/**
    * Copyright 2005-2013 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.rice.krad.datadictionary.parse;
  
  import org.apache.commons.lang.StringUtils;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.springframework.beans.factory.config.BeanDefinition;
  import org.springframework.beans.factory.config.BeanDefinitionHolder;
  import org.springframework.beans.factory.config.RuntimeBeanReference;
  import org.springframework.beans.factory.support.BeanDefinitionBuilder;
  import org.springframework.beans.factory.support.ManagedList;
  import org.springframework.beans.factory.support.ManagedMap;
  import org.springframework.beans.factory.support.ManagedSet;
  import org.springframework.beans.factory.xml.AbstractSingleBeanDefinitionParser;
  import org.springframework.beans.factory.xml.BeanDefinitionParserDelegate;
  import org.springframework.beans.factory.xml.ParserContext;
  import org.springframework.util.xml.DomUtils;
  import org.w3c.dom.Document;
  import org.w3c.dom.Element;
  import org.w3c.dom.NamedNodeMap;
  import org.w3c.dom.Node;
  
  import java.util.ArrayList;
  import java.util.Map;
  
  /**
   * Parser for parsing xml bean's created using the custom schema into normal spring bean format.
   *
   * @author Kuali Rice Team (rice.collab@kuali.org)
   */
  public class CustomSchemaParser extends AbstractSingleBeanDefinitionParser {
      private static final Log LOG = LogFactory.getLog(CustomSchemaParser.class);
  
      private static int beanNumber = 0;
  
      /**
       * Retrieves the class of the bean defined by the xml element.
       *
       * @param bean - The xml element for the bean being parsed.
       * @return The class associated with the provided tag
       */
      protected Class getBeanClass(Element bean) {
          Map<String, BeanTagInfo> beanType = null;
  
          // Attempt to load the list of tags
          try {
              beanType = CustomTagAnnotations.getBeanTags();
          } catch (Exception e) {
              LOG.error("Error retrieving bean tag information", e);
          }
  
          Class<?> beanTag = null;
          try {
              // Retrieve the connected class in the tag map using the xml tag's name.
  
              beanTag = beanType.get(bean.getLocalName()).getBeanClass();
          } catch (Exception e) {
              LOG.error("Error in retrieved bean tag information", e);
          }
  
          return beanTag;
      }
  
      /**
       * Parses the xml bean into a standard bean definition format and fills the information in the passed in definition
       * builder
       *
       * @param element - The xml bean being parsed.
       * @param parserContext - Provided information and functionality regarding current bean set.
       * @param bean - A definition builder used to build a new spring bean from the information it is filled with.
       */
      @Override
      protected void doParse(Element element, ParserContext parserContext, BeanDefinitionBuilder bean) {
          // Retrieve custom schema information build from the annotations
          Map<String, Map<String, BeanTagAttributeInfo>> attributeProperties =
                  CustomTagAnnotations.getAttributeProperties();
          Map<String, BeanTagAttributeInfo> entries = attributeProperties.get(element.getLocalName());
  
          // Log error if there are no attributes found for the bean tag
          if (entries == null) {
              LOG.error("Bean Tag not found " + element.getLocalName());
          }
  
          // Retrieve the information for the new bean tag and fill in the default parent if needed
          BeanTagInfo tagInfo = CustomTagAnnotations.getBeanTags().get(element.getLocalName());
         if (tagInfo.getParent().compareTo("none") != 0) {
             bean.setParentName(tagInfo.getParent());
         }
 
         // Create the map for the attributes found in the tag and process them in to the definition builder.
         NamedNodeMap attributes = element.getAttributes();
         for (int i = 0; i < attributes.getLength(); i++) {
             processSingleValue(attributes.item(i).getNodeName(), attributes.item(i).getNodeValue(), entries, bean);
         }
 
         ArrayList<Element> children = (ArrayList<Element>) DomUtils.getChildElements(element);
 
         // Process the children found in the xml tag
         for (int i = 0; i < children.size(); i++) {
             String tag = children.get(i).getLocalName();
             BeanTagAttributeInfo info = entries.get(tag);
 
             String propertyName;
             BeanTagAttribute.AttributeType type;
 
             if(children.get(i).getTagName().equals("spring:property")){
                 BeanDefinitionParserDelegate delegate = parserContext.getDelegate();
                 delegate.parsePropertyElement(children.get(i), bean.getBeanDefinition());
                 continue;
             }
 
             // Sets the property name to be used when adding the property value
             if (info == null) {
                 // If the tag is not in the schema map let spring handle the value by forwarding the tag as the
                 // propertyName
                 propertyName = tag;
                 type = findBeanType(children.get(i));
 
