module Eitil
  module ControllerDecorator
    extend ActiveSupport::Concern 
    included do

      private

      def decorate(dec_item, dec_method: nil, dec_class: nil, **dec_kwargs)
        all_args_to_ivars binding
        set_ivars :dec_class, :dec_method, :decorator
        send_to_decorator
      end

      def send_to_decorator
        @dec_kwargs.any? ? @decorator.send(@dec_method, @dec_item, @dec_kwargs)
                         : @decorator.send(@dec_method, @dec_item)
       
        rescue NoMethodError => e       
          inform_no_method_for_decorator_error
          @dec_item
      end

      def inform_no_method_for_decorator_error
        message = "Warning: NoMethodError for #{@dec_class}.#{@dec_method}, returned @dec_item instead."
        Logger.new("#{Rails.root}/log/decorator_log.log").warn message
        warn message
      end

      def set_dec_method
        @dec_method = @dec_method || derived_dec_method || :base
      end

      def derived_dec_method
        return unless respond_to? :params
        return :app if params["isMobile"]
        return :web if params["isWeb"]
      end

      def set_dec_class
        @dec_class = @dec_class ? manual_set_dec_class : derived_dec_class
      end

      def manual_set_dec_class
        "#{@dec_class}Decorator".constantize
      end

      def derived_dec_class
        "#{@dec_item.class.name}Decorator".constantize
      end

      def set_decorator
        @decorator = @dec_class.new controller_ivars
      end

      def controller_ivars
        eval(Eitil.get_controller_ivars_method).map do |ivar|
          { ivar => instance_variable_get("@#{ivar.to_s}") }
        end.inject &:merge
      end

    end
  end
end