dlls/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   if (ME_GetCursorOfs(&editor->pCursors[0]) < ME_GetCursorOfs(&editor->pCursors[1]))
  60   {
  61     *from = &editor->pCursors[0];
  62     *to = &editor->pCursors[1];
  63     return 0;
  64   } else {
  65     *from = &editor->pCursors[1];
  66     *to = &editor->pCursors[0];
  67     return 1;
  68   }
  69 }
  70
  71 int ME_GetTextLength(ME_TextEditor *editor)
  72 {
  73   ME_Cursor cursor;
  74   ME_SetCursorToEnd(editor, &cursor);
  75   return ME_GetCursorOfs(&cursor);
  76 }
  77
  78
  79 int ME_GetTextLengthEx(ME_TextEditor *editor, const GETTEXTLENGTHEX *how)
  80 {
  81   int length;
  82
  83   if (how->flags & GTL_PRECISE && how->flags & GTL_CLOSE)
  84     return E_INVALIDARG;
  85   if (how->flags & GTL_NUMCHARS && how->flags & GTL_NUMBYTES)
  86     return E_INVALIDARG;
  87
  88   length = ME_GetTextLength(editor);
  89
  90   if ((editor->styleFlags & ES_MULTILINE)
  91         && (how->flags & GTL_USECRLF)
  92         && !editor->bEmulateVersion10) /* Ignore GTL_USECRLF flag in 1.0 emulation */
  93     length += editor->nParagraphs - 1;
  94
  95   if (how->flags & GTL_NUMBYTES ||
  96       (how->flags & GTL_PRECISE &&     /* GTL_PRECISE seems to imply GTL_NUMBYTES */
  97        !(how->flags & GTL_NUMCHARS)))  /* unless GTL_NUMCHARS is given */
  98   {
  99     CPINFO cpinfo;
 100
 101     if (how->codepage == 1200)
 102       return length * 2;
 103     if (how->flags & GTL_PRECISE)
 104       FIXME("GTL_PRECISE flag unsupported. Using GTL_CLOSE\n");
 105     if (GetCPInfo(how->codepage, &cpinfo))
 106       return length * cpinfo.MaxCharSize;
 107     ERR("Invalid codepage %u\n", how->codepage);
 108     return E_INVALIDARG;
 109   }
 110   return length;
 111 }
 112
 113
 114 int ME_SetSelection(ME_TextEditor *editor, int from, int to)
 115 {
 116   int selectionEnd = 0;
 117   const int len = ME_GetTextLength(editor);
 118
 119   /* all negative values are effectively the same */
 120   if (from < 0)
 121     from = -1;
 122   if (to < 0)
 123     to = -1;
 124
 125   /* select all */
 126   if (from == 0 && to == -1)
 127   {
 128     ME_SetCursorToStart(editor, &editor->pCursors[1]);
 129     ME_SetCursorToEnd(editor, &editor->pCursors[0]);
 130     ME_InvalidateSelection(editor);
 131     ME_ClearTempStyle(editor);
 132     return len + 1;
 133   }
 134
 135   /* if both values are equal and also out of bound, that means to */
 136   /* put the selection at the end of the text */
 137   if ((from == to) && (to < 0 || to > len))
 138   {
 139     selectionEnd = 1;
 140   }
 141   else
 142   {
 143     /* if from is negative and to is positive then selection is */
 144     /* deselected and caret moved to end of the current selection */
 145     if (from < 0)
 146     {
 147       int start, end;
 148       ME_GetSelectionOfs(editor, &start, &end);
 149       editor->pCursors[1] = editor->pCursors[0];
 150       ME_Repaint(editor);
 151       ME_ClearTempStyle(editor);
 152       return end;
 153     }
 154
 155     /* adjust to if it's a negative value */
 156     if (to < 0)
 157       to = len + 1;
 158
 159     /* flip from and to if they are reversed */
 160     if (from>to)
 161     {
 162       int tmp = from;
 163       from = to;
 164       to = tmp;
 165     }
 166
 167     /* after fiddling with the values, we find from > len && to > len */
 168     if (from > len)
 169       selectionEnd = 1;
 170     /* special case with to too big */
 171     else if (to > len)
 172       to = len + 1;
 173   }
 174
 175   if (selectionEnd)
 176   {
 177     ME_SetCursorToEnd(editor, &editor->pCursors[0]);
 178     editor->pCursors[1] = editor->pCursors[0];
 179     ME_InvalidateSelection(editor);
 180     ME_ClearTempStyle(editor);
 181     return len;
 182   }
 183
 184   ME_CursorFromCharOfs(editor, from, &editor->pCursors[1]);
 185   editor->pCursors[0] = editor->pCursors[1];
 186   ME_MoveCursorChars(editor, &editor->pCursors[0], to - from);
 187   /* Selection is not allowed in the middle of an end paragraph run. */
 188   if (editor->pCursors[1].pRun->member.run.nFlags & MERF_ENDPARA)
 189     editor->pCursors[1].nOffset = 0;
 190   if (editor->pCursors[0].pRun->member.run.nFlags & MERF_ENDPARA)
 191     editor->pCursors[0].nOffset = 0;
 192   return to;
 193 }
 194
 195
 196 static void
 197 ME_GetCursorCoordinates(ME_TextEditor *editor, ME_Cursor *pCursor,
 198                         int *x, int *y, int *height)
 199 {
 200   ME_DisplayItem *row;
 201   ME_DisplayItem *run = pCursor->pRun;
 202   ME_DisplayItem *para = pCursor->pPara;
 203   ME_DisplayItem *pSizeRun = run;
 204   ME_Context c;
 205   SIZE sz = {0, 0};
 206
 207   assert(height && x && y);
 208   assert(~para->member.para.nFlags & MEPF_REWRAP);
 209   assert(run && run->type == diRun);
 210   assert(para && para->type == diParagraph);
 211
 212   row = ME_FindItemBack(run, diStartRowOrParagraph);
 213   assert(row && row->type == diStartRow);
 214
 215   ME_InitContext(&c, editor, ITextHost_TxGetDC(editor->texthost));
 216
 217   if (!pCursor->nOffset)
 218   {
 219     ME_DisplayItem *prev = ME_FindItemBack(run, diRunOrParagraph);
 220     assert(prev);
 221     if (prev->type == diRun)
 222       pSizeRun = prev;
 223   }
 224   if (editor->bCaretAtEnd && !pCursor->nOffset &&
 225       run == ME_FindItemFwd(row, diRun))
 226   {
 227     ME_DisplayItem *tmp = ME_FindItemBack(row, diRunOrParagraph);
 228     assert(tmp);
 229     if (tmp->type == diRun)
 230     {
 231       row = ME_FindItemBack(tmp, diStartRow);
 232       pSizeRun = run = tmp;
 233       assert(run);
 234       assert(run->type == diRun);
 235       sz = ME_GetRunSize(&c, &para->member.para,
 236                          &run->member.run, run->member.run.strText->nLen,
 237                          row->member.row.nLMargin);
 238     }
 239   }
 240   if (pCursor->nOffset) {
 241     sz = ME_GetRunSize(&c, &para->member.para, &run->member.run,
 242                        pCursor->nOffset, row->member.row.nLMargin);
 243   }
 244
 245   *height = pSizeRun->member.run.nAscent + pSizeRun->member.run.nDescent;
 246   *x = c.rcView.left + run->member.run.pt.x + sz.cx - editor->horz_si.nPos;
 247   *y = c.rcView.top + para->member.para.pt.y + row->member.row.nBaseline
 248        + run->member.run.pt.y - pSizeRun->member.run.nAscent
 249        - editor->vert_si.nPos;
 250   ME_DestroyContext(&c);
 251   return;
 252 }
 253
 254
 255 void
 256 ME_MoveCaret(ME_TextEditor *editor)
 257 {
 258   int x, y, height;
 259
 260   ME_GetCursorCoordinates(editor, &editor->pCursors[0], &x, &y, &height);
 261   if(editor->bHaveFocus && !ME_IsSelection(editor))
 262   {
 263     x = min(x, editor->rcFormat.right-1);
 264     ITextHost_TxCreateCaret(editor->texthost, NULL, 0, height);
 265     ITextHost_TxSetCaretPos(editor->texthost, x, y);
 266   }
 267 }
 268
 269
 270 void ME_ShowCaret(ME_TextEditor *ed)
 271 {
 272   ME_MoveCaret(ed);
 273   if(ed->bHaveFocus && !ME_IsSelection(ed))
 274     ITextHost_TxShowCaret(ed->texthost, TRUE);
 275 }
 276
 277 void ME_HideCaret(ME_TextEditor *ed)
 278 {
 279   if(!ed->bHaveFocus || ME_IsSelection(ed))
 280   {
 281     ITextHost_TxShowCaret(ed->texthost, FALSE);
 282     DestroyCaret();
 283   }
 284 }
 285
 286 BOOL ME_InternalDeleteText(ME_TextEditor *editor, ME_Cursor *start,
 287                            int nChars, BOOL bForce)
 288 {
 289   ME_Cursor c = *start;
 290   int nOfs = ME_GetCursorOfs(start);
 291   int shift = 0;
 292   int totalChars = nChars;
 293   ME_DisplayItem *start_para;
 294
 295   /* Prevent deletion past last end of paragraph run. */
