package org.kuali.spring.util;

 import java.util.ArrayList;

 import java.util.List;

 import org.kuali.spring.util.event.BeanVisitEvent;

 import org.kuali.spring.util.event.PropertyValueVisitEvent;

 import org.kuali.spring.util.event.ValueResolutionEvent;

 import org.kuali.spring.util.event.VisitListener;

 import org.slf4j.Logger;

 import org.slf4j.LoggerFactory;

 import org.springframework.beans.MutablePropertyValues;

 import org.springframework.beans.PropertyValue;

 import org.springframework.beans.factory.config.BeanDefinition;

 import org.springframework.beans.factory.config.BeanDefinitionVisitor;

 import org.springframework.util.ObjectUtils;

 import org.springframework.util.StringValueResolver;

 public class EnhancedBeanDefinitionVisitor extends BeanDefinitionVisitor {

     final Logger logger = LoggerFactory.getLogger(EnhancedBeanDefinitionVisitor.class);

     List<VisitListener> listeners = new ArrayList<VisitListener>();

     StringValueResolver valueResolver;

     public EnhancedBeanDefinitionVisitor() {

         this(null);

     }

     public EnhancedBeanDefinitionVisitor(StringValueResolver valueResolver) {

         super();

         this.valueResolver = valueResolver;

     }

     @Override

     protected String resolveStringValue(String strVal) {

         if (this.valueResolver == null) {

             throw new IllegalStateException("No StringValueResolver specified");

         }

         String resolvedValue = this.valueResolver.resolveStringValue(strVal);

         // Return original String if not modified.

         return (strVal.equals(resolvedValue) ? strVal : resolvedValue);

     }

     public void addListener(VisitListener listener) {

         listeners.add(listener);

     }

     @Override

     protected Object resolveValue(Object value) {

         Object newValue = super.resolveValue(value);

         valueResolved(value, newValue);

         return newValue;

     }

     @Override

     public void visitBeanDefinition(BeanDefinition beanDefinition) {

         beforeVisit(beanDefinition);

         super.visitBeanDefinition(beanDefinition);

         afterVisit(beanDefinition);

     }

     @Override

     protected void visitPropertyValues(MutablePropertyValues pvs) {

         PropertyValue[] pvArray = pvs.getPropertyValues();

         for (PropertyValue pv : pvArray) {

             visitPropertyValue(pvs, pv);

         }

     }

     protected void visitPropertyValue(MutablePropertyValues pvs, PropertyValue pv) {

         beforeVisit(pvs, pv);

         Object oldVal = pv.getValue();

         Object newVal = resolveValue(pv.getValue());

         if (!ObjectUtils.nullSafeEquals(newVal, oldVal)) {

             pvs.add(pv.getName(), newVal);

         }

         afterVisit(pvs, pv, oldVal, newVal);

     }

     protected void beforeVisit(MutablePropertyValues pvs, PropertyValue pv) {

         PropertyValueVisitEvent event = new PropertyValueVisitEvent(pvs, pv);

         for (VisitListener listener : listeners) {

             listener.beforeVisit(event);

         }

     }

     protected void afterVisit(MutablePropertyValues pvs, PropertyValue pv, Object oldVal, Object newVal) {

         PropertyValueVisitEvent event = new PropertyValueVisitEvent(pvs, pv, oldVal, newVal);

         for (VisitListener listener : listeners) {

             listener.afterVisit(event);

         }

     }

     protected void beforeVisit(BeanDefinition beanDefinition) {

         BeanVisitEvent event = new BeanVisitEvent(beanDefinition);

         for (VisitListener listener : listeners) {

             listener.beforeVisit(event);

         }

     }

     protected void afterVisit(BeanDefinition beanDefinition) {

         BeanVisitEvent event = new BeanVisitEvent(beanDefinition);

         for (VisitListener listener : listeners) {

             listener.afterVisit(event);

         }

     }

     protected void valueResolved(Object oldValue, Object newValue) {

         ValueResolutionEvent event = new ValueResolutionEvent(oldValue, newValue);

         for (VisitListener listener : listeners) {

             listener.valueResolved(event);

         }

     }

     public List<VisitListener> getListeners() {

         return listeners;

     }

     public void setListeners(List<VisitListener> listeners) {

         this.listeners = listeners;

     }

     public StringValueResolver getValueResolver() {

         return valueResolver;

     }

     public void setValueResolver(StringValueResolver valueResolver) {

         this.valueResolver = valueResolver;

     }

 }