             } else {
                 // If the tag is found in the schema map use the connected name stored in the attribute information
                 propertyName = info.getName();
                 type = info.getType();
             }
             // Process the information stored in the child bean
             ArrayList<Element> grandChildren = (ArrayList<Element>) DomUtils.getChildElements(children.get(i));
 
             if (type == BeanTagAttribute.AttributeType.SINGLEBEAN) {
                 bean.addPropertyValue(propertyName, parseBean(grandChildren.get(0), bean, parserContext));
             } else if (type == BeanTagAttribute.AttributeType.LISTBEAN) {
                 bean.addPropertyValue(propertyName, parseList(grandChildren, children.get(i), bean, parserContext));
             } else if (type == BeanTagAttribute.AttributeType.LISTVALUE) {
                 bean.addPropertyValue(propertyName, parseList(grandChildren, children.get(i), bean, parserContext));
             } else if (type == BeanTagAttribute.AttributeType.MAPVALUE) {
                 bean.addPropertyValue(propertyName, parseMap(grandChildren, children.get(i), bean, parserContext));
             } else if (type == BeanTagAttribute.AttributeType.MAPBEAN) {
                 bean.addPropertyValue(propertyName, parseMap(grandChildren, children.get(i), bean, parserContext));
             } else if (type == BeanTagAttribute.AttributeType.SETVALUE) {
                 bean.addPropertyValue(propertyName, parseSet(grandChildren, children.get(i), bean, parserContext));
             } else if (type == BeanTagAttribute.AttributeType.SETBEAN) {
                 bean.addPropertyValue(propertyName, parseSet(grandChildren, children.get(i), bean, parserContext));
             }
         }
         return;
     }
 
     /**
      * Adds the property value to the bean definition based on the name and value of the attribute.
      *
      * @param name - The name of the attribute.
      * @param value - The value of the attribute.
      * @param entries - The property entries for the over all tag.
      * @param bean - The bean definition being created.
      */
     private void processSingleValue(String name, String value, Map<String, BeanTagAttributeInfo> entries,
             BeanDefinitionBuilder bean) {
 
         if (name.toLowerCase().compareTo("parent") == 0) {
             // If attribute is defining the parent set it in the bean builder.
             bean.setParentName(value);
         } else if (name.toLowerCase().compareTo("abstract") == 0) {
             // If the attribute is defining the parent as  abstract set it in the bean builder.
             bean.setAbstract(Boolean.valueOf(value));
         } else if (name.toLowerCase().compareTo("id") == 0) {
             if (value.contains("Demo-CollectionGrouping-Section1")) {
                 System.out.println();
             }
 
             //nothing - insures that its erased
         } else {
             // If the attribute is not a reserved case find the property name form the connected map and add the new
             // property value.
 
             if (name.contains("-ref")) {
                 bean.addPropertyValue(name.substring(0, name.length() - 4), new RuntimeBeanReference(value));
             } else {
                 BeanTagAttributeInfo info = entries.get(name);
                 String propertyName;
 
                 if (info == null) {
                     propertyName = name;
                 } else {
                     propertyName = info.getName();
                 }
                 bean.addPropertyValue(propertyName, value);
             }
         }
     }
 
     /**
      * Finds the key of a map entry in the custom schema.
      *
      * @param grandchild - The map entry.
      * @return The object (bean or value) entry key
      */
     private Object findKey(Element grandchild) {
         String key = grandchild.getAttribute("key");
         if (!key.isEmpty()) {
             return key;
         } else {
             Element keyTag = DomUtils.getChildElementByTagName(grandchild, "spring:key");
             if (DomUtils.getChildElements(keyTag).size() == 0) {
                 return keyTag.getTextContent();
             } else {
                 return DomUtils.getChildElements(keyTag).get(0);
             }
         }
         //throw new Exception("Cannot find Map's key");
     }
 
     /**
      * Finds the value of a map entry in the custom schema.
      *
      * @param grandchild - The map entry.
      * @return The object (bean or value) entry value
      */
     private Object findValue(Element grandchild) {
         String value = grandchild.getAttribute("value");
         if (!value.isEmpty()) {
             return value;
         } else {
             Element valueTag = DomUtils.getChildElementByTagName(grandchild, "spring:value");
             if (DomUtils.getChildElements(valueTag).size() == 0) {
                 return valueTag.getTextContent();
             } else {
                 return DomUtils.getChildElements(valueTag).get(0);
             }
         }
         //throw new Exception("Cannot find Map's value");
     }
 
     /**
      * Finds the attribute type of the schema being used by the element.
      *
      * @param tag - The tag to check.
      * @return The schema attribute type.
      */
     private BeanTagAttribute.AttributeType findBeanType(Element tag) {
         int numberChildren = 0;
 
