reactos/dll/win32/riched20/caret.c

   1 /*
   2  * RichEdit - Caret and selection functions.
   3  *
   4  * Copyright 2004 by Krzysztof Foltman
   5  * Copyright 2005 by Phil Krylov
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 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  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  20  */
  21
  22
  23 #include "editor.h"
  24
  25 WINE_DEFAULT_DEBUG_CHANNEL(richedit);
  26
  27 void ME_SetCursorToStart(ME_TextEditor *editor, ME_Cursor *cursor)
  28 {
  29   cursor->pPara = editor->pBuffer->pFirst->member.para.next_para;
  30   cursor->pRun = ME_FindItemFwd(cursor->pPara, diRun);
  31   cursor->nOffset = 0;
  32 }
  33
  34 static void ME_SetCursorToEnd(ME_TextEditor *editor, ME_Cursor *cursor)
  35 {
  36   cursor->pPara = editor->pBuffer->pLast->member.para.prev_para;
  37   cursor->pRun = ME_FindItemBack(editor->pBuffer->pLast, diRun);
  38   cursor->nOffset = 0;
  39 }
  40
  41
  42 int ME_GetSelectionOfs(ME_TextEditor *editor, int *from, int *to)
  43 {
  44   *from = ME_GetCursorOfs(&editor->pCursors[0]);
  45   *to =   ME_GetCursorOfs(&editor->pCursors[1]);
  46
  47   if (*from > *to)
  48   {
  49     int tmp = *from;
  50     *from = *to;
  51     *to = tmp;
  52     return 1;
  53   }
  54   return 0;
  55 }
  56
  57 int ME_GetSelection(ME_TextEditor *editor, ME_Cursor **from, ME_Cursor **to)
  58 {
  59   int from_ofs = ME_GetCursorOfs( &editor->pCursors[0] );
  60   int to_ofs   = ME_GetCursorOfs( &editor->pCursors[1] );
  61   BOOL swap = (from_ofs > to_ofs);
  62
  63   if (from_ofs == to_ofs)
  64   {
  65       /* If cursor[0] is at the beginning of a run and cursor[1] at the end
  66          of the prev run then we need to swap. */
  67       if (editor->pCursors[0].nOffset < editor->pCursors[1].nOffset)
  68           swap = TRUE;
  69   }
  70
  71   if (!swap)
  72   {
  73     *from = &editor->pCursors[0];
  74     *to = &editor->pCursors[1];
  75     return 0;
  76   } else {
  77     *from = &editor->pCursors[1];
  78     *to = &editor->pCursors[0];
  79     return 1;
  80   }
  81 }
  82
  83 int ME_GetTextLength(ME_TextEditor *editor)
  84 {
  85   ME_Cursor cursor;
  86   ME_SetCursorToEnd(editor, &cursor);
  87   return ME_GetCursorOfs(&cursor);
  88 }
  89
  90
  91 int ME_GetTextLengthEx(ME_TextEditor *editor, const GETTEXTLENGTHEX *how)
  92 {
  93   int length;
  94
  95   if (how->flags & GTL_PRECISE && how->flags & GTL_CLOSE)
  96     return E_INVALIDARG;
  97   if (how->flags & GTL_NUMCHARS && how->flags & GTL_NUMBYTES)
  98     return E_INVALIDARG;
  99
 100   length = ME_GetTextLength(editor);
 101
 102   if ((editor->styleFlags & ES_MULTILINE)
 103         && (how->flags & GTL_USECRLF)
 104         && !editor->bEmulateVersion10) /* Ignore GTL_USECRLF flag in 1.0 emulation */
 105     length += editor->nParagraphs - 1;
 106
 107   if (how->flags & GTL_NUMBYTES ||
 108       (how->flags & GTL_PRECISE &&     /* GTL_PRECISE seems to imply GTL_NUMBYTES */
 109        !(how->flags & GTL_NUMCHARS)))  /* unless GTL_NUMCHARS is given */
 110   {
 111     CPINFO cpinfo;
 112
 113     if (how->codepage == 1200)
 114       return length * 2;
 115     if (how->flags & GTL_PRECISE)
 116       FIXME("GTL_PRECISE flag unsupported. Using GTL_CLOSE\n");
 117     if (GetCPInfo(how->codepage, &cpinfo))
 118       return length * cpinfo.MaxCharSize;
 119     ERR("Invalid codepage %u\n", how->codepage);
 120     return E_INVALIDARG;
 121   }
 122   return length;
 123 }
 124
 125
 126 int ME_SetSelection(ME_TextEditor *editor, int from, int to)
 127 {
 128   int selectionEnd = 0;
 129   const int len = ME_GetTextLength(editor);
 130
 131   /* all negative values are effectively the same */
 132   if (from < 0)
 133     from = -1;
 134   if (to < 0)
 135     to = -1;
 136
 137   /* select all */
 138   if (from == 0 && to == -1)
 139   {
 140     ME_SetCursorToStart(editor, &editor->pCursors[1]);
 141     ME_SetCursorToEnd(editor, &editor->pCursors[0]);
 142     editor->pCursors[0].nOffset = editor->pCursors[0].pRun->member.run.len;
 143     ME_InvalidateSelection(editor);
 144     return len + 1;
 145   }
 146
 147   /* if both values are equal and also out of bound, that means to */
 148   /* put the selection at the end of the text */
 149   if ((from == to) && (to < 0 || to > len))
 150   {
 151     selectionEnd = 1;
 152   }
 153   else
 154   {
 155     /* if from is negative and to is positive then selection is */
 156     /* deselected and caret moved to end of the current selection */
 157     if (from < 0)
 158     {
 159       int start, end;
 160       ME_GetSelectionOfs(editor, &start, &end);
 161       if (start != end)
 162       {
 163           if (end > len)
 164           {
 165               editor->pCursors[0].nOffset = 0;
 166               end --;
 167           }
 168           editor->pCursors[1] = editor->pCursors[0];
 169           ME_Repaint(editor);
 170       }
 171       return end;
 172     }
 173
 174     /* adjust to if it's a negative value */
 175     if (to < 0)
 176       to = len + 1;
 177
 178     /* flip from and to if they are reversed */
 179     if (from>to)
 180     {
 181       int tmp = from;
 182       from = to;
 183       to = tmp;
 184     }
 185
 186     /* after fiddling with the values, we find from > len && to > len */
 187     if (from > len)
 188       selectionEnd = 1;
 189     /* special case with to too big */
 190     else if (to > len)
 191       to = len + 1;
 192   }
 193
 194   if (selectionEnd)
 195   {
 196     ME_SetCursorToEnd(editor, &editor->pCursors[0]);
 197     editor->pCursors[1] = editor->pCursors[0];
 198     ME_InvalidateSelection(editor);
 199     return len;
 200   }
 201
 202   ME_CursorFromCharOfs(editor, from, &editor->pCursors[1]);
 203   editor->pCursors[0] = editor->pCursors[1];
 204   ME_MoveCursorChars(editor, &editor->pCursors[0], to - from);
 205   /* Selection is not allowed in the middle of an end paragraph run. */
 206   if (editor->pCursors[1].pRun->member.run.nFlags & MERF_ENDPARA)
 207     editor->pCursors[1].nOffset = 0;
 208   if (editor->pCursors[0].pRun->member.run.nFlags & MERF_ENDPARA)
 209   {
 210     if (to > len)
 211       editor->pCursors[0].nOffset = editor->pCursors[0].pRun->member.run.len;
 212     else
 213       editor->pCursors[0].nOffset = 0;
 214   }
 215   return to;
 216 }
 217
 218
 219 void ME_GetCursorCoordinates(ME_TextEditor *editor, ME_Cursor *pCursor,
 220                              int *x, int *y, int *height)
 221 {
 222   ME_DisplayItem *row;
 223   ME_DisplayItem *run = pCursor->pRun;
 224   ME_DisplayItem *para = pCursor->pPara;
 225   ME_DisplayItem *pSizeRun = run;
 226   ME_Context c;
 227   int run_x;
 228
 229   assert(height && x && y);
 230   assert(~para->member.para.nFlags & MEPF_REWRAP);
 231   assert(run && run->type == diRun);
 232   assert(para && para->type == diParagraph);
 233
 234   row = ME_FindItemBack(run, diStartRowOrParagraph);
