Popup.java

/*******************************************************************************
 * Copyright (c) Gil Barash - chookapp@yahoo.com
 * 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:
 *    Gil Barash - initial API and implementation
 *******************************************************************************/
package com.chookapp.org.bracketeer.core;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.Document;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.Position;
import org.eclipse.jface.text.Region;
import org.eclipse.jface.text.source.ISourceViewer;
import org.eclipse.jface.text.source.SourceViewer;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.StyleRange;
import org.eclipse.swt.custom.StyledText;
import org.eclipse.swt.events.PaintEvent;
import org.eclipse.swt.events.PaintListener;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.ui.services.IDisposable;

public class Popup implements IDisposable, PaintListener
{
    private Shell _shell;
    private SourceViewer _sourceViewer;
    private PaintableBracket _bracketToPaint;

    public Popup(final ISourceViewer parentSv, final StyledText parentSt, 
                 IDocument origDoc, PaintableBracket paintBracket) throws BadLocationException
    {
        _bracketToPaint = null;
        
        _shell = new Shell(parentSt.getShell(), SWT.NO_FOCUS | SWT.ON_TOP | SWT.TOOL);
        _shell.setLayout(new FillLayout());
        
    
        Composite inner = new Composite(_shell, SWT.NONE);
        inner.setLayout(new FillLayout());
        
        _sourceViewer = new SourceViewer(inner, null, null, false, SWT.MULTI);                
        
        _sourceViewer.setEditable(false);
        StyledText textWidget = _sourceViewer.getTextWidget();
        textWidget.setFont(parentSt.getFont());
        textWidget.setTabs(parentSt.getTabs());
        textWidget.setForeground(parentSt.getForeground());
        textWidget.setBackground(parentSt.getBackground());
        textWidget.addPaintListener(this);
        
        GC gc = new GC(textWidget);
        int popupHight = 70;
        try
        {
            popupHight = gc.getFontMetrics().getHeight() * 3;
        }
        finally
        {
            gc.dispose();
        }
        
        try
        {
            updatePopupContent(_sourceViewer, parentSv, parentSt, origDoc, paintBracket);
        }
        catch (BadLocationException e)
        {
            dispose();
            throw e;
        }
        
        Point txtSize = new Point(parentSt.getSize().x, popupHight);
        
        _shell.setSize(txtSize);
        Point parentLocation = parentSt.getDisplay().map(parentSt, null, 0, 0);
        _shell.setLocation(parentLocation.x, parentLocation.y - txtSize.y);

        _shell.setVisible(true);
    }


    private void updatePopupContent(SourceViewer sv, final ISourceViewer parentSv, final StyledText parentSt, 
                                    IDocument origDoc, PaintableBracket paintBracket) throws BadLocationException
    {
        Document newDoc = new Document();
        sv.setInput(newDoc);
        
        String txt = ""; //$NON-NLS-1$
        List<StyleRange> styleRanges = new ArrayList<StyleRange>();
    
        Position origPos = paintBracket.getPosition();
    
        Integer[] lines = new Integer[3];        
        lines[1] = origDoc.getLineOfOffset(origPos.getOffset()); 
        lines[0] = getLineBefore(origDoc, lines[1]);
        lines[2] = getLineAfter(origDoc, lines[1]);

        for(int i = 0; i < 3; i++)
        {
            if(lines[i] == null)
                continue;
            int line = lines[i];
            
            if( !txt.isEmpty() )
                txt += "\r\n"; //$NON-NLS-1$
            
            int newDocOffset = txt.length();
            IRegion region = origDoc.getLineInformation(line);
            txt += origDoc.get(region.getOffset(), region.getLength());
            if(i == 1)
            {
                Position newPos = new Position((origPos.getOffset() - region.getOffset()) + newDocOffset, 1);
                _bracketToPaint = paintBracket.clone(newPos);
            }
            
            region = TextUtils.getWidgetRange(parentSv, region.getOffset(), region.getLength());
            
            StyleRange[] ranges = parentSt.getStyleRanges(region.getOffset(), region.getLength());
            for (StyleRange styleRange : ranges)
            {
                styleRange.start = newDocOffset;
                newDocOffset += styleRange.length;
                styleRanges.add(styleRange);
            }                                
        }
        
        sv.getDocument().set(txt);
        sv.setDocument(newDoc);
        StyleRange[] stArray = new StyleRange[styleRanges.size()];
        styleRanges.toArray(stArray);
        sv.getTextWidget().setStyleRanges(stArray);
        
    }
    

    private Integer getLineBefore(IDocument origDoc, int startFromLine) throws BadLocationException
    {
        for(int line = startFromLine-1; line >= 0; line--)
        {
            IRegion region = origDoc.getLineInformation(line);
            String txt = origDoc.get(region.getOffset(), region.getLength());
            if(!txt.trim().isEmpty())
                return line;
        }
        return null;
    }

    private Integer getLineAfter(IDocument origDoc, int startFromLine) throws BadLocationException
    {
        int linesCount = origDoc.getNumberOfLines();
        for(int line = startFromLine+1; line < linesCount; line++)
        {
            IRegion region = origDoc.getLineInformation(line);
            String txt = origDoc.get(region.getOffset(), region.getLength());
            if(!txt.trim().isEmpty())
                return line;
        }
        return null;
    }


    @Override
    public void dispose()
    {
        _shell.close();
        _shell.dispose();
    }


    @Override
    public void paintControl(PaintEvent event)
    {
        if(_bracketToPaint == null)
            return;
        
        _bracketToPaint.paint(event.gc, _sourceViewer.getTextWidget(), 
                              _sourceViewer.getDocument(),
                              new Region(_bracketToPaint.getPosition().getOffset(), 
                                         _bracketToPaint.getPosition().getLength()),
                              null);
    }
}