dlls/riched20/row.c

   1 /*
   2  * RichEdit - Operations on rows of text (rows are recreated during
   3  * wrapping and are used for displaying the document, they don't keep any
   4  * true document content; delete all rows, rewrap all paragraphs and
   5  * you get them back).
   6  *
   7  * Copyright 2004 by Krzysztof Foltman
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2.1 of the License, or (at your option) any later version.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  22  */
  23
  24
  25 #include "editor.h"
  26
  27 ME_DisplayItem *ME_FindRowStart(ME_Context *c, ME_DisplayItem *item,
  28                                 int nRelPos) {
  29   ME_DisplayItem *para = ME_GetParagraph(item);
  30   ME_MustBeWrapped(c, para);
  31   if(nRelPos<=0) { /* if this or preceding row */
  32     do {
  33       ME_DisplayItem *item2 = ME_FindItemBack(item, diStartRowOrParagraph);
  34       if (item2->type == diParagraph)
  35       {
  36         if (item2->member.para.prev_para == NULL)
  37           return item;
  38         /* if skipping to the preceding paragraph, ensure it's wrapped */
  39         ME_MustBeWrapped(c, item2->member.para.prev_para);
  40         item = item2;
  41         continue;
  42       }
  43       else if (item2->type == diStartRow)
  44       {
  45         nRelPos++;
  46         if (nRelPos>0)
  47           return item;
  48         item = item2;
  49         continue;
  50       }
  51       assert(0 == "bug in FindItemBack(item, diStartRowOrParagraph)");
  52       item = item2;
  53     } while(1);
  54   }
  55   while(nRelPos>0) { /* if one of the next rows */
  56     ME_DisplayItem *item2 = ME_FindItemFwd(item, diStartRowOrParagraph);
  57     if (!item2)
  58       return item;
  59     if (item2->type == diParagraph)
  60     {
  61       if (item2->member.para.next_para == NULL)
  62         return item;
  63       continue;
  64     }
  65     item = item2;
  66     nRelPos--;
  67   }
  68   return item;
  69 }
  70
  71 /* I'm sure these functions would simplify some code in caret ops etc,
  72  * I just didn't remember them when I wrote that code
  73  */
  74
  75 ME_DisplayItem *ME_RowStart(ME_DisplayItem *item) {
  76   return ME_FindItemBackOrHere(item, diStartRow);
  77 }
  78
  79 /*
  80 ME_DisplayItem *ME_RowEnd(ME_DisplayItem *item) {
  81   ME_DisplayItem *item2 = ME_FindItemFwd(item, diStartRowOrParagraphOrEnd);
  82   if (!item2) return NULL;
  83   return ME_FindItemBack(item, diRun);
  84 }
  85 */
  86
  87 ME_DisplayItem *
  88 ME_FindRowWithNumber(ME_TextEditor *editor, int nRow)
  89 {
  90   ME_DisplayItem *item = ME_FindItemFwd(editor->pBuffer->pFirst, diParagraph);
  91   int nCount = 0;
  92
  93   while (item && nCount + item->member.para.nRows <= nRow)
  94   {
  95     nCount += item->member.para.nRows;
  96     item = ME_FindItemFwd(item, diParagraph);
  97   }
  98   if (!item)
  99     return item;
 100   for (item = ME_FindItemFwd(item, diStartRow); item && nCount < nRow; nCount++)
 101     item = ME_FindItemFwd(item, diStartRow);
 102   return item;
 103 }
 104
 105
 106 int
 107 ME_RowNumberFromCharOfs(ME_TextEditor *editor, int nOfs)
 108 {
 109   ME_DisplayItem *item = editor->pBuffer->pFirst->next;
 110   int nRow = 0;
 111
 112   while (item && item->member.para.next_para->member.para.nCharOfs <= nOfs)
 113   {
 114     nRow += item->member.para.nRows;
 115     item = ME_FindItemFwd(item, diParagraph);
 116   }
 117   if (item)
 118   {
 119     ME_DisplayItem *next_para = item->member.para.next_para;
 120
 121     nOfs -= item->member.para.nCharOfs;
 122     item = ME_FindItemFwd(item, diRun);
 123     while ((item = ME_FindItemFwd(item, diStartRowOrParagraph)) != NULL)
 124     {
 125       if (item == next_para)
 126         break;
 127       item = ME_FindItemFwd(item, diRun);
 128       if (item->member.run.nCharOfs > nOfs)
 129         break;
 130       nRow++;
 131     }
 132   }
 133   return nRow;
 134 }