 296   nChars = min(nChars, ME_GetTextLength(editor) - nOfs);
 297   start_para = c.pPara;
 298
 299   if (!bForce)
 300   {
 301     ME_ProtectPartialTableDeletion(editor, &c, &nChars);
 302     if (nChars == 0)
 303       return FALSE;
 304   }
 305
 306   while(nChars > 0)
 307   {
 308     ME_Run *run;
 309     ME_CursorFromCharOfs(editor, nOfs+nChars, &c);
 310     if (!c.nOffset &&
 311         nOfs+nChars == (c.pRun->member.run.nCharOfs
 312                         + c.pPara->member.para.nCharOfs))
 313     {
 314       /* We aren't deleting anything in this run, so we will go back to the
 315        * last run we are deleting text in. */
 316       ME_PrevRun(&c.pPara, &c.pRun);
 317       c.nOffset = c.pRun->member.run.strText->nLen;
 318     }
 319     run = &c.pRun->member.run;
 320     if (run->nFlags & MERF_ENDPARA) {
 321       int eollen = c.pRun->member.run.strText->nLen;
 322       BOOL keepFirstParaFormat;
 323
 324       if (!ME_FindItemFwd(c.pRun, diParagraph))
 325       {
 326         return TRUE;
 327       }
 328       keepFirstParaFormat = (totalChars == nChars && nChars <= eollen &&
 329                              run->nCharOfs);
 330       if (!editor->bEmulateVersion10) /* v4.1 */
 331       {
 332         ME_DisplayItem *next_para = ME_FindItemFwd(c.pRun, diParagraphOrEnd);
 333         ME_DisplayItem *this_para = next_para->member.para.prev_para;
 334
 335         /* The end of paragraph before a table row is only deleted if there
 336          * is nothing else on the line before it. */
 337         if (this_para == start_para &&
 338             next_para->member.para.nFlags & MEPF_ROWSTART)
 339         {
 340           /* If the paragraph will be empty, then it should be deleted, however
 341            * it still might have text right now which would inherit the
 342            * MEPF_STARTROW property if we joined it right now.
 343            * Instead we will delete it after the preceding text is deleted. */
 344           if (nOfs > this_para->member.para.nCharOfs) {
 345             /* Skip this end of line. */
 346             nChars -= (eollen < nChars) ? eollen : nChars;
 347             continue;
 348           }
 349           keepFirstParaFormat = TRUE;
 350         }
 351       }
 352       ME_JoinParagraphs(editor, c.pPara, keepFirstParaFormat);
 353       /* ME_SkipAndPropagateCharOffset(p->pRun, shift); */
 354       ME_CheckCharOffsets(editor);
 355       nChars -= (eollen < nChars) ? eollen : nChars;
 356       continue;
 357     }
 358     else
 359     {
 360       ME_Cursor cursor;
 361       int nCharsToDelete = min(nChars, c.nOffset);
 362       int i;
 363
 364       c.nOffset -= nCharsToDelete;
 365
 366       ME_FindItemBack(c.pRun, diParagraph)->member.para.nFlags |= MEPF_REWRAP;
 367
 368       cursor = c;
 369       /* nChars is the number of characters that should be deleted from the
 370          PRECEDING runs (these BEFORE cursor.pRun)
 371          nCharsToDelete is a number of chars to delete from THIS run */
 372       nChars -= nCharsToDelete;
 373       shift -= nCharsToDelete;
 374       TRACE("Deleting %d (remaning %d) chars at %d in '%s' (%d)\n",
 375         nCharsToDelete, nChars, c.nOffset,
 376         debugstr_w(run->strText->szData), run->strText->nLen);
 377
 378       if (!c.nOffset && run->strText->nLen == nCharsToDelete)
 379       {
 380         /* undo = reinsert whole run */
 381         /* nOfs is a character offset (from the start of the document
 382            to the current (deleted) run */
 383         ME_UndoItem *pUndo = ME_AddUndoItem(editor, diUndoInsertRun, c.pRun);
 384         if (pUndo)
 385           pUndo->di.member.run.nCharOfs = nOfs+nChars;
 386       }
 387       else
 388       {
 389         /* undo = reinsert partial run */
 390         ME_UndoItem *pUndo = ME_AddUndoItem(editor, diUndoInsertRun, c.pRun);
 391         if (pUndo) {
 392           ME_DestroyString(pUndo->di.member.run.strText);
 393           pUndo->di.member.run.nCharOfs = nOfs+nChars;
 394           pUndo->di.member.run.strText = ME_MakeStringN(run->strText->szData+c.nOffset, nCharsToDelete);
 395         }
 396       }
 397       TRACE("Post deletion string: %s (%d)\n", debugstr_w(run->strText->szData), run->strText->nLen);
 398       TRACE("Shift value: %d\n", shift);
 399       ME_StrDeleteV(run->strText, c.nOffset, nCharsToDelete);
 400
 401       /* update cursors (including c) */
 402       for (i=-1; i<editor->nCursors; i++) {
 403         ME_Cursor *pThisCur = editor->pCursors + i;
 404         if (i == -1) pThisCur = &c;
 405         if (pThisCur->pRun == cursor.pRun) {
 406           if (pThisCur->nOffset > cursor.nOffset) {
 407             if (pThisCur->nOffset-cursor.nOffset < nCharsToDelete)
 408               pThisCur->nOffset = cursor.nOffset;
 409             else
 410               pThisCur->nOffset -= nCharsToDelete;
 411             assert(pThisCur->nOffset >= 0);
 412             assert(pThisCur->nOffset <= run->strText->nLen);
 413           }
 414           if (pThisCur->nOffset == run->strText->nLen)
 415           {
 416             pThisCur->pRun = ME_FindItemFwd(pThisCur->pRun, diRunOrParagraphOrEnd);
 417             assert(pThisCur->pRun->type == diRun);
 418             pThisCur->nOffset = 0;
 419           }
 420         }
 421       }
 422
 423       /* c = updated data now */
 424
 425       if (c.pRun == cursor.pRun)
 426         ME_SkipAndPropagateCharOffset(c.pRun, shift);
 427       else
 428         ME_PropagateCharOffset(c.pRun, shift);
 429
 430       if (!cursor.pRun->member.run.strText->nLen)
 431       {
 432         TRACE("Removing useless run\n");
 433         ME_Remove(cursor.pRun);
 434         ME_DestroyDisplayItem(cursor.pRun);
 435       }
 436
 437       shift = 0;
 438       /*
 439       ME_CheckCharOffsets(editor);
 440       */
 441       continue;
 442     }
 443   }
 444   return TRUE;
 445 }
 446
 447 BOOL ME_DeleteTextAtCursor(ME_TextEditor *editor, int nCursor, int nChars)
 448 {
 449   assert(nCursor>=0 && nCursor<editor->nCursors);
 450   /* text operations set modified state */
 451   editor->nModifyStep = 1;
 452   return ME_InternalDeleteText(editor, &editor->pCursors[nCursor],
 453                                nChars, FALSE);
 454 }
 455
 456 static ME_DisplayItem *
 457 ME_InternalInsertTextFromCursor(ME_TextEditor *editor, int nCursor,
 458                                 const WCHAR *str, int len, ME_Style *style,
 459                                 int flags)
 460 {
 461   ME_Cursor *p = &editor->pCursors[nCursor];
 462
 463   editor->bCaretAtEnd = FALSE;
 464
 465   assert(p->pRun->type == diRun);
 466
 467   return ME_InsertRunAtCursor(editor, p, style, str, len, flags);
 468 }
 469
 470
 471 void ME_InsertOLEFromCursor(ME_TextEditor *editor, const REOBJECT* reo, int nCursor)
 472 {
 473   ME_Style              *pStyle = ME_GetInsertStyle(editor, nCursor);
 474   ME_DisplayItem        *di;
 475   WCHAR                 space = ' ';
 476
 477   /* FIXME no no no */
 478   if (ME_IsSelection(editor))
 479     ME_DeleteSelection(editor);
 480
 481   di = ME_InternalInsertTextFromCursor(editor, nCursor, &space, 1, pStyle,
 482                                        MERF_GRAPHICS);
 483   di->member.run.ole_obj = ALLOC_OBJ(*reo);
 484   ME_CopyReObject(di->member.run.ole_obj, reo);
 485   ME_ReleaseStyle(pStyle);
 486 }
 487
 488
 489 void ME_InsertEndRowFromCursor(ME_TextEditor *editor, int nCursor)
 490 {
 491   ME_Style              *pStyle = ME_GetInsertStyle(editor, nCursor);
 492   WCHAR                 space = ' ';
 493
 494   /* FIXME no no no */
 495   if (ME_IsSelection(editor))
