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 = (ME_DisplayItem *)ALLOC_OBJ(ME_UndoItem);
  59     ((ME_UndoItem *)pItem)->nCR = ((ME_UndoItem *)pItem)->nLF = -1;
  60     switch(type)
  61     {
  62     case diUndoPotentialEndTransaction:
  63         /* only should be added for manually typed chars, not undos or redos */
  64         assert(editor->nUndoMode == umAddToUndo);
  65         /* intentional fall-through to next case */
  66     case diUndoEndTransaction:
  67       break;
  68     case diUndoSetParagraphFormat:
  69       assert(pdi);
  70       pItem->member.para = pdi->member.para;
  71       pItem->member.para.pFmt = ALLOC_OBJ(PARAFORMAT2);
  72       *pItem->member.para.pFmt = *pdi->member.para.pFmt;
  73       break;
  74     case diUndoInsertRun:
  75       assert(pdi);
  76       pItem->member.run = pdi->member.run;
  77       pItem->member.run.strText = ME_StrDup(pItem->member.run.strText);
  78       ME_AddRefStyle(pItem->member.run.style);
  79       if (pdi->member.run.ole_obj)
  80       {
  81         pItem->member.run.ole_obj = ALLOC_OBJ(*pItem->member.run.ole_obj);
  82         ME_CopyReObject(pItem->member.run.ole_obj, pdi->member.run.ole_obj);
  83       }
  84       else pItem->member.run.ole_obj = NULL;
  85       break;
  86     case diUndoSetCharFormat:
  87       break;
  88     case diUndoDeleteRun:
  89     case diUndoJoinParagraphs:
  90       break;
  91     case diUndoSplitParagraph:
  92     {
  93       ME_DisplayItem *prev_para = pdi->member.para.prev_para;
  94       assert(pdi->member.para.pFmt->cbSize == sizeof(PARAFORMAT2));
  95       pItem->member.para.pFmt = ALLOC_OBJ(PARAFORMAT2);
  96       pItem->member.para.pFmt->cbSize = sizeof(PARAFORMAT2);
  97       pItem->member.para.pFmt->dwMask = 0;
  98       *pItem->member.para.pFmt = *pdi->member.para.pFmt;
  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   ME_SendSelChange(editor);
 207 }
 208
 209 /**
 210  * Groups supsequent changes with previous ones for an undo if coalescing.
 211  *
 212  * Has no effect if the previous changes were followed by a ME_CommitUndo. This
 213  * function will only have an affect if the previous changes were followed by
 214  * a call to ME_CommitCoalescingUndo, which allows the transaction to be
 215  * continued.
 216  *
 217  * This allows multiple consecutively typed characters to be grouped together
 218  * to be undone by a single undo operation.
 219  */
 220 void ME_ContinueCoalescingTransaction(ME_TextEditor *editor)
 221 {
 222   ME_DisplayItem* p;
 223
 224   if (editor->nUndoMode == umIgnore)
 225     return;
 226
 227   assert(editor->nUndoMode == umAddToUndo);
 228
 229   p = editor->pUndoStack;
 230
 231   if (p && p->type == diUndoPotentialEndTransaction) {
 232     assert(p->next); /* EndTransactions shouldn't be at bottom of undo stack */
 233     editor->pUndoStack = p->next;
 234     editor->pUndoStack->prev = NULL;
 235     editor->nUndoStackSize--;
 236     ME_DestroyDisplayItem(p);
 237   }
 238 }
 239
 240 /**
 241  * Commits preceding changes into a undo transaction that can be expanded.
 242  *
 243  * This function allows the transaction to be reopened with
 244  * ME_ContinueCoalescingTransaction in order to continue the transaction.  If an
 245  * undo item is added to the undo stack as a result of a change without the
 246  * transaction being reopened, then the transaction will be ended, and the
 247  * changes will become a part of the next transaction.
 248  *
 249  * This is used to allow typed characters to be grouped together since each
 250  * typed character results in a single event, and each event adding undo items
 251  * must be committed.  Using this function as opposed to ME_CommitUndo allows
 252  * multiple events to be grouped, and undone together.
