/**
 * Copyright (c) 2009 Anyware Technologies 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:
 *     Anyware Technologies - initial API and implementation
 *
 * $Id: ValidatingEContentAdapter.java,v 1.11 2009/09/22 14:54:31 bcabe Exp $
 */
package org.eclipse.pde.emfforms.internal.validation;

import java.util.*;
import org.eclipse.core.databinding.DataBindingContext;
import org.eclipse.emf.common.notify.Notification;
import org.eclipse.emf.common.util.Diagnostic;
import org.eclipse.emf.common.util.DiagnosticChain;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.resource.Resource;
import org.eclipse.emf.ecore.util.Diagnostician;
import org.eclipse.emf.ecore.util.EContentAdapter;
import org.eclipse.emf.edit.provider.IItemLabelProvider;
import org.eclipse.emf.transaction.NotificationFilter;
import org.eclipse.pde.emfforms.editor.EmfFormEditor;
import org.eclipse.pde.emfforms.editor.ValidatingService;
import org.eclipse.pde.emfforms.internal.Activator;
import org.eclipse.ui.forms.IMessageManager;
import org.eclipse.ui.forms.editor.IFormPage;
import org.osgi.framework.*;

public class ValidatingEContentAdapter extends EContentAdapter {
	private EmfFormEditor<?> _formEditor;
	private DataBindingContext _dataBindingContext;
	private Diagnostician _diagnostician;

	private ValidatingService validatingService;

	public ValidatingEContentAdapter(EmfFormEditor<?> formEditor) {
		_formEditor = formEditor;
		_dataBindingContext = formEditor.getDataBindingContext();

		// if SCR is not present, we want to register the Eclipse 3.4 validator manually ...
		forceValidatingService34Registration();

		// Subclass the default Diagnostician to customize the String
		// representation of each validated EObject
		_diagnostician = new Diagnostician() {
			@Override
			public String getObjectLabel(EObject eObject) {
				if (!eObject.eIsProxy()) {
					IItemLabelProvider itemLabelProvider = (IItemLabelProvider) _formEditor.getAdapterFactory().adapt(eObject, IItemLabelProvider.class);
					if (itemLabelProvider != null) {
						return itemLabelProvider.getText(eObject);
					}
				}

				return super.getObjectLabel(eObject);
			}

			protected boolean doValidateContents(EObject eObject, DiagnosticChain diagnostics, Map<Object, Object> context) {

				Resource eContainerResource = eObject.eResource();
				List<EObject> eContents = eObject.eContents();
				if (!eContents.isEmpty()) {
					boolean result = true;
					for (Iterator<EObject> i = eContents.iterator(); i.hasNext() && (result || diagnostics != null);) {
						EObject child = i.next();
						// in case of cross resource containment, 
						// avoid to validate a child which are not in the container resource
						Resource eChildResource = child.eResource();
						if (eContainerResource != null && eChildResource == eContainerResource) {
							result &= validate(child, diagnostics, context);
						}
					}
					return result;
				}
				return true;
			}
		};
	}

	private void forceValidatingService34Registration() {
		if (getValidatorService() == null) {
			BundleContext context = Activator.getDefault().getBundle().getBundleContext();
			Properties serviceProperties = new Properties();
			serviceProperties.put(Constants.SERVICE_RANKING, 10);
			context.registerService(ValidatingService.class.getName(), new ValidatingService34(), serviceProperties);
		}
	}

	@Override
	public void notifyChanged(Notification notification) {
		super.notifyChanged(notification);
		if (!NotificationFilter.READ.matches(notification)) {
			validate();
		}
	}

	public void validate() {
		IFormPage activePageInstance = _formEditor.getActivePageInstance();
		if (_formEditor.getActivePageInstance() == null) {
			return;
		}

		IMessageManager messageManager = activePageInstance.getManagedForm().getMessageManager();
		messageManager.removeAllMessages();
		messageManager.setAutoUpdate(false);

		Diagnostic diagnostics = validate(_formEditor.getCurrentEObject());

		for (Diagnostic diagnostic : diagnostics.getChildren()) {
			getValidatorService().analyzeDiagnostic(_dataBindingContext, diagnostic, messageManager);
		}

		messageManager.update();
	}

	public Diagnostic validate(EObject obj) {
		return _diagnostician.validate(obj);
	}

	private ValidatingService getValidatorService() {
		BundleContext context = Activator.getDefault().getBundle().getBundleContext();
		if (validatingService == null) {
			ServiceReference validatingServiceRef = context.getServiceReference(ValidatingService.class.getName());
			if (validatingServiceRef != null)
				validatingService = (ValidatingService) context.getService(validatingServiceRef);
		}
		return validatingService;
	}

}