cvut/kosapi_client.rb

module KOSapiClient
  class RequestBuilderDelegator

    def initialize(request_builder)
      @request_builder = request_builder
      @response = nil
    end

    alias :super_method_missing :method_missing

    def respond_to_missing?(method, include_all)
      if @response
        @response.respond_to?(method, include_all)
      else
        @request_builder.respond_to?(method, include_all)
      end
    end

    if RUBY_VERSION >= '3.0'
      def method_missing(method, *args, **kwargs, &block)
        if @response
          delegate_to_response(method, *args, **kwargs, &block)
        else
          delegate_to_builder(method, *args, **kwargs, &block)
        end
      end

      private

      def delegate_to_response(method, *args, **kwargs, &block)
        if @response.respond_to?(method)
          @response.send(method, *args, **kwargs, &block)
        else
          super_method_missing(method, *args, **kwargs)
        end
      end

      def delegate_to_builder(method, *args, **kwargs, &block)
        if @request_builder.respond_to?(method)
          res = @request_builder.send(method, *args, **kwargs, &block)
          if res.equal?(@request_builder)
            self
          else
            res
          end
        else
          @request_builder.finalize
          @response = @request_builder.response
          delegate_to_response(method, *args, **kwargs, &block)
        end
      end

    else # RUBY_VERSION < '3.0'
      def method_missing(method, *args, &block)
        if @response
          delegate_to_response(method, *args, &block)
        else
          delegate_to_builder(method, *args, &block)
        end
      end

      private

      def delegate_to_response(method, *args, &block)
        if @response.respond_to?(method)
          @response.send(method, *args, &block)
        else
          super_method_missing(method, *args)
        end
      end

      def delegate_to_builder(method, *args, &block)
        if @request_builder.respond_to?(method)
          res = @request_builder.send(method, *args, &block)
          if res.equal?(@request_builder)
            self
          else
            res
          end
        else
          @request_builder.finalize
          @response = @request_builder.response
          delegate_to_response(method, *args, &block)
        end
      end
    end

  end
end