/*
 *                                                                            
 *  Copyright (c) 2011, 2016 - Loetz GmbH&Co.KG (69115 Heidelberg, Germany) 
 *                                                                            
 *  All rights reserved. This program and the accompanying materials           
 *  are made available under the terms of the Eclipse Public License 2.0        
 *  which accompanies this distribution, and is available at                  
 *  https://www.eclipse.org/legal/epl-2.0/                                 
 *                                 
 *  SPDX-License-Identifier: EPL-2.0                                 
 *                                                                            
 *  Contributors:                                                      
 * 	   Florian Pirchner - Initial implementation
 *     Loetz GmbH&Co.KG                               
 * 
 */
package org.eclipse.osbp.vaadin.emf.data.fields;

import java.util.Collection;

import org.eclipse.emf.common.notify.AdapterFactory;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.EStructuralFeature;
import org.eclipse.emf.edit.provider.IItemLabelProvider;

import com.vaadin.data.Item;
import com.vaadin.data.util.ObjectProperty;
import com.vaadin.ui.ComboBox;
import com.vaadin.ui.Component;
import com.vaadin.ui.CustomField;

// TODO: Auto-generated Javadoc
/**
 * A combobox to select referenced EObjects.
 */
@SuppressWarnings("serial")
public class EObjectComboBox extends CustomField<EObject> {

	/** The adapter factory. */
	private final AdapterFactory adapterFactory;

	/** The combobox. */
	private ComboBox combobox;

	/** The property. */
	private ObjectProperty<EObject> property;

	/**
	 * Instantiates a new e object combo box.
	 *
	 * @param adapterFactory
	 *            the adapter factory
	 */
	public EObjectComboBox(AdapterFactory adapterFactory) {
		this.adapterFactory = adapterFactory;

		// eager init
		initContent();
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see com.vaadin.ui.CustomField#initContent()
	 */
	@Override
	protected Component initContent() {
		if (combobox != null) {
			return combobox;
		}

		combobox = new ComboBox();
		combobox.setWidth("100%");
		combobox.setItemCaptionPropertyId("name");

		combobox.addContainerProperty("name", String.class, "");

		property = new ObjectProperty<EObject>(null, EObject.class);
		combobox.setPropertyDataSource(property);

		property.addValueChangeListener(e -> {
			super.setValue((EObject) e.getProperty().getValue());
		});

		return combobox;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see com.vaadin.ui.AbstractField#getType()
	 */
	@Override
	public Class<EObject> getType() {
		return EObject.class;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see com.vaadin.ui.AbstractField#setInternalValue(java.lang.Object)
	 */
	@Override
	protected void setInternalValue(EObject newValue) {
		super.setInternalValue(newValue);

		if (property != null) {
			property.setValue(newValue);
		}
	}

	/**
	 * Gets the collection.
	 *
	 * @return the collection
	 */
	@SuppressWarnings("unchecked")
	public Collection<EObject> getCollection() {
		return (Collection<EObject>) combobox.getItemIds();
	}

	/**
	 * Sets the collection.
	 *
	 * @param eObjects
	 *            the new collection
	 */
	@SuppressWarnings("unchecked")
	public void setCollection(Collection<? extends EObject> eObjects) {
		initContent();

		combobox.removeAllItems();

		for (EObject eObject : eObjects) {
			if (eObject == null) {
				continue;
			}
			IItemLabelProvider provider = (IItemLabelProvider) adapterFactory
					.adapt(eObject, IItemLabelProvider.class);
			if (provider != null) {
				Item item = combobox.addItem(eObject);
				item.getItemProperty("name")
						.setValue(provider.getText(eObject));
			} else if (eObject.eClass().getEStructuralFeature("name") != null) {
				Item item = combobox.addItem(eObject);
				item.getItemProperty("name").setValue(
						eObject.eGet(eObject.eClass().getEStructuralFeature(
								"name")));
			}
		}
	}
}