Valid Binary Search Trees

binary_search_tree.rb

module BinarySearchTree
  class Node
   
   include Comparable
   attr_reader :value
   attr_accessor :left, :right, :nodes_tracker

   def initialize(value)
     @value = value
     self.nodes_tracker = []
    end

    def insert_node(node)
      self.value <=> node.value
      if node.value < self.value
        self.left =  node
        self.nodes_tracker = node
      elsif node.value > self.value
        self.right = node
        self.nodes_tracker = node
      else
        false
      end   
    end

    def node_checker
      if (@tree.left.value < self.value ) && (@tree.right.value > self.value) && ( (@tree.left.left != nil) || (@tree.right.right != nil) )
        puts "YES"
      else
        puts "N0"
      end
    end

    def valid?(tree)
     @tree = tree
      return "NO" if (tree == nil)
      return "NO" if (@tree.left == nil) && (@tree.right == nil)
      
      if (@tree.left != nil ) && (@tree.right != nil)
        node_checker
      else
        puts "N0"
      end
    end    

    def validate_tree?(root_tree)
      if !root_tree.nodes_tracker.empty?
        root_tree.nodes_tracker.each {|tree| tree.valid?(tree) }
      else
        root_tree.valid?(self)
      end
    end
   
  end 

end