# encoding: utf-8
module Mongoid::Search::Util
  def self.keywords(klass, fields)
    if fields.is_a?(Array)
      fields.map do |field|
        self.keywords(klass, field)
      end
    elsif fields.is_a?(Hash)
      fields.keys.map do |field|
        attribute = klass.send(field)
        unless attribute.blank?
          if attribute.is_a?(Array)
            attribute.map{ |a| self.keywords(a, fields[field]) }
          else
            self.keywords(attribute, fields[field])
          end
        end
      end
    else
      value = if klass.respond_to?(fields.to_s + "_translations")
                klass.send(fields.to_s + "_translations").values
              elsif klass.respond_to?(fields)
                klass.send(fields)
              else
                value = klass[fields];
              end
      value = value.join(' ') if value.respond_to?(:join)
      normalize_keywords(value) if value
    end
  end

  def self.normalize_keywords(text)
    ligatures     = Mongoid::Search.ligatures
    ignore_list   = Mongoid::Search.ignore_list
    stem_keywords = Mongoid::Search.stem_keywords
    stem_proc     = Mongoid::Search.stem_proc

    return [] if text.blank?
    text = text.to_s.
      mb_chars.
      normalize(:kd).
      downcase.
      to_s.
      gsub(/[._:;'"`,?|+={}()!@#%^&*<>~\$\-\\\/\[\]]/, ' '). # strip punctuation
      gsub(/[^\s\p{Alnum}]/,'').   # strip accents
      gsub(/[#{ligatures.keys.join("")}]/) {|c| ligatures[c]}.
      split(' ').
      reject { |word| word.size < Mongoid::Search.minimum_word_size }
    text = text.reject { |word| ignore_list.include?(word) } unless ignore_list.blank?
    text = text.map(&stem_proc) if stem_keywords
    text
  end

end