core/plugins/org.eclipse.dltk.ui/src/org/eclipse/dltk/internal/ui/search/SearchLabelProvider.java

/*******************************************************************************
 * Copyright (c) 2000, 2007 IBM Corporation 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
 *
 
 *******************************************************************************/
package org.eclipse.dltk.internal.ui.search;

import java.util.HashMap;
import java.util.Map;

import org.eclipse.core.runtime.preferences.InstanceScope;
import org.eclipse.dltk.core.DLTKCore;
import org.eclipse.dltk.core.search.SearchMatch;
import org.eclipse.dltk.internal.corext.util.Messages;
import org.eclipse.dltk.ui.DLTKUIPlugin;
import org.eclipse.dltk.ui.ProblemsLabelDecorator;
import org.eclipse.dltk.ui.ScriptElementLabels;
import org.eclipse.dltk.ui.search.IMatchPresentation;
import org.eclipse.dltk.ui.viewsupport.AppearanceAwareLabelProvider;
import org.eclipse.jface.preference.PreferenceConverter;
import org.eclipse.jface.util.IPropertyChangeListener;
import org.eclipse.jface.util.PropertyChangeEvent;
import org.eclipse.jface.viewers.ILabelProvider;
import org.eclipse.jface.viewers.ILabelProviderListener;
import org.eclipse.jface.viewers.LabelProviderChangedEvent;
import org.eclipse.search.ui.NewSearchUI;
import org.eclipse.search.ui.text.AbstractTextSearchResult;
import org.eclipse.search.ui.text.Match;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.ui.preferences.ScopedPreferenceStore;

public abstract class SearchLabelProvider extends AppearanceAwareLabelProvider {

	public static final String PROPERTY_MATCH_COUNT = "org.eclipse.dltk.search.matchCount"; //$NON-NLS-1$

	// copied from SearchPreferencePage
	private static final String EMPHASIZE_POTENTIAL_MATCHES = "org.eclipse.search.potentialMatch.emphasize"; //$NON-NLS-1$
	private static final String POTENTIAL_MATCH_FG_COLOR = "org.eclipse.search.potentialMatch.fgColor"; //$NON-NLS-1$

	protected static final long DEFAULT_SEARCH_TEXTFLAGS = (DEFAULT_TEXTFLAGS | ScriptElementLabels.P_COMPRESSED)
			& ~ScriptElementLabels.M_APP_RETURNTYPE;
	protected static final int DEFAULT_SEARCH_IMAGEFLAGS = DEFAULT_IMAGEFLAGS;

	private Color fPotentialMatchFgColor;
	private Map<IMatchPresentation, ILabelProvider> fLabelProviderMap;

	protected DLTKSearchResultPage fPage;

	private ScopedPreferenceStore fSearchPreferences;
	private IPropertyChangeListener fSearchPropertyListener;

	public SearchLabelProvider(DLTKSearchResultPage page) {
		super(DEFAULT_SEARCH_TEXTFLAGS, DEFAULT_SEARCH_IMAGEFLAGS, DLTKUIPlugin
				.getDefault().getPreferenceStore());
		if (DLTKCore.DEBUG) {
			System.out
					.println("TODO: Add language dependent preference store support here..."); //$NON-NLS-1$
		}
		addLabelDecorator(new ProblemsLabelDecorator());

		fPage = page;
		fLabelProviderMap = new HashMap<IMatchPresentation, ILabelProvider>(5);

		fSearchPreferences = new ScopedPreferenceStore(InstanceScope.INSTANCE,
				NewSearchUI.PLUGIN_ID);
		fSearchPropertyListener = new IPropertyChangeListener() {
			public void propertyChange(PropertyChangeEvent event) {
				doSearchPropertyChange(event);
			}
		};
		fSearchPreferences.addPropertyChangeListener(fSearchPropertyListener);
	}

	final void doSearchPropertyChange(PropertyChangeEvent event) {
		if (fPotentialMatchFgColor == null)
			return;
		if (POTENTIAL_MATCH_FG_COLOR.equals(event.getProperty())
				|| EMPHASIZE_POTENTIAL_MATCHES.equals(event.getProperty())) {
			fPotentialMatchFgColor.dispose();
			fPotentialMatchFgColor = null;
			LabelProviderChangedEvent lpEvent = new LabelProviderChangedEvent(
					SearchLabelProvider.this, null); // refresh all
			fireLabelProviderChanged(lpEvent);
		}
	}

