public void InsertAfter(LinkMember node)
{
if (this == node)
{
return;
}
LinkMember after;
if ((after = NextSibling) is null)
{
Parent.Add(node);
}
else
{
if (IsAncestorOf(node))
{
return;
}
Mend(END, after, node);
node.Parent = Parent;
}
}
public void InsertBefore(LinkMember node)
{
if (this == node)
{
return;
}
//Can't insert itself before itself.
var first = PreviousSibling;
if (first is null)
{
Parent.Prepend(node);
//If previous sibling is null, we have to perform Parent.Prepend(node)
}
else
{
if (IsAncestorOf(node))
{
return;
}
//IsAncestorOf is checked in a similar way in Parent.Prepend.
//The check for PreviousSibling being null is quicker than IsAncestorOf
//so calling IsAncestorOf here is more appropriate than calling first.
Mend(first.END, this, node);
node.Parent = Parent;
}
}
private void Mend(LinkMember start, LinkMember finish, LinkMember node)
{
node.Pop();
start.SetNext(node);
node.SetPrev(start);
finish.SetPrev(node.END);
node.END.SetNext(finish);
}
public void Add(LinkMember node)
{
if (this == node || IsAncestorOf(node))
{
return;
}
Mend(END.Prev, END, node);
node.Parent = this;
}
public void Prepend(LinkMember node)
{
if (this == node || IsAncestorOf(node))
{
return;
}
Mend(this, Next, node);
node.Parent = this;
}
public LinkMember(object value)
{
END = new LinkMember()
{
Value = "END"
};
Value = value;
Next = END;
END.Prev = this;
END.Parent = this;
}
public void Replace(LinkMember remove, LinkMember insert)
{
remove.InsertAfter(insert);
remove.Pop();
}
public bool IsAncestorOf(LinkMember linkMember) => GetParents().FirstOrDefault(parent => parent == linkMember) is not null;
public void SetPrev(LinkMember node) => Prev = node;
public void SetNext(LinkMember node) => Next = node;