 496     ME_DeleteSelection(editor);
 497
 498   ME_InternalInsertTextFromCursor(editor, nCursor, &space, 1, pStyle,
 499                                   MERF_ENDROW);
 500   ME_ReleaseStyle(pStyle);
 501 }
 502
 503
 504 void ME_InsertTextFromCursor(ME_TextEditor *editor, int nCursor,
 505   const WCHAR *str, int len, ME_Style *style)
 506 {
 507   const WCHAR *pos;
 508   ME_Cursor *p = NULL;
 509   int oldLen;
 510
 511   /* FIXME really HERE ? */
 512   if (ME_IsSelection(editor))
 513     ME_DeleteSelection(editor);
 514
 515   /* FIXME: is this too slow? */
 516   /* Didn't affect performance for WM_SETTEXT (around 50sec/30K) */
 517   oldLen = ME_GetTextLength(editor);
 518
 519   /* text operations set modified state */
 520   editor->nModifyStep = 1;
 521
 522   assert(style);
 523
 524   assert(nCursor>=0 && nCursor<editor->nCursors);
 525   if (len == -1)
 526     len = lstrlenW(str);
 527
 528   /* grow the text limit to fit our text */
 529   if(editor->nTextLimit < oldLen +len)
 530     editor->nTextLimit = oldLen + len;
 531
 532   pos = str;
 533
 534   while (len)
 535   {
 536     /* FIXME this sucks - no respect for unicode (what else can be a line separator in unicode?) */
 537     while(pos - str < len && *pos != '\r' && *pos != '\n' && *pos != '\t')
 538       pos++;
 539
 540     if (pos != str) { /* handle text */
 541       ME_InternalInsertTextFromCursor(editor, nCursor, str, pos-str, style, 0);
 542     } else if (*pos == '\t') { /* handle tabs */
 543       WCHAR tab = '\t';
 544       ME_InternalInsertTextFromCursor(editor, nCursor, &tab, 1, style, MERF_TAB);
 545       pos++;
 546     } else { /* handle EOLs */
 547       ME_DisplayItem *tp, *end_run;
 548       ME_Style *tmp_style;
 549       int eol_len = 0;
 550
 551       /* Find number of CR and LF in end of paragraph run */
 552       if (*pos =='\r')
 553       {
 554         if (len > 1 && pos[1] == '\n')
 555           eol_len = 2;
 556         else if (len > 2 && pos[1] == '\r' && pos[2] == '\n')
 557           eol_len = 3;
 558         else
 559           eol_len = 1;
 560       } else {
 561         assert(*pos == '\n');
 562         eol_len = 1;
 563       }
 564       pos += eol_len;
 565
 566       if (!editor->bEmulateVersion10 && eol_len == 3)
 567       {
 568         /* handle special \r\r\n sequence (richedit 2.x and higher only) */
 569         WCHAR space = ' ';
 570         ME_InternalInsertTextFromCursor(editor, nCursor, &space, 1, style, 0);
 571       } else {
 572         ME_String *eol_str;
 573
 574         if (!editor->bEmulateVersion10) {
 575           WCHAR cr = '\r';
 576           eol_str = ME_MakeStringN(&cr, 1);
 577         } else {
 578           eol_str = ME_MakeStringN(str, eol_len);
 579         }
 580
 581         p = &editor->pCursors[nCursor];
 582         if (p->nOffset) {
 583           ME_SplitRunSimple(editor, p->pRun, p->nOffset);
 584           p = &editor->pCursors[nCursor];
 585         }
 586         tmp_style = ME_GetInsertStyle(editor, nCursor);
 587         /* ME_SplitParagraph increases style refcount */
 588         tp = ME_SplitParagraph(editor, p->pRun, p->pRun->member.run.style, eol_str, 0);
 589         p->pRun = ME_FindItemFwd(tp, diRun);
 590         p->pPara = tp;
 591         end_run = ME_FindItemBack(tp, diRun);
 592         ME_ReleaseStyle(end_run->member.run.style);
 593         end_run->member.run.style = tmp_style;
 594         p->nOffset = 0;
 595       }
 596     }
 597     len -= pos - str;
 598     str = pos;
 599   }
 600 }
 601
 602 /* Move the cursor nRelOfs characters (either forwards or backwards)
 603  *
 604  * returns the actual number of characters moved.
 605  **/
 606 int ME_MoveCursorChars(ME_TextEditor *editor, ME_Cursor *cursor, int nRelOfs)
 607 {
 608   cursor->nOffset += nRelOfs;
 609   if (cursor->nOffset < 0)
 610   {
 611     cursor->nOffset += cursor->pRun->member.run.nCharOfs;
 612     if (cursor->nOffset >= 0)
 613     {
 614       /* new offset in the same paragraph */
 615       do {
 616         cursor->pRun = ME_FindItemBack(cursor->pRun, diRun);
 617       } while (cursor->nOffset < cursor->pRun->member.run.nCharOfs);
 618       cursor->nOffset -= cursor->pRun->member.run.nCharOfs;
 619       return nRelOfs;
 620     }
 621
 622     cursor->nOffset += cursor->pPara->member.para.nCharOfs;
 623     if (cursor->nOffset <= 0)
 624     {
 625       /* moved to the start of the text */
 626       nRelOfs -= cursor->nOffset;
 627       ME_SetCursorToStart(editor, cursor);
 628       return nRelOfs;
 629     }
 630
 631     /* new offset in a previous paragraph */
 632     do {
 633       cursor->pPara = cursor->pPara->member.para.prev_para;
 634     } while (cursor->nOffset < cursor->pPara->member.para.nCharOfs);
 635     cursor->nOffset -= cursor->pPara->member.para.nCharOfs;
 636
 637     cursor->pRun = ME_FindItemBack(cursor->pPara->member.para.next_para, diRun);
 638     while (cursor->nOffset < cursor->pRun->member.run.nCharOfs) {
 639       cursor->pRun = ME_FindItemBack(cursor->pRun, diRun);
 640     }
 641     cursor->nOffset -= cursor->pRun->member.run.nCharOfs;
 642   } else if (cursor->nOffset >= cursor->pRun->member.run.strText->nLen) {
 643     ME_DisplayItem *next_para;
 644     int new_offset;
 645
 646     new_offset = ME_GetCursorOfs(cursor);
 647     next_para = cursor->pPara->member.para.next_para;
 648     if (new_offset < next_para->member.para.nCharOfs)
 649     {
 650       /* new offset in the same paragraph */
 651       do {
 652         cursor->nOffset -= cursor->pRun->member.run.strText->nLen;
 653         cursor->pRun = ME_FindItemFwd(cursor->pRun, diRun);
 654       } while (cursor->nOffset >= cursor->pRun->member.run.strText->nLen);
 655       return nRelOfs;
 656     }
 657
 658     if (new_offset >= ME_GetTextLength(editor))
 659     {
 660       /* new offset at the end of the text */
 661       ME_SetCursorToEnd(editor, cursor);
 662       nRelOfs -= new_offset - ME_GetTextLength(editor);
 663       return nRelOfs;
 664     }
 665
 666     /* new offset in a following paragraph */
 667     do {
 668       cursor->pPara = next_para;
 669       next_para = next_para->member.para.next_para;
 670     } while (new_offset >= next_para->member.para.nCharOfs);
 671
 672     cursor->nOffset = new_offset - cursor->pPara->member.para.nCharOfs;
 673     cursor->pRun = ME_FindItemFwd(cursor->pPara, diRun);
 674     while (cursor->nOffset >= cursor->pRun->member.run.strText->nLen)
 675     {
 676       cursor->nOffset -= cursor->pRun->member.run.strText->nLen;
 677       cursor->pRun = ME_FindItemFwd(cursor->pRun, diRun);
 678     }
 679   } /* else new offset is in the same run */
 680   return nRelOfs;
 681 }
 682
 683
 684 static BOOL
 685 ME_MoveCursorWords(ME_TextEditor *editor, ME_Cursor *cursor, int nRelOfs)
 686 {
 687   ME_DisplayItem *pRun = cursor->pRun, *pOtherRun;
 688   ME_DisplayItem *pPara = cursor->pPara;
 689   int nOffset = cursor->nOffset;
 690
 691   if (nRelOfs == -1)
 692   {
 693     /* Backward movement */
 694     while (TRUE)
 695     {
 696       nOffset = ME_CallWordBreakProc(editor, pRun->member.run.strText,
 697                                      nOffset, WB_MOVEWORDLEFT);
 698       if (nOffset)
 699         break;
 700       pOtherRun = ME_FindItemBack(pRun, diRunOrParagraph);
 701       if (pOtherRun->type == diRun)
 702       {
 703         if (ME_CallWordBreakProc(editor, pOtherRun->member.run.strText,
 704                                  pOtherRun->member.run.strText->nLen - 1,
 705                                  WB_ISDELIMITER)
 706             && !(pRun->member.run.nFlags & MERF_ENDPARA)