 253  */
 254 void ME_CommitCoalescingUndo(ME_TextEditor *editor)
 255 {
 256   if (editor->nUndoMode == umIgnore)
 257     return;
 258
 259   assert(editor->nUndoMode == umAddToUndo);
 260
 261   /* no transactions, no need to commit */
 262   if (!editor->pUndoStack)
 263     return;
 264
 265   /* no need to commit empty transactions */
 266   if (editor->pUndoStack->type == diUndoEndTransaction)
 267     return;
 268   if (editor->pUndoStack->type == diUndoPotentialEndTransaction)
 269     return;
 270
 271   ME_AddUndoItem(editor, diUndoPotentialEndTransaction, NULL);
 272   ME_SendSelChange(editor);
 273 }
 274
 275 static void ME_PlayUndoItem(ME_TextEditor *editor, ME_DisplayItem *pItem)
 276 {
 277   ME_UndoItem *pUItem = (ME_UndoItem *)pItem;
 278
 279   if (editor->nUndoMode == umIgnore)
 280     return;
 281   TRACE("Playing undo/redo item, id=%s\n", ME_GetDITypeName(pItem->type));
 282
 283   switch(pItem->type)
 284   {
 285   case diUndoPotentialEndTransaction:
 286   case diUndoEndTransaction:
 287     assert(0);
 288   case diUndoSetParagraphFormat:
 289   {
 290     ME_Cursor tmp;
 291     ME_DisplayItem *para;
 292     ME_CursorFromCharOfs(editor, pItem->member.para.nCharOfs, &tmp);
 293     para = ME_FindItemBack(tmp.pRun, diParagraph);
 294     ME_AddUndoItem(editor, diUndoSetParagraphFormat, para);
 295     *para->member.para.pFmt = *pItem->member.para.pFmt;
 296     break;
 297   }
 298   case diUndoSetCharFormat:
 299   {
 300     ME_SetCharFormat(editor, pUItem->nStart, pUItem->nLen, &pItem->member.ustyle->fmt);
 301     break;
 302   }
 303   case diUndoInsertRun:
 304   {
 305     ME_InsertRun(editor, pItem->member.run.nCharOfs, pItem);
 306     break;
 307   }
 308   case diUndoDeleteRun:
 309   {
 310     ME_InternalDeleteText(editor, pUItem->nStart, pUItem->nLen, TRUE);
 311     break;
 312   }
 313   case diUndoJoinParagraphs:
 314   {
 315     ME_Cursor tmp;
 316     ME_CursorFromCharOfs(editor, pUItem->nStart, &tmp);
 317     /* the only thing that's needed is paragraph offset, so no need to split runs */
 318     ME_JoinParagraphs(editor, ME_GetParagraph(tmp.pRun), TRUE);
 319     break;
 320   }
 321   case diUndoSplitParagraph:
 322   {
 323     ME_Cursor tmp;
 324     ME_DisplayItem *this_para, *new_para;
 325     BOOL bFixRowStart;
 326     int paraFlags = pItem->member.para.nFlags & (MEPF_ROWSTART|MEPF_CELL|MEPF_ROWEND);
 327     ME_CursorFromCharOfs(editor, pUItem->nStart, &tmp);
 328     if (tmp.nOffset)
 329       tmp.pRun = ME_SplitRunSimple(editor, tmp.pRun, tmp.nOffset);
 330     assert(pUItem->nCR >= 0);
 331     assert(pUItem->nLF >= 0);
 332     this_para = ME_GetParagraph(tmp.pRun);
 333     bFixRowStart = this_para->member.para.nFlags & MEPF_ROWSTART;
 334     if (bFixRowStart)
 335     {
 336       /* Re-insert the paragraph before the table, making sure the nFlag value
 337        * is correct. */
 338       this_para->member.para.nFlags &= ~MEPF_ROWSTART;
 339     }
 340     new_para = ME_SplitParagraph(editor, tmp.pRun, tmp.pRun->member.run.style,
