core/plugins/org.eclipse.dltk.ui/src/org/eclipse/dltk/internal/ui/editor/ScriptAnnotationImageProvider.java

/*******************************************************************************
 * Copyright (c) 2000, 2017 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.editor;

import org.eclipse.dltk.ui.DLTKPluginImages;
import org.eclipse.dltk.ui.editor.IScriptAnnotation;
import org.eclipse.dltk.ui.editor.ScriptMarkerAnnotation;
import org.eclipse.dltk.ui.text.ScriptAnnotationUtils;
import org.eclipse.jface.resource.ImageDescriptor;
import org.eclipse.jface.resource.ImageRegistry;
import org.eclipse.jface.text.source.Annotation;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.widgets.Display;
import org.eclipse.ui.ISharedImages;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.texteditor.IAnnotationImageProvider;

/**
 * Image provider for annotations based on Java problem markers.
 *
 * @since 3.0
 */
public class ScriptAnnotationImageProvider implements IAnnotationImageProvider {

	private final static int NO_IMAGE = 0;
	private final static int GRAY_IMAGE = 1;
	private final static int OVERLAY_IMAGE = 2;
	private final static int QUICKFIX_IMAGE = 3;
	private final static int QUICKFIX_ERROR_IMAGE = 4;

	private static Image fgQuickFixImage;
	private static Image fgQuickFixErrorImage;
	private static ImageRegistry fgImageRegistry;

	private int fCachedImageType;
	private Image fCachedImage;

	public ScriptAnnotationImageProvider() {
	}

	@Override
	public Image getManagedImage(Annotation annotation) {
		if (annotation instanceof IScriptAnnotation) {
			IScriptAnnotation javaAnnotation = (IScriptAnnotation) annotation;
			int imageType = getImageType(javaAnnotation);
			return getImage(javaAnnotation, imageType, Display.getCurrent());
		}
		return null;
	}

	@Override
	public String getImageDescriptorId(Annotation annotation) {
		// unmanaged images are not supported
		return null;
	}

	@Override
	public ImageDescriptor getImageDescriptor(String symbolicName) {
		// unmanaged images are not supported
		return null;
	}

	private boolean showQuickFix(IScriptAnnotation annotation) {
		return annotation.isProblem()
				&& ScriptAnnotationUtils.hasCorrections(annotation);
	}

	private Image getQuickFixImage() {
		if (fgQuickFixImage == null)
			fgQuickFixImage = DLTKPluginImages
					.get(DLTKPluginImages.IMG_OBJS_FIXABLE_PROBLEM);
		return fgQuickFixImage;
	}

	private Image getQuickFixErrorImage() {
		if (fgQuickFixErrorImage == null)
			fgQuickFixErrorImage = DLTKPluginImages
					.get(DLTKPluginImages.IMG_OBJS_FIXABLE_ERROR);
		return fgQuickFixErrorImage;
	}

	private ImageRegistry getImageRegistry(Display display) {
		if (fgImageRegistry == null)
			fgImageRegistry = new ImageRegistry(display);
		return fgImageRegistry;
	}

	private int getImageType(IScriptAnnotation annotation) {
		int imageType = NO_IMAGE;
		if (annotation.hasOverlay())
			imageType = OVERLAY_IMAGE;
		else if (!annotation.isMarkedDeleted()) {
			if (showQuickFix(annotation))
				imageType = ScriptMarkerAnnotation.ERROR_ANNOTATION_TYPE
						.equals(annotation.getType()) ? QUICKFIX_ERROR_IMAGE
						: QUICKFIX_IMAGE;
		} else {
			imageType = GRAY_IMAGE;
		}
		return imageType;
	}

	private Image getImage(IScriptAnnotation annotation, int imageType,
			Display display) {
		if ((imageType == QUICKFIX_IMAGE || imageType == QUICKFIX_ERROR_IMAGE)
				&& fCachedImageType == imageType)
			return fCachedImage;

		Image image = null;
		switch (imageType) {
		case OVERLAY_IMAGE:
			IScriptAnnotation overlay = annotation.getOverlay();
			image = getManagedImage((Annotation) overlay);
			fCachedImageType = -1;
			break;
		case QUICKFIX_IMAGE:
			image = getQuickFixImage();
			fCachedImageType = imageType;
			fCachedImage = image;
			break;
		case QUICKFIX_ERROR_IMAGE:
			image = getQuickFixErrorImage();
			fCachedImageType = imageType;
			fCachedImage = image;
			break;
		case GRAY_IMAGE: {
			ISharedImages sharedImages = PlatformUI.getWorkbench()
					.getSharedImages();
			String annotationType = annotation.getType();
			if (ScriptMarkerAnnotation.ERROR_ANNOTATION_TYPE
					.equals(annotationType)) {
				image = sharedImages.getImage(ISharedImages.IMG_OBJS_ERROR_TSK);
			} else if (ScriptMarkerAnnotation.WARNING_ANNOTATION_TYPE
					.equals(annotationType)) {
				image = sharedImages.getImage(ISharedImages.IMG_OBJS_WARN_TSK);
			} else if (ScriptMarkerAnnotation.INFO_ANNOTATION_TYPE
					.equals(annotationType)) {
				image = sharedImages.getImage(ISharedImages.IMG_OBJS_INFO_TSK);
			}
			if (image != null) {
				ImageRegistry registry = getImageRegistry(display);
				String key = Integer.toString(image.hashCode());
				Image grayImage = registry.get(key);
				if (grayImage == null) {
					grayImage = new Image(display, image, SWT.IMAGE_GRAY);
					registry.put(key, grayImage);
				}
				image = grayImage;
			}
			fCachedImageType = -1;
			break;
		}
		}

		return image;
	}
}