module ActionDispatch
  module Http
    module Parameters
      PARAMETERS_KEY = 'action_dispatch.request.path_parameters'

      DEFAULT_PARSERS = {
        Mime[:json] => lambda { |raw_post|
          data = ActiveSupport::JSON.decode(raw_post)
          data.is_a?(Hash) ? data : {:_json => data}
        }
      }

      def self.included(klass)
        class << klass
          attr_accessor :parameter_parsers
        end

        klass.parameter_parsers = DEFAULT_PARSERS
      end
      # Returns both GET and POST \parameters in a single hash.
      def parameters
        params = get_header("action_dispatch.request.parameters")
        return params if params

        params = begin
                   request_parameters.merge(query_parameters)
                 rescue EOFError
                   query_parameters.dup
                 end
        params.merge!(path_parameters)
        set_header("action_dispatch.request.parameters", params)
        params
      end
      alias :params :parameters

      def path_parameters=(parameters) #:nodoc:
        delete_header('action_dispatch.request.parameters')
        set_header PARAMETERS_KEY, parameters
      end

      # Returns a hash with the \parameters used to form the \path of the request.
      # Returned hash keys are strings:
      #
      #   {'action' => 'my_action', 'controller' => 'my_controller'}
      def path_parameters
        get_header(PARAMETERS_KEY) || {}
      end

      private

      def parse_formatted_parameters(parsers)
        return yield if content_length.zero?

        strategy = parsers.fetch(content_mime_type) { return yield }

        begin
          strategy.call(raw_post)
        rescue => e # JSON or Ruby code block errors
          my_logger = logger || ActiveSupport::Logger.new($stderr)
          my_logger.debug "Error occurred while parsing request parameters.\nContents:\n\n#{raw_post}"

          raise ParamsParser::ParseError.new(e.message, e)
        end
      end

      def params_parsers
        ActionDispatch::Request.parameter_parsers
      end
    end
  end
end