 707             && !(cursor->pRun == pRun && cursor->nOffset == 0)
 708             && !ME_CallWordBreakProc(editor, pRun->member.run.strText, 0,
 709                                      WB_ISDELIMITER))
 710           break;
 711         pRun = pOtherRun;
 712         nOffset = pOtherRun->member.run.strText->nLen;
 713       }
 714       else if (pOtherRun->type == diParagraph)
 715       {
 716         if (cursor->pRun == pRun && cursor->nOffset == 0)
 717         {
 718           pPara = pOtherRun;
 719           /* Skip empty start of table row paragraph */
 720           if (pPara->member.para.prev_para->member.para.nFlags & MEPF_ROWSTART)
 721             pPara = pPara->member.para.prev_para;
 722           /* Paragraph breaks are treated as separate words */
 723           if (pPara->member.para.prev_para->type == diTextStart)
 724             return FALSE;
 725
 726           pRun = ME_FindItemBack(pPara, diRun);
 727           pPara = pPara->member.para.prev_para;
 728         }
 729         break;
 730       }
 731     }
 732   }
 733   else
 734   {
 735     /* Forward movement */
 736     BOOL last_delim = FALSE;
 737
 738     while (TRUE)
 739     {
 740       if (last_delim && !ME_CallWordBreakProc(editor, pRun->member.run.strText,
 741                                               nOffset, WB_ISDELIMITER))
 742         break;
 743       nOffset = ME_CallWordBreakProc(editor, pRun->member.run.strText,
 744                                      nOffset, WB_MOVEWORDRIGHT);
 745       if (nOffset < pRun->member.run.strText->nLen)
 746         break;
 747       pOtherRun = ME_FindItemFwd(pRun, diRunOrParagraphOrEnd);
 748       if (pOtherRun->type == diRun)
 749       {
 750         last_delim = ME_CallWordBreakProc(editor, pRun->member.run.strText,
 751                                           nOffset - 1, WB_ISDELIMITER);
 752         pRun = pOtherRun;
 753         nOffset = 0;
 754       }
 755       else if (pOtherRun->type == diParagraph)
 756       {
 757         if (pOtherRun->member.para.nFlags & MEPF_ROWSTART)
 758             pOtherRun = pOtherRun->member.para.next_para;
 759         if (cursor->pRun == pRun) {
 760           pPara = pOtherRun;
 761           pRun = ME_FindItemFwd(pPara, diRun);
 762         }
 763         nOffset = 0;
 764         break;
 765       }
 766       else /* diTextEnd */
 767       {
 768         if (cursor->pRun == pRun)
 769           return FALSE;
 770         nOffset = 0;
 771         break;
 772       }
 773     }
 774   }
 775   cursor->pPara = pPara;
 776   cursor->pRun = pRun;
 777   cursor->nOffset = nOffset;
 778   return TRUE;
 779 }
 780
 781
 782 static void
 783 ME_SelectByType(ME_TextEditor *editor, ME_SelectionType selectionType)
 784 {
 785   /* pCursor[0] is the end of the selection
 786    * pCursor[1] is the start of the selection (or the position selection anchor)
 787    * pCursor[2] and [3] are the selection anchors that are backed up
 788    * so they are kept when the selection changes for drag selection.
 789    */
 790
 791   editor->nSelectionType = selectionType;
 792   switch(selectionType)
 793   {
 794     case stPosition:
 795       break;
 796     case stWord:
 797       ME_MoveCursorWords(editor, &editor->pCursors[0], +1);
 798       editor->pCursors[1] = editor->pCursors[0];
 799       ME_MoveCursorWords(editor, &editor->pCursors[1], -1);
 800       break;
 801     case stLine:
 802     case stParagraph:
 803     {
 804       ME_DisplayItem *pItem;
 805       ME_DIType fwdSearchType, backSearchType;
 806       if (selectionType == stParagraph) {
 807           backSearchType = diParagraph;
 808           fwdSearchType = diParagraphOrEnd;
 809       } else {
 810           backSearchType = diStartRow;
 811           fwdSearchType = diStartRowOrParagraphOrEnd;
 812       }
 813       pItem = ME_FindItemFwd(editor->pCursors[0].pRun, fwdSearchType);
 814       assert(pItem);
 815       if (pItem->type == diTextEnd)
 816           editor->pCursors[0].pRun = ME_FindItemBack(pItem, diRun);
 817       else
 818           editor->pCursors[0].pRun = ME_FindItemFwd(pItem, diRun);
 819       editor->pCursors[0].pPara = ME_GetParagraph(editor->pCursors[0].pRun);
 820       editor->pCursors[0].nOffset = 0;
 821
 822       pItem = ME_FindItemBack(pItem, backSearchType);
 823       editor->pCursors[1].pRun = ME_FindItemFwd(pItem, diRun);
 824       editor->pCursors[1].pPara = ME_GetParagraph(editor->pCursors[1].pRun);
 825       editor->pCursors[1].nOffset = 0;
 826       break;
 827     }
 828     case stDocument:
 829       /* Select everything with cursor anchored from the start of the text */
 830       editor->nSelectionType = stDocument;
 831       ME_SetCursorToStart(editor, &editor->pCursors[1]);
 832       ME_SetCursorToEnd(editor, &editor->pCursors[0]);
 833       break;
 834     default: assert(0);
 835   }
 836   /* Store the anchor positions for extending the selection. */
 837   editor->pCursors[2] = editor->pCursors[0];
 838   editor->pCursors[3] = editor->pCursors[1];
 839 }
 840
 841 int ME_GetCursorOfs(const ME_Cursor *cursor)
 842 {
 843   return cursor->pPara->member.para.nCharOfs
 844          + cursor->pRun->member.run.nCharOfs + cursor->nOffset;
 845 }
 846
 847 /* Helper function for ME_FindPixelPos to find paragraph within tables */
 848 static ME_DisplayItem* ME_FindPixelPosInTableRow(int x, int y,
 849                                                  ME_DisplayItem *para)
 850 {
 851   ME_DisplayItem *cell, *next_cell;
 852   assert(para->member.para.nFlags & MEPF_ROWSTART);
 853   cell = para->member.para.next_para->member.para.pCell;
 854   assert(cell);
 855
 856   /* find the cell we are in */
 857   while ((next_cell = cell->member.cell.next_cell) != NULL) {
 858     if (x < next_cell->member.cell.pt.x)
 859     {
 860       para = ME_FindItemFwd(cell, diParagraph);
 861       /* Found the cell, but there might be multiple paragraphs in
 862        * the cell, so need to search down the cell for the paragraph. */
 863       while (cell == para->member.para.pCell) {
 864         if (y < para->member.para.pt.y + para->member.para.nHeight)
 865         {
 866           if (para->member.para.nFlags & MEPF_ROWSTART)
 867             return ME_FindPixelPosInTableRow(x, y, para);
 868           else
 869             return para;
 870         }
 871         para = para->member.para.next_para;
 872       }
 873       /* Past the end of the cell, so go back to the last cell paragraph */
 874       return para->member.para.prev_para;
 875     }
 876     cell = next_cell;
 877   }
 878   /* Return table row delimiter */
 879   para = ME_FindItemFwd(cell, diParagraph);
 880   assert(para->member.para.nFlags & MEPF_ROWEND);
 881   assert(para->member.para.pFmt->dwMask & PFM_TABLEROWDELIMITER);
 882   assert(para->member.para.pFmt->wEffects & PFE_TABLEROWDELIMITER);
 883   return para;
 884 }
 885
 886 static BOOL ME_ReturnFoundPos(ME_TextEditor *editor, ME_DisplayItem *found,
 887                                ME_Cursor *result, int rx, BOOL isExact)
 888 {
 889   assert(found);
 890   assert(found->type == diRun);
 891   if ((found->member.run.nFlags & MERF_ENDPARA) || rx < 0)
 892     rx = 0;
 893   result->pRun = found;
 894   result->nOffset = ME_CharFromPointCursor(editor, rx, &found->member.run);
 895   if (result->nOffset == found->member.run.strText->nLen && rx)
 896   {
 897     result->pRun = ME_FindItemFwd(result->pRun, diRun);
 898     result->nOffset = 0;
 899   }
 900   result->pPara = ME_GetParagraph(result->pRun);
 901   return isExact;
 902 }
 903
 904 /* Finds the run and offset from the pixel position.
