/**
    * Copyright 2005-2012 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.util.documentserializer;
  
  import org.apache.commons.lang.StringUtils;
  import org.kuali.rice.krad.util.KRADConstants;
  
  import java.util.StringTokenizer;
  
  /**
   * This is a implementation of a trie/prefix tree of that contains metadata about property serializability
   * during the document serialization process.
   *
   */
  public class PropertySerializerTrie {  
      private static final String PROPERTY_NAME_COMPONENT_SEPARATOR = ".";
      private PropertySerializerTrieNode rootNode;
      
      public PropertySerializerTrie() {
          rootNode = new PropertySerializerTrieNode(KRADConstants.EMPTY_STRING, KRADConstants.EMPTY_STRING);
      }
      
      /**
       * Registers a new serializable property so that all of its primitives are serialized.  All nesting properties
       * will be serialized only to render open/close tags to maintain consistency with the document structure, unless
       * they are registered as well.
       * 
       * For example, if only property "document.a.b" is registered, then the XML will look like the following:
       * 
       * <document>
       *     <a>
       *         <b>
       *             <primitiveOfB>valueOfPrimitive</primitiveOfB>
       *         </b>
       *     </a>
       * </document>
       * 
       * That is, primitives of "document" and "document.a" will not be serialized unless those property strings are registered.
       * 
       * @param propertyName
       * @param setPropertySerializabilityToObjectAndAllPrimitivesForAll
       */
      public void addSerializablePropertyName(String propertyName, boolean setPropertySerializabilityToObjectAndAllPrimitivesForAll) {
          if (propertyName == null) {
              throw new IllegalArgumentException("Null attribute name specified");
          }
          if (StringUtils.isBlank(propertyName)) {
              rootNode.setPropertySerializabilityToObjectAndAllPrimitives();
          }
          else {
              StringTokenizer tok = new StringTokenizer(propertyName, PROPERTY_NAME_COMPONENT_SEPARATOR, false);
              StringBuilder buf = new StringBuilder();
  
              if(setPropertySerializabilityToObjectAndAllPrimitivesForAll)
              	rootNode.setPropertySerializabilityToObjectAndAllPrimitives();
  
              PropertySerializerTrieNode currentNode = rootNode;
              while (tok.hasMoreTokens()) {
                  String attributeNameComponent = tok.nextToken();
                  validateAttributeNameComponent(attributeNameComponent);
  
                  buf.append(attributeNameComponent);
  
                  // create a new node or retrieve existing node for this name component
                  PropertySerializerTrieNode childNode = currentNode.getChildNode(attributeNameComponent);
                  if (childNode == null) {
                      childNode = new PropertySerializerTrieNode(buf.toString(), attributeNameComponent);
                      currentNode.addChildNode(childNode);
                  }
                  
                  if (tok.hasMoreTokens()) {
                      buf.append(PROPERTY_NAME_COMPONENT_SEPARATOR);
                  }
                  currentNode = childNode;
                  if(setPropertySerializabilityToObjectAndAllPrimitivesForAll)
                  	currentNode.setPropertySerializabilityToObjectAndAllPrimitives();
              }
              
              currentNode.setPropertySerializabilityToObjectAndAllPrimitives();
          }
      }
      
      /**
       * Retrieves the metadata about the given property name
       * 
       * @param propertyName
      * @return
      */
     public PropertySerializabilityMetadata getPropertySerializabilityMetadata(String propertyName) {
         if (propertyName == null) {
             throw new IllegalArgumentException("Null attribute name specified");
         }
         if (StringUtils.isBlank(propertyName)) {
             return rootNode;
         }
         else {
             StringTokenizer tok = new StringTokenizer(propertyName, PROPERTY_NAME_COMPONENT_SEPARATOR, false);
             
             PropertySerializerTrieNode currentNode = rootNode;
             while (tok.hasMoreTokens()) {
                 String attributeNameComponent = tok.nextToken();
                 validateAttributeNameComponent(attributeNameComponent);
 
                 // retrieve the child node for this name component
                 PropertySerializerTrieNode childNode = currentNode.getChildNode(attributeNameComponent);
                 if (childNode == null) {
                     // we didn't find a child node, so we know that something wasn't added with the prefix we're processing
                     return null;
                 }
                 else {
                     // keep going until we hit the last token, at which case we'll get out of this loop
                     currentNode = childNode;
                 }
             }
             return currentNode;
         }
     }
     
     /**
      * Returns the root node of the trie
      * 
      * @return
      */
     public PropertySerializabilityMetadata getRootPropertySerializibilityMetadata() {
         return rootNode;
     }
     
     protected void validateAttributeNameComponent(String attributeNameComponent) {
         if (StringUtils.isBlank(attributeNameComponent)) {
             throw new IllegalArgumentException("Blank attribute name component specified");
         }
     }
 }