/*******************************************************************************
* Copyright (c) 2000, 2015 QNX Software Systems and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* QNX Software Systems - Initial API and implementation
*******************************************************************************/
package org.eclipse.cdt.autotools.ui.editors;
import org.eclipse.core.runtime.Assert;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.TextPresentation;
import org.eclipse.jface.text.contentassist.IContextInformation;
import org.eclipse.jface.text.contentassist.IContextInformationPresenter;
import org.eclipse.jface.text.contentassist.IContextInformationValidator;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.StyleRange;
/**
* This class provides the macro call parameter parsing for the Autoconf Editor hover
* It is modified from the CDT class CParameterListValidator
*
* @author jjohnstn
*
*/
public class AutoconfMacroParameterListValidator implements IContextInformationValidator, IContextInformationPresenter {
private int fPosition;
private ITextViewer fViewer;
private IContextInformation fInformation;
private int fCurrentParameter;
public AutoconfMacroParameterListValidator() {
}
@Override
public void install(IContextInformation info, ITextViewer viewer, int documentPosition) {
fPosition= documentPosition;
fViewer= viewer;
fInformation= info;
fCurrentParameter= -1;
}
private int getStringEnd(IDocument d, int pos, int end, char ch) throws BadLocationException {
while (pos < end) {
char curr= d.getChar(pos);
pos++;
if (curr == '\\') {
// ignore escaped characters
pos++;
} else if (curr == ch) {
return pos;
}
}
return end;
}
private int getCharCount(IDocument document, int start, int end,
char increment, char decrement, boolean considerNesting) throws BadLocationException {
Assert.isTrue((increment != 0 || decrement != 0) && increment != decrement);
// There are two nesting levels to worry about. Arguments can be
// quoted with [] which means to treat the contents as one arg.
// As well, macro calls can be nested within macro calls so we
// have to handle parentheses.
int macroQuotingLevel = 0; // Pertaining to '[' and ']' quoted args.
int macroNestingLevel = -1; // Set to -1 to take into account first ( for function call
int charCount = 0;
while (start < end) {
char curr = document.getChar(start++);
switch (curr) {
case 'd':
if (start < end - 2) {
char next= document.getChar(start);
if (next == 'n') {
// a comment starts, advance to the comment end
next = document.getChar(start + 1);
if (next == 'l')
// dnl-comment: nothing to do anymore on this line
start= end;
}
}
break;
case '"':
case '\'':
start= getStringEnd(document, start, end, curr);
break;
default:
if ('[' == curr)
++ macroQuotingLevel;
else if (']' == curr)
-- macroQuotingLevel;
if (macroQuotingLevel != 0)
break;
if (considerNesting) {
if ('(' == curr)
++ macroNestingLevel;
else if (')' == curr) {
-- macroNestingLevel;
}
if (macroNestingLevel != 0)
break;
}
if (increment != 0) {
if (curr == increment) {
++charCount;
}
}
if (decrement != 0) {
if (curr == decrement) {
-- charCount;
}
}
}
}
return charCount;
}
@Override
public boolean isContextInformationValid(int position) {
try {
if (position < fPosition)
return false;
IDocument document= fViewer.getDocument();
IRegion line= document.getLineInformationOfOffset(fPosition);
if (position > line.getOffset() + line.getLength())
return false;
return (getCharCount(document, fPosition, position, '(', ')', false) >= 0);
} catch (BadLocationException x) {
return false;
}
}
@Override
public boolean updatePresentation(int position, TextPresentation presentation) {
int currentParameter= -1;
try {
currentParameter= getCharCount(fViewer.getDocument(), fPosition, position, ',', (char) 0, true);
} catch (BadLocationException x) {
return false;
}
if (fCurrentParameter != -1) {
if (currentParameter == fCurrentParameter)
return false;
}
presentation.clear();
fCurrentParameter= currentParameter;
//Don't presume what has been done to the string, rather use as is
String s= fInformation.getInformationDisplayString();
//@@@ This is obviously going to have problems with functions such
//int myfunction(int (*function_argument)(void * extra, int param), void * extra)
//int myfunction(/*A comment, indeed */int a);
int start= 0;
int occurrences= 0;
while (occurrences < fCurrentParameter) {
int found= s.indexOf(',', start);
if (found == -1)
break;
start= found + 1;
++ occurrences;
}
if (occurrences < fCurrentParameter) {
presentation.addStyleRange(new StyleRange(0, s.length(), null, null, SWT.NORMAL));
return true;
}
if (start == -1)
start= 0;
int end= s.indexOf(',', start);
if (end == -1)
end= s.length();
if (start > 0)
presentation.addStyleRange(new StyleRange(0, start, null, null, SWT.NORMAL));
if (end > start)
presentation.addStyleRange(new StyleRange(start, end - start, null, null, SWT.BOLD));
if (end < s.length())
presentation.addStyleRange(new StyleRange(end, s.length() - end, null, null, SWT.NORMAL));
return true;
}
}