source: default/trunk/de.ugoe.cs.swe.bnftools.ebnf.ui/src/de/ugoe/cs/swe/bnftools/utils/Utils.java

package de.ugoe.cs.swe.bnftools.utils;

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

import org.eclipse.emf.ecore.EObject;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.ITextSelection;
import org.eclipse.xtext.builder.builderState.impl.ReferenceDescriptionImpl;
import org.eclipse.xtext.parsetree.CompositeNode;
import org.eclipse.xtext.parsetree.NodeAdapter;
import org.eclipse.xtext.parsetree.NodeUtil;
import org.eclipse.xtext.resource.IEObjectDescription;
import org.eclipse.xtext.resource.IReferenceDescription;
import org.eclipse.xtext.resource.IResourceDescription;
import org.eclipse.xtext.resource.IResourceDescriptions;
import org.eclipse.xtext.ui.editor.XtextEditor;
import org.eclipse.xtext.ui.editor.model.IXtextDocument;

import com.google.common.base.Predicate;
import com.google.common.collect.Iterables;

import de.ugoe.cs.swe.bnftools.ebnf.BnfEntry;
import de.ugoe.cs.swe.bnftools.ebnf.DeltaEntry;
import de.ugoe.cs.swe.bnftools.ebnf.EtsiBnf;
import de.ugoe.cs.swe.bnftools.ebnf.MergeEntry;
import de.ugoe.cs.swe.bnftools.ebnf.Rule;

public class Utils {
        
        static public NodeAdapter findNodeFromSelection(
                        final XtextEditor xtextEditor, ITextSelection mySelection) {
                if ((xtextEditor == null) || (xtextEditor.getDocument() == null))
                        return null;
                EtsiBnf root = (EtsiBnf) xtextEditor.getDocument().readOnly(
                                new RootEObjectFinder());
                
                NodeAdapter resultNode = null;
                if (root.getBnfEntry() != null) {
                        System.out.println("bnf grammar!");
                        for (int i=0; i < root.getBnfEntry().size(); i++) {
                                BnfEntry entry = root.getBnfEntry().get(i);
                                if (entry.getRule() != null) {
                                        resultNode = findNodeInRule(entry.getRule(), mySelection);
                                        if (resultNode != null)
                                                return resultNode;
                                }
                        }
                } else if (root.getDeltaEntry() != null) {
                        for (int i=0; i < root.getDeltaEntry().size(); i++) {
                                DeltaEntry entry = root.getDeltaEntry().get(i);
                                if (entry.getRule() != null) {
                                        resultNode = findNodeInRule(entry.getRule(), mySelection);
                                        if (resultNode != null)
                                                return resultNode;
                                }
                        }
                } else if (root.getMergeEntry() != null) {
                        for (int i=0; i < root.getMergeEntry().size(); i++) {
                                MergeEntry entry = root.getMergeEntry().get(i);
                                if (entry.getMergeRule() != null) {
                                        // TODO: doesn't work here...
//                                      resultNode = findNodeInRule(entry.getgetRule(), mySelection);
//                                      if (resultNode != null)
//                                              return resultNode;
                                }
                        }
                }
                
                return resultNode;
        }
        
        // --------------------------------------------------------------------------------

        static private NodeAdapter findNodeInRule(Rule rule, ITextSelection mySelection) {
                NodeAdapter node = NodeUtil.getNodeAdapter(rule);
                if ((node.getParserNode().getOffset() <= mySelection.getOffset())
                                && (mySelection.getOffset() <= node.getParserNode()
                                                .getOffset()
                                                + node.getParserNode().getLength())) {
                        return node;
                }
                
                return null;
        }
        
        // --------------------------------------------------------------------------------

        static public List<CompositeNode> findReferenceDescriptions(
                        final IEObjectDescription eObjectDescription, IResourceDescriptions resourceDescriptions, XtextEditor editor) {
//TODO: resolved nur innerhalb derselben datei!
                List<CompositeNode> references = new ArrayList<CompositeNode>();

                for (IResourceDescription resourceDescription : resourceDescriptions
                                .getAllResourceDescriptions()) {
                        Iterable<IReferenceDescription> matchingReferenceDescriptors = Iterables
                                        .filter(resourceDescription.getReferenceDescriptions(),
                                                        new Predicate<IReferenceDescription>() {
                                                                public boolean apply(IReferenceDescription input) {
                                                                        return eObjectDescription
                                                                                        .getEObjectURI()
                                                                                        .equals(input.getTargetEObjectUri());
                                                                }
                                                        });
                        for (IReferenceDescription matchingReferenceDescription : matchingReferenceDescriptors) {
//TODO: dieser check ignoriert links zu anderen dateien wg. exception
                                if ((matchingReferenceDescription instanceof org.eclipse.xtext.resource.impl.DefaultReferenceDescription) || (matchingReferenceDescription instanceof ReferenceDescriptionImpl)){
                                        URIFragmentResolver uriFragmentResolver = new URIFragmentResolver(matchingReferenceDescription
                                                        .getSourceEObjectUri().fragment());
                                        CompositeNode node = editor.getDocument().readOnly(uriFragmentResolver);
                                        if (node != null)
                                                references.add(node);
                                }
                        }
                }
                return references;
        }

        // --------------------------------------------------------------------------------

        static public List<CompositeNode> findReferences(EObject o, IResourceDescriptions resourceDescriptions, XtextEditor editor) {
                final IEObjectDescription eObjectDescription = editor.getDocument()
                .readOnly(new EObjectResolver(o, resourceDescriptions));

                List<CompositeNode> referenceDescriptions = Utils.findReferenceDescriptions(eObjectDescription, resourceDescriptions, editor);
                return referenceDescriptions;
        }
        
        // --------------------------------------------------------------------------------

        static public int stepBackNewlines(IXtextDocument document, int offset) {
                if (offset <= 0)
                        return 0;
                
                try {
                        int tempOffset = offset;
                        String str = document.get(tempOffset-1, 1);
                        while (str.equals("\n") || str.equals("\r") || str.equals(" ")) {
                                tempOffset -= 1;
                                str = document.get(tempOffset-1, 1);
                        }
                        return offset - tempOffset;
                } catch (BadLocationException e) {
                        e.printStackTrace();
                }
                return 0;
        }

}