net.sourceforge.phpeclipse.ui/src/net/sourceforge/phpdt/internal/ui/text/HTMLTextPresenter.java

   1 package net.sourceforge.phpdt.internal.ui.text;
   2
   3 /*
   4  * (c) Copyright IBM Corp. 2000, 2001.
   5  * All Rights Reserved.
   6  */
   7
   8 import java.io.IOException;
   9 import java.io.Reader;
  10 import java.io.StringReader;
  11 import java.util.Iterator;
  12
  13 import net.sourceforge.phpdt.internal.ui.PHPUIMessages;
  14 import net.sourceforge.phpeclipse.ui.WebUI;
  15 //import net.sourceforge.phpeclipse.PHPeclipsePlugin;
  16
  17 import org.eclipse.jface.text.DefaultInformationControl;
  18 import org.eclipse.jface.text.Region;
  19 import org.eclipse.jface.text.TextPresentation;
  20 import org.eclipse.swt.custom.StyleRange;
  21 import org.eclipse.swt.graphics.GC;
  22 import org.eclipse.swt.widgets.Display;
  23
  24 public class HTMLTextPresenter implements
  25                 DefaultInformationControl.IInformationPresenter {
  26
  27         private static final String LINE_DELIM = System.getProperty(
  28                         "line.separator", "\n"); //$NON-NLS-1$ //$NON-NLS-2$
  29
  30         private int fCounter;
  31
  32         private boolean fEnforceUpperLineLimit;
  33
  34         public HTMLTextPresenter(boolean enforceUpperLineLimit) {
  35                 super();
  36                 fEnforceUpperLineLimit = enforceUpperLineLimit;
  37         }
  38
  39 //      public HTMLTextPresenter() {
  40 //              this(true);
  41 //      }
  42
  43         protected Reader createReader(String hoverInfo,
  44                         TextPresentation presentation) {
  45                 return new HTML2TextReader(new StringReader(hoverInfo), presentation);
  46         }
  47
  48         protected void adaptTextPresentation(TextPresentation presentation,
  49                         int offset, int insertLength) {
  50
  51                 int yoursStart = offset;
  52                 int yoursEnd = offset + insertLength - 1;
  53                 yoursEnd = Math.max(yoursStart, yoursEnd);
  54
  55                 Iterator e = presentation.getAllStyleRangeIterator();
  56                 while (e.hasNext()) {
  57
  58                         StyleRange range = (StyleRange) e.next();
  59
  60                         int myStart = range.start;
  61                         int myEnd = range.start + range.length - 1;
  62                         myEnd = Math.max(myStart, myEnd);
  63
  64                         if (myEnd < yoursStart)
  65                                 continue;
  66
  67                         if (myStart < yoursStart)
  68                                 range.length += insertLength;
  69                         else
  70                                 range.start += insertLength;
  71                 }
  72         }
  73
  74         private void append(StringBuffer buffer, String string,
  75                         TextPresentation presentation) {
  76
  77                 int length = string.length();
  78                 buffer.append(string);
  79
  80                 if (presentation != null)
  81                         adaptTextPresentation(presentation, fCounter, length);
  82
  83                 fCounter += length;
  84         }
  85
  86         private String getIndent(String line) {
  87                 int length = line.length();
  88
  89                 int i = 0;
  90                 while (i < length && Character.isWhitespace(line.charAt(i)))
  91                         ++i;
  92
  93                 return (i == length ? line : line.substring(0, i)) + " "; //$NON-NLS-1$
  94         }
  95
  96         /*
  97          * @see IHoverInformationPresenter#updatePresentation(Display display,
  98          *      String, TextPresentation, int, int)
  99          */
 100         public String updatePresentation(Display display, String hoverInfo,
 101                         TextPresentation presentation, int maxWidth, int maxHeight) {
 102
 103                 if (hoverInfo == null)
 104                         return null;
 105
 106                 GC gc = new GC(display);
 107                 try {
 108
 109                         StringBuffer buffer = new StringBuffer();
 110                         int maxNumberOfLines = Math.round(maxHeight
 111                                         / gc.getFontMetrics().getHeight());
 112
 113                         fCounter = 0;
 114                         LineBreakingReader reader = new LineBreakingReader(createReader(
 115                                         hoverInfo, presentation), gc, maxWidth);
 116
 117                         boolean lastLineFormatted = false;
 118                         String lastLineIndent = null;
 119
 120                         String line = reader.readLine();
 121                         boolean lineFormatted = reader.isFormattedLine();
 122                         boolean firstLineProcessed = false;
 123
 124                         while (line != null) {
 125
 126                                 if (fEnforceUpperLineLimit && maxNumberOfLines <= 0)
 127                                         break;
 128
 129                                 if (firstLineProcessed) {
 130                                         if (!lastLineFormatted)
 131                                                 append(buffer, LINE_DELIM, null);
 132                                         else {
 133                                                 append(buffer, LINE_DELIM, presentation);
 134                                                 if (lastLineIndent != null)
 135                                                         append(buffer, lastLineIndent, presentation);
 136                                         }
 137                                 }
 138
 139                                 append(buffer, line, null);
 140                                 firstLineProcessed = true;
 141
 142                                 lastLineFormatted = lineFormatted;
 143                                 if (!lineFormatted)
 144                                         lastLineIndent = null;
 145                                 else if (lastLineIndent == null)
 146                                         lastLineIndent = getIndent(line);
 147
 148                                 line = reader.readLine();
 149                                 lineFormatted = reader.isFormattedLine();
 150
 151                                 maxNumberOfLines--;
 152                         }
 153
 154                         if (line != null) {
 155                                 append(buffer, LINE_DELIM, lineFormatted ? presentation : null);
 156                                 append(buffer, PHPUIMessages
 157                                                 .getString("HTMLTextPresenter.ellipsis"), presentation); //$NON-NLS-1$
 158                         }
 159
 160                         return trim(buffer, presentation);
 161
 162                 } catch (IOException e) {
 163
 164                         WebUI.log(e);
 165                         return null;
 166
 167                 } finally {
 168                         gc.dispose();
 169                 }
 170         }
 171
 172         private String trim(StringBuffer buffer, TextPresentation presentation) {
 173
 174                 int length = buffer.length();
 175
 176                 int end = length - 1;
 177                 while (end >= 0 && Character.isWhitespace(buffer.charAt(end)))
 178                         --end;
 179
 180                 if (end == -1)
 181                         return ""; //$NON-NLS-1$
 182
 183                 if (end < length - 1)
 184                         buffer.delete(end + 1, length);
 185                 else
 186                         end = length;
 187
 188                 int start = 0;
 189                 while (start < end && Character.isWhitespace(buffer.charAt(start)))
 190                         ++start;
 191
 192                 buffer.delete(0, start);
 193                 presentation.setResultWindow(new Region(start, buffer.length()));
 194                 return buffer.toString();
 195         }
 196 }