extended_content.rb

    def replace_value_for(extended_field_element_name, value, field = nil)

      logger.debug("what is extended_content: " + self.extended_content.inspect)
      # Fetch the existing data from XML
      sandpit_data = structured_extended_content

      logger.debug("what is sandpit_data: " + sandpit_data.inspect)
      # Replace the value we're changing
      # The value needs to be nested to form an array if necessary, since we ALWAYS pass in an array.
      if field.is_a_choice? && !value.is_a?(Array)
        value = [[value]]
      elsif (field.is_a_choice? && !value.first.is_a?(Array)) || !value.is_a?(Array)
        value = [value]
      end

      # if field is a choice and users may add new choices
      # and value contains something that isn't current found as a choice, create a corresponding choice
      if field.is_a_choice?
        # peel off the array nesting
        # to get to nested values
        value.flatten.each do |v|

          # TODO: this has been copied and modified from extended_content_helpers, DRY up
          # one difference is that this assumes no parent
          # since we flatten

          # splits a value into label and value
          # if it has a pattern of "label (value)"
          # useful for auto populated pseudo choices (all topic types available as choices)
          # where label may not be unique
          # and case where user may contribute a new choice
          parts = v.match(/(.+)\(([^\(\)]+)\)\Z/).to_a
          # l is label for this particular value
          l = nil
          unless parts.blank?
            l = parts[1].chomp(' ')
            v = parts[2]
          end

          matching_choice = Choice.matching(l,v)

          # Handle the creation of new choices where the choice is not recognised.
          if !matching_choice && %w(autocomplete choice).include?(field.ftype) && field.user_choice_addition?
            parent = Choice.find(1)

            begin
              choice = Choice.create!(:value => v, :label => l)
              choice.move_to_child_of(parent)
              choice.save!
              field.choices << choice
              field.save!
            rescue
              next
            end
          end
        end
      end

      sandpit_data[extended_field_element_name] = value

      # Write the data back to XML
      self.structured_extended_content = sandpit_data

      logger.debug("what is extended_content: " + self.extended_content.inspect)
      logger.debug("what is value: " + value.inspect)
      value
    end