plugins/org.eclipse.mylyn.docs.intent.client.ui/src/org/eclipse/mylyn/docs/intent/client/ui/editor/IntentEditorDropSupport.java

/*******************************************************************************
 * Copyright (c) 2012 Obeo.

 * 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:
 *     Obeo - initial API and implementation
 *******************************************************************************/
package org.eclipse.mylyn.docs.intent.client.ui.editor;

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

import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.util.EcoreUtil;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.mylyn.docs.intent.collab.common.logger.IIntentLogger.LogType;
import org.eclipse.mylyn.docs.intent.collab.common.logger.IntentLogger;
import org.eclipse.mylyn.docs.intent.collab.common.query.CompilationStatusQuery;
import org.eclipse.mylyn.docs.intent.collab.handlers.adapters.RepositoryAdapter;
import org.eclipse.mylyn.docs.intent.core.compiler.CompilationStatus;
import org.eclipse.mylyn.docs.intent.core.compiler.ModelElementChangeStatus;
import org.eclipse.mylyn.docs.intent.core.modelingunit.ModelingUnit;
import org.eclipse.mylyn.docs.intent.modelingunit.update.ModelingUnitUpdater;
import org.eclipse.swt.dnd.DropTargetAdapter;
import org.eclipse.swt.dnd.DropTargetEvent;

/**
 * Implementation of the drop support in intent editor.
 * 
 * @author <a href="mailto:william.piers@obeo.fr">William Piers</a>
 */
public class IntentEditorDropSupport extends DropTargetAdapter {

	private IntentEditor editor;

	private IntentEditorDocument document;

	/**
	 * Constructor.
	 * 
	 * @param editor
	 *            the intent editor
	 */
	public IntentEditorDropSupport(IntentEditor editor) {
		this.editor = editor;
		this.document = (IntentEditorDocument)editor.getDocumentProvider().getDocument(
				editor.getEditorInput());
	}

	/**
	 * {@inheritDoc}
	 * 
	 * @see org.eclipse.swt.dnd.DropTargetAdapter#drop(org.eclipse.swt.dnd.DropTargetEvent)
	 */
	public void drop(DropTargetEvent event) {
		if (event.data instanceof IStructuredSelection) {
			// TODO support resource drop ?
			List<EObject> droppedEObjects = new ArrayList<EObject>();
			for (Iterator<?> iterator = ((IStructuredSelection)event.data).iterator(); iterator.hasNext();) {
				Object data = iterator.next();
				if (data instanceof EObject) {
					droppedEObjects.add((EObject)data);
				}
			}

			EObject intentElement = document.getElementAtOffset(editor.getProjectionViewer().getTextWidget()
					.getCaretOffset());

			// TODO accurate drop, currently parent modeling unit lookup
			// TODO we should be able to create a new modeling unit
			EObject parent = intentElement.eContainer();
			while (parent != null && !(parent instanceof ModelingUnit)) {
				parent = parent.eContainer();
			}
			if (parent != null) {
				updateModelingUnit((ModelingUnit)parent, droppedEObjects);
			} else {
				// TODO manage modeling units creation
				IntentLogger.getInstance().log(LogType.ERROR, "Only modeling units support drops.");
			}

		}
	}

	/**
	 * Updates the given modeling unit with the addition of the given objects.
	 * 
	 * @param modelingUnit
	 *            the modeling unit to update
	 * @param elements
	 *            the elements to add or update
	 */
	private void updateModelingUnit(final ModelingUnit modelingUnit, List<EObject> elements) {
		// computes the elements uris
		List<String> uriFragments = new ArrayList<String>(elements.size());
		for (EObject eObject : elements) {
			uriFragments.add(EcoreUtil.getURI(eObject).toString());
		}

		IntentDocumentProvider documentProvider = (IntentDocumentProvider)editor.getDocumentProvider();
		final RepositoryAdapter repositoryAdapter = documentProvider.getListenedElementsHandler()
				.getRepositoryAdapter();
		ModelingUnitUpdater updater = new ModelingUnitUpdater(repositoryAdapter);

		boolean astChanged = false;
		CompilationStatusQuery query = new CompilationStatusQuery(repositoryAdapter);
		for (CompilationStatus compilationStatus : query.getOrCreateCompilationStatusManager()
				.getCompilationStatusList()) {
			if (compilationStatus instanceof ModelElementChangeStatus) {
				ModelElementChangeStatus status = (ModelElementChangeStatus)compilationStatus;
				if (uriFragments.contains(status.getWorkingCopyElementURIFragment())) {
					updater.fixSynchronizationStatus(modelingUnit, status);
					astChanged = true;
				}
			}
		}

		// finally, reload the document if necessary
		if (astChanged) {
			document.reloadFromAST();
		}
	}
}