/**
 * This method checks to see if there are any <code>Label</code>
 * objects remaining in the provided map that are required. This is
 * used when deserialization is performed to ensure the the XML
 * element deserialized contains sufficient details to satisfy the
 * XML schema class annotations. If there is a required label that
 * remains it is reported within the exception thrown.
 * 
 * @param node this is the node that contains the contact value
 * @param map this is the map to check for remaining labels
 * @param source this is the object that has been deserialized 
 */
private void validate(InputNode node, LabelMap map, Object source) throws Exception {
   Class expect = context.getType(type, source);
   Position line = node.getPosition();

   for(Label label : map) {
      if(label.isRequired() && revision.isEqual()) {
         throw new ValueRequiredException("Unable to satisfy %s for %s at %s", label, expect, line);
      }
      Object value = label.getEmpty(context);
      
      if(value != null) {
         criteria.set(label, value);
      }
   }      
}
 

@Override
public T read(InputNode node) throws Exception {
    Map<String, Field> entityFields = getEntityFields();
    T entity = entityClass.newInstance();
    List<org.w3c.dom.Element> anyElements = entity.getAny();
    InputNode childNode;
    while((childNode = node.getNext()) != null) {
        if (entityFields.containsKey(childNode.getName())) {
            Field field = entityFields.get(childNode.getName());
            getSetterForField(field).invoke(entity, serializer.read(field.getType(), childNode));
        } else if (childNode.getPrefix() != null && !childNode.getPrefix().isEmpty()) {
            org.w3c.dom.Element element = ElementConverter.read(childNode);
            anyElements.add(element);
        } else {
            // Probably a WebDAV field we don't support yet
            skipChildrenOfNode(childNode);
        }
    }
    return entity;
}
 

@Override
public T read(InputNode node) throws Exception {
    Map<String, Field> entityFields = getEntityFields();
    T entity = entityClass.newInstance();
    List<org.w3c.dom.Element> anyElements = entity.getAny();
    InputNode childNode;
    while((childNode = node.getNext()) != null) {
        if (entityFields.containsKey(childNode.getName())) {
            Field field = entityFields.get(childNode.getName());
            getSetterForField(field).invoke(entity, serializer.read(field.getType(), childNode));
        } else if (childNode.getPrefix() != null && !childNode.getPrefix().isEmpty()) {
            org.w3c.dom.Element element = ElementConverter.read(childNode);
            anyElements.add(element);
        } else {
            // Probably a WebDAV field we don't support yet
            skipChildrenOfNode(childNode);
        }
    }
    return entity;
}
 

public void testTwo() throws Exception {
   Context context = new Source(new TreeStrategy(), new Support(), new Session());
   PrimitiveList primitive = new PrimitiveList(context, new ClassType(List.class), new ClassType(String.class), "entry");
   InputNode node = NodeBuilder.read(new StringReader(TWO));
   Object value = primitive.read(node);
   
   assertEquals(value.getClass(), Vector.class);
   
   Vector vector = (Vector) value;
   
   assertEquals(vector.get(0), "one");
   assertEquals(vector.get(1), "two");
   
   InputNode newNode = NodeBuilder.read(new StringReader(TWO));
   
   assertTrue(primitive.validate(newNode)); 
}
 

/**
 * This is used to read the <code>Value</code> which will be used 
 * to represent the deserialized object. If there is an annotation
 * present then the value will contain an object instance. If it
 * does not then it is up to the internal strategy to determine 
 * what the returned value contains.
 * 
 * @param type this is the type that represents a method or field
 * @param node this is the node representing the XML element
 * @param value this is the value from the internal strategy
 * 
 * @return the value representing the deserialized value
 */
private Value read(Type type, NodeMap<InputNode> node, Value value) throws Exception {
   Converter converter = scanner.getConverter(type, value);
   InputNode parent = node.getNode();
   
   if(converter != null) {
      Object data = converter.read(parent);
      Class actual = type.getType();
      
      if(value != null) {
         value.setValue(data);
      }
      return new Reference(value, data, actual);
   }
   return value;
}
 