 341                                  pUItem->nCR, pUItem->nLF, paraFlags);
 342     if (bFixRowStart)
 343       new_para->member.para.nFlags |= MEPF_ROWSTART;
 344     assert(pItem->member.para.pFmt->cbSize == sizeof(PARAFORMAT2));
 345     *new_para->member.para.pFmt = *pItem->member.para.pFmt;
 346     if (pItem->member.para.pCell)
 347     {
 348       ME_DisplayItem *pItemCell, *pCell;
 349       pItemCell = pItem->member.para.pCell;
 350       pCell = new_para->member.para.pCell;
 351       pCell->member.cell.nRightBoundary = pItemCell->member.cell.nRightBoundary;
 352     }
 353     break;
 354   }
 355   default:
 356     assert(0 == "PlayUndoItem, unexpected type");
 357   }
 358 }
 359
 360 BOOL ME_Undo(ME_TextEditor *editor) {
 361   ME_DisplayItem *p;
 362   ME_UndoMode nMode = editor->nUndoMode;
 363
 364   if (editor->nUndoMode == umIgnore)
 365     return FALSE;
 366   assert(nMode == umAddToUndo || nMode == umIgnore);
 367
 368   /* no undo items ? */
 369   if (!editor->pUndoStack)
 370     return FALSE;
 371
 372   /* watch out for uncommitted transactions ! */
 373   assert(editor->pUndoStack->type == diUndoEndTransaction
 374         || editor->pUndoStack->type == diUndoPotentialEndTransaction);
 375
 376   editor->nUndoMode = umAddToRedo;
 377   p = editor->pUndoStack->next;
 378   ME_DestroyDisplayItem(editor->pUndoStack);
 379   editor->pUndoStack = p;
 380   do {
 381     p->prev = NULL;
 382     ME_PlayUndoItem(editor, p);
 383     editor->pUndoStack = p->next;
 384     ME_DestroyDisplayItem(p);
 385     p = editor->pUndoStack;
 386   } while(p && p->type != diUndoEndTransaction);
 387   if (p)
 388     p->prev = NULL;
 389   ME_MoveCursorFromTableRowStartParagraph(editor);
 390   ME_AddUndoItem(editor, diUndoEndTransaction, NULL);
 391   ME_CheckTablesForCorruption(editor);
 392   editor->nUndoStackSize--;
 393   editor->nUndoMode = nMode;
 394   ME_UpdateRepaint(editor);
 395   return TRUE;
 396 }
 397
 398 BOOL ME_Redo(ME_TextEditor *editor) {
 399   ME_DisplayItem *p;
 400   ME_UndoMode nMode = editor->nUndoMode;
 401
 402   assert(nMode == umAddToUndo || nMode == umIgnore);
 403
 404   if (editor->nUndoMode == umIgnore)
 405     return FALSE;
 406   /* no redo items ? */
 407   if (!editor->pRedoStack)
 408     return FALSE;
 409
 410   /* watch out for uncommitted transactions ! */
 411   assert(editor->pRedoStack->type == diUndoEndTransaction);
 412
 413   editor->nUndoMode = umAddBackToUndo;
 414   p = editor->pRedoStack->next;
 415   ME_DestroyDisplayItem(editor->pRedoStack);
 416   editor->pRedoStack = p;
 417   do {
 418     p->prev = NULL;
 419     ME_PlayUndoItem(editor, p);
 420     editor->pRedoStack = p->next;
 421     ME_DestroyDisplayItem(p);
 422     p = editor->pRedoStack;
 423   } while(p && p->type != diUndoEndTransaction);
 424   if (p)
 425     p->prev = NULL;
 426   ME_MoveCursorFromTableRowStartParagraph(editor);
 427   ME_AddUndoItem(editor, diUndoEndTransaction, NULL);
 428   ME_CheckTablesForCorruption(editor);
 429   editor->nUndoMode = nMode;
 430   ME_UpdateRepaint(editor);
 431   return TRUE;
 432 }