 235   assert(row && row->type == diStartRow);
 236
 237   ME_InitContext(&c, editor, ITextHost_TxGetDC(editor->texthost));
 238
 239   if (!pCursor->nOffset)
 240   {
 241     ME_DisplayItem *prev = ME_FindItemBack(run, diRunOrParagraph);
 242     assert(prev);
 243     if (prev->type == diRun)
 244       pSizeRun = prev;
 245   }
 246   if (editor->bCaretAtEnd && !pCursor->nOffset &&
 247       run == ME_FindItemFwd(row, diRun))
 248   {
 249     ME_DisplayItem *tmp = ME_FindItemBack(row, diRunOrParagraph);
 250     assert(tmp);
 251     if (tmp->type == diRun)
 252     {
 253       row = ME_FindItemBack(tmp, diStartRow);
 254       pSizeRun = run = tmp;
 255       assert(run);
 256       assert(run->type == diRun);
 257     }
 258   }
 259   run_x = ME_PointFromCharContext( &c, &run->member.run, pCursor->nOffset, TRUE );
 260
 261   *height = pSizeRun->member.run.nAscent + pSizeRun->member.run.nDescent;
 262   *x = c.rcView.left + run->member.run.pt.x + run_x - editor->horz_si.nPos;
 263   *y = c.rcView.top + para->member.para.pt.y + row->member.row.nBaseline
 264        + run->member.run.pt.y - pSizeRun->member.run.nAscent
 265        - editor->vert_si.nPos;
 266   ME_DestroyContext(&c);
 267   return;
 268 }
 269
 270
 271 void
 272 ME_MoveCaret(ME_TextEditor *editor)
 273 {
 274   int x, y, height;
 275
 276   ME_GetCursorCoordinates(editor, &editor->pCursors[0], &x, &y, &height);
 277   if(editor->bHaveFocus && !ME_IsSelection(editor))
 278   {
 279     x = min(x, editor->rcFormat.right-1);
 280     ITextHost_TxCreateCaret(editor->texthost, NULL, 0, height);
 281     ITextHost_TxSetCaretPos(editor->texthost, x, y);
 282   }
 283 }
 284
 285
 286 void ME_ShowCaret(ME_TextEditor *ed)
 287 {
 288   ME_MoveCaret(ed);
 289   if(ed->bHaveFocus && !ME_IsSelection(ed))
 290     ITextHost_TxShowCaret(ed->texthost, TRUE);
 291 }
 292
 293 void ME_HideCaret(ME_TextEditor *ed)
 294 {
 295   if(!ed->bHaveFocus || ME_IsSelection(ed))
 296   {
 297     ITextHost_TxShowCaret(ed->texthost, FALSE);
 298     DestroyCaret();
 299   }
 300 }
 301
 302 BOOL ME_InternalDeleteText(ME_TextEditor *editor, ME_Cursor *start,
 303                            int nChars, BOOL bForce)
 304 {
 305   ME_Cursor c = *start;
 306   int nOfs = ME_GetCursorOfs(start), text_len = ME_GetTextLength( editor );
 307   int shift = 0;
 308   int totalChars = nChars;
 309   ME_DisplayItem *start_para;
 310   BOOL delete_all = FALSE;
 311
 312   /* Prevent deletion past last end of paragraph run. */
 313   nChars = min(nChars, text_len - nOfs);
 314   if (nChars == text_len) delete_all = TRUE;
 315   start_para = c.pPara;
 316
 317   if (!bForce)
 318   {
 319     ME_ProtectPartialTableDeletion(editor, &c, &nChars);
 320     if (nChars == 0)
 321       return FALSE;
 322   }
 323
 324   while(nChars > 0)
 325   {
 326     ME_Run *run;
 327     ME_CursorFromCharOfs(editor, nOfs+nChars, &c);
 328     if (!c.nOffset &&
 329         nOfs+nChars == (c.pRun->member.run.nCharOfs
 330                         + c.pPara->member.para.nCharOfs))
 331     {
 332       /* We aren't deleting anything in this run, so we will go back to the
 333        * last run we are deleting text in. */
 334       ME_PrevRun(&c.pPara, &c.pRun, TRUE);
 335       c.nOffset = c.pRun->member.run.len;
 336     }
 337     run = &c.pRun->member.run;
 338     if (run->nFlags & MERF_ENDPARA) {
 339       int eollen = c.pRun->member.run.len;
 340       BOOL keepFirstParaFormat;
 341
 342       if (!ME_FindItemFwd(c.pRun, diParagraph))
 343       {
 344         return TRUE;
 345       }
 346       keepFirstParaFormat = (totalChars == nChars && nChars <= eollen &&
 347                              run->nCharOfs);
 348       if (!editor->bEmulateVersion10) /* v4.1 */
 349       {
 350         ME_DisplayItem *next_para = ME_FindItemFwd(c.pRun, diParagraphOrEnd);
 351         ME_DisplayItem *this_para = next_para->member.para.prev_para;
 352
 353         /* The end of paragraph before a table row is only deleted if there
 354          * is nothing else on the line before it. */
 355         if (this_para == start_para &&
 356             next_para->member.para.nFlags & MEPF_ROWSTART)
 357         {
 358           /* If the paragraph will be empty, then it should be deleted, however
 359            * it still might have text right now which would inherit the
 360            * MEPF_STARTROW property if we joined it right now.
 361            * Instead we will delete it after the preceding text is deleted. */
 362           if (nOfs > this_para->member.para.nCharOfs) {
 363             /* Skip this end of line. */
 364             nChars -= (eollen < nChars) ? eollen : nChars;
 365             continue;
 366           }
 367           keepFirstParaFormat = TRUE;
 368         }
 369       }
 370       ME_JoinParagraphs(editor, c.pPara, keepFirstParaFormat);
 371       /* ME_SkipAndPropagateCharOffset(p->pRun, shift); */
 372       ME_CheckCharOffsets(editor);
 373       nChars -= (eollen < nChars) ? eollen : nChars;
 374       continue;
 375     }
 376     else
 377     {
 378       ME_Cursor cursor;
 379       int nCharsToDelete = min(nChars, c.nOffset);
 380       int i;
 381
 382       c.nOffset -= nCharsToDelete;
 383
 384       ME_FindItemBack(c.pRun, diParagraph)->member.para.nFlags |= MEPF_REWRAP;
 385
 386       cursor = c;
 387       /* nChars is the number of characters that should be deleted from the
 388          PRECEDING runs (these BEFORE cursor.pRun)
 389          nCharsToDelete is a number of chars to delete from THIS run */
 390       nChars -= nCharsToDelete;
 391       shift -= nCharsToDelete;
 392       TRACE("Deleting %d (remaining %d) chars at %d in %s (%d)\n",
 393         nCharsToDelete, nChars, c.nOffset,
 394         debugstr_run( run ), run->len);
 395
 396       /* nOfs is a character offset (from the start of the document
 397          to the current (deleted) run */
 398       add_undo_insert_run( editor, nOfs + nChars, get_text( run, c.nOffset ), nCharsToDelete, run->nFlags, run->style );
 399
 400       ME_StrDeleteV(run->para->text, run->nCharOfs + c.nOffset, nCharsToDelete);
 401       run->len -= nCharsToDelete;
 402       TRACE("Post deletion string: %s (%d)\n", debugstr_run( run ), run->len);
 403       TRACE("Shift value: %d\n", shift);
 404
 405       /* update cursors (including c) */
 406       for (i=-1; i<editor->nCursors; i++) {
 407         ME_Cursor *pThisCur = editor->pCursors + i;
 408         if (i == -1) pThisCur = &c;
 409         if (pThisCur->pRun == cursor.pRun) {
 410           if (pThisCur->nOffset > cursor.nOffset) {
 411             if (pThisCur->nOffset-cursor.nOffset < nCharsToDelete)
 412               pThisCur->nOffset = cursor.nOffset;
 413             else
 414               pThisCur->nOffset -= nCharsToDelete;
 415             assert(pThisCur->nOffset >= 0);
 416             assert(pThisCur->nOffset <= run->len);
 417           }
 418           if (pThisCur->nOffset == run->len)
 419           {