public Something read(InputNode node) throws Exception {
   Object source = node.getSource();
   Element element = (Element)source;
   NodeList elements = element.getChildNodes();
   String child1 = null;
   String child2 = null;
   String text = "";
   for(int i = 0; i < elements.getLength(); i++) {
      Node next = elements.item(i);
      if(next.getNodeType() == Node.TEXT_NODE) {
         text += next.getNodeValue();
      }
      if(next.getNodeType() == Node.ELEMENT_NODE) {
         if(next.getNodeName().equals("child1")) {
            child1 = next.getTextContent();
         }
         if(next.getNodeName().equals("child2")) {
            child2 = next.getTextContent();
         }
      }
   }
   return new Something(child1, child2, text.trim());
}
 

/**
 * This method is used to read the version from the provided input
 * node. Once the version has been read it is used to determine how
 * to deserialize the object. If the version is not the initial
 * version then it is read in a manner that ignores excessive XML
 * elements and attributes. Also none of the annotated fields or
 * methods are required if the version is not the initial version.
 * 
 * @param node the XML element contact values are deserialized from
 * @param source this object whose contacts are to be deserialized
 * @param schema this object visits the objects contacts
 */
private void readVersion(InputNode node, Object source, Schema schema) throws Exception {
   Label label = schema.getVersion();
   Class expect = type.getType();
   
   if(label != null) {
      String name = label.getName();
      NodeMap<InputNode> map = node.getAttributes();
      InputNode value = map.remove(name);
      
      if(value != null) {
         readVersion(value, source, label);
      } else {
         Version version = context.getVersion(expect);
         Double start = revision.getDefault();
         Double expected = version.revision();
         
         criteria.set(label, start);
         revision.compare(expected, start);
      }
   }
}
 

/**
 * This <code>populate</code> method will read the XML element map 
 * from the provided node and deserialize its children as entry types.
 * Each entry type must contain a key and value so that the entry 
 * can be inserted in to the map as a pair. If either the key or 
 * value is composite it is read as a root object, which means its
 * <code>Root</code> annotation must be present and the name of the
 * object element must match that root element name.
 * 
 * @param node this is the XML element that is to be deserialized
 * @param result this is the map object that is to be populated
 * 
 * @return this returns the item to attach to the object contact
 */
private Object populate(InputNode node, Object result) throws Exception {
   Map map = (Map) result;                 
   
   while(true) {
      InputNode next = node.getNext();
     
      if(next == null) {
         return map;
      }
      Object index = key.read(next);
      Object item = value.read(next);
         
      map.put(index, item); 
   }
}
 

/**
 * This <code>readElement</code> method is used for deserialization
 * of the provided node object using a delegate converter. This is
 * typically another <code>Composite</code> converter, or if the
 * node is an attribute a <code>Primitive</code> converter. When
 * the delegate converter has completed the deserialized value is
 * assigned to the contact.
 * 
 * @param node this is the node that contains the contact value
 * @param source the type of the object that is being deserialized
 * @param section this is the section to read the element from
 * @param map this is the map that contains the label objects
 */
private void readElement(InputNode node, Object source, Section section, LabelMap map) throws Exception {
   String name = node.getName();
   String path = section.getPath(name); 
   Label label = map.getLabel(path);      

   if(label == null) {
      label = criteria.resolve(path);
   }
   if(label == null) {
      Position line = node.getPosition();
      Class expect = context.getType(type, source);
      
      if(map.isStrict(context) && revision.isEqual()) {              
         throw new ElementException("Element '%s' does not have a match in %s at %s", path, expect, line);
      } else {
         node.skip();                 
      }
   } else {
      readUnion(node, source, map, label);
   }         
}
 

