Contents

require 'nokogiri'
require 'nice/logic'

module Nice
  class Middleware
    
    ## case 1: this is the first call of the component -> no previous state
		
		# => 	remove elements not belonging to the start state, generate UID for reference
		#		nodes ({ref_element}_ref) and respond with HTML
		
		## case 2: this is an ordinary call of another state
		
		# => 	respond with JS with assignments to remove elements not included
		#		in current state and assignments to insert elements of current state.
		
		
		## case 3: curr_state == prev_state 
		
		# => 	respond with JS which either first removes all elements of the current state and
		#		later inserts new content OR directly replaces elements
		
    
    def initialize(app)
      @app = app
    end
  
    def call(env)
      @doc = nil
      @referer = nil

      status, @headers, @body = @app.call(env)
      
      if html? || js?
      	 @referer = env["HTTP_REFERER"]
      	 @method = env["REQUEST_METHOD"]
      	 @path = env["PATH_INFO"]

      	 # in case 2+3 the response will be plain javascript
      	 if @referer
      	 	@headers = {"Content-Type" => "text/javascript"}
      	 end

        [status, @headers, self]
      else
        [status, @headers, @body]
      end
    end
    
    def each(&block)
      if html? || js?
        block.call("<!-- previous state: #{@referer} -->\n")
        block.call( Nice::Logic.run( @method, @path, @referer, doc ) )
      else
        block.call(@body)
      end
    end
    
    # Helper
    private 
    
    def html?
      @headers["Content-Type"] && @headers["Content-Type"].include?("text/html")
    end
    
    def js?
      @headers["Content-Type"] && @headers["Content-Type"].include?("text/javascript")
    end

    def doc
      @doc ||= Nokogiri::HTML(body_to_string)
    end
  
    def body_to_string
      s = ""
      @body.each { |x| s << x }
      s
    end
    
    def update_content_length
      @headers['Content-Length'] = Rack::Utils.bytesize(@body).to_s
    end    
  end
end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
nice-0.0.2	lib/nice/middleware.rb