config.after_initialize do
  class ::ActionController::Base
    alias_method :original_render, :render
    def render(*args, &block)
      if args.length == 1 && args[0].kind_of?(Hash)
        hash = args.first 
        case hash[:rgviz]
        when nil then original_render *args, &block
        else
          model = hash[:rgviz]
          conditions = hash[:conditions]
          query = params[:tq]
          tqx = params[:tqx] || ''
          pieces = tqx.split ';'
          reqId = '0'
          version = '0.6'
          responseHandler = 'google.visualization.Query.setResponse'
          out = 'json'
          pieces.each do |p|
            key_value = p.split ':'
            if key_value.length == 2
              case key_value[0]
              when 'reqId'
                reqId = key_value[1]
              when 'version'
                version = key_value[1]
              when 'responseHandler'
                responseHandler = key_value[1]
              when 'out'
                out = key_value[1]
              end
            end
          end
          
          begin
            executor = Rgviz::Executor.new model, Rgviz::Parser.new(query).parse
            options = {}
            options[:conditions] = conditions if conditions
            table = executor.execute options
            
            if out == 'json'
              original_render :text => "#{responseHandler}({reqId:'#{reqId}',status:'ok',version:'#{version}',table:#{table.to_json}});"
            elsif out == 'html'
              original_render :text => Rgviz::HtmlRenderer.render(table)
            else
              original_render :text => "#{responseHandler}({reqId:'#{reqId}',status:'error',version:'#{version}',errors:[{reason:'not_supported', message:'Unsupported output type: #{out}'}]});"
            end
          rescue ParseException => e
            msg = e.message.gsub("'", "\\'")
            
            if out == 'json'
              original_render :text => "#{responseHandler}({reqId:'#{reqId}',status:'error',version:'#{version}',errors:[{reason:'invalid_query', message:'#{msg}'}]});"
            elsif out == 'html'
              original_render :text => "<b>Error:</b> #{msg}"
            else
              original_render :text => "<b>Unsupported output type:</b> #{out}"
            end
          end
        end
      else
        original_render *args, &block
      end
    end
  end
end