/**
 * This <code>readElements</code> method reads the elements from 
 * the provided XML element. This will iterate over all elements
 * within the element and convert those elements to primitives or
 * composite objects depending on the contact annotation.
 * <p>
 * Once all elements within the XML element have been evaluated
 * the <code>Schema</code> is checked to ensure that there are no
 * required contacts annotated with the <code>Element</code> that
 * remain. If any required element remains an exception is thrown. 
 * 
 * @param node this is the XML element to be evaluated
 * @param source the type of the object that is being deserialized
 * @param section the XML section that contains the structure
 */
private void readElements(InputNode node, Object source, Section section) throws Exception {
   LabelMap map = section.getElements();
   InputNode child = node.getNext();
   
   while(child != null) {         
      String name = child.getName();
      Section block = section.getSection(name);         
      
      if(block != null) {
         readSection(child, source, block);
      } else { 
         readElement(child, source, section, map);
      }
      child = node.getNext();
   } 
   validate(node, map, source);
}
 

/**
 * This <code>read</code> method will read the XML element list from
 * the provided node and deserialize its children as entry types.
 * This ensures each entry type is deserialized as a root type, that 
 * is, its <code>Root</code> annotation must be present and the
 * name of the entry element must match that root element name.
 * 
 * @param node this is the XML element that is to be deserialized
 * @param list this is the array that is to be deserialized
 * 
 * @return this returns the item to attach to the object contact
 */  
public Object read(InputNode node, Object list) throws Exception{
   int length = Array.getLength(list);
    
   for(int pos = 0; true; pos++) {
      Position line = node.getPosition();
      InputNode next = node.getNext();
     
      if(next == null) {
         return list;
      }
      if(pos >= length){
          throw new ElementException("Array length missing or incorrect for %s at %s", type, line);
      }
      read(next, list, pos);
   } 
}
 

/**
 * This <code>populate</code> method wll read the XML element list 
 * from the provided node and deserialize its children as entry types.
 * This will deserialize each entry type as a primitive value. In
 * order to do this the parent string provided forms the element.
 * 
 * @param node this is the XML element that is to be deserialized
 * @param result this is the collection that is to be populated
 * 
 * @return this returns the item to attach to the object contact
 */ 
private Object populate(InputNode node, Object result) throws Exception {
   Collection list = (Collection) result;                 
   
   while(true) {
      InputNode next = node.getNext();
     
      if(next == null) {
         return list;
      }
      list.add(root.read(next));
   }
}
 

@Override
public Integer read(InputNode node) throws Exception {
    try {
        String value = node.getValue();
        return Integer.valueOf(node.getValue());
    }catch (Exception e){
        return 0;
    }
}
 

private boolean isProtected(InputNode node) throws Exception {
    InputNode isProtectedNode = node.getAttribute("Protected");
    if (isProtectedNode == null) {
        return false;
    }

    String value = isProtectedNode.getValue();
    return value.equalsIgnoreCase("true");
}
 

@Override
public Date read(InputNode inputNode) throws Exception {
    String value = inputNode.getValue();
    if (value.equals("${creationDate}")) {
        return new Date();
    }
    return Helpers.toDate(value);
}
 

public void testZero() throws Exception {
   Context context = new Source(new TreeStrategy(), new Support(), new Session());
   PrimitiveArray primitive = new PrimitiveArray(context, new ClassType(String[].class), new ClassType(String.class), "entry");
   InputNode node = NodeBuilder.read(new StringReader(ZERO));
   Object value = primitive.read(node);
   
   assertEquals(value.getClass(), String[].class);
   
   InputNode newNode = NodeBuilder.read(new StringReader(ZERO));
   
   assertTrue(primitive.validate(newNode)); 
}
 

public void testPrimitiveCycle() throws Exception {
   Context context = new Source(new CycleStrategy(), new Support(), new Session());
   Primitive primitive = new Primitive(context, new ClassType(String.class));
   InputNode node = NodeBuilder.read(new StringReader(CYCLE_1));
   Object value = primitive.read(node);
   
   assertEquals("some text", value);
   