 420             pThisCur->pRun = ME_FindItemFwd(pThisCur->pRun, diRunOrParagraphOrEnd);
 421             assert(pThisCur->pRun->type == diRun);
 422             pThisCur->nOffset = 0;
 423           }
 424         }
 425       }
 426
 427       /* c = updated data now */
 428
 429       if (c.pRun == cursor.pRun)
 430         ME_SkipAndPropagateCharOffset(c.pRun, shift);
 431       else
 432         ME_PropagateCharOffset(c.pRun, shift);
 433
 434       if (!cursor.pRun->member.run.len)
 435       {
 436         TRACE("Removing empty run\n");
 437         ME_Remove(cursor.pRun);
 438         ME_DestroyDisplayItem(cursor.pRun);
 439       }
 440
 441       shift = 0;
 442       /*
 443       ME_CheckCharOffsets(editor);
 444       */
 445       continue;
 446     }
 447   }
 448   if (delete_all) ME_SetDefaultParaFormat( editor, start_para->member.para.pFmt );
 449   return TRUE;
 450 }
 451
 452 BOOL ME_DeleteTextAtCursor(ME_TextEditor *editor, int nCursor, int nChars)
 453 {
 454   assert(nCursor>=0 && nCursor<editor->nCursors);
 455   /* text operations set modified state */
 456   editor->nModifyStep = 1;
 457   return ME_InternalDeleteText(editor, &editor->pCursors[nCursor],
 458                                nChars, FALSE);
 459 }
 460
 461 static ME_DisplayItem *
 462 ME_InternalInsertTextFromCursor(ME_TextEditor *editor, int nCursor,
 463                                 const WCHAR *str, int len, ME_Style *style,
 464                                 int flags)
 465 {
 466   ME_Cursor *p = &editor->pCursors[nCursor];
 467
 468   editor->bCaretAtEnd = FALSE;
 469
 470   assert(p->pRun->type == diRun);
 471
 472   return ME_InsertRunAtCursor(editor, p, style, str, len, flags);
 473 }
 474
 475
 476 void ME_InsertOLEFromCursor(ME_TextEditor *editor, const REOBJECT* reo, int nCursor)
 477 {
 478   ME_Style              *pStyle = ME_GetInsertStyle(editor, nCursor);
 479   ME_DisplayItem        *di;
 480   WCHAR                 space = ' ';
 481
 482   /* FIXME no no no */
 483   if (ME_IsSelection(editor))
 484     ME_DeleteSelection(editor);
 485
 486   di = ME_InternalInsertTextFromCursor(editor, nCursor, &space, 1, pStyle,
 487                                        MERF_GRAPHICS);
 488   di->member.run.ole_obj = ALLOC_OBJ(*reo);
 489   ME_CopyReObject(di->member.run.ole_obj, reo);
 490   ME_ReleaseStyle(pStyle);
 491 }
 492
 493
 494 void ME_InsertEndRowFromCursor(ME_TextEditor *editor, int nCursor)
 495 {
 496   ME_Style              *pStyle = ME_GetInsertStyle(editor, nCursor);
 497   WCHAR                 space = ' ';
 498
 499   /* FIXME no no no */
 500   if (ME_IsSelection(editor))
 501     ME_DeleteSelection(editor);
 502
 503   ME_InternalInsertTextFromCursor(editor, nCursor, &space, 1, pStyle,
 504                                   MERF_ENDROW);
 505   ME_ReleaseStyle(pStyle);
 506 }
 507
 508
 509 void ME_InsertTextFromCursor(ME_TextEditor *editor, int nCursor,
 510   const WCHAR *str, int len, ME_Style *style)
 511 {
 512   const WCHAR *pos;
 513   ME_Cursor *p = NULL;
 514   int oldLen;
 515
 516   /* FIXME really HERE ? */
 517   if (ME_IsSelection(editor))
 518     ME_DeleteSelection(editor);
 519
 520   /* FIXME: is this too slow? */
 521   /* Didn't affect performance for WM_SETTEXT (around 50sec/30K) */
 522   oldLen = ME_GetTextLength(editor);
 523
 524   /* text operations set modified state */
 525   editor->nModifyStep = 1;
 526
 527   assert(style);
 528
 529   assert(nCursor>=0 && nCursor<editor->nCursors);
 530   if (len == -1)
 531     len = lstrlenW(str);
 532
 533   /* grow the text limit to fit our text */
 534   if(editor->nTextLimit < oldLen +len)
 535     editor->nTextLimit = oldLen + len;
 536
 537   pos = str;
 538
 539   while (len)
 540   {
 541     /* FIXME this sucks - no respect for unicode (what else can be a line separator in unicode?) */
 542     while(pos - str < len && *pos != '\r' && *pos != '\n' && *pos != '\t')
 543       pos++;
 544
 545     if (pos != str) { /* handle text */
 546       ME_InternalInsertTextFromCursor(editor, nCursor, str, pos-str, style, 0);
 547     } else if (*pos == '\t') { /* handle tabs */
 548       WCHAR tab = '\t';
 549       ME_InternalInsertTextFromCursor(editor, nCursor, &tab, 1, style, MERF_TAB);
 550       pos++;
 551     } else { /* handle EOLs */
 552       ME_DisplayItem *tp, *end_run, *run, *prev;
 553       ME_Style *tmp_style;
 554       int eol_len = 0;
 555
 556       /* Find number of CR and LF in end of paragraph run */
 557       if (*pos =='\r')
 558       {
 559         if (len > 1 && pos[1] == '\n')
 560           eol_len = 2;
 561         else if (len > 2 && pos[1] == '\r' && pos[2] == '\n')
 562           eol_len = 3;
 563         else
 564           eol_len = 1;
 565       } else {
 566         assert(*pos == '\n');
 567         eol_len = 1;
 568       }
 569       pos += eol_len;
 570
 571       if (!editor->bEmulateVersion10 && eol_len == 3)
 572       {
 573         /* handle special \r\r\n sequence (richedit 2.x and higher only) */
 574         WCHAR space = ' ';
 575         ME_InternalInsertTextFromCursor(editor, nCursor, &space, 1, style, 0);
 576       } else {
 577         const WCHAR cr = '\r', *eol_str = str;
 578
 579         if (!editor->bEmulateVersion10)
 580         {
 581           eol_str = &cr;
 582           eol_len = 1;
 583         }
 584
 585         p = &editor->pCursors[nCursor];
 586
 587         if (p->nOffset == p->pRun->member.run.len)
 588         {
 589            run = ME_FindItemFwd( p->pRun, diRun );
 590            if (!run) run = p->pRun;
 591         }
 592         else
 593         {
 594           if (p->nOffset) ME_SplitRunSimple(editor, p);
 595           run = p->pRun;
 596         }
 597
 598         tmp_style = ME_GetInsertStyle(editor, nCursor);
 599         /* ME_SplitParagraph increases style refcount */
 600         tp = ME_SplitParagraph(editor, run, run->member.run.style, eol_str, eol_len, 0);
 601
 602         end_run = ME_FindItemBack(tp, diRun);
 603         ME_ReleaseStyle(end_run->member.run.style);
 604         end_run->member.run.style = tmp_style;
 605
 606         /* Move any cursors that were at the end of the previous run to the beginning of the new para */
 607         prev = ME_FindItemBack( end_run, diRun );
 608         if (prev)
 609         {
 610           int i;
 611           for (i = 0; i < editor->nCursors; i++)
 612           {
 613             if (editor->pCursors[i].pRun == prev &&
 614                 editor->pCursors[i].nOffset == prev->member.run.len)
 615             {
 616               editor->pCursors[i].pPara = tp;
 617               editor->pCursors[i].pRun = run;
 618               editor->pCursors[i].nOffset = 0;
 619             }
 620           }
 621         }
 622
 623       }
 624     }
 625     len -= pos - str;
 626     str = pos;
 627   }
 628 }
 629
 630 /* Move the cursor nRelOfs characters (either forwards or backwards)
 631  *
 632  * returns the actual number of characters moved.
