dlls/riched20/undo.c

   1 /*
   2  * RichEdit - functions dealing with editor object
   3  *
   4  * Copyright 2004 by Krzysztof Foltman
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  19  */
  20
  21 #include "editor.h"
  22
  23 WINE_DEFAULT_DEBUG_CHANNEL(richedit);
  24
  25 static void destroy_undo_item( struct undo_item *undo )
  26 {
  27     switch( undo->type )
  28     {
  29     case undo_insert_run:
  30         heap_free( undo->u.insert_run.str );
  31         ME_ReleaseStyle( undo->u.insert_run.style );
  32         break;
  33     case undo_split_para:
  34         ME_DestroyString( undo->u.split_para.eol_str );
  35         break;
  36     default:
  37         break;
  38     }
  39
  40     heap_free( undo );
  41 }
  42
  43 static void empty_redo_stack(ME_TextEditor *editor)
  44 {
  45     struct undo_item *cursor, *cursor2;
  46     LIST_FOR_EACH_ENTRY_SAFE( cursor, cursor2, &editor->redo_stack, struct undo_item, entry )
  47     {
  48         list_remove( &cursor->entry );
  49         destroy_undo_item( cursor );
  50     }
  51 }
  52
  53 void ME_EmptyUndoStack(ME_TextEditor *editor)
  54 {
  55   struct undo_item *cursor, *cursor2;
  56   if (editor->nUndoMode == umIgnore)
  57     return;
  58
  59   TRACE("Emptying undo stack\n");
  60
  61   editor->nUndoStackSize = 0;
  62
  63   LIST_FOR_EACH_ENTRY_SAFE( cursor, cursor2, &editor->undo_stack, struct undo_item, entry )
  64   {
  65       list_remove( &cursor->entry );
  66       destroy_undo_item( cursor );
  67   }
  68
  69   empty_redo_stack( editor );
  70 }
  71
  72 static struct undo_item *add_undo( ME_TextEditor *editor, enum undo_type type )
  73 {
  74     struct undo_item *undo, *item;
  75     struct list *head;
  76
  77     if (editor->nUndoMode == umIgnore) return NULL;
  78     if (editor->nUndoLimit == 0) return NULL;
  79
  80     undo = heap_alloc( sizeof(*undo) );
  81     if (!undo) return NULL;
  82     undo->type = type;
  83
  84     if (editor->nUndoMode == umAddToUndo || editor->nUndoMode == umAddBackToUndo)
  85     {
  86
  87         head = list_head( &editor->undo_stack );
  88         if (head)
  89         {
  90             item = LIST_ENTRY( head, struct undo_item, entry );
  91             if (item->type == undo_potential_end_transaction)
  92                 item->type = undo_end_transaction;
  93         }
  94
  95         if (editor->nUndoMode == umAddToUndo)
  96             TRACE("Pushing id=%d to undo stack, deleting redo stack\n", type);
  97         else
  98             TRACE("Pushing id=%d to undo stack\n", type);
  99
 100         list_add_head( &editor->undo_stack, &undo->entry );
 101
 102         if (type == undo_end_transaction || type == undo_potential_end_transaction)
 103             editor->nUndoStackSize++;
 104
 105         if (editor->nUndoStackSize > editor->nUndoLimit)
 106         {
 107             struct undo_item *cursor2;
 108             /* remove oldest undo from stack */
 109             LIST_FOR_EACH_ENTRY_SAFE_REV( item, cursor2, &editor->undo_stack, struct undo_item, entry )
 110             {
 111                 BOOL done = (item->type == undo_end_transaction);
 112                 list_remove( &item->entry );
 113                 destroy_undo_item( item );
 114                 if (done) break;
 115             }
 116             editor->nUndoStackSize--;
 117         }
 118
 119         /* any new operation (not redo) clears the redo stack */
 120         if (editor->nUndoMode == umAddToUndo) empty_redo_stack( editor );
 121     }
 122     else if (editor->nUndoMode == umAddToRedo)
 123     {
 124         TRACE("Pushing id=%d to redo stack\n", type);
 125         list_add_head( &editor->redo_stack, &undo->entry );
 126     }
 127
 128     return undo;
 129 }
 130
 131 BOOL add_undo_insert_run( ME_TextEditor *editor, int pos, const WCHAR *str, int len, int flags, ME_Style *style )
 132 {
 133     struct undo_item *undo = add_undo( editor, undo_insert_run );
 134     if (!undo) return FALSE;
 135
 136     undo->u.insert_run.str = heap_alloc( (len + 1) * sizeof(WCHAR) );
 137     if (!undo->u.insert_run.str)
 138     {
 139         ME_EmptyUndoStack( editor );
 140         return FALSE;
 141     }
