/*******************************************************************************
* Copyright (c) 2004, 2010 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
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.wst.html.ui.internal.contentassist;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.ITextSelection;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.Region;
import org.eclipse.jface.text.contentassist.ICompletionProposal;
import org.eclipse.jface.text.templates.ContextTypeRegistry;
import org.eclipse.jface.text.templates.Template;
import org.eclipse.jface.text.templates.TemplateCompletionProcessor;
import org.eclipse.jface.text.templates.TemplateContext;
import org.eclipse.jface.text.templates.TemplateContextType;
import org.eclipse.jface.text.templates.TemplateException;
import org.eclipse.jface.text.templates.TemplateProposal;
import org.eclipse.jface.text.templates.persistence.TemplateStore;
import org.eclipse.swt.graphics.Image;
import org.eclipse.wst.html.ui.internal.HTMLUIPlugin;
import org.eclipse.wst.html.ui.internal.editor.HTMLEditorPluginImageHelper;
import org.eclipse.wst.html.ui.internal.editor.HTMLEditorPluginImages;
import org.eclipse.wst.xml.ui.internal.contentassist.ReplaceNameTemplateContext;
/**
* <p>Completion computer for HTML templates</p>
*/
public class HTMLTemplateCompletionProcessor extends TemplateCompletionProcessor {
private static final class ProposalComparator implements Comparator {
public int compare(Object o1, Object o2) {
return ((TemplateProposal) o2).getRelevance() - ((TemplateProposal) o1).getRelevance();
}
}
private static final Comparator fgProposalComparator = new ProposalComparator();
private String fContextTypeId = null;
/*
* Copied from super class except instead of calling createContext(viewer,
* region) call createContext(viewer, region, offset) instead
*/
public ICompletionProposal[] computeCompletionProposals(ITextViewer viewer, int offset) {
ITextSelection selection = (ITextSelection) viewer.getSelectionProvider().getSelection();
// adjust offset to end of normalized selection
if (selection.getOffset() == offset)
offset = selection.getOffset() + selection.getLength();
String prefix = extractPrefix(viewer, offset);
Region region = new Region(offset - prefix.length(), prefix.length());
TemplateContext context = createContext(viewer, region, offset);
if (context == null)
return new ICompletionProposal[0];
// name of the selection variables {line, word}_selection
context.setVariable("selection", selection.getText()); //$NON-NLS-1$
Template[] templates = getTemplates(context.getContextType().getId());
List matches = new ArrayList();
for (int i = 0; i < templates.length; i++) {
Template template = templates[i];
try {
context.getContextType().validate(template.getPattern());
}
catch (TemplateException e) {
continue;
}
if (template.matches(prefix, context.getContextType().getId()))
matches.add(createProposal(template, context, (IRegion) region, getRelevance(template, prefix)));
}
Collections.sort(matches, fgProposalComparator);
return (ICompletionProposal[]) matches.toArray(new ICompletionProposal[matches.size()]);
}
/**
* Creates a concrete template context for the given region in the
* document. This involves finding out which context type is valid at the
* given location, and then creating a context of this type. The default
* implementation returns a <code>SmartReplaceTemplateContext</code> for
* the context type at the given location. This takes the offset at which
* content assist was invoked into consideration.
*
* @param viewer
* the viewer for which the context is created
* @param region
* the region into <code>document</code> for which the
* context is created
* @param offset
* the original offset where content assist was invoked
* @return a template context that can handle template insertion at the
* given location, or <code>null</code>
*/
private TemplateContext createContext(ITextViewer viewer, IRegion region, int offset) {
// pretty much same code as super.createContext except create
// SmartReplaceTemplateContext
TemplateContextType contextType = getContextType(viewer, region);
if (contextType != null) {
IDocument document = viewer.getDocument();
return new ReplaceNameTemplateContext(contextType, document, region.getOffset(), region.getLength(), offset);
}
return null;
}
protected ICompletionProposal createProposal(Template template, TemplateContext context, IRegion region, int relevance) {
return new CustomTemplateProposal(template, context, region, getImage(template), relevance);
}
protected TemplateContextType getContextType(ITextViewer viewer, IRegion region) {
TemplateContextType type = null;
ContextTypeRegistry registry = getTemplateContextRegistry();
if (registry != null)
type = registry.getContextType(fContextTypeId);
return type;
}
protected Image getImage(Template template) {
// just return the same image for now
return HTMLEditorPluginImageHelper.getInstance().getImage(HTMLEditorPluginImages.IMG_OBJ_TAG_TEMPLATE);
}
private ContextTypeRegistry getTemplateContextRegistry() {
return HTMLUIPlugin.getDefault().getTemplateContextRegistry();
}
protected Template[] getTemplates(String contextTypeId) {
Template templates[] = null;
TemplateStore store = getTemplateStore();
if (store != null)
templates = store.getTemplates(contextTypeId);
return templates;
}
private TemplateStore getTemplateStore() {
return HTMLUIPlugin.getDefault().getTemplateStore();
}
public void setContextType(String contextTypeId) {
fContextTypeId = contextTypeId;
}
}