 633  **/
 634 int ME_MoveCursorChars(ME_TextEditor *editor, ME_Cursor *cursor, int nRelOfs)
 635 {
 636   cursor->nOffset += nRelOfs;
 637   if (cursor->nOffset < 0)
 638   {
 639     cursor->nOffset += cursor->pRun->member.run.nCharOfs;
 640     if (cursor->nOffset >= 0)
 641     {
 642       /* new offset in the same paragraph */
 643       do {
 644         cursor->pRun = ME_FindItemBack(cursor->pRun, diRun);
 645       } while (cursor->nOffset < cursor->pRun->member.run.nCharOfs);
 646       cursor->nOffset -= cursor->pRun->member.run.nCharOfs;
 647       return nRelOfs;
 648     }
 649
 650     cursor->nOffset += cursor->pPara->member.para.nCharOfs;
 651     if (cursor->nOffset <= 0)
 652     {
 653       /* moved to the start of the text */
 654       nRelOfs -= cursor->nOffset;
 655       ME_SetCursorToStart(editor, cursor);
 656       return nRelOfs;
 657     }
 658
 659     /* new offset in a previous paragraph */
 660     do {
 661       cursor->pPara = cursor->pPara->member.para.prev_para;
 662     } while (cursor->nOffset < cursor->pPara->member.para.nCharOfs);
 663     cursor->nOffset -= cursor->pPara->member.para.nCharOfs;
 664
 665     cursor->pRun = ME_FindItemBack(cursor->pPara->member.para.next_para, diRun);
 666     while (cursor->nOffset < cursor->pRun->member.run.nCharOfs) {
 667       cursor->pRun = ME_FindItemBack(cursor->pRun, diRun);
 668     }
 669     cursor->nOffset -= cursor->pRun->member.run.nCharOfs;
 670   } else if (cursor->nOffset >= cursor->pRun->member.run.len) {
 671     ME_DisplayItem *next_para;
 672     int new_offset;
 673
 674     new_offset = ME_GetCursorOfs(cursor);
 675     next_para = cursor->pPara->member.para.next_para;
 676     if (new_offset < next_para->member.para.nCharOfs)
 677     {
 678       /* new offset in the same paragraph */
 679       do {
 680         cursor->nOffset -= cursor->pRun->member.run.len;
 681         cursor->pRun = ME_FindItemFwd(cursor->pRun, diRun);
 682       } while (cursor->nOffset >= cursor->pRun->member.run.len);
 683       return nRelOfs;
 684     }
 685
 686     if (new_offset >= ME_GetTextLength(editor))
 687     {
 688       /* new offset at the end of the text */
 689       ME_SetCursorToEnd(editor, cursor);
 690       nRelOfs -= new_offset - ME_GetTextLength(editor);
 691       return nRelOfs;
 692     }
 693
 694     /* new offset in a following paragraph */
 695     do {
 696       cursor->pPara = next_para;
 697       next_para = next_para->member.para.next_para;
 698     } while (new_offset >= next_para->member.para.nCharOfs);
 699
 700     cursor->nOffset = new_offset - cursor->pPara->member.para.nCharOfs;
 701     cursor->pRun = ME_FindItemFwd(cursor->pPara, diRun);
 702     while (cursor->nOffset >= cursor->pRun->member.run.len)
 703     {
 704       cursor->nOffset -= cursor->pRun->member.run.len;
 705       cursor->pRun = ME_FindItemFwd(cursor->pRun, diRun);
 706     }
 707   } /* else new offset is in the same run */
 708   return nRelOfs;
 709 }
 710
 711
 712 BOOL
 713 ME_MoveCursorWords(ME_TextEditor *editor, ME_Cursor *cursor, int nRelOfs)
 714 {
 715   ME_DisplayItem *pRun = cursor->pRun, *pOtherRun;
 716   ME_DisplayItem *pPara = cursor->pPara;
 717   int nOffset = cursor->nOffset;
 718
 719   if (nRelOfs == -1)
 720   {
 721     /* Backward movement */
 722     while (TRUE)
 723     {
 724       nOffset = ME_CallWordBreakProc(editor, get_text( &pRun->member.run, 0 ),
 725                                      pRun->member.run.len, nOffset, WB_MOVEWORDLEFT);
 726       if (nOffset)
 727         break;
 728       pOtherRun = ME_FindItemBack(pRun, diRunOrParagraph);
 729       if (pOtherRun->type == diRun)
 730       {
 731         if (ME_CallWordBreakProc(editor, get_text( &pOtherRun->member.run, 0 ),
 732                                  pOtherRun->member.run.len,
 733                                  pOtherRun->member.run.len - 1,
 734                                  WB_ISDELIMITER)
 735             && !(pRun->member.run.nFlags & MERF_ENDPARA)
 736             && !(cursor->pRun == pRun && cursor->nOffset == 0)
 737             && !ME_CallWordBreakProc(editor, get_text( &pRun->member.run, 0 ),
 738                                      pRun->member.run.len, 0,
 739                                      WB_ISDELIMITER))
 740           break;
 741         pRun = pOtherRun;
 742         nOffset = pOtherRun->member.run.len;
 743       }
 744       else if (pOtherRun->type == diParagraph)
 745       {
 746         if (cursor->pRun == pRun && cursor->nOffset == 0)
 747         {
 748           pPara = pOtherRun;
 749           /* Skip empty start of table row paragraph */
 750           if (pPara->member.para.prev_para->member.para.nFlags & MEPF_ROWSTART)
 751             pPara = pPara->member.para.prev_para;
 752           /* Paragraph breaks are treated as separate words */
 753           if (pPara->member.para.prev_para->type == diTextStart)
 754             return FALSE;
 755
 756           pRun = ME_FindItemBack(pPara, diRun);
 757           pPara = pPara->member.para.prev_para;
 758         }
 759         break;
 760       }
 761     }
 762   }
 763   else
 764   {
 765     /* Forward movement */
 766     BOOL last_delim = FALSE;
 767
 768     while (TRUE)
 769     {
 770       if (last_delim && !ME_CallWordBreakProc(editor, get_text( &pRun->member.run, 0 ),
 771                                               pRun->member.run.len, nOffset, WB_ISDELIMITER))
 772         break;
 773       nOffset = ME_CallWordBreakProc(editor, get_text( &pRun->member.run, 0 ),
 774                                      pRun->member.run.len, nOffset, WB_MOVEWORDRIGHT);
 775       if (nOffset < pRun->member.run.len)
 776         break;
 777       pOtherRun = ME_FindItemFwd(pRun, diRunOrParagraphOrEnd);
 778       if (pOtherRun->type == diRun)
 779       {
 780         last_delim = ME_CallWordBreakProc(editor, get_text( &pRun->member.run, 0 ),
 781                                           pRun->member.run.len, nOffset - 1, WB_ISDELIMITER);
 782         pRun = pOtherRun;
 783         nOffset = 0;
 784       }
 785       else if (pOtherRun->type == diParagraph)
 786       {
 787         if (pOtherRun->member.para.nFlags & MEPF_ROWSTART)
 788             pOtherRun = pOtherRun->member.para.next_para;
 789         if (cursor->pRun == pRun) {
 790           pPara = pOtherRun;
 791           pRun = ME_FindItemFwd(pPara, diRun);
 792         }
 793         nOffset = 0;
 794         break;
 795       }
 796       else /* diTextEnd */
 797       {
 798         if (cursor->pRun == pRun)
 799           return FALSE;
 800         nOffset = 0;
 801         break;
 802       }
 803     }
 804   }
 805   cursor->pPara = pPara;
 806   cursor->pRun = pRun;
 807   cursor->nOffset = nOffset;
 808   return TRUE;
 809 }
 810
 811
 812 static void
 813 ME_SelectByType(ME_TextEditor *editor, ME_SelectionType selectionType)
 814 {
 815   /* pCursor[0] is the end of the selection
 816    * pCursor[1] is the start of the selection (or the position selection anchor)
 817    * pCursor[2] and [3] are the selection anchors that are backed up
 818    * so they are kept when the selection changes for drag selection.