 142     memcpy( undo->u.insert_run.str, str, len * sizeof(WCHAR) );
 143     undo->u.insert_run.str[len] = 0;
 144     undo->u.insert_run.pos = pos;
 145     undo->u.insert_run.len = len;
 146     undo->u.insert_run.flags = flags;
 147     undo->u.insert_run.style = style;
 148     ME_AddRefStyle( style );
 149     return TRUE;
 150 }
 151
 152 BOOL add_undo_set_para_fmt( ME_TextEditor *editor, const ME_Paragraph *para )
 153 {
 154     struct undo_item *undo = add_undo( editor, undo_set_para_fmt );
 155     if (!undo) return FALSE;
 156
 157     undo->u.set_para_fmt.pos = para->nCharOfs;
 158     undo->u.set_para_fmt.fmt = *para->pFmt;
 159     undo->u.set_para_fmt.border = para->border;
 160
 161     return TRUE;
 162 }
 163
 164 BOOL add_undo_set_char_fmt( ME_TextEditor *editor, int pos, int len, const CHARFORMAT2W *fmt )
 165 {
 166     struct undo_item *undo = add_undo( editor, undo_set_char_fmt );
 167     if (!undo) return FALSE;
 168
 169     undo->u.set_char_fmt.pos = pos;
 170     undo->u.set_char_fmt.len = len;
 171     undo->u.set_char_fmt.fmt = *fmt;
 172
 173     return TRUE;
 174 }
 175
 176 BOOL add_undo_join_paras( ME_TextEditor *editor, int pos )
 177 {
 178     struct undo_item *undo = add_undo( editor, undo_join_paras );
 179     if (!undo) return FALSE;
 180
 181     undo->u.join_paras.pos = pos;
 182     return TRUE;
 183 }
 184
 185 BOOL add_undo_split_para( ME_TextEditor *editor, const ME_Paragraph *para, ME_String *eol_str, const ME_Cell *cell )
 186 {
 187     struct undo_item *undo = add_undo( editor, undo_split_para );
 188     if (!undo) return FALSE;
 189
 190     undo->u.split_para.pos = para->nCharOfs - eol_str->nLen;
 191     undo->u.split_para.eol_str = eol_str;
 192     undo->u.split_para.fmt = *para->pFmt;
 193     undo->u.split_para.border = para->border;
 194     undo->u.split_para.flags = para->prev_para->member.para.nFlags & ~MEPF_CELL;
 195
 196     if (cell)
 197     {
 198         undo->u.split_para.cell_border = cell->border;
 199         undo->u.split_para.cell_right_boundary = cell->nRightBoundary;
 200     }
 201     return TRUE;
 202 }
 203
 204 BOOL add_undo_delete_run( ME_TextEditor *editor, int pos, int len )
 205 {
 206     struct undo_item *undo = add_undo( editor, undo_delete_run );
 207     if (!undo) return FALSE;
 208
 209     undo->u.delete_run.pos = pos;
 210     undo->u.delete_run.len = len;
 211
 212     return TRUE;
 213 }
 214
 215 /**
 216  * Commits preceding changes into a transaction that can be undone together.
 217  *
 218  * This should be called after all the changes occur associated with an event
 219  * so that the group of changes can be undone atomically as a transaction.
 220  *
 221  * This will have no effect the undo mode is set to ignore changes, or if no
 222  * changes preceded calling this function before the last time it was called.
 223  *
 224  * This can also be used to conclude a coalescing transaction (used for grouping
 225  * typed characters).
 226  */
 227 void ME_CommitUndo(ME_TextEditor *editor)
 228 {
 229   struct undo_item *item;
 230   struct list *head;
 231
 232   if (editor->nUndoMode == umIgnore)
 233     return;
 234
 235   assert(editor->nUndoMode == umAddToUndo);
 236
 237   /* no transactions, no need to commit */
 238   head = list_head( &editor->undo_stack );
 239   if (!head) return;
 240
 241   /* no need to commit empty transactions */
 242   item = LIST_ENTRY( head, struct undo_item, entry );
 243   if (item->type == undo_end_transaction) return;
 244
 245   if (item->type == undo_potential_end_transaction)
 246   {
 247       item->type = undo_end_transaction;
 248       return;
 249   }
 250
 251   add_undo( editor, undo_end_transaction );
 252 }
 253
 254 /**
 255  * Groups subsequent changes with previous ones for an undo if coalescing.
 256  *
 257  * Has no effect if the previous changes were followed by a ME_CommitUndo. This
 258  * function will only have an affect if the previous changes were followed by
 259  * a call to ME_CommitCoalescingUndo, which allows the transaction to be
 260  * continued.
 261  *
 262  * This allows multiple consecutively typed characters to be grouped together
 263  * to be undone by a single undo operation.