 905  *
 906  * x & y are pixel positions in virtual coordinates into the rich edit control,
 907  * so client coordinates must first be adjusted by the scroll position.
 908  *
 909  * returns TRUE if the result was exactly under the cursor, otherwise returns
 910  * FALSE, and result is set to the closest position to the coordinates.
 911  */
 912 static BOOL ME_FindPixelPos(ME_TextEditor *editor, int x, int y,
 913                             ME_Cursor *result, BOOL *is_eol)
 914 {
 915   ME_DisplayItem *p = editor->pBuffer->pFirst->member.para.next_para;
 916   ME_DisplayItem *last = NULL;
 917   int rx = 0;
 918   BOOL isExact = TRUE;
 919
 920   x -= editor->rcFormat.left;
 921   y -= editor->rcFormat.top;
 922
 923   if (is_eol)
 924     *is_eol = 0;
 925
 926   /* find paragraph */
 927   for (; p != editor->pBuffer->pLast; p = p->member.para.next_para)
 928   {
 929     assert(p->type == diParagraph);
 930     if (y < p->member.para.pt.y + p->member.para.nHeight)
 931     {
 932       if (p->member.para.nFlags & MEPF_ROWSTART)
 933         p = ME_FindPixelPosInTableRow(x, y, p);
 934       y -= p->member.para.pt.y;
 935       p = ME_FindItemFwd(p, diStartRow);
 936       break;
 937     } else if (p->member.para.nFlags & MEPF_ROWSTART) {
 938       p = ME_GetTableRowEnd(p);
 939     }
 940   }
 941   /* find row */
 942   for (; p != editor->pBuffer->pLast; )
 943   {
 944     ME_DisplayItem *pp;
 945     assert(p->type == diStartRow);
 946     if (y < p->member.row.pt.y + p->member.row.nHeight)
 947     {
 948         p = ME_FindItemFwd(p, diRun);
 949         break;
 950     }
 951     pp = ME_FindItemFwd(p, diStartRowOrParagraphOrEnd);
 952     if (pp->type != diStartRow)
 953     {
 954         p = ME_FindItemFwd(p, diRun);
 955         break;
 956     }
 957     p = pp;
 958   }
 959   if (p == editor->pBuffer->pLast)
 960   {
 961     /* The position is below the last paragraph, so the last row will be used
 962      * rather than the end of the text, so the x position will be used to
 963      * determine the offset closest to the pixel position. */
 964     isExact = FALSE;
 965     p = ME_FindItemBack(p, diStartRow);
 966     if (p != NULL){
 967       p = ME_FindItemFwd(p, diRun);
 968     }
 969     else
 970     {
 971       p = editor->pBuffer->pLast;
 972     }
 973   }
 974   for (; p != editor->pBuffer->pLast; p = p->next)
 975   {
 976     switch (p->type)
 977     {
 978     case diRun:
 979       rx = x - p->member.run.pt.x;
 980       if (rx < p->member.run.nWidth)
 981         return ME_ReturnFoundPos(editor, p, result, rx, isExact);
 982       break;
 983     case diStartRow:
 984       isExact = FALSE;
 985       p = ME_FindItemFwd(p, diRun);
 986       if (is_eol) *is_eol = 1;
 987       rx = 0; /* FIXME not sure */
 988       return ME_ReturnFoundPos(editor, p, result, rx, isExact);
 989     case diCell:
 990     case diParagraph:
 991     case diTextEnd:
 992       isExact = FALSE;
 993       rx = 0; /* FIXME not sure */
 994       p = last;
 995       return ME_ReturnFoundPos(editor, p, result, rx, isExact);
 996     default: assert(0);
 997     }
 998     last = p;
 999   }
1000   result->pRun = ME_FindItemBack(p, diRun);
1001   result->pPara = ME_GetParagraph(result->pRun);
1002   result->nOffset = 0;
1003   assert(result->pRun->member.run.nFlags & MERF_ENDPARA);
1004   return FALSE;
1005 }
1006
1007
1008 /* Sets the cursor to the position closest to the pixel position
1009  *
1010  * x & y are pixel positions in client coordinates.
1011  *
1012  * isExact will be set to TRUE if the run is directly under the pixel
1013  * position, FALSE if it not, unless isExact is set to NULL.
1014  *
1015  * return FALSE if outside client area and the cursor is not set,
1016  * otherwise TRUE is returned.
1017  */
1018 BOOL ME_CharFromPos(ME_TextEditor *editor, int x, int y,
1019                     ME_Cursor *cursor, BOOL *isExact)
1020 {
1021   RECT rc;
1022   BOOL bResult;
1023
1024   ITextHost_TxGetClientRect(editor->texthost, &rc);
1025   if (x < 0 || y < 0 || x >= rc.right || y >= rc.bottom) {
1026     if (isExact) *isExact = FALSE;
1027     return FALSE;
1028   }
1029   x += editor->horz_si.nPos;
1030   y += editor->vert_si.nPos;
1031   bResult = ME_FindPixelPos(editor, x, y, cursor, NULL);
1032   if (isExact) *isExact = bResult;
1033   return TRUE;
1034 }
1035
1036
1037
1038 /* Extends the selection with a word, line, or paragraph selection type.
1039  *
1040  * The selection is anchored by editor->pCursors[2-3] such that the text
1041  * between the anchors will remain selected, and one end will be extended.
1042  *
1043  * editor->pCursors[0] should have the position to extend the selection to
1044  * before this function is called.
1045  *
1046  * Nothing will be done if editor->nSelectionType equals stPosition.
