require 'puppet/interface/option'

class Puppet::Interface::OptionBuilder
  attr_reader :option

  def self.build(face, *declaration, &block)
    new(face, *declaration, &block).option
  end

  private
  def initialize(face, *declaration, &block)
    @face   = face
    @option = Puppet::Interface::Option.new(face, *declaration)
    block and instance_eval(&block)
    @option
  end

  # Metaprogram the simple DSL from the option class.
  Puppet::Interface::Option.instance_methods.grep(/=$/).each do |setter|
    next if setter =~ /^=/
    dsl = setter.sub(/=$/, '')

    unless self.class.methods.include?(dsl)
      define_method(dsl) do |value| @option.send(setter, value) end
    end
  end

  # Override some methods that deal in blocks, not objects.
  def before_action(&block)
    block or raise ArgumentError, "#{@option} before_action requires a block"
    if @option.before_action
      raise ArgumentError, "#{@option} already has a before_action set"
    end
    unless block.arity == 3 then
      raise ArgumentError, "before_action takes three arguments, action, args, and options"
    end
    @option.before_action = block
  end

  def after_action(&block)
    block or raise ArgumentError, "#{@option} after_action requires a block"
    if @option.after_action
      raise ArgumentError, "#{@option} already has a after_action set"
    end
    unless block.arity == 3 then
      raise ArgumentError, "after_action takes three arguments, action, args, and options"
    end
    @option.after_action = block
  end
end