/*
    * Copyright 2008 The Kuali Foundation
    * 
    * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php
    * 
   * 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 org.kuali.ole.sys.spring.datadictionary;
  
  import org.apache.log4j.Logger;
  import org.springframework.beans.factory.support.AbstractBeanDefinition;
  import org.springframework.beans.factory.support.BeanDefinitionBuilder;
  import org.springframework.beans.factory.xml.AbstractBeanDefinitionParser;
  import org.springframework.beans.factory.xml.ParserContext;
  import org.springframework.util.StringUtils;
  import org.w3c.dom.Element;
  import org.w3c.dom.Node;
  import org.w3c.dom.NodeList;
  
  public abstract class KualiBeanDefinitionParserBase extends AbstractBeanDefinitionParser {
  
      private static Logger LOG = Logger.getLogger(KualiBeanDefinitionParserBase.class);
      
      protected void parseEmbeddedPropertyElements(Element element, BeanDefinitionBuilder bean) {
          NodeList children = element.getChildNodes();
          for ( int i = 0; i < children.getLength(); i++ ) {
              Node child = children.item(i);
              if ( child.getLocalName() != null && child.getLocalName().equals("property") ) {
                  Element propertyElement = (Element)child;                
                  String propName = propertyElement.getAttribute("name");
                  String propValue = propertyElement.getAttribute("value");
                  if ( propValue != null ) {
                      bean.addPropertyValue(propName, propValue);
                  } else if ( propertyElement.getAttribute("ref") != null ) {
                      bean.addPropertyReference(propName, propertyElement.getAttribute("ref") );
                  }
              }
          }        
      }
      
      protected void handleAbstractAttribute( Element element, BeanDefinitionBuilder bean) {
          String abstractStr = element.getAttribute("abstract");
          
          if ( StringUtils.hasText(abstractStr) ) {
              bean.setAbstract( Boolean.valueOf(abstractStr) );
          }
      }
      
      /* The below copied from AbstractSingleBeanDefinitionParser and modified to allow for parent beans to be handled. */
      /**
       * Creates a {@link BeanDefinitionBuilder} instance for the
       * {@link #getBeanClass bean Class} and passes it to the
       * {@link #doParse} strategy method.
       * @param element the element that is to be parsed into a single BeanDefinition
       * @param parserContext the object encapsulating the current state of the parsing process
       * @return the BeanDefinition resulting from the parsing of the supplied {@link Element}
       * @throws IllegalStateException if the bean {@link Class} returned from
       * {@link #getBeanClass(org.w3c.dom.Element)} is <code>null</code>
       * @see #doParse
       */
      @SuppressWarnings("unchecked")
      protected final AbstractBeanDefinition parseInternal(Element element, ParserContext parserContext) {
          BeanDefinitionBuilder builder = null;
          
          String parent = element.getAttribute("parent");
          String beanClass = element.getAttribute("class");
          if ( StringUtils.hasText(beanClass) ) {
              try {
                  builder = BeanDefinitionBuilder.rootBeanDefinition(Class.forName(beanClass));
              } catch (Exception ex) {
                  LOG.fatal( "Unable to resolve class given in class element of a " + element.getLocalName() + " element with id " + element.getAttribute("id"), ex );
                  throw new RuntimeException(ex);
              }
          } else  if ( StringUtils.hasText(parent)) {
              builder = BeanDefinitionBuilder.childBeanDefinition(parent);
          } else if ( getBeanClass(element) != null ) {
              builder = BeanDefinitionBuilder.rootBeanDefinition(getBeanClass(element));
          } else {
              builder = BeanDefinitionBuilder.childBeanDefinition(getBaseBeanTypeParent(element)); 
          }
          builder.setSource(parserContext.extractSource(element));
          if (parserContext.isNested()) {
              // Inner bean definition must receive same singleton status as containing bean.
              builder.setSingleton(parserContext.getContainingBeanDefinition().isSingleton());
          }
          if (parserContext.isDefaultLazyInit()) {
              // Default-lazy-init applies to custom bean definitions as well.
              builder.setLazyInit(true);
          }
          doParse(element, parserContext, builder);
          return builder.getBeanDefinition();
     }
 
     /**
      * Parse the supplied {@link Element} and populate the supplied
      * {@link BeanDefinitionBuilder} as required.
      * <p>The default implementation delegates to the <code>doParse</code>
      * version without ParserContext argument.
      * @param element the XML element being parsed
      * @param parserContext the object encapsulating the current state of the parsing process
      * @param builder used to define the <code>BeanDefinition</code>
      * @see #doParse(Element, BeanDefinitionBuilder)
      */
     protected abstract void doParse(Element element, ParserContext parserContext, BeanDefinitionBuilder builder);
 
     protected abstract String getBaseBeanTypeParent( Element element );
     
     protected Class getBeanClass( Element element ) {
         return null;
     }
 }