 819    */
 820
 821   editor->nSelectionType = selectionType;
 822   switch(selectionType)
 823   {
 824     case stPosition:
 825       break;
 826     case stWord:
 827       ME_MoveCursorWords(editor, &editor->pCursors[0], +1);
 828       editor->pCursors[1] = editor->pCursors[0];
 829       ME_MoveCursorWords(editor, &editor->pCursors[1], -1);
 830       break;
 831     case stLine:
 832     case stParagraph:
 833     {
 834       ME_DisplayItem *pItem;
 835       ME_DIType fwdSearchType, backSearchType;
 836       if (selectionType == stParagraph) {
 837           backSearchType = diParagraph;
 838           fwdSearchType = diParagraphOrEnd;
 839       } else {
 840           backSearchType = diStartRow;
 841           fwdSearchType = diStartRowOrParagraphOrEnd;
 842       }
 843       pItem = ME_FindItemFwd(editor->pCursors[0].pRun, fwdSearchType);
 844       assert(pItem);
 845       if (pItem->type == diTextEnd)
 846           editor->pCursors[0].pRun = ME_FindItemBack(pItem, diRun);
 847       else
 848           editor->pCursors[0].pRun = ME_FindItemFwd(pItem, diRun);
 849       editor->pCursors[0].pPara = ME_GetParagraph(editor->pCursors[0].pRun);
 850       editor->pCursors[0].nOffset = 0;
 851
 852       pItem = ME_FindItemBack(pItem, backSearchType);
 853       editor->pCursors[1].pRun = ME_FindItemFwd(pItem, diRun);
 854       editor->pCursors[1].pPara = ME_GetParagraph(editor->pCursors[1].pRun);
 855       editor->pCursors[1].nOffset = 0;
 856       break;
 857     }
 858     case stDocument:
 859       /* Select everything with cursor anchored from the start of the text */
 860       editor->nSelectionType = stDocument;
 861       ME_SetCursorToStart(editor, &editor->pCursors[1]);
 862       ME_SetCursorToEnd(editor, &editor->pCursors[0]);
 863       break;
 864     default: assert(0);
 865   }
 866   /* Store the anchor positions for extending the selection. */
 867   editor->pCursors[2] = editor->pCursors[0];
 868   editor->pCursors[3] = editor->pCursors[1];
 869 }
 870
 871 int ME_GetCursorOfs(const ME_Cursor *cursor)
 872 {
 873   return cursor->pPara->member.para.nCharOfs
 874          + cursor->pRun->member.run.nCharOfs + cursor->nOffset;
 875 }
 876
 877 /* Helper function for ME_FindPixelPos to find paragraph within tables */
 878 static ME_DisplayItem* ME_FindPixelPosInTableRow(int x, int y,
 879                                                  ME_DisplayItem *para)
 880 {
 881   ME_DisplayItem *cell, *next_cell;
 882   assert(para->member.para.nFlags & MEPF_ROWSTART);
 883   cell = para->member.para.next_para->member.para.pCell;
 884   assert(cell);
 885
 886   /* find the cell we are in */
 887   while ((next_cell = cell->member.cell.next_cell) != NULL) {
 888     if (x < next_cell->member.cell.pt.x)
 889     {
 890       para = ME_FindItemFwd(cell, diParagraph);
 891       /* Found the cell, but there might be multiple paragraphs in
 892        * the cell, so need to search down the cell for the paragraph. */
 893       while (cell == para->member.para.pCell) {
 894         if (y < para->member.para.pt.y + para->member.para.nHeight)
 895         {
 896           if (para->member.para.nFlags & MEPF_ROWSTART)
 897             return ME_FindPixelPosInTableRow(x, y, para);
 898           else
 899             return para;
 900         }
 901         para = para->member.para.next_para;
 902       }
 903       /* Past the end of the cell, so go back to the last cell paragraph */
 904       return para->member.para.prev_para;
 905     }
 906     cell = next_cell;
 907   }
 908   /* Return table row delimiter */
 909   para = ME_FindItemFwd(cell, diParagraph);
 910   assert(para->member.para.nFlags & MEPF_ROWEND);
 911   assert(para->member.para.pFmt->dwMask & PFM_TABLEROWDELIMITER);
 912   assert(para->member.para.pFmt->wEffects & PFE_TABLEROWDELIMITER);
 913   return para;
 914 }
 915
 916 static BOOL ME_FindRunInRow(ME_TextEditor *editor, ME_DisplayItem *pRow,
 917                             int x, ME_Cursor *cursor, BOOL *pbCaretAtEnd)
 918 {
 919   ME_DisplayItem *pNext, *pLastRun;
 920   ME_Row *row = &pRow->member.row;
 921   BOOL exact = TRUE;
 922
 923   if (x < row->pt.x)
 924   {
 925       x = row->pt.x;
 926       exact = FALSE;
 927   }
 928   pNext = ME_FindItemFwd(pRow, diRunOrStartRow);
 929   assert(pNext->type == diRun);
 930   if (pbCaretAtEnd) *pbCaretAtEnd = FALSE;
 931   cursor->nOffset = 0;
 932   do {
 933     int run_x = pNext->member.run.pt.x;
 934     int width = pNext->member.run.nWidth;
 935
 936     if (x >= run_x && x < run_x+width)
 937     {
 938       cursor->nOffset = ME_CharFromPoint(editor, x-run_x, &pNext->member.run, TRUE, TRUE);
 939       cursor->pRun = pNext;
 940       cursor->pPara = ME_GetParagraph( cursor->pRun );
 941       return exact;
 942     }
 943     pLastRun = pNext;
 944     pNext = ME_FindItemFwd(pNext, diRunOrStartRow);
 945   } while(pNext && pNext->type == diRun);
 946
 947   if ((pLastRun->member.run.nFlags & MERF_ENDPARA) == 0)
 948   {
 949     cursor->pRun = ME_FindItemFwd(pNext, diRun);
 950     if (pbCaretAtEnd) *pbCaretAtEnd = TRUE;
 951   }
 952   else
 953     cursor->pRun = pLastRun;
 954
 955   cursor->pPara = ME_GetParagraph( cursor->pRun );
 956   return FALSE;
 957 }
 958
 959 /* Finds the run and offset from the pixel position.
 960  *
 961  * x & y are pixel positions in virtual coordinates into the rich edit control,
 962  * so client coordinates must first be adjusted by the scroll position.
 963  *
 964  * returns TRUE if the result was exactly under the cursor, otherwise returns
 965  * FALSE, and result is set to the closest position to the coordinates.
 966  */
 967 static BOOL ME_FindPixelPos(ME_TextEditor *editor, int x, int y,
 968                             ME_Cursor *result, BOOL *is_eol)
 969 {
 970   ME_DisplayItem *p = editor->pBuffer->pFirst->member.para.next_para;
 971   BOOL isExact = TRUE;
 972
 973   x -= editor->rcFormat.left;
 974   y -= editor->rcFormat.top;
 975
 976   if (is_eol)
 977     *is_eol = FALSE;
 978
 979   /* find paragraph */
 980   for (; p != editor->pBuffer->pLast; p = p->member.para.next_para)
 981   {
 982     assert(p->type == diParagraph);
 983     if (y < p->member.para.pt.y + p->member.para.nHeight)
 984     {
 985       if (p->member.para.nFlags & MEPF_ROWSTART)
 986         p = ME_FindPixelPosInTableRow(x, y, p);
 987       y -= p->member.para.pt.y;
 988       p = ME_FindItemFwd(p, diStartRow);
 989       break;
 990     } else if (p->member.para.nFlags & MEPF_ROWSTART) {
 991       p = ME_GetTableRowEnd(p);
 992     }
 993   }
 994   /* find row */
 995   for (; p != editor->pBuffer->pLast; )
 996   {
 997     ME_DisplayItem *pp;
 998     assert(p->type == diStartRow);
 999     if (y < p->member.row.pt.y + p->member.row.nHeight) break;
1000     pp = ME_FindItemFwd(p, diStartRow);
1001     if (!pp) break;
1002     p = pp;
1003   }
1004   if (p == editor->pBuffer->pLast)
1005   {
1006     /* The position is below the last paragraph, so the last row will be used
1007      * rather than the end of the text, so the x position will be used to
1008      * determine the offset closest to the pixel position. */
1009     isExact = FALSE;
1010     p = ME_FindItemBack(p, diStartRow);
1011     if (!p) p = editor->pBuffer->pLast;
1012   }
1013
1014   assert( p->type == diStartRow || p == editor->pBuffer->pLast );
1015
1016   if( p->type == diStartRow )
1017       return ME_FindRunInRow( editor, p, x, result, is_eol ) && isExact;
1018
1019   result->pRun = ME_FindItemBack(p, diRun);
1020   result->pPara = ME_GetParagraph(result->pRun);
1021   result->nOffset = 0;
1022   assert(result->pRun->member.run.nFlags & MERF_ENDPARA);
1023   return FALSE;
1024 }
1025
1026
1027 /* Sets the cursor to the position closest to the pixel position
1028  *
1029  * x & y are pixel positions in client coordinates.
