class Nokogiri::XML::Builder::NodeBuilder

def [] k
  @node[k]
end

def []= k, v
  @node[k] = v
end

def initialize node, doc_builder
  @node = node
  @doc_builder = doc_builder
end

def method_missing(method, *args, &block)
  opts = args.last.is_a?(Hash) ? args.pop : {}
  case method.to_s
  when /^(.*)!$/
    @node['id'] = $1
    @node.content = args.first if args.first
  when /^(.*)=/
    @node[$1] = args.first
  else
    @node['class'] =
      ((@node['class'] || '').split(/\s/) + [method.to_s]).join(' ')
    @node.content = args.first if args.first
  end
  # Assign any extra options
  opts.each do |k,v|
    @node[k.to_s] = ((@node[k.to_s] || '').split(/\s/) + [v]).join(' ')
  end
  if block_given?
    old_parent = @doc_builder.parent
    @doc_builder.parent = @node
    value = @doc_builder.instance_eval(&block)
    @doc_builder.parent = old_parent
    return value
  end
  self
end