openproject/lib/redmine/menu_manager/tree_node.rb

require 'tree' # gem install rubytree

class Redmine::MenuManager::TreeNode < Tree::TreeNode
  attr_reader :last_items_count

  def initialize(name, content = nil)
    @last_items_count = 0
    super
  end

  # Adds the specified child node to the receiver node.  The child node's
  # parent is set to be the receiver.  The child is added as the first child in
  # the current list of children for the receiver node.
  def prepend(child)
    raise "Child already added" if @childrenHash.has_key?(child.name)

    @childrenHash[child.name]  = child
    @children = [child] + @children
    child.parent = self
    return child

  end

  # Adds the specified child node to the receiver node.  The child node's
  # parent is set to be the receiver.  The child is added at the position
  # into the current list of children for the receiver node.
  def add_at(child, position)
    raise "Child already added" if @childrenHash.has_key?(child.name)

    @childrenHash[child.name]  = child
    @children = @children.insert(position, child)
    child.parent = self
    return child

  end

  def add_last(child)
    raise "Child already added" if @childrenHash.has_key?(child.name)

    @childrenHash[child.name]  = child
    @children <<  child
    @last_items_count += 1
    child.parent = self
    return child

  end

  # Adds the specified child node to the receiver node.  The child node's
  # parent is set to be the receiver.  The child is added as the last child in
  # the current list of children for the receiver node.
  def add(child)
    raise "Child already added" if @childrenHash.has_key?(child.name)

    @childrenHash[child.name]  = child
    position = @children.size - @last_items_count
    @children.insert(position, child)
    child.parent = self
    return child

  end

  # Wrapp remove! making sure to decrement the last_items counter if
  # the removed child was a last item
  def remove!(child)
    @last_items_count -= +1 if child && child.last
    super
  end


  # Will return the position (zero-based) of the current child in
  # it's parent
  def position
    self.parent.children.index(self)
  end
end