1030  *
1031  * isExact will be set to TRUE if the run is directly under the pixel
1032  * position, FALSE if it not, unless isExact is set to NULL.
1033  *
1034  * return FALSE if outside client area and the cursor is not set,
1035  * otherwise TRUE is returned.
1036  */
1037 BOOL ME_CharFromPos(ME_TextEditor *editor, int x, int y,
1038                     ME_Cursor *cursor, BOOL *isExact)
1039 {
1040   RECT rc;
1041   BOOL bResult;
1042
1043   ITextHost_TxGetClientRect(editor->texthost, &rc);
1044   if (x < 0 || y < 0 || x >= rc.right || y >= rc.bottom) {
1045     if (isExact) *isExact = FALSE;
1046     return FALSE;
1047   }
1048   x += editor->horz_si.nPos;
1049   y += editor->vert_si.nPos;
1050   bResult = ME_FindPixelPos(editor, x, y, cursor, NULL);
1051   if (isExact) *isExact = bResult;
1052   return TRUE;
1053 }
1054
1055
1056
1057 /* Extends the selection with a word, line, or paragraph selection type.
1058  *
1059  * The selection is anchored by editor->pCursors[2-3] such that the text
1060  * between the anchors will remain selected, and one end will be extended.
1061  *
1062  * editor->pCursors[0] should have the position to extend the selection to
1063  * before this function is called.
1064  *
1065  * Nothing will be done if editor->nSelectionType equals stPosition.
1066  */
1067 static void ME_ExtendAnchorSelection(ME_TextEditor *editor)
1068 {
1069   ME_Cursor tmp_cursor;
1070   int curOfs, anchorStartOfs, anchorEndOfs;
1071   if (editor->nSelectionType == stPosition || editor->nSelectionType == stDocument)
1072       return;
1073   curOfs = ME_GetCursorOfs(&editor->pCursors[0]);
1074   anchorStartOfs = ME_GetCursorOfs(&editor->pCursors[3]);
1075   anchorEndOfs = ME_GetCursorOfs(&editor->pCursors[2]);
1076
1077   tmp_cursor = editor->pCursors[0];
1078   editor->pCursors[0] = editor->pCursors[2];
1079   editor->pCursors[1] = editor->pCursors[3];
1080   if (curOfs < anchorStartOfs)
1081   {
1082       /* Extend the left side of selection */
1083       editor->pCursors[1] = tmp_cursor;
1084       if (editor->nSelectionType == stWord)
1085           ME_MoveCursorWords(editor, &editor->pCursors[1], -1);
1086       else
1087       {
1088           ME_DisplayItem *pItem;
1089           ME_DIType searchType = ((editor->nSelectionType == stLine) ?
1090                                   diStartRowOrParagraph:diParagraph);
1091           pItem = ME_FindItemBack(editor->pCursors[1].pRun, searchType);
1092           editor->pCursors[1].pRun = ME_FindItemFwd(pItem, diRun);
1093           editor->pCursors[1].pPara = ME_GetParagraph(editor->pCursors[1].pRun);
1094           editor->pCursors[1].nOffset = 0;
1095       }
1096   }
1097   else if (curOfs >= anchorEndOfs)
1098   {
1099       /* Extend the right side of selection */
1100       editor->pCursors[0] = tmp_cursor;
1101       if (editor->nSelectionType == stWord)
1102           ME_MoveCursorWords(editor, &editor->pCursors[0], +1);
1103       else
1104       {
1105           ME_DisplayItem *pItem;
1106           ME_DIType searchType = ((editor->nSelectionType == stLine) ?
1107                                   diStartRowOrParagraphOrEnd:diParagraphOrEnd);
1108           pItem = ME_FindItemFwd(editor->pCursors[0].pRun, searchType);
1109           if (pItem->type == diTextEnd)
1110               editor->pCursors[0].pRun = ME_FindItemBack(pItem, diRun);
1111           else
1112               editor->pCursors[0].pRun = ME_FindItemFwd(pItem, diRun);
1113           editor->pCursors[0].pPara = ME_GetParagraph(editor->pCursors[0].pRun);
1114           editor->pCursors[0].nOffset = 0;
1115       }
1116   }
1117 }
1118
1119 void ME_LButtonDown(ME_TextEditor *editor, int x, int y, int clickNum)
1120 {
1121   ME_Cursor tmp_cursor;
1122   BOOL is_selection = FALSE, is_shift;
1123
1124   editor->nUDArrowX = -1;
1125
1126   x += editor->horz_si.nPos;
1127   y += editor->vert_si.nPos;
1128
1129   tmp_cursor = editor->pCursors[0];
1130   is_selection = ME_IsSelection(editor);
1131   is_shift = GetKeyState(VK_SHIFT) < 0;
1132
1133   ME_FindPixelPos(editor, x, y, &editor->pCursors[0], &editor->bCaretAtEnd);
1134
1135   if (x >= editor->rcFormat.left || is_shift)
1136   {
1137     if (clickNum > 1)
1138     {
1139       editor->pCursors[1] = editor->pCursors[0];
1140       if (is_shift) {
1141           if (x >= editor->rcFormat.left)
1142               ME_SelectByType(editor, stWord);
1143           else
1144               ME_SelectByType(editor, stParagraph);
1145       } else if (clickNum % 2 == 0) {
1146           ME_SelectByType(editor, stWord);
1147       } else {
1148           ME_SelectByType(editor, stParagraph);
1149       }
1150     }
1151     else if (!is_shift)
1152     {
1153       editor->nSelectionType = stPosition;
1154       editor->pCursors[1] = editor->pCursors[0];
1155     }
1156     else if (!is_selection)
1157     {
1158       editor->nSelectionType = stPosition;
1159       editor->pCursors[1] = tmp_cursor;
1160     }
1161     else if (editor->nSelectionType != stPosition)
1162     {
1163       ME_ExtendAnchorSelection(editor);
1164     }
1165   }
1166   else
1167   {
1168     if (clickNum < 2) {
1169         ME_SelectByType(editor, stLine);
1170     } else if (clickNum % 2 == 0 || is_shift) {
1171         ME_SelectByType(editor, stParagraph);
1172     } else {
1173         ME_SelectByType(editor, stDocument);
1174     }
1175   }
1176   ME_InvalidateSelection(editor);
1177   ITextHost_TxShowCaret(editor->texthost, FALSE);
1178   ME_ShowCaret(editor);
1179   ME_SendSelChange(editor);
1180 }
1181
1182 void ME_MouseMove(ME_TextEditor *editor, int x, int y)
1183 {
1184   ME_Cursor tmp_cursor;
1185
1186   if (editor->nSelectionType == stDocument)
1187       return;
1188   x += editor->horz_si.nPos;
1189   y += editor->vert_si.nPos;
1190
1191   tmp_cursor = editor->pCursors[0];
1192   /* FIXME: do something with the return value of ME_FindPixelPos */
1193   ME_FindPixelPos(editor, x, y, &tmp_cursor, &editor->bCaretAtEnd);
1194
1195   ME_InvalidateSelection(editor);
1196   editor->pCursors[0] = tmp_cursor;
1197   ME_ExtendAnchorSelection(editor);
1198
1199   if (editor->nSelectionType != stPosition &&
1200       memcmp(&editor->pCursors[1], &editor->pCursors[3], sizeof(ME_Cursor)))
1201   {
1202       /* The scroll the cursor towards the other end, since it was the one
1203        * extended by ME_ExtendAnchorSelection */
1204       ME_EnsureVisible(editor, &editor->pCursors[1]);
1205   } else {
1206       ME_EnsureVisible(editor, &editor->pCursors[0]);
1207   }
1208
1209   ME_InvalidateSelection(editor);
