module SearchMethods
  def depth(n)
    if @payload == n
      return self
    else
      @children.each do |child|
        node = child.depth(n)
        return node unless node.nil?
      end # do child end
      return nil
    end # if payload end
  end # def depth end

  def breadth(n)
    @queue = []
    @queue << self
    current_node = @queue.shift
    next_nodes = @queue.push(current_node.children)

    while !@queue.empty?

      puts "initial current node"
      p current_node # this is a tree of trees/arrays
      puts @payload unless self.nil?
      # puts current_node.children
      if current_node.payload == n
        return current_node
      else
        next_nodes = @queue.push(current_node.children)
        puts "should equal initial current node"
        p current_node # this is still a tree of trees/arrays

        current_node = @queue.shift
        puts "shifted node - should equal the 'initial current
           mode' that appears next"
        p current_node # and now it is an array of trees/ arrays
        # because it is an array, I can no longer specify
        # current_node.children (cause obvs, children isn't a
        # method) and cannot move on to the next step.
        # How do I escape this array?

      end # if payload end
      # return nil
    end # while loop end
  end # def breadth end
end # module end

class Tree
  attr_accessor :payload, :children
  include SearchMethods

  def initialize(payload, children)
    @payload = payload
    @children = children
  end
end


# The "Leafs" of a tree, elements that have no children
deep_fifth_node = Tree.new(5, [])
eleventh_node = Tree.new(11, [])
fourth_node   = Tree.new(4, [])

# The "Branches" of the tree
ninth_node = Tree.new(9, [fourth_node])
sixth_node = Tree.new(6, [deep_fifth_node, eleventh_node])
seventh_node = Tree.new(7, [sixth_node])
shallow_fifth_node = Tree.new(5, [ninth_node])

# The "Trunk" of the tree
trunk   = Tree.new(2, [seventh_node, shallow_fifth_node])

p trunk.breadth(5)