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 void ME_EmptyUndoStack(ME_TextEditor *editor)
  26 {
  27   ME_DisplayItem *p, *pNext;
  28
  29   if (editor->nUndoMode == umIgnore)
  30     return;
  31
  32   TRACE("Emptying undo stack\n");
  33
  34   p = editor->pUndoStack;
  35   editor->pUndoStack = editor->pUndoStackBottom = NULL;
  36   editor->nUndoStackSize = 0;
  37   while(p) {
  38     pNext = p->next;
  39     ME_DestroyDisplayItem(p);
  40     p = pNext;
  41   }
  42   p = editor->pRedoStack;
  43   editor->pRedoStack = NULL;
  44   while(p) {
  45     pNext = p->next;
  46     ME_DestroyDisplayItem(p);
  47     p = pNext;
  48   }
  49 }
  50
  51 ME_UndoItem *ME_AddUndoItem(ME_TextEditor *editor, ME_DIType type, const ME_DisplayItem *pdi) {
  52   if (editor->nUndoMode == umIgnore)
  53     return NULL;
  54   else if (editor->nUndoLimit == 0)
  55     return NULL;
  56   else
  57   {
  58     ME_DisplayItem *pItem = ALLOC_OBJ(ME_UndoItem);
  59     switch(type)
  60     {
  61     case diUndoPotentialEndTransaction:
  62         /* only should be added for manually typed chars, not undos or redos */
  63         assert(editor->nUndoMode == umAddToUndo);
  64         /* intentional fall-through to next case */
  65     case diUndoEndTransaction:
  66       break;
  67     case diUndoSetParagraphFormat:
  68       assert(pdi);
  69       pItem->member.para = pdi->member.para;
  70       pItem->member.para.pFmt = ALLOC_OBJ(PARAFORMAT2);
  71       *pItem->member.para.pFmt = *pdi->member.para.pFmt;
  72       break;
  73     case diUndoInsertRun:
  74       assert(pdi);
  75       pItem->member.run = pdi->member.run;
  76       pItem->member.run.strText = ME_StrDup(pItem->member.run.strText);
  77       ME_AddRefStyle(pItem->member.run.style);
  78       if (pdi->member.run.ole_obj)
  79       {
  80         pItem->member.run.ole_obj = ALLOC_OBJ(*pItem->member.run.ole_obj);
  81         ME_CopyReObject(pItem->member.run.ole_obj, pdi->member.run.ole_obj);
  82       }
  83       else pItem->member.run.ole_obj = NULL;
  84       break;
  85     case diUndoSetCharFormat:
  86       break;
  87     case diUndoDeleteRun:
  88     case diUndoJoinParagraphs:
  89       break;
  90     case diUndoSplitParagraph:
  91     {
  92       ME_DisplayItem *prev_para = pdi->member.para.prev_para;
  93       assert(pdi->member.para.pFmt->cbSize == sizeof(PARAFORMAT2));
  94       pItem->member.para.pFmt = ALLOC_OBJ(PARAFORMAT2);
  95       pItem->member.para.pFmt->cbSize = sizeof(PARAFORMAT2);
  96       pItem->member.para.pFmt->dwMask = 0;
  97       *pItem->member.para.pFmt = *pdi->member.para.pFmt;
  98       pItem->member.para.border = pdi->member.para.border;
  99       pItem->member.para.nFlags = prev_para->member.para.nFlags & ~MEPF_CELL;
 100       pItem->member.para.pCell = NULL;
 101       break;
 102     }
 103     default:
 104       assert(0 == "AddUndoItem, unsupported item type");
 105       return NULL;
 106     }
 107     pItem->type = type;
 108     pItem->prev = NULL;
 109     if (editor->nUndoMode == umAddToUndo || editor->nUndoMode == umAddBackToUndo)
 110     {
 111       if (editor->pUndoStack
 112           && editor->pUndoStack->type == diUndoPotentialEndTransaction)
 113       {
 114           editor->pUndoStack->type = diUndoEndTransaction;
 115       }
 116       if (editor->nUndoMode == umAddToUndo)
 117         TRACE("Pushing id=%s to undo stack, deleting redo stack\n", ME_GetDITypeName(type));
 118       else
 119         TRACE("Pushing id=%s to undo stack\n", ME_GetDITypeName(type));
 120
 121       pItem->next = editor->pUndoStack;
 122       if (type == diUndoEndTransaction || type == diUndoPotentialEndTransaction)
 123         editor->nUndoStackSize++;
 124       if (editor->pUndoStack)
 125         editor->pUndoStack->prev = pItem;
 126       else
 127         editor->pUndoStackBottom = pItem;
 128       editor->pUndoStack = pItem;
