class Sass::Tree::Node

def self.inherited(base)
  node_name = base.name.gsub(/.*::(.*?)Node$/, '\\1').downcase
  base.instance_eval <<-METHODS
    # @return [Symbol] The name that is used for this node when visiting.
    def node_name
      :#{node_name}
    end
    # @return [Symbol] The method that is used on the visitor to visit nodes of this type.
    def visit_method
      :visit_#{node_name}
    end
    # @return [Symbol] The method name that determines if the parent is invalid.
    def invalid_child_method_name
      :"invalid_#{node_name}_child?"
    end
    # @return [Symbol] The method name that determines if the node is an invalid parent.
    def invalid_parent_method_name
      :"invalid_#{node_name}_parent?"
    end
  METHODS
end

def <<(child)
  return if child.nil?
  if child.is_a?(Array)
    child.each {|c| self << c}
  else
    self.has_children = true
    @children << child
  end
end

def ==(other)
  self.class == other.class && other.children == children
end

def balance(*args)
  res = Sass::Shared.balance(*args)
  return res if res
  raise Sass::SyntaxError.new("Unbalanced brackets.", :line => line)
end

def bubbles?
  false
end

def children=(children)
  self.has_children ||= !children.empty?
  @children = children
end

def css
  Sass::Tree::Visitors::ToCss.new.visit(self)
end

def css_with_sourcemap
  visitor = Sass::Tree::Visitors::ToCss.new(:build_source_mapping)
  result = visitor.visit(self)
  return result, visitor.source_mapping
end

def deep_copy
  Sass::Tree::Visitors::DeepCopy.visit(self)
end

def each
  yield self
  children.each {|c| c.each {|n| yield n}}
end

def filename
  @filename || (@options && @options[:filename])
end

def initialize
  @children = []
  @filename = nil
  @options = nil
end

def inspect
  return self.class.to_s unless has_children
  "(#{self.class} #{children.map {|c| c.inspect}.join(' ')})"
end

def invisible?; false; end

def options=(options)
  Sass::Tree::Visitors::SetOptions.visit(self, options)
end

def style
  @options[:style]
end

def to_sass(options = {})
  Sass::Tree::Visitors::Convert.visit(self, options, :sass)
end

def to_scss(options = {})
  Sass::Tree::Visitors::Convert.visit(self, options, :scss)
end