module ActiveLdap::Acts::Tree

def self.included(base)
  base.class_eval do
    extend(ClassMethods)
    association_accessor(:children) do |target|
      Association::Children.new(target, {})
    end
  end
end

def ancestors
  node, nodes = self, []
  nodes << node = node.parent while node.parent
  nodes
end

def parent
  if base == self.class.base
    nil
  else
    find(:first, :base => base, :scope => :base)
  end
end

def parent=(entry)
  if entry.is_a?(String) or entry.is_a?(DN)
    base = entry.to_s
  elsif entry.respond_to?(:dn)
    base = entry.dn.to_s
    if entry.respond_to?(:clear_association_cache)
      entry.clear_association_cache
    end
  else
    message = _("parent must be an entry or parent DN: %s") % entry.inspect
    raise ArgumentError, message
  end
  unless new_entry?
    begin
      self.class.modify_rdn_entry(dn, "#{dn_attribute}=#{id}",
                                  true, base,
                                  :connection => connection)
    rescue NotImplemented
      self.class.delete_entry(dn, :connection => connection)
      @new_entry = true
    end
  end
  self.dn = "#{dn_attribute}=#{id},#{base}"
  save if new_entry?
end

def root
  node = self
  node = node.parent while node.parent
  node
end

def self_and_siblings
  parent ? parent.children : [self]
end

def siblings
  self_and_siblings - [self]
end