gistfile1.txt

/// I want to create tree like structures of "Elements"
/// Each Element has GeneralInformation (a name and a description)
/// There are two types of "Parent elements", e.g. elements that can have child elements: 
/// * Links that have at most one dynamic child, two related properties and which can dynamically change their child with an update method
/// * Collections that have an arbitrary number of children, but don't provide an update method
/// Children can be any implementation of the base interface below, in particular elements, collections and links can all be children of collections and links 


// Base interface
// Each element must have GeneralInformation
// Single responsibility principle enforces to put logic in GeneralInformation
// Law of Demeter enforces to proxy ElementName and ElementDescription in GeneralInformation
// This is also the base type for children, any implementation of any derived interface can be a child  
public interface IElement
{
  IGeneralInformation GeneralInformation { get; }
  string ElementName { get; set; }
  string ElementDescription { get; set; }
}

// Extended class type 1 - links can have exactly one child of arbitrary type
// We must inherit from IElement since we want to use ILink inmplementations as children 
// Single responsibility principle enforces to put logic in LinkInformation
// Law of Demeter enforces to proxy ReferencedElement and UpdateLink in GeneralInformation
public interface ILink : IElement
{
  ILinkInformation LinkInformation { get; }
  
  IElement ReferencedElement { get; }
  void UpdateLink(object arg);
}


// base functionality
public interface IGeneralInformation
{
    string ElementName { get; set; }
    string ElementDescription { get; set; }
}

// extended functionality type 1
public interface ILinkInformation
{
    bool IsTargetRelative { get; set; }
    bool IsTargetGlobal { get; set; }
    IElement ReferencedElement { get; }
    
    void UpdateLink(object arg);
}

// extended functionality type 2
public interface ICollectionInformation
{
    IList<IElement> listOfChildren { get; }
}