         // Checks if the user overrides the default attribute type of the schema.
         String overrideType = tag.getAttribute("overrideBeanType");
         if (!StringUtils.isEmpty(overrideType)) {
             if (overrideType.toLowerCase().compareTo("singlebean") == 0) {
                 return BeanTagAttribute.AttributeType.SINGLEBEAN;
             }
             if (overrideType.toLowerCase().compareTo("singlevalue") == 0) {
                 return BeanTagAttribute.AttributeType.SINGLEVALUE;
             }
             if (overrideType.toLowerCase().compareTo("listbean") == 0) {
                 return BeanTagAttribute.AttributeType.LISTBEAN;
             }
             if (overrideType.toLowerCase().compareTo("listvalue") == 0) {
                 return BeanTagAttribute.AttributeType.LISTVALUE;
             }
             if (overrideType.toLowerCase().compareTo("mapbean") == 0) {
                 return BeanTagAttribute.AttributeType.MAPBEAN;
             }
             if (overrideType.toLowerCase().compareTo("mapvalue") == 0) {
                 return BeanTagAttribute.AttributeType.MAPVALUE;
             }
             if (overrideType.toLowerCase().compareTo("setbean") == 0) {
                 return BeanTagAttribute.AttributeType.SETBEAN;
             }
             if (overrideType.toLowerCase().compareTo("setvalue") == 0) {
                 return BeanTagAttribute.AttributeType.SETVALUE;
             }
         }
 
         // Checks if the element is a list composed of standard types
         numberChildren = DomUtils.getChildElementsByTagName(tag, "spring:value").size();
         if (numberChildren > 0) {
             return BeanTagAttribute.AttributeType.LISTVALUE;
         }
 
         numberChildren = DomUtils.getChildElementsByTagName(tag, "spring:list").size();
         if (numberChildren > 0) {
             return BeanTagAttribute.AttributeType.LISTBEAN;
         }
 
         numberChildren = DomUtils.getChildElementsByTagName(tag, "spring:set").size();
         if (numberChildren > 0) {
             return BeanTagAttribute.AttributeType.SETBEAN;
         }
 
         // Checks if the element is a map
         numberChildren = DomUtils.getChildElementsByTagName(tag, "spring:entry").size();
         if (numberChildren > 0) {
             return BeanTagAttribute.AttributeType.MAPVALUE;
         }
 
         numberChildren = DomUtils.getChildElementsByTagName(tag, "spring:map").size();
         if (numberChildren > 0) {
             return BeanTagAttribute.AttributeType.MAPBEAN;
         }
 
         // Checks if the element is a list of beans
         numberChildren = DomUtils.getChildElements(tag).size();
         if (numberChildren > 1) {
             return BeanTagAttribute.AttributeType.LISTBEAN;
         }
 
         // Defaults to return the element as a single bean.
         return BeanTagAttribute.AttributeType.SINGLEBEAN;
     }
 
     /**
      * Parses a bean based on the namespace of the bean.
      *
      * @param tag - The Element to be parsed.
      * @param parent - The parent bean that the tag is nested in.
      * @param parserContext - Provided information and functionality regarding current bean set.
      * @return The parsed bean.
      */
     private Object parseBean(Element tag, BeanDefinitionBuilder parent, ParserContext parserContext) {
         if (tag.getNamespaceURI().compareTo("http://www.springframework.org/schema/beans") == 0) {
             return parseSpringBean(tag, parserContext);
         } else {
             return parseCustomBean(tag, parent, parserContext);
         }
     }
 
     /**
      * Parses a bean of the spring namespace.
      *
      * @param tag - The Element to be parsed.
      * @return The parsed bean.
      */
     private Object parseSpringBean(Element tag, ParserContext parserContext) {
         if (tag.getLocalName().compareTo("ref") == 0) {
             // Create the referenced bean by creating a new bean and setting its parent to the referenced bean
             // then replace grand child with it
             Element temp = tag.getOwnerDocument().createElement("bean");
             temp.setAttribute("parent", tag.getAttribute("bean"));
             tag = temp;
             return new RuntimeBeanReference(tag.getAttribute("parent"));
         }
 
         //peel off p: properties an make them actual property nodes - p-namespace does not work properly (unknown cause)
         Document document = tag.getOwnerDocument();
         NamedNodeMap attributes = tag.getAttributes();
         for(int i = 0; i < attributes.getLength(); i++){
             Node attribute = attributes.item(i);
             String name = attribute.getNodeName();
             if(name.startsWith("p:")){
                 Element property = document.createElement("property");
                 property.setAttribute("name", StringUtils.removeStart(name, "p:"));
                 property.setAttribute("value", attribute.getTextContent());
 
                 if(tag.getFirstChild() != null){
                     tag.insertBefore(property, tag.getFirstChild());
                 }
                 else{
                     tag.appendChild(property);
                 }
             }
         }
 
