GeneratorModelLinkingService.java

/*******************************************************************************
 * Copyright (c) 2010-2012, Zoltan Ujhelyi, Istvan Rath and Daniel Varro
 * 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:
 *   Zoltan Ujhelyi - initial API and implementation
 *******************************************************************************/
package org.eclipse.incquery.tooling.generator.model.scoping;

import java.util.Collections;
import java.util.List;

import org.apache.log4j.Logger;
import org.eclipse.emf.codegen.ecore.genmodel.GenModel;
import org.eclipse.emf.common.util.URI;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.EReference;
import org.eclipse.emf.ecore.resource.Resource;
import org.eclipse.emf.ecore.resource.ResourceSet;
import org.eclipse.incquery.tooling.generator.model.generatorModel.GeneratorModelPackage;
import org.eclipse.incquery.tooling.generator.model.generatorModel.GeneratorModelReference;
import org.eclipse.xtext.conversion.IValueConverterService;
import org.eclipse.xtext.conversion.ValueConverterException;
import org.eclipse.xtext.linking.impl.DefaultLinkingService;
import org.eclipse.xtext.nodemodel.ILeafNode;
import org.eclipse.xtext.nodemodel.INode;

import com.google.inject.Inject;

public class GeneratorModelLinkingService extends DefaultLinkingService {
    private static final Logger LOG = Logger.getLogger(GeneratorModelLinkingService.class);

    @Inject
    private IValueConverterService valueConverterService;

    @Override
    public List<EObject> getLinkedObjects(EObject context, EReference ref, INode node) {
        if (ref == GeneratorModelPackage.eINSTANCE.getGeneratorModelReference_Genmodel()
                && context instanceof GeneratorModelReference && node instanceof ILeafNode) {
            return getGenModel((GeneratorModelReference) context, (ILeafNode) node);
        }
        return super.getLinkedObjects(context, ref, node);
    }

    private List<EObject> getGenModel(GeneratorModelReference context, ILeafNode text) {
        String nsUri = getMetamodelNsURI(text);
        if (nsUri == null) {
            return Collections.emptyList();
        }
        GenModel pack = loadGenmodel(nsUri, context.eResource().getResourceSet());
        if (pack != null) {
            return Collections.<EObject> singletonList(pack);
        }
        return Collections.emptyList();
    }

    private String getMetamodelNsURI(ILeafNode text) {
        try {
            return (String) valueConverterService.toValue(text.getText(),
                    getLinkingHelper().getRuleNameFrom(text.getGrammarElement()), text);
        } catch (ValueConverterException e) {
            LOG.debug("Exception on leaf '" + text.getText() + "'", e);
            return null;
        }
    }

    private GenModel loadGenmodel(String resourceOrNsURI, ResourceSet resourceSet) {
        URI uri = null;
        try {
            uri = URI.createURI(resourceOrNsURI);
            if (uri.fragment() == null) {
                Resource resource = resourceSet.getResource(uri, true);
                return (GenModel) resource.getContents().get(0);
            }
            return (GenModel) resourceSet.getEObject(uri, true);
        } catch (IllegalArgumentException ex) {
            LOG.trace("Invalid package URI: '" + resourceOrNsURI + "'", ex);
            return null;
        } catch (RuntimeException ex) {
            if (uri != null && uri.isPlatformResource()) {
                String platformString = uri.toPlatformString(true);
                URI platformPluginURI = URI.createPlatformPluginURI(platformString, true);
                return loadGenmodel(platformPluginURI.toString(), resourceSet);
            }
            LOG.trace("Cannot load package with URI '" + resourceOrNsURI + "'", ex);
            return null;
        }
    }
}