StyledTextSource.java

/******************************************************************************* 
 * Copyright (c) 2008 xored software, Inc.  
 * 
 * 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: 
 *     xored software, Inc. - initial API and Implementation (Yuri Strot) 
 *******************************************************************************/
package com.xored.glance.ui.controls.text.styled;

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

import org.eclipse.swt.custom.StyleRange;
import org.eclipse.swt.custom.StyledText;
import org.eclipse.swt.graphics.Color;

import com.xored.glance.ui.sources.ColorManager;
import com.xored.glance.ui.sources.Match;

/**
 * @author Yuri Strot
 * 
 */
public class StyledTextSource extends AbstractStyledTextSource {

	public StyledTextSource(final StyledText text) {
		super(text);
	}

	@Override
	protected void doDispose() {
		super.doDispose();
        clearAll();
    }

    protected void clearAll() {
        clearHighlight();
        clearSelected();
	}
	protected void clearHighlight() {
		if (previous != null && previous.length > 0) {
			for (int i = 0; i < previous.length; i++) {
				clearRangeGroup(previous[i]);
			}
		}
		previous = null;
	}
	
    protected void clearSelected() {
        if (selectedRange != null) {
            clearRangeGroup(selectedRange);
            selectedRange = null;
        }
    }

	private void clearRangeGroup(final RangeGroup group){
	    getText().replaceStyleRanges(group.getStart(),
            group.getEnd() - group.getStart(), new StyleRange[0]);
	    final StyleRange[] ranges = group.getRanges();
	    for (final StyleRange range : ranges) {
	        getText().replaceStyleRanges(range.start, range.length,
                new StyleRange[] { range });
	    }
	}

	@Override
	public void select(final Match match) {
	    super.select(match);
        clearSelected();
        if (match != null) {
            final List<StyleRange> ranges = createRanges(match, ColorManager.getInstance()
                .getSelectedBackgroundColor());
            selectedRange = new RangeGroup(match.getOffset(), match.getOffset() + match.getLength(),
                ranges.toArray(new StyleRange[ranges.size()]));
        }
	}
	
	public void show(final Match[] matches) {
        clearAll();
        previous = new RangeGroup[matches.length];
		for (int i = 0; i < matches.length; i++) {
			final Match match = matches[i];
            final List<StyleRange> ranges = createRanges(match, ColorManager.getInstance()
                .getBackgroundColor());
            previous[i] = new RangeGroup(match.getOffset(), match.getOffset() + match.getLength(),
                ranges
					.toArray(new StyleRange[ranges.size()]));
		}

        if (selected != null) {
            select(selected);
        }
	}

    private List<StyleRange> createRanges(final Match match, final Color bg) {
        int index = match.getOffset();
        final int lastIndex = index + match.getLength();
        final StyleRange[] matchRanges = getText().getStyleRanges(index, match.getLength());
        final List<StyleRange> ranges = new ArrayList<StyleRange>();
        for (final StyleRange styleRange : matchRanges) {
            ranges.add(styleRange);
            if (styleRange.length < 0) {
                continue;
            }
            final StyleRange newStyleRange = new StyleRange(styleRange.start, styleRange.length, null, bg,
                styleRange.fontStyle);
            if (styleRange.start - index > 0)
                getText().replaceStyleRanges(index, styleRange.start - index,
                    new StyleRange[] { newStyleRange });
            getText().replaceStyleRanges(styleRange.start, styleRange.length,
                new StyleRange[] { newStyleRange });
            index = styleRange.start + styleRange.length;
        }
        if (lastIndex - index > 0) {
            final StyleRange newStyleRange = new StyleRange(index, lastIndex - index, null, bg);
            getText().replaceStyleRanges(index, lastIndex - index, new StyleRange[] { newStyleRange });
        }
        return ranges;
    }

	private RangeGroup[] previous;
	private RangeGroup selectedRange;
}