class ActiveModel::Serializers::Xml::Serializer

def add_attributes_and_methods
  (serializable_attributes + serializable_methods).each do |attribute|
    key = ActiveSupport::XmlMini.rename_key(attribute.name, options)
    ActiveSupport::XmlMini.to_tag(key, attribute.value,
      options.merge(attribute.decorations))
  end
end

def add_extra_behavior
end

def add_procs
  if procs = options.delete(:procs)
    Array.wrap(procs).each do |proc|
      if proc.arity == 1
        proc.call(options)
      else
        proc.call(options, @serializable)
      end
    end
  end
end

def attributes_hash
  attributes = @serializable.attributes
  if options[:only].any?
    attributes.slice(*options[:only])
  elsif options[:except].any?
    attributes.except(*options[:except])
  else
    attributes
  end
end

def initialize(serializable, options = nil)
  @serializable = serializable
  @options = options ? options.dup : {}
  @options[:only] = Array.wrap(@options[:only]).map { |n| n.to_s }
  @options[:except] = Array.wrap(@options[:except]).map { |n| n.to_s }
end

def serializable_attributes
  attributes_hash.map do |name, value|
    self.class::Attribute.new(name, @serializable, value)
  end
end

def serializable_methods
  Array.wrap(options[:methods]).inject([]) do |methods, name|
    methods << self.class::MethodAttribute.new(name.to_s, @serializable) if @serializable.respond_to?(name.to_s)
    methods
  end
end

def serialize
  require 'builder' unless defined? ::Builder
  options[:indent]  ||= 2
  options[:builder] ||= ::Builder::XmlMarkup.new(:indent => options[:indent])
  @builder = options[:builder]
  @builder.instruct! unless options[:skip_instruct]
  root = (options[:root] || @serializable.class.model_name.element).to_s
  root = ActiveSupport::XmlMini.rename_key(root, options)
  args = [root]
  args << {:xmlns => options[:namespace]} if options[:namespace]
  args << {:type => options[:type]} if options[:type] && !options[:skip_types]
  @builder.tag!(*args) do
    add_attributes_and_methods
    add_extra_behavior
    add_procs
    yield @builder if block_given?
  end
end