/// <summary>
/// Removes the first instance of an element that has the given name.
/// </summary>
/// <param name="name">The name of the element to remove.</param>
/// <returns>Returns true if the element was successfully removed. False if it did not exist within this template.</returns>
public bool RemoveElementByName(string name)
{
if (_Children == null || _Children.Count < 1 || name == null || name.Length < 1)
{
return(false);
}
BaseElement elm = null;
foreach (BaseElement element in _Children)
{
if (element.Name == name)
{
elm = element;
}
}
if (elm != null)
{
bool result = RemoveElement(elm);
elm.Parent = null;
return(result);
}
return(false);
}
/// <summary>
/// This method performs reconciliation on all existing elements so that the old
/// template matches this one.
/// Then it adds new elements to the old template. Finally, it tries to reconcile
/// elements that have been fundamentally changed in the new template. Failing that,
/// elements that cannot be resolved are simply removed until the old template
/// matches the new one.
/// </summary>
/// <param name="oldTemplate"></param>
/// <returns></returns>
public bool ReconcileElementProperties(BaseElement oldTemplate)
{
if (!this.Guid.Equals(oldTemplate.Guid))
{
return(false);
}
Type sourceType = this.GetType();
Type oldType = this.GetType();
//first, let's do the easy stuff and update existing properties for both templates
foreach (var property in sourceType.GetProperties(BindingFlags.Public | BindingFlags.Instance))
{
var targetProperty = oldType.GetProperty(property.Name, BindingFlags.Public | BindingFlags.Instance);
if (targetProperty != null &&
targetProperty.CanWrite &&
targetProperty.GetCustomAttribute <ReconcilableProp>(true) != null &&
property.GetCustomAttribute <ShallowElementCloneAttribute>(true) != null)
{
targetProperty.SetValue(oldTemplate, property.GetValue(this, null), null);
}
}
List <IElement> newElements = new List <IElement>();
//now we are going to loop through the list of elements within the template
//and try to reconcile their properties.
foreach (IElement element in _Children)
{
bool notCopied = true;
//yucky inner-loop that loop that looks
//for the matching element within the old template.
foreach (BaseElement oldElement in oldTemplate.Children)
{
//this automatically checks the Guids to see if
//they are the matching element. No worries here.
//It will simply return if there is not a match...
//or you know... they generated the same Guid somehow ;)
if (element.ReconcileElementProperties(oldElement))
{
notCopied = false;
break;
}
}
//if the element couldn't be found in the old template, we'll need to
//add it to a list that will be appened later
if (notCopied)
{
newElements.Add(element);
}
}
//now something tricky. We need to add elements to
//the old template to match the new one.
foreach (IElement append in newElements)
{
oldTemplate.AddElement(append.GetShallowClone());
}
return(false);
}
/// <summary>
/// Copies this element to another element using shallow copying
/// of all basic properties. Child elements however, are still
/// deeply copied using recursion. This will not handle indexed properties.
/// </summary>
/// <returns></returns>
public BaseElement GetShallowClone()
{
BaseElement dest = Activator.CreateInstance(this.GetType()) as BaseElement;
if (dest == null)
{
return(null);
}
Type sourceType = this.GetType();
Type targetType = dest.GetType();
//copy all values of all elements marked with a clone attribute
foreach (var property in sourceType.GetProperties(BindingFlags.Public | BindingFlags.Instance))
{
var targetProperty = targetType.GetProperty(property.Name, BindingFlags.Public | BindingFlags.Instance);
if (targetProperty != null &&
targetProperty.CanWrite &&
targetProperty.PropertyType.IsAssignableFrom(property.PropertyType) &&
targetProperty.GetCustomAttribute <ShallowElementCloneAttribute>(true) != null &&
property.GetCustomAttribute <ShallowElementCloneAttribute>(true) != null)
{
targetProperty.SetValue(dest, property.GetValue(this, null), null);
}
else if (targetProperty != null &&
targetProperty.CanWrite &&
targetProperty.PropertyType.IsAssignableFrom(property.PropertyType) &&
targetProperty.GetCustomAttribute <DeepElementCloneAttribute>(true) != null &&
property.GetCustomAttribute <DeepElementCloneAttribute>(true) != null)
{
try
{
targetProperty.SetValue(dest, Utils.ObjectHelper.Clone(property.GetValue(this, null)), null);
}
catch (ArgumentException e)
{
MessageBox.Show("Failed to deep copy the property '" + property.Name + "' of the element '" + this._Name + "'.\n" + e.Message);
}
}
else if (
targetProperty != null &&
targetProperty.CanWrite &&
targetProperty.PropertyType.IsAssignableFrom(property.PropertyType) &&
targetProperty.GetCustomAttribute <ContentElementCloneAttribute>(true) != null &&
property.GetCustomAttribute <ContentElementCloneAttribute>(true) != null)
{
this.DeepClone(property, this, targetProperty, dest);
}
}
//manually copy InstanceProperties
//We need to generate the InstanceEditProperty controls and bind them here.
dest.BindInstanceEditProps();
//TODO: set default values to binding property
//now deep shallow-copy of the children
foreach (BaseElement child in _Children)
{
dest.Children.Add(child.GetShallowClone());
}
//we use reflection to get the private Guid value.
//We do this in an effort to avoid letting overriding
//classes mess with the Guid
FieldInfo sourceGuid = sourceType.GetField("_Guid", BindingFlags.NonPublic | BindingFlags.Instance);
FieldInfo destGuid = targetType.GetField("_Guid", BindingFlags.NonPublic | BindingFlags.Instance);
destGuid.SetValue(dest, sourceGuid.GetValue(this));
return(dest);
}
/// <summary>
/// Adds a new element to the template.
/// </summary>
/// <param name="element"></param>
public virtual void AddElement(BaseElement element)
{
InitElementList();
_Children.Add(ConvertElement(element));
element.Parent = this;
}
/// <summary>
/// This default implementation in fact does not peform a deep copy. It is a stand-in
/// shallow copy using reflection of the object's proeprties. For a proper deep-copy,
/// override this method and implement according to the Element's _Content datatype.
/// </summary>
/// <param name="sourceProp"></param>
/// <param name="sourceElm"></param>
/// <param name="destProp"></param>
/// <param name="destElm"></param>
protected virtual void DeepClone(PropertyInfo sourceProp, BaseElement sourceElm, PropertyInfo destProp, BaseElement destElm)
{
destProp.SetValue(destElm, sourceProp.GetValue(sourceElm, null), null);
}
