# second_level_cache_fix.rb
# Oleg Andreev <oleganza@gmail.com>
# November 3, 2008

module DataMapper
  class Repository
    module SecondLevelCacheFix

      # quick install
      def self.install
        DataMapper::Repository.send(:include, self)
      end

      # more flexible install using Repository.send(:include, SecondLevelCacheFix)
      def self.included(repo_cls)
        DataMapper::Model.extend(SLCModel)
        DataMapper::Model.append_extensions(SLCModel)
      end

      # ask model for a second_level_cache
      def identity_map(model)
        @identity_maps[model] ||= IdentityMap.new(model.second_level_cache)
      end

      module SLCModel
        attr_accessor :second_level_cache
        def second_level_cache
          @second_level_cache ||=
            (self == DataMapper::Model ? nil : DataMapper::Model.second_level_cache)
        end
      end

    end # SecondLevelCacheFix
  end # Repository
end # DM