1047  */
1048 static void ME_ExtendAnchorSelection(ME_TextEditor *editor)
1049 {
1050   ME_Cursor tmp_cursor;
1051   int curOfs, anchorStartOfs, anchorEndOfs;
1052   if (editor->nSelectionType == stPosition || editor->nSelectionType == stDocument)
1053       return;
1054   curOfs = ME_GetCursorOfs(&editor->pCursors[0]);
1055   anchorStartOfs = ME_GetCursorOfs(&editor->pCursors[3]);
1056   anchorEndOfs = ME_GetCursorOfs(&editor->pCursors[2]);
1057
1058   tmp_cursor = editor->pCursors[0];
1059   editor->pCursors[0] = editor->pCursors[2];
1060   editor->pCursors[1] = editor->pCursors[3];
1061   if (curOfs < anchorStartOfs)
1062   {
1063       /* Extend the left side of selection */
1064       editor->pCursors[1] = tmp_cursor;
1065       if (editor->nSelectionType == stWord)
1066           ME_MoveCursorWords(editor, &editor->pCursors[1], -1);
1067       else
1068       {
1069           ME_DisplayItem *pItem;
1070           ME_DIType searchType = ((editor->nSelectionType == stLine) ?
1071                                   diStartRowOrParagraph:diParagraph);
1072           pItem = ME_FindItemBack(editor->pCursors[1].pRun, searchType);
1073           editor->pCursors[1].pRun = ME_FindItemFwd(pItem, diRun);
1074           editor->pCursors[1].pPara = ME_GetParagraph(editor->pCursors[1].pRun);
1075           editor->pCursors[1].nOffset = 0;
1076       }
1077   }
1078   else if (curOfs >= anchorEndOfs)
1079   {
1080       /* Extend the right side of selection */
1081       editor->pCursors[0] = tmp_cursor;
1082       if (editor->nSelectionType == stWord)
1083           ME_MoveCursorWords(editor, &editor->pCursors[0], +1);
1084       else
1085       {
1086           ME_DisplayItem *pItem;
1087           ME_DIType searchType = ((editor->nSelectionType == stLine) ?
1088                                   diStartRowOrParagraphOrEnd:diParagraphOrEnd);
1089           pItem = ME_FindItemFwd(editor->pCursors[0].pRun, searchType);
1090           if (pItem->type == diTextEnd)
1091               editor->pCursors[0].pRun = ME_FindItemBack(pItem, diRun);
1092           else
1093               editor->pCursors[0].pRun = ME_FindItemFwd(pItem, diRun);
1094           editor->pCursors[0].pPara = ME_GetParagraph(editor->pCursors[0].pRun);
1095           editor->pCursors[0].nOffset = 0;
1096       }
1097   }
1098 }
1099
1100 void ME_LButtonDown(ME_TextEditor *editor, int x, int y, int clickNum)
1101 {
1102   ME_Cursor tmp_cursor;
1103   int is_selection = 0;
1104   BOOL is_shift;
1105
1106   editor->nUDArrowX = -1;
1107
1108   x += editor->horz_si.nPos;
1109   y += editor->vert_si.nPos;
1110
1111   tmp_cursor = editor->pCursors[0];
1112   is_selection = ME_IsSelection(editor);
1113   is_shift = GetKeyState(VK_SHIFT) < 0;
1114
1115   ME_FindPixelPos(editor, x, y, &editor->pCursors[0], &editor->bCaretAtEnd);
1116
1117   if (x >= editor->rcFormat.left || is_shift)
1118   {
1119     if (clickNum > 1)
1120     {
1121       editor->pCursors[1] = editor->pCursors[0];
1122       if (is_shift) {
1123           if (x >= editor->rcFormat.left)
1124               ME_SelectByType(editor, stWord);
1125           else
1126               ME_SelectByType(editor, stParagraph);
1127       } else if (clickNum % 2 == 0) {
1128           ME_SelectByType(editor, stWord);
1129       } else {
1130           ME_SelectByType(editor, stParagraph);
1131       }
1132     }
1133     else if (!is_shift)
1134     {
1135       editor->nSelectionType = stPosition;
1136       editor->pCursors[1] = editor->pCursors[0];
1137     }
1138     else if (!is_selection)
1139     {
1140       editor->nSelectionType = stPosition;
1141       editor->pCursors[1] = tmp_cursor;
1142     }
1143     else if (editor->nSelectionType != stPosition)
1144     {
1145       ME_ExtendAnchorSelection(editor);
1146     }
1147   }
1148   else
1149   {
1150     if (clickNum < 2) {
1151         ME_SelectByType(editor, stLine);
1152     } else if (clickNum % 2 == 0 || is_shift) {
1153         ME_SelectByType(editor, stParagraph);
1154     } else {
1155         ME_SelectByType(editor, stDocument);
1156     }
1157   }
1158   ME_InvalidateSelection(editor);
1159   ITextHost_TxShowCaret(editor->texthost, FALSE);
1160   ME_ShowCaret(editor);
1161   ME_ClearTempStyle(editor);
1162   ME_SendSelChange(editor);
1163 }
1164
1165 void ME_MouseMove(ME_TextEditor *editor, int x, int y)
1166 {
1167   ME_Cursor tmp_cursor;
1168
1169   if (editor->nSelectionType == stDocument)
1170       return;
1171   x += editor->horz_si.nPos;
1172   y += editor->vert_si.nPos;
1173
1174   tmp_cursor = editor->pCursors[0];
1175   /* FIXME: do something with the return value of ME_FindPixelPos */
1176   ME_FindPixelPos(editor, x, y, &tmp_cursor, &editor->bCaretAtEnd);
1177
1178   ME_InvalidateSelection(editor);
1179   editor->pCursors[0] = tmp_cursor;
1180   ME_ExtendAnchorSelection(editor);
1181
1182   if (editor->nSelectionType != stPosition &&
1183       memcmp(&editor->pCursors[1], &editor->pCursors[3], sizeof(ME_Cursor)))
1184   {
1185       /* The scroll the cursor towards the other end, since it was the one
1186        * extended by ME_ExtendAnchorSelection */
1187       ME_EnsureVisible(editor, &editor->pCursors[1]);
1188   } else {
1189       ME_EnsureVisible(editor, &editor->pCursors[0]);
1190   }
1191
1192   ME_InvalidateSelection(editor);
1193   ITextHost_TxShowCaret(editor->texthost, FALSE);
1194   ME_ShowCaret(editor);
1195   ME_SendSelChange(editor);
1196 }
1197
1198 static ME_DisplayItem *ME_FindRunInRow(ME_TextEditor *editor, ME_DisplayItem *pRow,
1199                                 int x, int *pOffset, int *pbCaretAtEnd)
1200 {
1201   ME_DisplayItem *pNext, *pLastRun;
1202   pNext = ME_FindItemFwd(pRow, diRunOrStartRow);
1203   assert(pNext->type == diRun);
1204   pLastRun = pNext;
1205   if (pbCaretAtEnd) *pbCaretAtEnd = FALSE;
1206   if (pOffset) *pOffset = 0;
1207   do {
1208     int run_x = pNext->member.run.pt.x;
1209     int width = pNext->member.run.nWidth;
1210     if (x < run_x)
1211     {
1212       return pNext;
1213     }
1214     if (x >= run_x && x < run_x+width)
1215     {
1216       int ch = ME_CharFromPointCursor(editor, x-run_x, &pNext->member.run);
1217       ME_String *s = pNext->member.run.strText;
1218       if (ch < s->nLen) {
1219         if (pOffset)
1220           *pOffset = ch;
1221         return pNext;
1222       }
1223     }
1224     pLastRun = pNext;
1225     pNext = ME_FindItemFwd(pNext, diRunOrStartRow);
1226   } while(pNext && pNext->type == diRun);
1227
1228   if ((pLastRun->member.run.nFlags & MERF_ENDPARA) == 0)
1229   {
1230     pNext = ME_FindItemFwd(pNext, diRun);
1231     if (pbCaretAtEnd) *pbCaretAtEnd = TRUE;
1232     return pNext;
