class Grape::Middleware::Base

def after; end

def before; end

def call(env)
  dup.call!(env).to_a
end

def call!(env)
  @env = env
  before
  begin
    @app_response = @app.call(@env)
  ensure
    begin
      after_response = after
    rescue StandardError => e
      warn "caught error of type #{e.class} in after callback inside #{self.class.name} : #{e.message}"
      raise e
    end
  end
  response = after_response || @app_response
  merge_headers response
  response
end

def content_type
  content_type_for(env[Grape::Env::API_FORMAT] || options[:format]) || TEXT_HTML
end

def content_type_for(format)
  content_types_indifferent_access[format]
end

def content_types
  @content_types ||= Grape::ContentTypes.content_types_for(options[:content_types])
end

def content_types_indifferent_access
  @content_types_indifferent_access ||= content_types.with_indifferent_access
end

def default_options
  {}
end

def initialize(app, *options)
  @app = app
  @options = options.any? ? default_options.deep_merge(options.shift) : default_options
  @app_response = nil
end

def merge_headers(response)
  return unless headers.is_a?(Hash)
  case response
  when Rack::Response then response.headers.merge!(headers)
  when Array          then response[1].merge!(headers)
  end
end

def mime_types
  @mime_types ||= Grape::ContentTypes.mime_types_for(content_types)
end

def response
  return @app_response if @app_response.is_a?(Rack::Response)
  @app_response = Rack::Response.new(@app_response[2], @app_response[0], @app_response[1])
end