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/**
 * Copyright (C) 2015 Asterios Raptis
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *         http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package de.alpharogroup.model;

/**
 * A PropertyModel is used to dynamically access a model using a "property expression".  For
 * example, take the following bean:
 *
 *  * public class Person
 * {
 * 	private String name;
 *
 * 	public String getName()
 * 	{
 * 		return name;
 * 	}
 *
 * 	public void setName(String name)
 * 	{
 * 		this.name = name;
 * 	}
 * }
 * 
 *
 * We could construct a label that dynamically fetches the name property of the given person object
 * like this:
 *
 *  *     Person person = getSomePerson();
 *     ...
 *     add(new Label("myLabel", new PropertyModel(person, "name"));
 * 
 *
 * Where 'myLabel' is the name of the component, and 'name' is the property expression to get the
 * name property. 
  In the same fashion, we can create form components that work
 * dynamically on the given model object. For instance, we could create a text field that updates
 * the name property of a person like this:
 *
 *  *     add(new TextField("myTextField", new PropertyModel(person, "name"));
 * 
 *
 * 
  Note that the property resolver by default provides access to private
 * members and methods. If guaranteeing encapsulation of the target objects is a big concern, you
 * should consider using an alternative implementation. 
 *
 * @see LoadableDetachableModel
 *
 * @author Chris Turner
 * @author Eelco Hillenius
 * @author Jonathan Locke
 *
 * @param 
 *            The Model object type
 */
public class PropertyModel extends AbstractPropertyModel
{

	/** The Constant serialVersionUID. */
	private static final long serialVersionUID = 1L;

	/**
	 * Type-infering factory method.
	 *
	 * @param 
	 *            the generic type
	 * @param parent
	 *            object that contains the property
	 * @param property
	 *            property path
	 * @return {@link PropertyModel} instance
	 */
	public static  PropertyModel of(final Object parent, final String property)
	{
		return new PropertyModel<>(parent, property);
	}

	/** Property expression for property access. */
	private final String expression;

	/**
	 * Construct with a wrapped (IModel) or unwrapped (non-IModel) object and a property expression
	 * that works on the given model.
	 *
	 * @param modelObject
	 *            The model object, which may or may not implement IModel
	 * @param expression
	 *            Property expression for property access
	 */
	public PropertyModel(final Object modelObject, final String expression)
	{
		super(modelObject);
		this.expression = expression;
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	protected String propertyExpression()
	{
		return expression;
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public String toString()
	{
		final StringBuilder sb = new StringBuilder(super.toString());
		sb.append(":expression=[").append(expression).append("]");
		return sb.toString();
	}

}