class Product < ActiveRecord::Base

  has_many :build_rules

  # <tt>incompatible_products</tt> will return an array of products that
  # are not compatible with the current product.
  def incompatible_products
    products = []

    build_rules.each do |rule|
      products << rule.root.product if rule.root && rule.root != rule
      products << rule.children.map(&:product)
    end

    products.flatten
  end

  # <tt>incompatible_product?</tt> returns true or false depending on
  # whether the product passed is a compatible product or not.
  #   ex.
  #   <%= @product.incompatible_product?(@incompatible_product) %> # => true
  def incompatible_product?(product)
    incompatible_products.include?(product)
  end

end