 264  */
 265 void ME_ContinueCoalescingTransaction(ME_TextEditor *editor)
 266 {
 267   struct undo_item *item;
 268   struct list *head;
 269
 270   if (editor->nUndoMode == umIgnore)
 271     return;
 272
 273   assert(editor->nUndoMode == umAddToUndo);
 274
 275   head = list_head( &editor->undo_stack );
 276   if (!head) return;
 277
 278   item = LIST_ENTRY( head, struct undo_item, entry );
 279   if (item->type == undo_potential_end_transaction)
 280   {
 281     list_remove( &item->entry );
 282     editor->nUndoStackSize--;
 283     destroy_undo_item( item );
 284   }
 285 }
 286
 287 /**
 288  * Commits preceding changes into a undo transaction that can be expanded.
 289  *
 290  * This function allows the transaction to be reopened with
 291  * ME_ContinueCoalescingTransaction in order to continue the transaction.  If an
 292  * undo item is added to the undo stack as a result of a change without the
 293  * transaction being reopened, then the transaction will be ended, and the
 294  * changes will become a part of the next transaction.
 295  *
 296  * This is used to allow typed characters to be grouped together since each
 297  * typed character results in a single event, and each event adding undo items
 298  * must be committed.  Using this function as opposed to ME_CommitUndo allows
 299  * multiple events to be grouped, and undone together.
 300  */
 301 void ME_CommitCoalescingUndo(ME_TextEditor *editor)
 302 {
 303   struct undo_item *item;
 304   struct list *head;
 305
 306   if (editor->nUndoMode == umIgnore)
 307     return;
 308
 309   assert(editor->nUndoMode == umAddToUndo);
 310
 311   head = list_head( &editor->undo_stack );
 312   if (!head) return;
 313
 314   /* no need to commit empty transactions */
 315   item = LIST_ENTRY( head, struct undo_item, entry );
 316   if (item->type == undo_end_transaction ||
 317       item->type == undo_potential_end_transaction)
 318       return;
 319
 320   add_undo( editor, undo_potential_end_transaction );
 321 }
 322
 323 static void ME_PlayUndoItem(ME_TextEditor *editor, struct undo_item *undo)
 324 {
 325
 326   if (editor->nUndoMode == umIgnore)
 327     return;
 328   TRACE("Playing undo/redo item, id=%d\n", undo->type);
 329
 330   switch(undo->type)
 331   {
 332   case undo_potential_end_transaction:
 333   case undo_end_transaction:
 334     assert(0);
 335   case undo_set_para_fmt:
 336   {
 337     ME_Cursor tmp;
 338     ME_DisplayItem *para;
 339     ME_CursorFromCharOfs(editor, undo->u.set_para_fmt.pos, &tmp);
 340     para = ME_FindItemBack(tmp.pRun, diParagraph);
 341     add_undo_set_para_fmt( editor, &para->member.para );
 342     *para->member.para.pFmt = undo->u.set_para_fmt.fmt;
 343     para->member.para.border = undo->u.set_para_fmt.border;
 344     para->member.para.nFlags |= MEPF_REWRAP;
 345     break;
 346   }
 347   case undo_set_char_fmt:
 348   {
 349     ME_Cursor start, end;
 350     ME_CursorFromCharOfs(editor, undo->u.set_char_fmt.pos, &start);
 351     end = start;
 352     ME_MoveCursorChars(editor, &end, undo->u.set_char_fmt.len);
 353     ME_SetCharFormat(editor, &start, &end, &undo->u.set_char_fmt.fmt);
 354     break;
 355   }
 356   case undo_insert_run:
 357   {
 358     ME_Cursor tmp;
 359     ME_CursorFromCharOfs(editor, undo->u.insert_run.pos, &tmp);
 360     ME_InsertRunAtCursor(editor, &tmp, undo->u.insert_run.style,
 361                          undo->u.insert_run.str,
 362                          undo->u.insert_run.len,
 363                          undo->u.insert_run.flags);
 364     break;
 365   }
 366   case undo_delete_run:
 367   {
 368     ME_Cursor tmp;
 369     ME_CursorFromCharOfs(editor, undo->u.delete_run.pos, &tmp);
 370     ME_InternalDeleteText(editor, &tmp, undo->u.delete_run.len, TRUE);
 371     break;
 372   }
 373   case undo_join_paras:
 374   {
 375     ME_Cursor tmp;
 376     ME_CursorFromCharOfs(editor, undo->u.join_paras.pos, &tmp);
 377     ME_JoinParagraphs(editor, tmp.pPara, TRUE);