 129
 130       if (editor->nUndoStackSize > editor->nUndoLimit)
 131       { /* remove oldest undo from stack */
 132         ME_DisplayItem *p = editor->pUndoStackBottom;
 133         while (p->type !=diUndoEndTransaction)
 134           p = p->prev; /*find new stack bottom */
 135         editor->pUndoStackBottom = p->prev;
 136           editor->pUndoStackBottom->next = NULL;
 137         do
 138         {
 139           ME_DisplayItem *pp = p->next;
 140           ME_DestroyDisplayItem(p);
 141           p = pp;
 142         } while (p);
 143         editor->nUndoStackSize--;
 144       }
 145       /* any new operation (not redo) clears the redo stack */
 146       if (editor->nUndoMode == umAddToUndo) {
 147         ME_DisplayItem *p = editor->pRedoStack;
 148         while(p)
 149         {
 150           ME_DisplayItem *pp = p->next;
 151           ME_DestroyDisplayItem(p);
 152           p = pp;
 153         }
 154         editor->pRedoStack = NULL;
 155       }
 156     }
 157     else if (editor->nUndoMode == umAddToRedo)
 158     {
 159       TRACE("Pushing id=%s to redo stack\n", ME_GetDITypeName(type));
 160       pItem->next = editor->pRedoStack;
 161       if (editor->pRedoStack)
 162         editor->pRedoStack->prev = pItem;
 163       editor->pRedoStack = pItem;
 164     }
 165     else
 166       assert(0);
 167     return (ME_UndoItem *)pItem;
 168   }
 169 }
 170
 171 /**
 172  * Commits preceding changes into a transaction that can be undone together.
 173  *
 174  * This should be called after all the changes occur associated with an event
 175  * so that the group of changes can be undone atomically as a transaction.
 176  *
 177  * This will have no effect the undo mode is set to ignore changes, or if no
 178  * changes preceded calling this function before the last time it was called.
 179  *
 180  * This can also be used to conclude a coalescing transaction (used for grouping
 181  * typed characters).
 182  */
 183 void ME_CommitUndo(ME_TextEditor *editor) {
 184   if (editor->nUndoMode == umIgnore)
 185     return;
 186
 187   assert(editor->nUndoMode == umAddToUndo);
 188
 189   /* no transactions, no need to commit */
 190   if (!editor->pUndoStack)
 191     return;
 192
 193   /* no need to commit empty transactions */
 194   if (editor->pUndoStack->type == diUndoEndTransaction)
 195     return;
 196
 197   if (editor->pUndoStack->type == diUndoPotentialEndTransaction)
 198   {
 199       /* Previous transaction was as a result of characters typed,
 200        * so the end of this transaction is confirmed. */
 201       editor->pUndoStack->type = diUndoEndTransaction;
 202       return;
 203   }
 204
 205   ME_AddUndoItem(editor, diUndoEndTransaction, NULL);
 206 }
 207
 208 /**
 209  * Groups subsequent changes with previous ones for an undo if coalescing.
 210  *
 211  * Has no effect if the previous changes were followed by a ME_CommitUndo. This
 212  * function will only have an affect if the previous changes were followed by
 213  * a call to ME_CommitCoalescingUndo, which allows the transaction to be
 214  * continued.
 215  *
 216  * This allows multiple consecutively typed characters to be grouped together
 217  * to be undone by a single undo operation.
 218  */
 219 void ME_ContinueCoalescingTransaction(ME_TextEditor *editor)
 220 {
 221   ME_DisplayItem* p;
 222
 223   if (editor->nUndoMode == umIgnore)
 224     return;
 225
 226   assert(editor->nUndoMode == umAddToUndo);
 227
 228   p = editor->pUndoStack;
 229
 230   if (p && p->type == diUndoPotentialEndTransaction) {
 231     assert(p->next); /* EndTransactions shouldn't be at bottom of undo stack */
 232     editor->pUndoStack = p->next;
 233     editor->pUndoStack->prev = NULL;
 234     editor->nUndoStackSize--;
 235     ME_DestroyDisplayItem(p);
 236   }
 237 }
 238
 239 /**
 240  * Commits preceding changes into a undo transaction that can be expanded.