         // Create the bean definition for the grandchild and return it.
         BeanDefinitionParserDelegate delegate = parserContext.getDelegate();
         BeanDefinitionHolder bean = delegate.parseBeanDefinitionElement(tag);
 
         // Creates a custom name for the new bean.
         String name = bean.getBeanDefinition().getParentName() + "$Customchild" + beanNumber;
         if (tag.getAttribute("id") != null && !StringUtils.isEmpty(tag.getAttribute("id"))) {
             name = tag.getAttribute("id");
         } else {
             beanNumber++;
         }
 
         return new BeanDefinitionHolder(bean.getBeanDefinition(), name);
     }
 
     /**
      * Parses a bean of the custom namespace.
      *
      * @param tag - The Element to be parsed.
      * @param parent - The parent bean that the tag is nested in.
      * @param parserContext - Provided information and functionality regarding current bean set.
      * @return The parsed bean.
      */
     private Object parseCustomBean(Element tag, BeanDefinitionBuilder parent, ParserContext parserContext) {
         BeanDefinitionHolder bean;
         if (tag.getLocalName().compareTo("ref") == 0) {
             return new RuntimeBeanReference(tag.getAttribute("bean"));
 
         } else {
             BeanDefinition beanDefinition = parserContext.getDelegate().parseCustomElement(tag,
                     parent.getBeanDefinition());
 
             String name = beanDefinition.getParentName() + "$Customchild" + beanNumber;
             if (tag.getAttribute("id") != null && !StringUtils.isEmpty(tag.getAttribute("id"))) {
                 name = tag.getAttribute("id");
             } else {
                 beanNumber++;
             }
             bean = new BeanDefinitionHolder(beanDefinition, name);
         }
 
         return bean;
     }
 
     /**
      * Parses a list of elements into a list of beans/standard content.
      *
      * @param grandChildren - The list of beans/content in a bean property
      * @param child - The property tag for the parent.
      * @param parent - The parent bean that the tag is nested in.
      * @param parserContext - Provided information and functionality regarding current bean set.
      * @return A managedList of the nested content.
      */
     private ManagedList parseList(ArrayList<Element> grandChildren, Element child, BeanDefinitionBuilder parent,
             ParserContext parserContext) {
         ArrayList<Object> listItems = new ArrayList<Object>();
 
         for (int i = 0; i < grandChildren.size(); i++) {
             Element grandChild = grandChildren.get(i);
 
             if (grandChild.getTagName().compareTo("spring:value") == 0) {
                 listItems.add(grandChild.getTextContent());
             } else {
                 listItems.add(parseBean(grandChild, parent, parserContext));
             }
         }
 
         String merge = child.getAttribute("merge");
 
         ManagedList beans = new ManagedList(listItems.size());
 
         if (merge != null) {
             beans.setMergeEnabled(Boolean.valueOf(merge));
         }
 
         beans.addAll(listItems);
         return beans;
     }
 
     /**
      * Parses a list of elements into a set of beans/standard content.
      *
      * @param grandChildren - The set of beans/content in a bean property
      * @param child - The property tag for the parent.
      * @param parent - The parent bean that the tag is nested in.
      * @param parserContext - Provided information and functionality regarding current bean set.
      * @return A managedSet of the nested content.
      */
     private ManagedSet parseSet(ArrayList<Element> grandChildren, Element child, BeanDefinitionBuilder parent,
             ParserContext parserContext) {
         ManagedSet setItems = new ManagedSet();
 
         for (int i = 0; i < grandChildren.size(); i++) {
             Element grandChild = grandChildren.get(i);
 
             if (child.getTagName().compareTo("spring:value") == 0) {
                 setItems.add(grandChild.getTextContent());
             } else {
                 setItems.add(parseBean(grandChild, parent, parserContext));
             }
         }
 
         String merge = child.getAttribute("merge");
         if (merge != null) {
             setItems.setMergeEnabled(Boolean.valueOf(merge));
         }
 
         return setItems;
     }
 
     /**
      * Parses a list of elements into a map of beans/standard content.
      *
      * @param grandChildren - The list of beans/content in a bean property
      * @param child - The property tag for the parent.
      * @param parent - The parent bean that the tag is nested in.
      * @param parserContext - Provided information and functionality regarding current bean set.
      * @return A managedSet of the nested content.
      */
     private ManagedMap parseMap(ArrayList<Element> grandChildren, Element child, BeanDefinitionBuilder parent,
             ParserContext parserContext) {
         ManagedMap map = new ManagedMap();
         String merge = child.getAttribute("merge");
 
         for (int j = 0; j < grandChildren.size(); j++) {
             Object key = findKey(grandChildren.get(j));
             Object value = findValue(grandChildren.get(j));
             map.put(key, value);
         }
 
         if (merge != null) {
             map.setMergeEnabled(Boolean.valueOf(merge));
         }
 
         return map;
     }
 }