 378     break;
 379   }
 380   case undo_split_para:
 381   {
 382     ME_Cursor tmp;
 383     ME_DisplayItem *this_para, *new_para;
 384     BOOL bFixRowStart;
 385     int paraFlags = undo->u.split_para.flags & (MEPF_ROWSTART|MEPF_CELL|MEPF_ROWEND);
 386     ME_CursorFromCharOfs(editor, undo->u.split_para.pos, &tmp);
 387     if (tmp.nOffset)
 388       ME_SplitRunSimple(editor, &tmp);
 389     this_para = tmp.pPara;
 390     bFixRowStart = this_para->member.para.nFlags & MEPF_ROWSTART;
 391     if (bFixRowStart)
 392     {
 393       /* Re-insert the paragraph before the table, making sure the nFlag value
 394        * is correct. */
 395       this_para->member.para.nFlags &= ~MEPF_ROWSTART;
 396     }
 397     new_para = ME_SplitParagraph(editor, tmp.pRun, tmp.pRun->member.run.style,
 398                                  undo->u.split_para.eol_str->szData, undo->u.split_para.eol_str->nLen, paraFlags);
 399     if (bFixRowStart)
 400       new_para->member.para.nFlags |= MEPF_ROWSTART;
 401     *new_para->member.para.pFmt = undo->u.split_para.fmt;
 402     new_para->member.para.border = undo->u.split_para.border;
 403     if (paraFlags)
 404     {
 405       ME_DisplayItem *pCell = new_para->member.para.pCell;
 406       pCell->member.cell.nRightBoundary = undo->u.split_para.cell_right_boundary;
 407       pCell->member.cell.border = undo->u.split_para.cell_border;
 408     }
 409     break;
 410   }
 411   }
 412 }
 413
 414 BOOL ME_Undo(ME_TextEditor *editor)
 415 {
 416   ME_UndoMode nMode = editor->nUndoMode;
 417   struct list *head;
 418   struct undo_item *undo, *cursor2;
 419
 420   if (editor->nUndoMode == umIgnore) return FALSE;
 421   assert(nMode == umAddToUndo || nMode == umIgnore);
 422
 423   head = list_head( &editor->undo_stack );
 424   if (!head) return FALSE;
 425
 426   /* watch out for uncommitted transactions ! */
 427   undo = LIST_ENTRY( head, struct undo_item, entry );
 428   assert(undo->type == undo_end_transaction
 429         || undo->type == undo_potential_end_transaction);
 430
 431   editor->nUndoMode = umAddToRedo;
 432
 433   list_remove( &undo->entry );
 434   destroy_undo_item( undo );
 435
 436   LIST_FOR_EACH_ENTRY_SAFE( undo, cursor2, &editor->undo_stack, struct undo_item, entry )
 437   {
 438       if (undo->type == undo_end_transaction) break;
 439       ME_PlayUndoItem( editor, undo );
 440       list_remove( &undo->entry );
 441       destroy_undo_item( undo );
 442   }
 443
 444   ME_MoveCursorFromTableRowStartParagraph(editor);
 445   add_undo( editor, undo_end_transaction );
 446   ME_CheckTablesForCorruption(editor);
 447   editor->nUndoStackSize--;
 448   editor->nUndoMode = nMode;
 449   ME_UpdateRepaint(editor, FALSE);
 450   return TRUE;
 451 }
 452
 453 BOOL ME_Redo(ME_TextEditor *editor)
 454 {
 455   ME_UndoMode nMode = editor->nUndoMode;
 456   struct list *head;
 457   struct undo_item *undo, *cursor2;
 458
 459   assert(nMode == umAddToUndo || nMode == umIgnore);
 460
 461   if (editor->nUndoMode == umIgnore) return FALSE;
 462
 463   head = list_head( &editor->redo_stack );
 464   if (!head) return FALSE;
 465
 466   /* watch out for uncommitted transactions ! */
 467   undo = LIST_ENTRY( head, struct undo_item, entry );
 468   assert( undo->type == undo_end_transaction );
 469
 470   editor->nUndoMode = umAddBackToUndo;
 471   list_remove( &undo->entry );
 472   destroy_undo_item( undo );
 473
 474   LIST_FOR_EACH_ENTRY_SAFE( undo, cursor2, &editor->redo_stack, struct undo_item, entry )
 475   {
 476       if (undo->type == undo_end_transaction) break;
 477       ME_PlayUndoItem( editor, undo );
 478       list_remove( &undo->entry );
 479       destroy_undo_item( undo );
 480   }
 481   ME_MoveCursorFromTableRowStartParagraph(editor);
 482   add_undo( editor, undo_end_transaction );
 483   ME_CheckTablesForCorruption(editor);
 484   editor->nUndoMode = nMode;
 485   ME_UpdateRepaint(editor, FALSE);
 486   return TRUE;
 487 }