1233   } else {
1234     return pLastRun;
1235   }
1236 }
1237
1238 static int ME_GetXForArrow(ME_TextEditor *editor, ME_Cursor *pCursor)
1239 {
1240   ME_DisplayItem *pRun = pCursor->pRun;
1241   int x;
1242
1243   if (editor->nUDArrowX != -1)
1244     x = editor->nUDArrowX;
1245   else {
1246     if (editor->bCaretAtEnd)
1247     {
1248       pRun = ME_FindItemBack(pRun, diRun);
1249       assert(pRun);
1250       x = pRun->member.run.pt.x + pRun->member.run.nWidth;
1251     }
1252     else {
1253       x = pRun->member.run.pt.x;
1254       x += ME_PointFromChar(editor, &pRun->member.run, pCursor->nOffset);
1255     }
1256     editor->nUDArrowX = x;
1257   }
1258   return x;
1259 }
1260
1261
1262 static void
1263 ME_MoveCursorLines(ME_TextEditor *editor, ME_Cursor *pCursor, int nRelOfs)
1264 {
1265   ME_DisplayItem *pRun = pCursor->pRun;
1266   ME_DisplayItem *pOldPara = pCursor->pPara;
1267   ME_DisplayItem *pItem, *pNewPara;
1268   int x = ME_GetXForArrow(editor, pCursor);
1269
1270   if (editor->bCaretAtEnd && !pCursor->nOffset)
1271     if (!ME_PrevRun(&pOldPara, &pRun))
1272       return;
1273
1274   if (nRelOfs == -1)
1275   {
1276     /* start of this row */
1277     pItem = ME_FindItemBack(pRun, diStartRow);
1278     assert(pItem);
1279     /* start of the previous row */
1280     pItem = ME_FindItemBack(pItem, diStartRow);
1281     if (!pItem)
1282       return; /* row not found - ignore */
1283     pNewPara = ME_GetParagraph(pItem);
1284     if (pOldPara->member.para.nFlags & MEPF_ROWEND ||
1285         (pOldPara->member.para.pCell &&
1286          pOldPara->member.para.pCell != pNewPara->member.para.pCell))
1287     {
1288       /* Brought out of a cell */
1289       pNewPara = ME_GetTableRowStart(pOldPara)->member.para.prev_para;
1290       if (pNewPara->type == diTextStart)
1291         return; /* At the top, so don't go anywhere. */
1292       pItem = ME_FindItemFwd(pNewPara, diStartRow);
1293     }
1294     if (pNewPara->member.para.nFlags & MEPF_ROWEND)
1295     {
1296       /* Brought into a table row */
1297       ME_Cell *cell = &ME_FindItemBack(pNewPara, diCell)->member.cell;
1298       while (x < cell->pt.x && cell->prev_cell)
1299         cell = &cell->prev_cell->member.cell;
1300       if (cell->next_cell) /* else - we are still at the end of the row */
1301         pItem = ME_FindItemBack(cell->next_cell, diStartRow);
1302     }
1303   }
1304   else
1305   {
1306     /* start of the next row */
1307     pItem = ME_FindItemFwd(pRun, diStartRow);
1308     if (!pItem)
1309       return; /* row not found - ignore */
1310     pNewPara = ME_GetParagraph(pItem);
1311     if (pOldPara->member.para.nFlags & MEPF_ROWSTART ||
1312         (pOldPara->member.para.pCell &&
1313          pOldPara->member.para.pCell != pNewPara->member.para.pCell))
1314     {
1315       /* Brought out of a cell */
1316       pNewPara = ME_GetTableRowEnd(pOldPara)->member.para.next_para;
1317       if (pNewPara->type == diTextEnd)
1318         return; /* At the bottom, so don't go anywhere. */
1319       pItem = ME_FindItemFwd(pNewPara, diStartRow);
1320     }
1321     if (pNewPara->member.para.nFlags & MEPF_ROWSTART)
1322     {
1323       /* Brought into a table row */
1324       ME_DisplayItem *cell = ME_FindItemFwd(pNewPara, diCell);
1325       while (cell->member.cell.next_cell &&
1326              x >= cell->member.cell.next_cell->member.cell.pt.x)
1327         cell = cell->member.cell.next_cell;
1328       pItem = ME_FindItemFwd(cell, diStartRow);
1329     }
1330   }
1331   if (!pItem)
1332   {
1333     /* row not found - ignore */
1334     return;
1335   }
1336   pCursor->pRun = ME_FindRunInRow(editor, pItem, x, &pCursor->nOffset, &editor->bCaretAtEnd);
1337   pCursor->pPara = ME_GetParagraph(pCursor->pRun);
1338   assert(pCursor->pRun);
1339   assert(pCursor->pRun->type == diRun);
1340 }
1341
1342 static void ME_ArrowPageUp(ME_TextEditor *editor, ME_Cursor *pCursor)
1343 {
1344   ME_DisplayItem *p = ME_FindItemFwd(editor->pBuffer->pFirst, diStartRow);
1345
1346   if (editor->vert_si.nPos < p->member.row.nHeight)
1347   {
1348     ME_SetCursorToStart(editor, pCursor);
1349     editor->bCaretAtEnd = FALSE;
1350     /* Native clears seems to clear this x value on page up at the top
1351      * of the text, but not on page down at the end of the text.
1352      * Doesn't make sense, but we try to be bug for bug compatible. */
1353     editor->nUDArrowX = -1;
1354   } else {
1355     ME_DisplayItem *pRun = pCursor->pRun;
1356     ME_DisplayItem *pLast;
1357     int x, y, yd, yp;
1358     int yOldScrollPos = editor->vert_si.nPos;
1359
1360     x = ME_GetXForArrow(editor, pCursor);
1361     if (!pCursor->nOffset && editor->bCaretAtEnd)
1362       pRun = ME_FindItemBack(pRun, diRun);
1363
1364     p = ME_FindItemBack(pRun, diStartRowOrParagraph);
1365     assert(p->type == diStartRow);
1366     yp = ME_FindItemBack(p, diParagraph)->member.para.pt.y;
1367     y = yp + p->member.row.pt.y;
1368
1369     ME_ScrollUp(editor, editor->sizeWindow.cy);
1370     /* Only move the cursor by the amount scrolled. */
1371     yd = y + editor->vert_si.nPos - yOldScrollPos;
1372     pLast = p;
1373
1374     do {
1375       p = ME_FindItemBack(p, diStartRowOrParagraph);
1376       if (!p)
1377         break;
1378       if (p->type == diParagraph) { /* crossing paragraphs */
1379         if (p->member.para.prev_para == NULL)
1380           break;
1381         yp = p->member.para.prev_para->member.para.pt.y;
1382         continue;
1383       }
1384       y = yp + p->member.row.pt.y;
1385       if (y < yd)
1386         break;
1387       pLast = p;
1388     } while(1);
1389
1390     pCursor->pRun = ME_FindRunInRow(editor, pLast, x, &pCursor->nOffset,
1391                                     &editor->bCaretAtEnd);
1392     pCursor->pPara = ME_GetParagraph(pCursor->pRun);
1393   }
1394   assert(pCursor->pRun);
1395   assert(pCursor->pRun->type == diRun);
1396 }
1397
1398 static void ME_ArrowPageDown(ME_TextEditor *editor, ME_Cursor *pCursor)
1399 {
1400   ME_DisplayItem *pLast;
1401   int x, y;
1402
1403   /* Find y position of the last row */
1404   pLast = editor->pBuffer->pLast;
1405   y = pLast->member.para.prev_para->member.para.pt.y
1406       + ME_FindItemBack(pLast, diStartRow)->member.row.pt.y;
1407
1408   x = ME_GetXForArrow(editor, pCursor);
1409
1410   if (editor->vert_si.nPos >= y - editor->sizeWindow.cy)
1411   {
1412     ME_SetCursorToEnd(editor, pCursor);
1413     editor->bCaretAtEnd = FALSE;
1414   } else {
1415     ME_DisplayItem *pRun = pCursor->pRun;
1416     ME_DisplayItem *p;
1417     int yd, yp;
1418     int yOldScrollPos = editor->vert_si.nPos;
1419