1210   ITextHost_TxShowCaret(editor->texthost, FALSE);
1211   ME_ShowCaret(editor);
1212   ME_SendSelChange(editor);
1213 }
1214
1215 static int ME_GetXForArrow(ME_TextEditor *editor, ME_Cursor *pCursor)
1216 {
1217   ME_DisplayItem *pRun = pCursor->pRun;
1218   int x;
1219
1220   if (editor->nUDArrowX != -1)
1221     x = editor->nUDArrowX;
1222   else {
1223     if (editor->bCaretAtEnd)
1224     {
1225       pRun = ME_FindItemBack(pRun, diRun);
1226       assert(pRun);
1227       x = pRun->member.run.pt.x + pRun->member.run.nWidth;
1228     }
1229     else {
1230       x = pRun->member.run.pt.x;
1231       x += ME_PointFromChar(editor, &pRun->member.run, pCursor->nOffset, TRUE);
1232     }
1233     editor->nUDArrowX = x;
1234   }
1235   return x;
1236 }
1237
1238
1239 static void
1240 ME_MoveCursorLines(ME_TextEditor *editor, ME_Cursor *pCursor, int nRelOfs)
1241 {
1242   ME_DisplayItem *pRun = pCursor->pRun;
1243   ME_DisplayItem *pOldPara = pCursor->pPara;
1244   ME_DisplayItem *pItem, *pNewPara;
1245   int x = ME_GetXForArrow(editor, pCursor);
1246
1247   if (editor->bCaretAtEnd && !pCursor->nOffset)
1248     if (!ME_PrevRun(&pOldPara, &pRun, TRUE))
1249       return;
1250
1251   if (nRelOfs == -1)
1252   {
1253     /* start of this row */
1254     pItem = ME_FindItemBack(pRun, diStartRow);
1255     assert(pItem);
1256     /* start of the previous row */
1257     pItem = ME_FindItemBack(pItem, diStartRow);
1258     if (!pItem)
1259       return; /* row not found - ignore */
1260     pNewPara = ME_GetParagraph(pItem);
1261     if (pOldPara->member.para.nFlags & MEPF_ROWEND ||
1262         (pOldPara->member.para.pCell &&
1263          pOldPara->member.para.pCell != pNewPara->member.para.pCell))
1264     {
1265       /* Brought out of a cell */
1266       pNewPara = ME_GetTableRowStart(pOldPara)->member.para.prev_para;
1267       if (pNewPara->type == diTextStart)
1268         return; /* At the top, so don't go anywhere. */
1269       pItem = ME_FindItemFwd(pNewPara, diStartRow);
1270     }
1271     if (pNewPara->member.para.nFlags & MEPF_ROWEND)
1272     {
1273       /* Brought into a table row */
1274       ME_Cell *cell = &ME_FindItemBack(pNewPara, diCell)->member.cell;
1275       while (x < cell->pt.x && cell->prev_cell)
1276         cell = &cell->prev_cell->member.cell;
1277       if (cell->next_cell) /* else - we are still at the end of the row */
1278         pItem = ME_FindItemBack(cell->next_cell, diStartRow);
1279     }
1280   }
1281   else
1282   {
1283     /* start of the next row */
1284     pItem = ME_FindItemFwd(pRun, diStartRow);
1285     if (!pItem)
1286       return; /* row not found - ignore */
1287     pNewPara = ME_GetParagraph(pItem);
1288     if (pOldPara->member.para.nFlags & MEPF_ROWSTART ||
1289         (pOldPara->member.para.pCell &&
1290          pOldPara->member.para.pCell != pNewPara->member.para.pCell))
1291     {
1292       /* Brought out of a cell */
1293       pNewPara = ME_GetTableRowEnd(pOldPara)->member.para.next_para;
1294       if (pNewPara->type == diTextEnd)
1295         return; /* At the bottom, so don't go anywhere. */
1296       pItem = ME_FindItemFwd(pNewPara, diStartRow);
1297     }
1298     if (pNewPara->member.para.nFlags & MEPF_ROWSTART)
1299     {
1300       /* Brought into a table row */
1301       ME_DisplayItem *cell = ME_FindItemFwd(pNewPara, diCell);
1302       while (cell->member.cell.next_cell &&
1303              x >= cell->member.cell.next_cell->member.cell.pt.x)
1304         cell = cell->member.cell.next_cell;
1305       pItem = ME_FindItemFwd(cell, diStartRow);
1306     }
1307   }
1308   if (!pItem)
1309   {
1310     /* row not found - ignore */
1311     return;
1312   }
1313   ME_FindRunInRow(editor, pItem, x, pCursor, &editor->bCaretAtEnd);
1314   assert(pCursor->pRun);
1315   assert(pCursor->pRun->type == diRun);
1316 }
1317
1318 static void ME_ArrowPageUp(ME_TextEditor *editor, ME_Cursor *pCursor)
1319 {
1320   ME_DisplayItem *p = ME_FindItemFwd(editor->pBuffer->pFirst, diStartRow);
1321
1322   if (editor->vert_si.nPos < p->member.row.nHeight)
1323   {
1324     ME_SetCursorToStart(editor, pCursor);
1325     editor->bCaretAtEnd = FALSE;
1326     /* Native clears seems to clear this x value on page up at the top
1327      * of the text, but not on page down at the end of the text.
1328      * Doesn't make sense, but we try to be bug for bug compatible. */
1329     editor->nUDArrowX = -1;
1330   } else {
1331     ME_DisplayItem *pRun = pCursor->pRun;
1332     ME_DisplayItem *pLast;
1333     int x, y, yd, yp;
1334     int yOldScrollPos = editor->vert_si.nPos;
1335
1336     x = ME_GetXForArrow(editor, pCursor);
1337     if (!pCursor->nOffset && editor->bCaretAtEnd)
1338       pRun = ME_FindItemBack(pRun, diRun);
1339
1340     p = ME_FindItemBack(pRun, diStartRowOrParagraph);
1341     assert(p->type == diStartRow);
1342     yp = ME_FindItemBack(p, diParagraph)->member.para.pt.y;
1343     y = yp + p->member.row.pt.y;
1344
1345     ME_ScrollUp(editor, editor->sizeWindow.cy);
1346     /* Only move the cursor by the amount scrolled. */
1347     yd = y + editor->vert_si.nPos - yOldScrollPos;
1348     pLast = p;
1349
1350     do {
1351       p = ME_FindItemBack(p, diStartRowOrParagraph);
1352       if (!p)
1353         break;
1354       if (p->type == diParagraph) { /* crossing paragraphs */
1355         if (p->member.para.prev_para == NULL)
1356           break;
1357         yp = p->member.para.prev_para->member.para.pt.y;
1358         continue;
1359       }
1360       y = yp + p->member.row.pt.y;
1361       if (y < yd)
1362         break;
1363       pLast = p;
1364     } while(1);
1365
1366     ME_FindRunInRow(editor, pLast, x, pCursor, &editor->bCaretAtEnd);
1367   }
1368   assert(pCursor->pRun);
1369   assert(pCursor->pRun->type == diRun);
1370 }
1371
1372 static void ME_ArrowPageDown(ME_TextEditor *editor, ME_Cursor *pCursor)
1373 {
1374   ME_DisplayItem *pLast;
1375   int x, y;
1376
1377   /* Find y position of the last row */
1378   pLast = editor->pBuffer->pLast;
1379   y = pLast->member.para.prev_para->member.para.pt.y
1380       + ME_FindItemBack(pLast, diStartRow)->member.row.pt.y;
1381
1382   x = ME_GetXForArrow(editor, pCursor);
1383
1384   if (editor->vert_si.nPos >= y - editor->sizeWindow.cy)
1385   {
1386     ME_SetCursorToEnd(editor, pCursor);
1387     editor->bCaretAtEnd = FALSE;
1388   } else {
1389     ME_DisplayItem *pRun = pCursor->pRun;
1390     ME_DisplayItem *p;
1391     int yd, yp;
1392     int yOldScrollPos = editor->vert_si.nPos;
1393
1394     if (!pCursor->nOffset && editor->bCaretAtEnd)
1395       pRun = ME_FindItemBack(pRun, diRun);
