/*
    * EL4J, the Extension Library for the J2EE, adds incremental enhancements to
    * the spring framework, http://el4j.sf.net
    * Copyright (C) 2005 by ELCA Informatique SA, Av. de la Harpe 22-24,
    * 1000 Lausanne, Switzerland, http://www.elca.ch
    *
    * EL4J is published under the GNU Lesser General Public License (LGPL)
    * Version 2.1. See http://www.gnu.org/licenses/
    *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
   * GNU Lesser General Public License for more details.
   *
   * For alternative licensing, please contact info@elca.ch
   */
  package ch.elca.el4j.services.gui.swing.cookswing.binding;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.jdesktop.beansbinding.AutoBinding;
  import org.jdesktop.beansbinding.AutoBinding.UpdateStrategy;
  import org.jdesktop.beansbinding.Property;
  
  import org.w3c.dom.Element;
  
  import com.silvermindsoftware.hitch.binding.PropertyUtil;
  
  import cookxml.core.DecodeEngine;
  import cookxml.core.exception.CookXmlException;
  import cookxml.core.interfaces.Creator;
  
  /**
   * This class provides basic functionality for cookXML binding creators.
   *
   * @svnLink $Revision: 3873 $;$Date: 2009-08-04 13:59:45 +0200 (Di, 04. Aug 2009) $;$Author: swismer $;$URL: https://el4j.svn.sourceforge.net/svnroot/el4j/branches/el4j_3_1/el4j/framework/modules/swing/src/main/java/ch/elca/el4j/services/gui/swing/cookswing/binding/AbstractBindingCreator.java $
   *
   * @author Stefan Wismer (SWI)
   */
  public abstract class AbstractBindingCreator implements Creator {
  	// some common attributes
  	private static final String SOURCE = "src";
  	protected static final String PROPERTY = "property";
  	protected static final String VALIDATION = "validation";
  	protected static final String UPDATE_STRATEGY = "updateStrategy";
  	
  	/**
  	 * The logger.
  	 */
  	private static final Logger s_logger = LoggerFactory
  		.getLogger(AbstractBindingCreator.class);
  	
  	/**
  	 * @param elm    the current XML element
  	 * @return       the updateStrategy attribute
  	 */
  	protected UpdateStrategy getUpdateStrategy(Element elm) {
  		UpdateStrategy updateStrategy = UpdateStrategy.READ;
  		String updateStrategyString = elm.getAttribute(UPDATE_STRATEGY);
  		if (updateStrategyString.equals("read once")) {
  			updateStrategy = UpdateStrategy.READ_ONCE;
  		} else if (updateStrategyString.equals("read write")) {
  			updateStrategy = UpdateStrategy.READ_WRITE;
  		}
  		return updateStrategy;
  	}
  	
  	/**
  	 * @param decodeEngine    the cookXML decodeEngine
  	 * @param elm             the current XML element
  	 * @return                the source object to bind
  	 */
  	@SuppressWarnings("unchecked")
  	protected Object getSource(DecodeEngine decodeEngine, Element elm) {
  		Object obj = null;
  		String src = elm.getAttribute(SOURCE);
  		if (!src.equals("")) {
  			if (src.contains(".")) {
  				Property prop = PropertyUtil.create(
  					src.substring(src.indexOf(".") + 1));
  				obj = prop.getValue(decodeEngine.getVariable(
  					src.substring(0, src.indexOf("."))));
  			} else {
  				obj = decodeEngine.getVariable(elm.getAttribute(SOURCE));
  			}
  		} else {
  			s_logger.error("Error processing XML element " + elm.getNodeName()
  				+ ". Mandatory attribute '" + SOURCE + "' not found.");
  		}
  		return obj;
  	}
  	
  	/**
  	 * @param elm    the current XML element
  	 * @return       <code>true</code> if values should be validated
  	 */
  	protected boolean getValidate(Element elm) {
  		boolean validate = Boolean.parseBoolean(elm.getAttribute(VALIDATION));
  		if (!elm.getAttribute(VALIDATION).equals("")) {
 			validate = true;
 		}
 		return validate;
 	}
 	
 	/**
 	 * Adds binding to the class associated with this XML GUI description.
 	 * @param decodeEngine    the cookXML decodeEngine
 	 * @param binding         the beans binding to add
 	 */
 	@SuppressWarnings("unchecked")
 	protected void addBinding(DecodeEngine decodeEngine, AutoBinding binding) {
 		Object form = decodeEngine.getVariable("this");
 		if (Bindable.class.isAssignableFrom(form.getClass())) {
 			Bindable bindableForm = (Bindable) form;
 			
 			bindableForm.getBinder().addManualBinding(binding);
 		} else {
 			s_logger.warn("No class to bind found. " + form
 				+ " does not implement interface Bindable");
 		}
 	}
 	
 	/** {@inheritDoc} */
 	public Object editFinished(String parentNS, String parentTag, Element elm,
 		Object parentObj, Object obj, DecodeEngine decodeEngine)
 		throws CookXmlException {
 
 		return obj;
 	}
 }