 241  *
 242  * This function allows the transaction to be reopened with
 243  * ME_ContinueCoalescingTransaction in order to continue the transaction.  If an
 244  * undo item is added to the undo stack as a result of a change without the
 245  * transaction being reopened, then the transaction will be ended, and the
 246  * changes will become a part of the next transaction.
 247  *
 248  * This is used to allow typed characters to be grouped together since each
 249  * typed character results in a single event, and each event adding undo items
 250  * must be committed.  Using this function as opposed to ME_CommitUndo allows
 251  * multiple events to be grouped, and undone together.
 252  */
 253 void ME_CommitCoalescingUndo(ME_TextEditor *editor)
 254 {
 255   if (editor->nUndoMode == umIgnore)
 256     return;
 257
 258   assert(editor->nUndoMode == umAddToUndo);
 259
 260   /* no transactions, no need to commit */
 261   if (!editor->pUndoStack)
 262     return;
 263
 264   /* no need to commit empty transactions */
 265   if (editor->pUndoStack->type == diUndoEndTransaction)
 266     return;
 267   if (editor->pUndoStack->type == diUndoPotentialEndTransaction)
 268     return;
 269
 270   ME_AddUndoItem(editor, diUndoPotentialEndTransaction, NULL);
 271 }
 272
 273 static void ME_PlayUndoItem(ME_TextEditor *editor, ME_DisplayItem *pItem)
 274 {
 275   ME_UndoItem *pUItem = (ME_UndoItem *)pItem;
 276
 277   if (editor->nUndoMode == umIgnore)
 278     return;
 279   TRACE("Playing undo/redo item, id=%s\n", ME_GetDITypeName(pItem->type));
 280
 281   switch(pItem->type)
 282   {
 283   case diUndoPotentialEndTransaction:
 284   case diUndoEndTransaction:
 285     assert(0);
 286   case diUndoSetParagraphFormat:
 287   {
 288     ME_Cursor tmp;
 289     ME_DisplayItem *para;
 290     ME_CursorFromCharOfs(editor, pItem->member.para.nCharOfs, &tmp);
 291     para = ME_FindItemBack(tmp.pRun, diParagraph);
 292     ME_AddUndoItem(editor, diUndoSetParagraphFormat, para);
 293     *para->member.para.pFmt = *pItem->member.para.pFmt;
 294     para->member.para.border = pItem->member.para.border;
 295     break;
 296   }
 297   case diUndoSetCharFormat:
 298   {
 299     ME_Cursor start, end;
 300     ME_CursorFromCharOfs(editor, pUItem->nStart, &start);
 301     end = start;
 302     ME_MoveCursorChars(editor, &end, pUItem->nLen);
 303     ME_SetCharFormat(editor, &start, &end, &pItem->member.ustyle->fmt);
 304     break;
 305   }
 306   case diUndoInsertRun:
 307   {
 308     ME_Cursor tmp;
 309     ME_CursorFromCharOfs(editor, pItem->member.run.nCharOfs, &tmp);
 310     ME_InsertRunAtCursor(editor, &tmp, pItem->member.run.style,
 311                          pItem->member.run.strText->szData,
 312                          pItem->member.run.strText->nLen,
 313                          pItem->member.run.nFlags);
 314     break;
 315   }
 316   case diUndoDeleteRun:
 317   {
 318     ME_Cursor tmp;
 319     ME_CursorFromCharOfs(editor, pUItem->nStart, &tmp);
 320     ME_InternalDeleteText(editor, &tmp, pUItem->nLen, TRUE);
 321     break;
 322   }
 323   case diUndoJoinParagraphs:
 324   {
 325     ME_Cursor tmp;
 326     ME_CursorFromCharOfs(editor, pUItem->nStart, &tmp);
 327     /* the only thing that's needed is paragraph offset, so no need to split runs */
 328     ME_JoinParagraphs(editor, tmp.pPara, TRUE);
 329     break;
 330   }
 331   case diUndoSplitParagraph:
 332   {
 333     ME_Cursor tmp;
 334     ME_DisplayItem *this_para, *new_para;
 335     BOOL bFixRowStart;
 336     int paraFlags = pItem->member.para.nFlags & (MEPF_ROWSTART|MEPF_CELL|MEPF_ROWEND);
 337     ME_CursorFromCharOfs(editor, pUItem->nStart, &tmp);
 338     if (tmp.nOffset)
