[phpeclipse.git] /

/*
 * Copyright (c) 2004 Christopher Lenz and others
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     Christopher Lenz - initial implementation
 * 
 * $Id: ProblemsLabelDecorator.java,v 1.1 2004-09-02 18:26:28 jsurfer Exp $
 */

package net.sourceforge.phpeclipse.ui.views.outline;

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

import net.sourceforge.phpeclipse.core.model.ISourceReference;
import net.sourceforge.phpeclipse.ui.WebUI;
import net.sourceforge.phpeclipse.ui.views.util.ImageDescriptorRegistry;
import net.sourceforge.phpeclipse.ui.views.util.ImageImageDescriptor;
import net.sourceforge.phpeclipse.ui.views.util.OverlayImageDescriptor;

import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.Position;
import org.eclipse.jface.text.source.Annotation;
import org.eclipse.jface.text.source.IAnnotationModel;
import org.eclipse.jface.viewers.ILabelDecorator;
import org.eclipse.jface.viewers.LabelProvider;
import org.eclipse.swt.graphics.Image;
import org.eclipse.ui.IEditorInput;
import org.eclipse.ui.texteditor.ITextEditor;

/**
 * Label decorator for the outline page that adds error and warning overlay
 * icons to elements in the outline. The information is retrieved from the 
 * annotation model corresponding to the input of the associated text editor.
 */
public class ProblemsLabelDecorator extends LabelProvider
        implements ILabelDecorator {

        // Constants ---------------------------------------------------------------

        private static final String ANNOTATION_TYPE_ERROR =
                "org.eclipse.ui.workbench.texteditor.error"; //$NON-NLS-1$

        private static final String ANNOTATION_TYPE_WARNING =
                "org.eclipse.ui.workbench.texteditor.warning"; //$NON-NLS-1$

        // Instance Variables ------------------------------------------------------

        /** The associated text editor if the decorator is used in the outline. */
        private ITextEditor editor;

        /** Registry of icons and overlay icons. */
        private ImageDescriptorRegistry registry = new ImageDescriptorRegistry();

        // Constructors ------------------------------------------------------------

        /**
         * Constructor.
         * 
         * @param editor the associated text editor
         */
        public ProblemsLabelDecorator(ITextEditor editor) {
                this.editor = editor;
        }

        // ILabelDecorator Implementation ------------------------------------------

        /* 
         * @see org.eclipse.jface.viewers.IBaseLabelProvider#dispose()
         */
        public void dispose() {
                super.dispose();
                registry.dispose();
        }

        /* 
         * @see ILabelDecorator#decorateImage(Image, Object)
         */
        public Image decorateImage(Image image, Object element) {
                Annotation annotations[] =
                        getAssociatedAnnotations((ISourceReference) element);
                ImageDescriptor overlay = null;
                for (int i = 0; i < annotations.length; i++) {
                        if (isError(annotations[i])) {
                                overlay = WebUI.getDefault().getImageRegistry().getDescriptor(
                                                WebUI.ICON_OVERLAY_ERROR);
                        } else if (isWarning(annotations[i])) {
                                overlay = WebUI.getDefault().getImageRegistry().getDescriptor(
                                                WebUI.ICON_OVERLAY_WARNING);
                        }
                }
                if (overlay != null) {
                        ImageDescriptor base = new ImageImageDescriptor(image);
                        return registry.get(new OverlayImageDescriptor(base,
                                        new ImageDescriptor[][] { null, null, { overlay }, null },
                                        null));
                } else {
                }
                return image;
        }

        /* 
         * @see ILabelDecorator#decorateText(String, Object)
         */
        public String decorateText(String text, Object element) {
                return text;
        }

        // Private Methods ---------------------------------------------------------

        /**
         * Returns all annotations associated with the given model element.
         * 
         * @param element the model element for which annotations should be
         *        collected
         * @return an array containing all annotations for the given element, or an
         *         empty array if no annotations are found
         */
        private Annotation[] getAssociatedAnnotations(ISourceReference element) {
                List retVal = new ArrayList();
                if (editor != null) {
                        IEditorInput input = editor.getEditorInput();
                        IAnnotationModel model =
                                editor.getDocumentProvider().getAnnotationModel(input);
                        for (Iterator i = model.getAnnotationIterator(); i.hasNext(); ) {
                                Annotation annotation = (Annotation) i.next();
                                Position pos = model.getPosition(annotation);
                                if (pos!=null && isInside(pos.getOffset(), element)) {
                                        retVal.add(annotation);
                                }
                        }
                }
                return (Annotation[]) retVal.toArray(new Annotation[retVal.size()]);
        }

        /**
         * Determines whether the given annotation is an error.
         * 
         * @param annotation the annotation to check
         * @return <tt>true</tt> if the annotation is to be displayed as an error,
         *         <tt>false</tt> otherwise
         */
        private boolean isError(Annotation annotation) {
                return ANNOTATION_TYPE_ERROR.equals(annotation.getType());
        }

        /**
         * Determines whether the given annotation is a warning.
         * 
         * @param annotation the annotation to check
         * @return <tt>true</tt> if the annotation is to be displayed as a warning,
         *         <tt>false</tt> otherwise
         */
        private boolean isWarning(Annotation annotation) {
                return ANNOTATION_TYPE_WARNING.equals(annotation.getType());
        }

        /**
         * Tests if the given position is inside the source region of a model
         * element.
         * 
         * @param pos the position to be tested
         * @param element the source element
         * @return boolean <tt>true</tt> if position is located inside the
         *         element, otherwise <tt>false</tt>
         */
        private boolean isInside(int pos, ISourceReference element) {
                IRegion region = element.getSourceRegion();
                if (region != null) {
                        int offset = region.getOffset();
                        return ((offset <= pos) && (offset + region.getLength() > pos));                        
                }
                return false;
        }

}