;
 837   change->change.free = (UndoFreeFunc) object_change_free;
 838
 839   change->obj = obj;
 840   change->obj_change = obj_change;
 841
 842   DEBUG_PRINTF(("UNDO: Push new obj_change at %d\n", depth(dia->undo)));
 843   undo_push_change(dia->undo, (Change *) change);
 844   return (Change *)change;
 845 }
 846
 847 /******** Group object list: */
 848
 849 struct GroupObjectsChange {
 850   Change change;
 851
 852   Layer *layer;
 853   Object *group;   /* owning reference if not applied */
 854   GList *obj_list; /* This list is owned by the group. */
 855   GList *orig_list; /* This list (not the object) is owned */
 856   int applied;
 857 };
 858
 859 static void
 860 group_objects_apply(struct GroupObjectsChange *change, Diagram *dia)
 861 {
 862   GList *list;
 863
 864   DEBUG_PRINTF(("group_objects_apply()\n"));
 865
 866   change->applied = 1;
 867
 868   diagram_unselect_objects(dia, change->obj_list);
 869   layer_remove_objects(change->layer, change->obj_list);
 870   layer_add_object(change->layer, change->group);
 871   object_add_updates(change->group, dia);
 872
 873   list = change->obj_list;
 874   while (list != NULL) {
 875     Object *obj = (Object *)list->data;
 876
 877   /* Have to hide any open properties dialog
 878      if it contains some object in cut_list */
 879     properties_hide_if_shown(dia, obj);
 880
 881     /* Remove focus if active */
 882     if ((active_focus()!=NULL) && (active_focus()->obj == obj)) {
 883       remove_focus();
 884     }
 885
 886     list = g_list_next(list);
 887   }
 888
 889   diagram_tree_remove_objects(diagram_tree(), change->obj_list);
 890   diagram_tree_add_object(diagram_tree(), dia, change->group);
 891 }
 892
 893 static void
 894 group_objects_revert(struct GroupObjectsChange *change, Diagram *dia)
 895 {
 896   GList *old_list;
 897
 898   DEBUG_PRINTF(("group_objects_revert()\n"));
 899   change->applied = 0;
 900
 901   diagram_unselect_object(dia, change->group);
 902   object_add_updates(change->group, dia);
 903
 904   old_list = change->layer->objects;
 905   change->layer->objects = g_list_copy(change->orig_list);
 906   g_list_free(old_list);
 907
 908   object_add_updates_list(change->obj_list, dia);
 909
 910   properties_hide_if_shown(dia, change->group);
 911
 912   diagram_tree_remove_object(diagram_tree(), change->group);
 913   diagram_tree_add_objects(diagram_tree(), dia, change->obj_list);
 914 }
 915
 916 static void
 917 group_objects_free(struct GroupObjectsChange *change)
 918 {
 919   DEBUG_PRINTF(("group_objects_free()\n"));
 920   if (!change->applied) {
 921     group_destroy_shallow(change->group);
 922     change->group = NULL;
 923     change->obj_list = NULL;
 924   }
 925   g_list_free(change->orig_list);
 926 }
 927
 928 Change *
 929 undo_group_objects(Diagram *dia, GList *obj_list, Object *group,
 930                    GList *orig_list)
 931 {
 932   struct GroupObjectsChange *change;
 933
 934   change = g_new(struct GroupObjectsChange, 1);
 935
 936   change->change.apply = (UndoApplyFunc) group_objects_apply;
 937   change->change.revert = (UndoRevertFunc) group_objects_revert;
 938   change->change.free = (UndoFreeFunc) group_objects_free;
 939
 940   change->layer = dia->data->active_layer;
 941   change->group = group;
 942   change->obj_list = obj_list;
 943   change->orig_list = orig_list;
 944   change->applied = 1;
 945
 946   DEBUG_PRINTF(("UNDO: Push new group objects at %d\n", depth(dia->undo)));
 947   undo_push_change(dia->undo, (Change *) change);
 948   return (Change *)change;
 949 }
 950
 951 /******** Ungroup object list: */
 952
 953 struct UngroupObjectsChange {
 954   Change change;
 955
 956   Layer *layer;
 957   Object *group;   /* owning reference if applied */
 958   GList *obj_list; /* This list is owned by the ungroup. */
 959   int group_index;
 960   int applied;
 961 };
 962
 963 static void
 964 ungroup_objects_apply(struct UngroupObjectsChange *change, Diagram *dia)
 965 {
 966   DEBUG_PRINTF(("ungroup_objects_apply()\n"));
 967
 968   change->applied = 1;
 969
 970   diagram_unselect_object(dia, change->group);
 971   object_add_updates(change->group, dia);
 972   layer_replace_object_with_list(change->layer, change->group,
 973                                  g_list_copy(change->obj_list));
 974   object_add_updates_list(change->obj_list, dia);
 975
 976   properties_hide_if_shown(dia, change->group);
 977 }
 978
 979 static void
 980 ungroup_objects_revert(struct UngroupObjectsChange *change, Diagram *dia)
 981 {
 982   GList *list;
 983
 984   DEBUG_PRINTF(("ungroup_objects_revert()\n"));
 985   change->applied = 0;
 986
 987
 988   diagram_unselect_objects(dia, change->obj_list);
 989   layer_remove_objects(change->layer, change->obj_list);
 990   layer_add_object_at(change->layer, change->group, change->group_index);
 991   object_add_updates(change->group, dia);
 992
 993   list = change->obj_list;
 994   while (list != NULL) {
 995     Object *obj = (Object *)list->data;
 996
 997   /* Have to hide any open properties dialog
 998      if it contains some object in cut_list */
 999     properties_hide_if_shown(dia, obj);
1000
1001     /* Remove focus if active */
1002     if ((active_focus()!=NULL) && (active_focus()->obj == obj)) {
1003       remove_focus();
1004     }
1005
1006     list = g_list_next(list);
1007   }
1008
1009   diagram_tree_remove_objects(diagram_tree(), change->obj_list);
1010   diagram_tree_add_object(diagram_tree(), dia, change->group);
1011 }
1012
1013 static void
1014 ungroup_objects_free(struct UngroupObjectsChange *change)
1015 {
1016   DEBUG_PRINTF(("ungroup_objects_free()\n"));
1017   if (change->applied) {
1018     group_destroy_shallow(change->group);
1019     change->group = NULL;
1020     change->obj_list = NULL;
1021   }
1022 }
1023
1024 Change *
1025 undo_ungroup_objects(Diagram *dia, GList *obj_list, Object *group,
1026                      int group_index)
1027 {
1028   struct UngroupObjectsChange *change;
1029
1030   change = g_new(struct UngroupObjectsChange, 1);
1031
1032   change->change.apply = (UndoApplyFunc) ungroup_objects_apply;
1033   change->change.revert = (UndoRevertFunc) ungroup_objects_revert;
1034   change->change.free = (UndoFreeFunc) ungroup_objects_free;
1035
1036   change->layer = dia->data->active_layer;
1037   change->group = group;
1038   change->obj_list = obj_list;
1039   change->group_index = group_index;
1040   change->applied = 1;
1041
1042   DEBUG_PRINTF(("UNDO: Push new ungroup objects at %d\n", depth(dia->undo)));
1043   undo_push_change(dia->undo, (Change *) change);
1044   return (Change *)change;
1045 }
1046