1420     if (!pCursor->nOffset && editor->bCaretAtEnd)
1421       pRun = ME_FindItemBack(pRun, diRun);
1422
1423     p = ME_FindItemBack(pRun, diStartRowOrParagraph);
1424     assert(p->type == diStartRow);
1425     yp = ME_FindItemBack(p, diParagraph)->member.para.pt.y;
1426     y = yp + p->member.row.pt.y;
1427
1428     /* For native richedit controls:
1429      * v1.0 - v3.1 can only scroll down as far as the scrollbar lets us
1430      * v4.1 can scroll past this position here. */
1431     ME_ScrollDown(editor, editor->sizeWindow.cy);
1432     /* Only move the cursor by the amount scrolled. */
1433     yd = y + editor->vert_si.nPos - yOldScrollPos;
1434     pLast = p;
1435
1436     do {
1437       p = ME_FindItemFwd(p, diStartRowOrParagraph);
1438       if (!p)
1439         break;
1440       if (p->type == diParagraph) {
1441         yp = p->member.para.pt.y;
1442         continue;
1443       }
1444       y = yp + p->member.row.pt.y;
1445       if (y >= yd)
1446         break;
1447       pLast = p;
1448     } while(1);
1449
1450     pCursor->pRun = ME_FindRunInRow(editor, pLast, x, &pCursor->nOffset,
1451                                     &editor->bCaretAtEnd);
1452     pCursor->pPara = ME_GetParagraph(pCursor->pRun);
1453   }
1454   assert(pCursor->pRun);
1455   assert(pCursor->pRun->type == diRun);
1456 }
1457
1458 static void ME_ArrowHome(ME_TextEditor *editor, ME_Cursor *pCursor)
1459 {
1460   ME_DisplayItem *pRow = ME_FindItemBack(pCursor->pRun, diStartRow);
1461   if (pRow) {
1462     ME_DisplayItem *pRun;
1463     if (editor->bCaretAtEnd && !pCursor->nOffset) {
1464       pRow = ME_FindItemBack(pRow, diStartRow);
1465       if (!pRow)
1466         return;
1467     }
1468     pRun = ME_FindItemFwd(pRow, diRun);
1469     if (pRun) {
1470       pCursor->pRun = pRun;
1471       assert(pCursor->pPara == ME_GetParagraph(pRun));
1472       pCursor->nOffset = 0;
1473     }
1474   }
1475   editor->bCaretAtEnd = FALSE;
1476 }
1477
1478 static void ME_ArrowCtrlHome(ME_TextEditor *editor, ME_Cursor *pCursor)
1479 {
1480   ME_SetCursorToStart(editor, pCursor);
1481   editor->bCaretAtEnd = FALSE;
1482 }
1483
1484 static void ME_ArrowEnd(ME_TextEditor *editor, ME_Cursor *pCursor)
1485 {
1486   ME_DisplayItem *pRow;
1487
1488   if (editor->bCaretAtEnd && !pCursor->nOffset)
1489     return;
1490
1491   pRow = ME_FindItemFwd(pCursor->pRun, diStartRowOrParagraphOrEnd);
1492   assert(pRow);
1493   if (pRow->type == diStartRow) {
1494     ME_DisplayItem *pRun = ME_FindItemFwd(pRow, diRun);
1495     assert(pRun);
1496     pCursor->pRun = pRun;
1497     assert(pCursor->pPara == ME_GetParagraph(pCursor->pRun));
1498     pCursor->nOffset = 0;
1499     editor->bCaretAtEnd = TRUE;
1500     return;
1501   }
1502   pCursor->pRun = ME_FindItemBack(pRow, diRun);
1503   assert(pCursor->pRun && pCursor->pRun->member.run.nFlags & MERF_ENDPARA);
1504   assert(pCursor->pPara == ME_GetParagraph(pCursor->pRun));
1505   pCursor->nOffset = 0;
1506   editor->bCaretAtEnd = FALSE;
1507 }
1508
1509 static void ME_ArrowCtrlEnd(ME_TextEditor *editor, ME_Cursor *pCursor)
1510 {
1511   ME_SetCursorToEnd(editor, pCursor);
1512   editor->bCaretAtEnd = FALSE;
1513 }
1514
1515 BOOL ME_IsSelection(ME_TextEditor *editor)
1516 {
1517   return editor->pCursors[0].pRun != editor->pCursors[1].pRun ||
1518          editor->pCursors[0].nOffset != editor->pCursors[1].nOffset;
1519 }
1520
1521 void ME_DeleteSelection(ME_TextEditor *editor)
1522 {
1523   int from, to;
1524   int nStartCursor = ME_GetSelectionOfs(editor, &from, &to);
1525   ME_DeleteTextAtCursor(editor, nStartCursor, to - from);
1526 }
1527
1528 ME_Style *ME_GetSelectionInsertStyle(ME_TextEditor *editor)
1529 {
1530   return ME_GetInsertStyle(editor, 0);
1531 }
1532
1533 void ME_SendSelChange(ME_TextEditor *editor)
1534 {
1535   SELCHANGE sc;
1536
1537   if (!(editor->nEventMask & ENM_SELCHANGE))
1538     return;
1539
1540   sc.nmhdr.hwndFrom = NULL;
1541   sc.nmhdr.idFrom = 0;
1542   sc.nmhdr.code = EN_SELCHANGE;
1543   ME_GetSelectionOfs(editor, &sc.chrg.cpMin, &sc.chrg.cpMax);
1544   sc.seltyp = SEL_EMPTY;
1545   if (sc.chrg.cpMin != sc.chrg.cpMax)
1546     sc.seltyp |= SEL_TEXT;
1547   if (sc.chrg.cpMin < sc.chrg.cpMax+1) /* what were RICHEDIT authors thinking ? */
1548     sc.seltyp |= SEL_MULTICHAR;
1549   TRACE("cpMin=%d cpMax=%d seltyp=%d (%s %s)\n",
1550     sc.chrg.cpMin, sc.chrg.cpMax, sc.seltyp,
1551     (sc.seltyp & SEL_TEXT) ? "SEL_TEXT" : "",
1552     (sc.seltyp & SEL_MULTICHAR) ? "SEL_MULTICHAR" : "");
1553   if (sc.chrg.cpMin != editor->notified_cr.cpMin || sc.chrg.cpMax != editor->notified_cr.cpMax)
1554   {
1555     ME_ClearTempStyle(editor);
1556
1557     editor->notified_cr = sc.chrg;
1558     ITextHost_TxNotify(editor->texthost, sc.nmhdr.code, &sc);
1559   }
1560 }
1561
1562 BOOL
1563 ME_ArrowKey(ME_TextEditor *editor, int nVKey, BOOL extend, BOOL ctrl)
1564 {
1565   int nCursor = 0;
1566   ME_Cursor *p = &editor->pCursors[nCursor];
1567   ME_Cursor tmp_curs = *p;
1568   BOOL success = FALSE;
1569
1570   ME_CheckCharOffsets(editor);
1571   switch(nVKey) {
1572     case VK_LEFT:
1573       editor->bCaretAtEnd = 0;
1574       if (ctrl)
1575         success = ME_MoveCursorWords(editor, &tmp_curs, -1);
1576       else
1577         success = ME_MoveCursorChars(editor, &tmp_curs, -1);
1578       break;
1579     case VK_RIGHT:
1580       editor->bCaretAtEnd = 0;
1581       if (ctrl)
1582         success = ME_MoveCursorWords(editor, &tmp_curs, +1);
1583       else
1584         success = ME_MoveCursorChars(editor, &tmp_curs, +1);
1585       break;
1586     case VK_UP:
1587       ME_MoveCursorLines(editor, &tmp_curs, -1);
1588       break;
1589     case VK_DOWN:
1590       ME_MoveCursorLines(editor, &tmp_curs, +1);
1591       break;
1592     case VK_PRIOR:
1593       ME_ArrowPageUp(editor, &tmp_curs);
1594       break;
1595     case VK_NEXT:
1596       ME_ArrowPageDown(editor, &tmp_curs);
1597       break;
1598     case VK_HOME: {
1599       if (ctrl)
1600         ME_ArrowCtrlHome(editor, &tmp_curs);
1601       else
1602         ME_ArrowHome(editor, &tmp_curs);
1603       editor->bCaretAtEnd = 0;
1604       break;
1605     }
1606     case VK_END:
1607       if (ctrl)
1608         ME_ArrowCtrlEnd(editor, &tmp_curs);
1609       else
1610         ME_ArrowEnd(editor, &tmp_curs);
1611       break;
1612   }
1613
1614   if (!extend)
1615     editor->pCursors[1] = tmp_curs;
1616   *p = tmp_curs;
1617
1618   ME_InvalidateSelection(editor);
1619   ME_Repaint(editor);
1620   ITextHost_TxShowCaret(editor->texthost, FALSE);
1621   ME_EnsureVisible(editor, &tmp_curs);
1622   ME_ShowCaret(editor);
1623   ME_SendSelChange(editor);
1624   return success;
1625 }