module Internals

  # FIXME Merge into Base, extract common with Indexed::Base.
  #
  module Indexing # :nodoc:all
    # A Bundle is a number of indexes
    # per [index, category] combination.
    #
    # At most, there are three indexes:
    # * *core* index (always used)
    # * *weights* index (always used)
    # * *similarity* index (used with similarity)
    # 
    # In Picky, indexing is separated from the index
    # handling itself through a parallel structure.
    #
    # Both use methods provided by this base class, but
    # have very different goals:
    #
    # * *Indexing*::*Bundle* is just concerned with creating index files
    #   and providing helper functions to e.g. check the indexes.
    #
    # * *Index*::*Bundle* is concerned with loading these index files into
    #   memory and looking up search data as fast as possible.
    #
    module Bundle
    
      class SuperBase
    
        attr_reader   :identifier, :files
        attr_accessor :index, :weights, :similarity, :configuration, :similarity_strategy
    
        delegate :clear,    :to => :index
        delegate :[], :[]=, :to => :configuration
    
        def initialize name, configuration, similarity_strategy
          @identifier = "#{configuration.identifier}:#{name}"
          @files      = Internals::Index::Files.new name, configuration
      
          @index         = {}
          @weights       = {}
          @similarity    = {}
          @configuration = {} # A hash with config options.
      
          @similarity_strategy = similarity_strategy
        end
    
        # Get a list of similar texts.
        #
        # Note: Does not return itself.
        #
        def similar text
          code = similarity_strategy.encoded text
          similar_codes = code && @similarity[code]
          similar_codes.delete text if similar_codes
          similar_codes || []
        end
    
      end
    
    end
  
  end
  
end