First steps to watch functionality

Author: gazay

lib/gon.rb

@@ -5,6 +5,7 @@
 require 'action_controller'
 require 'gon/base'
 require 'gon/global'
+require 'gon/watch'
 require 'gon/request'
 require 'gon/helpers'
 require 'gon/escaper'
@@ -22,6 +23,10 @@ def global
       Gon::Global
     end
 
+    def watch
+      Gon::Watch
+    end
+
     def method_missing(method, *args, &block)
       if ( method.to_s =~ /=$/ )
         if public_method_name? method
@@ -65,7 +70,12 @@ def get_variable(name)
     end
 
     def set_variable(name, value)
-      Request.gon[name] = value
+      if Gon::Watch.need_return?
+        Gon::Watch.clear
+        Gon::Watch.return_variable(value)
+      else
+        Request.gon[name] = value
+      end
     end
 
     def store_builder_data(builder, data, options)

lib/gon/base.rb

@@ -24,7 +24,7 @@ def render_data(options)
         script.html_safe
       end
 
-      def get_controller(options)
+      def get_controller(options = {})
         options[:controller] ||
           Gon::Request.env['action_controller.instance'] ||
           Gon::Request.env['action_controller.rescue.response'].

lib/gon/watch.rb

@@ -0,0 +1,38 @@
+module Gon
+  class Watch
+    class << self
+
+      def method_missing(method, *args, &block)
+        @return = return_variable?(method)
+        Gon.send method, *args, &block
+      end
+
+      def clear
+        @return = false
+      end
+
+      def need_return?
+        defined?(@return) and @return
+      end
+
+      def return_variable(value)
+        controller = Gon::Base.get_controller
+
+        controller.render :json => value
+      end
+
+      private
+
+      def return_variable?(variable)
+        controller = Gon::Base.get_controller
+        params = controller.params
+        variable = variable.to_s.gsub('=', '')
+
+        controller.request.xhr? &&
+          params[:gon_return_variable] &&
+          params[:gon_watched_variable] == variable
+      end
+
+    end
+  end
+end