module Doorkeeper::Config::Option

def self.extended(base) 

def self.extended(base)
  return if base.respond_to?(:builder_class)
  raise Doorkeeper::MissingConfigurationBuilderClass, "Define `self.builder_class` method " \
                    "for #{base} that returns your custom Builder class to use options DSL!"
end

def option(name, options = {})


option :scopes builder_class: ScopesBuilder
option :name, default: 'My Name'
option :name, as: :set_name
option :name

==== Examples

* [+:builder_class+] Configuration option builder class
* [+:default+] The default value in case no option was set
* [:+as+] Set the builder method that goes inside +configure+ block

==== Options

that returns the value of the config attribute.
Builder should take a block as the initializer parameter and respond to function +build+
define +builder_class+ parameter.
If you want to introduce another level of config DSL you can

option while the config attribute will be the +name+ parameter.
If the +:as+ option is defined, the builder method will be the specified
The +name+ parameter will set both builder method and config attribute.

+Builder+ class.
in the +Config+ class and the other method will take place in the
When you call option, it defines two methods. One method will take place

Defines configuration option 
def option(name, options = {})
  attribute = options[:as] || name
  attribute_builder = options[:builder_class]
  builder_class.instance_eval do
    if method_defined?(name)
      Kernel.warn "[DOORKEEPER] Option #{name} already defined and will be overridden"
      remove_method name
    end
    define_method name do |*args, &block|
      if (deprecation_opts = options[:deprecated])
        warning = "[DOORKEEPER] #{name} has been deprecated and will soon be removed"
        warning = "#{warning}\n#{deprecation_opts.fetch(:message)}" if deprecation_opts.is_a?(Hash)
        Kernel.warn(warning)
      end
      value = if attribute_builder
                attribute_builder.new(&block).build
              else
                block || args.first
              end
      @config.instance_variable_set(:"@#{attribute}", value)
    end
  end
  define_method attribute do |*_args|
    if instance_variable_defined?(:"@#{attribute}")
      instance_variable_get(:"@#{attribute}")
    else
      options[:default]
    end
  end
  public attribute
end