 339       ME_SplitRunSimple(editor, &tmp);
 340     assert(pUItem->eol_str);
 341     this_para = tmp.pPara;
 342     bFixRowStart = this_para->member.para.nFlags & MEPF_ROWSTART;
 343     if (bFixRowStart)
 344     {
 345       /* Re-insert the paragraph before the table, making sure the nFlag value
 346        * is correct. */
 347       this_para->member.para.nFlags &= ~MEPF_ROWSTART;
 348     }
 349     new_para = ME_SplitParagraph(editor, tmp.pRun, tmp.pRun->member.run.style,
 350                                  pUItem->eol_str, paraFlags);
 351     if (bFixRowStart)
 352       new_para->member.para.nFlags |= MEPF_ROWSTART;
 353     assert(pItem->member.para.pFmt->cbSize == sizeof(PARAFORMAT2));
 354     *new_para->member.para.pFmt = *pItem->member.para.pFmt;
 355     new_para->member.para.border = pItem->member.para.border;
 356     if (pItem->member.para.pCell)
 357     {
 358       ME_DisplayItem *pItemCell, *pCell;
 359       pItemCell = pItem->member.para.pCell;
 360       pCell = new_para->member.para.pCell;
 361       pCell->member.cell.nRightBoundary = pItemCell->member.cell.nRightBoundary;
 362       pCell->member.cell.border = pItemCell->member.cell.border;
 363     }
 364     break;
 365   }
 366   default:
 367     assert(0 == "PlayUndoItem, unexpected type");
 368   }
 369 }
 370
 371 BOOL ME_Undo(ME_TextEditor *editor) {
 372   ME_DisplayItem *p;
 373   ME_UndoMode nMode = editor->nUndoMode;
 374
 375   if (editor->nUndoMode == umIgnore)
 376     return FALSE;
 377   assert(nMode == umAddToUndo || nMode == umIgnore);
 378
 379   /* no undo items ? */
 380   if (!editor->pUndoStack)
 381     return FALSE;
 382
 383   /* watch out for uncommitted transactions ! */
 384   assert(editor->pUndoStack->type == diUndoEndTransaction
 385         || editor->pUndoStack->type == diUndoPotentialEndTransaction);
 386
 387   editor->nUndoMode = umAddToRedo;
 388   p = editor->pUndoStack->next;
 389   ME_DestroyDisplayItem(editor->pUndoStack);
 390   editor->pUndoStack = p;
 391   do {
 392     p->prev = NULL;
 393     ME_PlayUndoItem(editor, p);
 394     editor->pUndoStack = p->next;
 395     ME_DestroyDisplayItem(p);
 396     p = editor->pUndoStack;
 397   } while(p && p->type != diUndoEndTransaction);
 398   if (p)
 399     p->prev = NULL;
 400   ME_MoveCursorFromTableRowStartParagraph(editor);
 401   ME_AddUndoItem(editor, diUndoEndTransaction, NULL);
 402   ME_CheckTablesForCorruption(editor);
 403   editor->nUndoStackSize--;
 404   editor->nUndoMode = nMode;
 405   ME_UpdateRepaint(editor, FALSE);
 406   return TRUE;
 407 }
 408
 409 BOOL ME_Redo(ME_TextEditor *editor) {
 410   ME_DisplayItem *p;
 411   ME_UndoMode nMode = editor->nUndoMode;
 412
 413   assert(nMode == umAddToUndo || nMode == umIgnore);
 414
 415   if (editor->nUndoMode == umIgnore)
 416     return FALSE;
 417   /* no redo items ? */
 418   if (!editor->pRedoStack)
 419     return FALSE;
 420
 421   /* watch out for uncommitted transactions ! */
 422   assert(editor->pRedoStack->type == diUndoEndTransaction);
 423
 424   editor->nUndoMode = umAddBackToUndo;
 425   p = editor->pRedoStack->next;
 426   ME_DestroyDisplayItem(editor->pRedoStack);
 427   editor->pRedoStack = p;
 428   do {
 429     p->prev = NULL;
 430     ME_PlayUndoItem(editor, p);
 431     editor->pRedoStack = p->next;
 432     ME_DestroyDisplayItem(p);
 433     p = editor->pRedoStack;
 434   } while(p && p->type != diUndoEndTransaction);
 435   if (p)
 436     p->prev = NULL;
 437   ME_MoveCursorFromTableRowStartParagraph(editor);
 438   ME_AddUndoItem(editor, diUndoEndTransaction, NULL);
 439   ME_CheckTablesForCorruption(editor);
 440   editor->nUndoMode = nMode;
 441   ME_UpdateRepaint(editor, FALSE);
 442   return TRUE;
 443 }