   // Need to use a different id for validate as reading has created the object
   // and an exception is thrown that the value already exists if id=1 is used 
   InputNode newNode = NodeBuilder.read(new StringReader(CYCLE_2));
   
   assertTrue(primitive.validate(newNode)); 
}
 

/**
 * This <code>validate</code> method wll validate the XML element 
 * list against the provided node and validate its children as entry 
 * types. This ensures each entry type is validated as a root type, 
 * that is, its <code>Root</code> annotation must be present and the
 * name of the entry element must match that root element name.
 * 
 * @param node this is the XML element that is to be validated
 * @param type this is the array type used to create the array
 * 
 * @return true if the element matches the XML schema class given 
 */  
private boolean validate(InputNode node, Class type) throws Exception{
   while(true) {
      InputNode next = node.getNext();
     
      if(next == null) {
         return true;
      }
      if(!next.isEmpty()) {
         root.validate(next, type);
      }
   }
}
 

public Cat read(InputNode source) throws Exception{
   int age = 0;
   String name = null;     
   while(true) {
      InputNode node = source.getNext();
      if(node == null) {
         break;
      }else if(node.getName().equals(ELEMENT_NAME)) {
         name = node.getValue();
      }else if(node.getName().equals(ELEMENT_AGE)){
         age = Integer.parseInt(node.getValue().trim());
      } 
   }
   return new Cat(name, age);
}
 

/**
 * This <code>validate</code> method is used to perform validation
 * of the provided node object using a delegate converter. This is
 * typically another <code>Composite</code> converter, or if the
 * node is an attribute a <code>Primitive</code> converter. If this
 * fails validation then an exception is thrown to report the issue.
 * 
 * @param node this is the node that contains the contact value
 * @param label this is the label used to create the converter
 */
private void validate(InputNode node, Label label) throws Exception {    
   Converter reader = label.getConverter(context);      
   Position line = node.getPosition();
   Class expect = type.getType();
   boolean valid = reader.validate(node);
 
   if(valid == false) {     
     throw new PersistenceException("Invalid value for %s in %s at %s", label, expect, line);
   }
   criteria.set(label, null);
}
 

/**
 * This method will instantiate an object of the field type, or if
 * the <code>Strategy</code> object can resolve a class from the
 * XML element then this is used instead. If the resulting type is
 * abstract or an interface then this method throws an exception.
 * 
 * @param node this is the node to check for the override
 * 
 * @return this returns an instance of the resulting type
 */       
@Override
public Instance getInstance(InputNode node) throws Exception {
   Value value = getOverride(node);
   Class expect = getType();
 
   if(value == null) { 
      if(!isInstantiable(expect)) {
         throw new InstantiationException("Cannot instantiate %s for %s", expect, type);              
      }
      return context.getInstance(expect);         
   }
   return new ObjectInstance(context, value);      
}
 

@Override
public Property read(InputNode node) throws Exception {
	Property property = new Property();
	InputNode childNode = node.getNext();
	if (childNode != null) {
		property.setProperty(ElementConverter.read(childNode));
	}
	return property;
}
 

/**
 * The <code>readResolve</code> method is used to determine if there 
 * is a resolution method which can be used to substitute the object
 * deserialized. The resolve method is used when an object wishes 
 * to provide a substitute within the deserialized object graph.
 * This acts as an equivalent to the Java Object Serialization
 * <code>readResolve</code> method for the object deserialization.
 * 
 * @param node the XML element object provided as a replacement
 * @param source the type of the object that is being deserialized
 * @param caller this is used to invoke the callback methods
 * 
 * @return this returns a replacement for the deserialized object
 */
private Object readResolve(InputNode node, Object source, Caller caller) throws Exception {
   if(source != null) {
      Position line = node.getPosition();
      Object value = caller.resolve(source);
      Class expect = type.getType();
      Class real = value.getClass();
   
      if(!expect.isAssignableFrom(real)) {
         throw new ElementException("Type %s does not match %s at %s", real, expect, line);              
      }
      return value;
   }
   return source;
}
 

/**
 * This method is used to read the value value from the node. The 
 * value read from the node is resolved using the template filter.
 * If the value value can not be found according to the annotation
 * attributes then an exception is thrown.
 * 
 * @param node this is the node to read the value object from
 * 
 * @return this returns the value deserialized from the node
 */ 
public Object read(InputNode node) throws Exception {
   Class expect = type.getType();
   String name = entry.getValue();
   
   if(!entry.isInline()) {
      if(name == null) {
         name = context.getName(expect);
      }
      return readElement(node, name);
   }
   return readAttribute(node, name);
}
 

