module Elastics
  class Result
    module RailsHelper

      module Highlighter

        RE = /highlighted_(\w+)/

        def respond_to?(meth, private=false)
          meth.to_s =~ RE
          !!$1 || super
        end

        def method_missing(meth, *args, &block)
          meth.to_s =~ RE
          attribute = $1
          attribute ? higlighted(attribute, args.first || {}) : super
        end

        # TODO: add the doc for this method
        def higlighted(attribute, opts={})
          opts = { :fragment_separator => ' ... ' }.merge(opts)
          if self['highlight']
            # works also with nested attributes
            key, high = self['highlight'].find { |k, v| k.gsub('.', '_') == attribute }
            high      = Array.wrap(high) if high
          end
          if high.blank?
            respond_to?(attribute.to_sym) ? send(attribute.to_sym) : ''
          else
            high.join(opts[:fragment_separator]).html_safe
          end
        end

      end

      # extend if result is a Search or MultiGet
      def self.should_extend?(result)
        result.is_a?(Search) || result.is_a?(MultiGet)
      end

      # extend the collection on extend
      def self.extended(result)
        result.collection.each { |h| h.extend(Highlighter) }
      end

    end
  end
end