gistfile1.builder

module CustomSearch
  mattr_accessor :registered_classes

  def self.search(qstring)
    results = {}
    self.registered_classes.each do |klass|
      results[klass.name] = klass.on_index(qstring)
    end
    results
  end

  def self.included(base)
    base.send :include, InstanceMethods
    base.send :extend, ClassMethods
  end

  module ClassMethods
    def use_as_index(*columns)
      CustomSearch.registered_classes ||= []
      CustomSearch.registered_classes << self unless CustomSearch.registered_classes.include?(self) # nesse caso, self vai ser a classe, nao a instancia
      
      @search_columns = columns
      self.send :named_scope, :on_index, proc { |text| {:conditions => ["lower(search_index) like lower(?)", "%#{text}%"]} }
      self.send :before_save, :update_index
    end

    def search_columns
      @search_columns ||= []
    end
    
    def rebuild_indices
      find(:all).each do |obj|
        obj.send :update_index
        obj.save
      end
    end
  end

  module InstanceMethods
    def update_index
      self.search_index = self.class.search_columns.map{ |col| send(col) }.join(" ").chomp
    end
    protected :update_index
  end
end
ActiveRecord::Base.send :include, CustomSearch