/**
 * This <code>read</code> method will perform a read using the
 * provided object with the repeater. Reading with this method
 * ensures that any additional XML elements within the source
 * will be added to the value.
 * 
 *  @param node this is the node that contains the extra data
 *  
 *  @return this will return the original deserialized object
 */
public boolean validate(InputNode node) throws Exception {
   Position line = node.getPosition();
   String name = node.getName();         
   
   if(reader instanceof Repeater) {
      Repeater repeat = (Repeater) reader;
      
      return repeat.validate(node);
   }
   throw new PersistenceException("Element '%s' declared twice at %s", name, line);
}
 

public void read(Type type, NodeMap<InputNode> node){
   InputNode element = node.getNode();
   if(element.isRoot()) {
      Object source = element.getSource();
      Class sourceType = source.getClass();
      Class itemType = type.getType();
      System.out.printf(">>>>> ELEMENT=[%s]%n>>>>> TYPE=[%s]%n>>>>> SOURCE=[%s]%n", element, itemType, sourceType);
   }
}
 

/**
 * This method is used to read the key value from the node. The 
 * value read from the node is resolved using the template filter.
 * If the key value can not be found according to the annotation
 * attributes then the node is considered as null and is valid.
 * 
 * @param node this is the node to read the key value from
 * 
 * @return this returns the value deserialized from the node
 */   
public boolean validate(InputNode node) throws Exception {
   Class expect = type.getType();
   String name = entry.getKey();
        
   if(name == null) {
      name = context.getName(expect);
   }
   if(!entry.isAttribute()) {         
      return validateElement(node, name);
   }
   return validateAttribute(node, name);
}
 

/**
 * This <code>populate</code> method wll read the XML element list 
 * from the provided node and deserialize its children as entry types.
 * This will each entry type is deserialized as a root type, that 
 * is, its <code>Root</code> annotation must be present and the
 * name of the entry element must match that root element name.
 * 
 * @param node this is the XML element that is to be deserialized
 * @param result this is the collection that is to be populated
 * 
 * @return this returns the item to attach to the object contact
 */ 
private Object populate(InputNode node, Object result) throws Exception {
   Collection list = (Collection) result;                 
   
   while(true) {
      InputNode next = node.getNext();
      Class expect = entry.getType();
     
      if(next == null) {
         return list;
      }
      list.add(root.read(next, expect));
   }
}
 

/**
 * This <code>validate</code> method will validate the XML element 
 * list from the provided node and deserialize its children as entry 
 * types. This takes each entry type and validates it as a root type, 
 * that is, its <code>Root</code> annotation must be present and the
 * name of the entry element must match that root element name.
 * 
 * @param node this is the XML element that is to be validated
 * 
 * @return true if the element matches the XML schema class given 
 */ 
public boolean validate(InputNode node) throws Exception{
   Instance value = factory.getInstance(node);
   
   if(!value.isReference()) {
      Object result = value.setInstance(null);
      Class type = value.getType();
         
      return validate(node, type);
   }
   return true; 
}
 

public void testSimpleList() throws Exception {
   Context context = getContext();
   Group group = getGroup();
   Type type = new ClassType(CompositeListUnionTest.class);
   List<Shape> list = new ArrayList<Shape>();
   Expression expression = new PathParser("some/path", type, new Format());
   CompositeListUnion union = new CompositeListUnion(
         context,
         group,
         expression,
         type);
   InputNode node = NodeBuilder.read(new StringReader(SOURCE));
   
   InputNode circle = node.getNext();
   union.read(circle, list);
   
   InputNode square = node.getNext();
   union.read(square, list);
   
   InputNode triangle = node.getNext();
   union.read(triangle, list);
   
   assertEquals(list.get(0).getClass(), Circle.class);
   assertEquals(list.get(1).getClass(), Square.class);
   assertEquals(list.get(2).getClass(), Triangle.class);
   
   OutputNode output = NodeBuilder.write(new PrintWriter(System.out), new Format(3));
   OutputNode parent = output.getChild("parent");
   
   union.write(parent, list);
}