/*
* Code borrowed from PyDev
*/
/*
* @author Fabio Zadrozny Created: June 2004 License: Common Public License v1.0
*/
package org.erlide.ui.internal.information;
import java.io.IOException;
import java.io.Reader;
import java.io.StringReader;
import java.util.Iterator;
import org.eclipse.jface.text.DefaultInformationControl;
import org.eclipse.jface.text.Region;
import org.eclipse.jface.text.TextPresentation;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.StyleRange;
import org.eclipse.swt.graphics.Drawable;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.widgets.Display;
import org.erlide.ui.util.UIStringUtils;
import org.erlide.ui.util.eclipse.text.LineBreakingReader;
import org.erlide.util.StringUtils;
/**
* Based on HTMLTextPresenter
*
* @author Fabio
*/
public class ErlInformationPresenter
implements DefaultInformationControl.IInformationPresenter,
DefaultInformationControl.IInformationPresenterExtension {
public static final String LINE_DELIM = System.getProperty("line.separator", "\n"); //$NON-NLS-1$ //$NON-NLS-2$
private int fCounter;
private final boolean fEnforceUpperLineLimit;
public ErlInformationPresenter(final boolean enforceUpperLineLimit) {
super();
fEnforceUpperLineLimit = enforceUpperLineLimit;
}
public ErlInformationPresenter() {
this(true);
}
/**
* Creates the reader and properly puts the presentation into place.
*/
protected Reader createReader(final String hoverInfo,
final TextPresentation presentation) {
String str = UIStringUtils.removeWhitespaceColumnsToLeft(hoverInfo);
str = correctLineDelimiters(str);
str = makeEdocBold(presentation, str);
return new StringReader(str);
}
/**
* The line delimiters must match the platform for the bolds to be correct, so, in
* this function we remove the ones existing and add the ones dependent on the
* platform
*/
private String correctLineDelimiters(final String str) {
final StringBuffer buf = new StringBuffer();
for (String s : StringUtils.splitLines(str)) {
boolean found = false;
while (s.endsWith("\r") || s.endsWith("\n")) {
found = true;
s = s.substring(0, s.length() - 1);
}
buf.append(s);
if (found) {
buf.append(LINE_DELIM);
}
}
return buf.toString();
}
/**
* Changes the @xxx bbb: things for bold
*/
private String makeEdocBold(final TextPresentation presentation, final String str) {
int lastIndex = 0;
// 1st, let's mark in bold the things generated in edoc.
while (true) {
final int start = str.indexOf('@', lastIndex);
if (start == -1) {
break;
}
int end = start + 1;
while (end < str.length()) {
if (!(str.charAt(end) == ':')) {
end++;
} else {
break;
}
}
if (end == start) {
break;
}
lastIndex = end;
presentation.addStyleRange(
new StyleRange(start, end - start, null, null, SWT.BOLD));
}
// return the input (this one doesn't change the string)
return str;
}
protected void adaptTextPresentation(final TextPresentation presentation,
final int offset, final int insertLength) {
final int yoursStart = offset;
int yoursEnd = offset + insertLength - 1;
yoursEnd = Math.max(yoursStart, yoursEnd);
@SuppressWarnings("unchecked")
final Iterator<StyleRange> e = presentation.getAllStyleRangeIterator();
while (e.hasNext()) {
final StyleRange range = e.next();
final int myStart = range.start;
int myEnd = range.start + range.length - 1;
myEnd = Math.max(myStart, myEnd);
if (myEnd < yoursStart) {
continue;
}
if (myStart < yoursStart) {
range.length += insertLength;
} else {
range.start += insertLength;
}
}
}
private void append(final StringBuffer buffer, final String string,
final TextPresentation presentation) {
final int length = string.length();
buffer.append(string);
if (presentation != null) {
adaptTextPresentation(presentation, fCounter, length);
}
fCounter += length;
}
private String getIndent(final String line) {
final int length = line.length();
int i = 0;
while (i < length && Character.isWhitespace(line.charAt(i))) {
++i;
}
return (i == length ? line : line.substring(0, i)) + " "; //$NON-NLS-1$
}
@Deprecated
@Override
public String updatePresentation(final Display display, final String hoverInfo,
final TextPresentation presentation, final int maxWidth,
final int maxHeight) {
return updatePresentation((Drawable) display, hoverInfo, presentation, maxWidth,
maxHeight);
}
/*
* @see IHoverInformationPresenterExtension#updatePresentation(Drawable drawable,
* String, TextPresentation, int, int)
*
* @since 3.2
*/
@Override
public String updatePresentation(final Drawable drawable, final String hoverInfo,
final TextPresentation presentation, final int maxWidth,
final int maxHeight) {
if (hoverInfo == null) {
return null;
}
final GC gc = new GC(drawable);
try {
final StringBuffer buffer = new StringBuffer();
int maxNumberOfLines = Math
.round((float) maxHeight / (float) gc.getFontMetrics().getHeight());
fCounter = 0;
final LineBreakingReader reader = new LineBreakingReader(
createReader(hoverInfo, presentation), gc, maxWidth);
boolean lastLineFormatted = false;
String lastLineIndent = null;
String line = reader.readLine();
boolean lineFormatted = reader.isFormattedLine();
boolean firstLineProcessed = false;
while (line != null) {
if (fEnforceUpperLineLimit && maxNumberOfLines <= 0) {
break;
}
if (firstLineProcessed) {
if (!lastLineFormatted) {
append(buffer, LINE_DELIM, null);
} else {
append(buffer, LINE_DELIM, presentation);
if (lastLineIndent != null) {
append(buffer, lastLineIndent, presentation);
}
}
}
append(buffer, line, null);
firstLineProcessed = true;
lastLineFormatted = lineFormatted;
if (!lineFormatted) {
lastLineIndent = null;
} else if (lastLineIndent == null) {
lastLineIndent = getIndent(line);
}
line = reader.readLine();
lineFormatted = reader.isFormattedLine();
maxNumberOfLines--;
}
if (line != null) {
append(buffer, LINE_DELIM, lineFormatted ? presentation : null);
}
return trim(buffer, presentation);
} catch (final IOException e) {
// ignore TODO do something else?
return null;
} finally {
gc.dispose();
}
}
private String trim(final StringBuffer buffer, final TextPresentation presentation) {
final int length = buffer.length();
int end = length - 1;
while (end >= 0 && Character.isWhitespace(buffer.charAt(end))) {
--end;
}
if (end == -1) {
return ""; //$NON-NLS-1$
}
if (end < length - 1) {
buffer.delete(end + 1, length);
} else {
end = length;
}
int start = 0;
while (start < end && Character.isWhitespace(buffer.charAt(start))) {
++start;
}
buffer.delete(0, start);
presentation.setResultWindow(new Region(start, buffer.length()));
return buffer.toString();
}
}