	@Override
	public Color getForeground(Object element) {
		if (arePotentialMatchesEmphasized()) {
			if (getNumberOfPotentialMatches(element) > 0)
				return getForegroundColor();
		}
		return super.getForeground(element);
	}

	private Color getForegroundColor() {
		if (fPotentialMatchFgColor == null) {
			fPotentialMatchFgColor = new Color(DLTKUIPlugin
					.getActiveWorkbenchShell().getDisplay(),
					getPotentialMatchForegroundColor());
		}
		return fPotentialMatchFgColor;
	}

	protected final int getNumberOfPotentialMatches(Object element) {
		int res = 0;
		AbstractTextSearchResult result = fPage.getInput();
		if (result != null) {
			Match[] matches = result.getMatches(element);
			for (int i = 0; i < matches.length; i++) {
				if ((matches[i]) instanceof DLTKElementMatch) {
					if (((DLTKElementMatch) matches[i]).getAccuracy() == SearchMatch.A_INACCURATE)
						res++;
				}
			}
		}
		return res;
	}

	protected final String getLabelWithCounts(Object element, String elementName) {
		int matchCount = fPage.getDisplayedMatchCount(element);
		int potentialCount = getNumberOfPotentialMatches(element);

		if (matchCount < 2) {
			if (matchCount == 1 && hasChildren(element)) {
				if (potentialCount > 0)
					return Messages
							.format(
									SearchMessages.SearchLabelProvider_potential_singular,
									elementName);
				return Messages.format(
						SearchMessages.SearchLabelProvider_exact_singular,
						elementName);
			}
			if (potentialCount > 0)
				return Messages.format(
						SearchMessages.SearchLabelProvider_potential_noCount,
						elementName);
			return Messages.format(
					SearchMessages.SearchLabelProvider_exact_noCount,
					elementName);
		} else {
			int exactCount = matchCount - potentialCount;

			if (potentialCount > 0 && exactCount > 0) {
				String[] args = new String[] { elementName,
						String.valueOf(matchCount), String.valueOf(exactCount),
						String.valueOf(potentialCount) };
				return Messages
						.format(
								SearchMessages.SearchLabelProvider_exact_and_potential_plural,
								args);
			} else if (exactCount == 0) {
				String[] args = new String[] { elementName,
						String.valueOf(matchCount) };
				return Messages.format(
						SearchMessages.SearchLabelProvider_potential_plural,
						args);
			}
			String[] args = new String[] { elementName,
					String.valueOf(matchCount) };
			return Messages.format(
					SearchMessages.SearchLabelProvider_exact_plural, args);
		}
	}

	protected boolean hasChildren(Object elem) {
		return false;
	}

	@Override
	public void dispose() {
		if (fPotentialMatchFgColor != null) {
			fPotentialMatchFgColor.dispose();
			fPotentialMatchFgColor = null;
		}
		fSearchPreferences
				.removePropertyChangeListener(fSearchPropertyListener);
		for (ILabelProvider labelProvider : fLabelProviderMap.values()) {
			labelProvider.dispose();
		}
		fSearchPreferences = null;
		fSearchPropertyListener = null;
		fLabelProviderMap.clear();

		super.dispose();
	}

	@Override
	public void addListener(ILabelProviderListener listener) {
		super.addListener(listener);
		for (ILabelProvider labelProvider : fLabelProviderMap.values()) {
			labelProvider.addListener(listener);
		}
	}

	@Override
	public boolean isLabelProperty(Object element, String property) {
		if (PROPERTY_MATCH_COUNT.equals(property))
			return true;
		return getLabelProvider(element).isLabelProperty(element, property);
	}

	@Override
	public void removeListener(ILabelProviderListener listener) {
		super.removeListener(listener);
		for (ILabelProvider labelProvider : fLabelProviderMap.values()) {
			labelProvider.removeListener(listener);
		}
	}

	protected String getParticipantText(Object element) {
		ILabelProvider labelProvider = getLabelProvider(element);
		if (labelProvider != null)
			return labelProvider.getText(element);
		return ""; //$NON-NLS-1$

	}

	protected Image getParticipantImage(Object element) {
		ILabelProvider lp = getLabelProvider(element);
		if (lp == null)
			return null;
		return lp.getImage(element);
	}

	private ILabelProvider getLabelProvider(Object element) {
		IMatchPresentation participant = ((DLTKSearchResult) fPage.getInput())
				.getSearchParticpant(element);
		if (participant == null)
			return null;

		ILabelProvider lp = fLabelProviderMap.get(participant);
		if (lp == null) {
			lp = participant.createLabelProvider();
			fLabelProviderMap.put(participant, lp);

			Object[] listeners = fListeners.getListeners();
			for (int i = 0; i < listeners.length; i++) {
				lp.addListener((ILabelProviderListener) listeners[i]);
			}
		}
		return lp;
	}

	private boolean arePotentialMatchesEmphasized() {
		return fSearchPreferences.getBoolean(EMPHASIZE_POTENTIAL_MATCHES);
	}

	private RGB getPotentialMatchForegroundColor() {
		return PreferenceConverter.getColor(fSearchPreferences,
				POTENTIAL_MATCH_FG_COLOR);
	}
}