1396
1397     p = ME_FindItemBack(pRun, diStartRowOrParagraph);
1398     assert(p->type == diStartRow);
1399     yp = ME_FindItemBack(p, diParagraph)->member.para.pt.y;
1400     y = yp + p->member.row.pt.y;
1401
1402     /* For native richedit controls:
1403      * v1.0 - v3.1 can only scroll down as far as the scrollbar lets us
1404      * v4.1 can scroll past this position here. */
1405     ME_ScrollDown(editor, editor->sizeWindow.cy);
1406     /* Only move the cursor by the amount scrolled. */
1407     yd = y + editor->vert_si.nPos - yOldScrollPos;
1408     pLast = p;
1409
1410     do {
1411       p = ME_FindItemFwd(p, diStartRowOrParagraph);
1412       if (!p)
1413         break;
1414       if (p->type == diParagraph) {
1415         yp = p->member.para.pt.y;
1416         continue;
1417       }
1418       y = yp + p->member.row.pt.y;
1419       if (y >= yd)
1420         break;
1421       pLast = p;
1422     } while(1);
1423
1424     ME_FindRunInRow(editor, pLast, x, pCursor, &editor->bCaretAtEnd);
1425   }
1426   assert(pCursor->pRun);
1427   assert(pCursor->pRun->type == diRun);
1428 }
1429
1430 static void ME_ArrowHome(ME_TextEditor *editor, ME_Cursor *pCursor)
1431 {
1432   ME_DisplayItem *pRow = ME_FindItemBack(pCursor->pRun, diStartRow);
1433   if (pRow) {
1434     ME_DisplayItem *pRun;
1435     if (editor->bCaretAtEnd && !pCursor->nOffset) {
1436       pRow = ME_FindItemBack(pRow, diStartRow);
1437       if (!pRow)
1438         return;
1439     }
1440     pRun = ME_FindItemFwd(pRow, diRun);
1441     if (pRun) {
1442       pCursor->pRun = pRun;
1443       assert(pCursor->pPara == ME_GetParagraph(pRun));
1444       pCursor->nOffset = 0;
1445     }
1446   }
1447   editor->bCaretAtEnd = FALSE;
1448 }
1449
1450 static void ME_ArrowCtrlHome(ME_TextEditor *editor, ME_Cursor *pCursor)
1451 {
1452   ME_SetCursorToStart(editor, pCursor);
1453   editor->bCaretAtEnd = FALSE;
1454 }
1455
1456 static void ME_ArrowEnd(ME_TextEditor *editor, ME_Cursor *pCursor)
1457 {
1458   ME_DisplayItem *pRow;
1459
1460   if (editor->bCaretAtEnd && !pCursor->nOffset)
1461     return;
1462
1463   pRow = ME_FindItemFwd(pCursor->pRun, diStartRowOrParagraphOrEnd);
1464   assert(pRow);
1465   if (pRow->type == diStartRow) {
1466     ME_DisplayItem *pRun = ME_FindItemFwd(pRow, diRun);
1467     assert(pRun);
1468     pCursor->pRun = pRun;
1469     assert(pCursor->pPara == ME_GetParagraph(pCursor->pRun));
1470     pCursor->nOffset = 0;
1471     editor->bCaretAtEnd = TRUE;
1472     return;
1473   }
1474   pCursor->pRun = ME_FindItemBack(pRow, diRun);
1475   assert(pCursor->pRun && pCursor->pRun->member.run.nFlags & MERF_ENDPARA);
1476   assert(pCursor->pPara == ME_GetParagraph(pCursor->pRun));
1477   pCursor->nOffset = 0;
1478   editor->bCaretAtEnd = FALSE;
1479 }
1480
1481 static void ME_ArrowCtrlEnd(ME_TextEditor *editor, ME_Cursor *pCursor)
1482 {
1483   ME_SetCursorToEnd(editor, pCursor);
1484   editor->bCaretAtEnd = FALSE;
1485 }
1486
1487 BOOL ME_IsSelection(ME_TextEditor *editor)
1488 {
1489   return editor->pCursors[0].pRun != editor->pCursors[1].pRun ||
1490          editor->pCursors[0].nOffset != editor->pCursors[1].nOffset;
1491 }
1492
1493 void ME_DeleteSelection(ME_TextEditor *editor)
1494 {
1495   int from, to;
1496   int nStartCursor = ME_GetSelectionOfs(editor, &from, &to);
1497   int nEndCursor = nStartCursor ^ 1;
1498   ME_DeleteTextAtCursor(editor, nStartCursor, to - from);
1499   editor->pCursors[nEndCursor] = editor->pCursors[nStartCursor];
1500 }
1501
1502 ME_Style *ME_GetSelectionInsertStyle(ME_TextEditor *editor)
1503 {
1504   return ME_GetInsertStyle(editor, 0);
1505 }
1506
1507 void ME_SendSelChange(ME_TextEditor *editor)
1508 {
1509   SELCHANGE sc;
1510
1511   if (!(editor->nEventMask & ENM_SELCHANGE))
1512     return;
1513
1514   sc.nmhdr.hwndFrom = NULL;
1515   sc.nmhdr.idFrom = 0;
1516   sc.nmhdr.code = EN_SELCHANGE;
1517   ME_GetSelectionOfs(editor, &sc.chrg.cpMin, &sc.chrg.cpMax);
1518   sc.seltyp = SEL_EMPTY;
1519   if (sc.chrg.cpMin != sc.chrg.cpMax)
1520     sc.seltyp |= SEL_TEXT;
1521   if (sc.chrg.cpMin < sc.chrg.cpMax+1) /* what were RICHEDIT authors thinking ? */
1522     sc.seltyp |= SEL_MULTICHAR;
1523   TRACE("cpMin=%d cpMax=%d seltyp=%d (%s %s)\n",
1524     sc.chrg.cpMin, sc.chrg.cpMax, sc.seltyp,
1525     (sc.seltyp & SEL_TEXT) ? "SEL_TEXT" : "",
1526     (sc.seltyp & SEL_MULTICHAR) ? "SEL_MULTICHAR" : "");
1527   if (sc.chrg.cpMin != editor->notified_cr.cpMin || sc.chrg.cpMax != editor->notified_cr.cpMax)
1528   {
1529     ME_ClearTempStyle(editor);
1530
1531     editor->notified_cr = sc.chrg;
1532     ITextHost_TxNotify(editor->texthost, sc.nmhdr.code, &sc);
1533   }
1534 }
1535
1536 BOOL
1537 ME_ArrowKey(ME_TextEditor *editor, int nVKey, BOOL extend, BOOL ctrl)
1538 {
1539   int nCursor = 0;
1540   ME_Cursor *p = &editor->pCursors[nCursor];
1541   ME_Cursor tmp_curs = *p;
1542   BOOL success = FALSE;
1543
1544   ME_CheckCharOffsets(editor);
1545   switch(nVKey) {
1546     case VK_LEFT:
1547       editor->bCaretAtEnd = FALSE;
1548       if (ctrl)
1549         success = ME_MoveCursorWords(editor, &tmp_curs, -1);
1550       else
1551         success = ME_MoveCursorChars(editor, &tmp_curs, -1);
1552       break;
1553     case VK_RIGHT:
1554       editor->bCaretAtEnd = FALSE;
1555       if (ctrl)
1556         success = ME_MoveCursorWords(editor, &tmp_curs, +1);
1557       else
1558         success = ME_MoveCursorChars(editor, &tmp_curs, +1);
1559       break;
1560     case VK_UP:
1561       ME_MoveCursorLines(editor, &tmp_curs, -1);
1562       break;
1563     case VK_DOWN:
1564       ME_MoveCursorLines(editor, &tmp_curs, +1);
1565       break;
1566     case VK_PRIOR:
1567       ME_ArrowPageUp(editor, &tmp_curs);
1568       break;
1569     case VK_NEXT:
1570       ME_ArrowPageDown(editor, &tmp_curs);
1571       break;
1572     case VK_HOME: {
1573       if (ctrl)
1574         ME_ArrowCtrlHome(editor, &tmp_curs);
1575       else
1576         ME_ArrowHome(editor, &tmp_curs);
1577       editor->bCaretAtEnd = FALSE;
1578       break;
1579     }
1580     case VK_END:
1581       if (ctrl)
1582         ME_ArrowCtrlEnd(editor, &tmp_curs);
1583       else
1584         ME_ArrowEnd(editor, &tmp_curs);
1585       break;
1586   }
1587
1588   if (!extend)
1589     editor->pCursors[1] = tmp_curs;
1590   *p = tmp_curs;
1591
1592   ME_InvalidateSelection(editor);
1593   ME_Repaint(editor);
1594   ITextHost_TxShowCaret(editor->texthost, FALSE);
1595   ME_EnsureVisible(editor, &tmp_curs);
1596   ME_ShowCaret(editor);
1597   ME_SendSelChange(editor);
1598   return success;
1599 }