plugin_init.rb

# plugins/local/public/plugin_init.rb
Rails.application.config.after_initialize do 

    SearchController.class_eval do

        private

          def set_search_criteria
            
            @criteria = params.select{|k,v|
              ["page", "q", "type", "sort",
               "filter_term", "root_record", "format"].include?(k) and not v.blank?
            }
            
            @criteria["page"] ||= 1
            @criteria["sort"] = "title_sort asc" unless @criteria["sort"] or @criteria["q"] or params["advanced"].present?

            if @criteria["filter_term"]
              @criteria["filter_term[]"] = Array(@criteria["filter_term"]).reject{|v| v.blank?}.map { |ft|  ActionController::Base.helpers.sanitize(ft) }
              @criteria.delete("filter_term")
            end

            if params[:type].blank?
              @criteria['type[]'] = SearchController::DETAIL_TYPES
            else
              @criteria['type[]'] = Array(params[:type]).keep_if {|t| SearchController::VIEWABLE_TYPES.include?(t)}
              @criteria.delete("type")
            end

            @criteria['exclude[]'] = params[:exclude] if not params[:exclude].blank?
            @criteria['facet[]'] = SearchController::FACETS
 
            
          end
          
      end 
        
end