# This class manages creation of aliases.
module Alias
  class Manager
  
    def initialize #:nodoc:
      @alias_creators = {}
      @verbose = false
      @force = false
    end

    attr_accessor :alias_creators, :verbose, :force, :indexed_aliases
    def alias_types; @alias_creators.keys; end
    def alias_creator_objects; @alias_creators.values; end
    def alias_map(type)
      @alias_creators[type] && @alias_creators[type].alias_map
    end
    
    def create_creator(alias_type)
      creator_class_string = "Alias::#{alias_type.camelize}Creator"
      if creator_class = Object.any_const_get(creator_class_string)
        creator_class.new
      else
        puts "Creator class '#{creator_class_string}' not found." if @verbose
        nil
      end
      
    end
    
    def create_aliases(alias_type, aliases_hash)
      if (obj = @alias_creators[alias_type.to_sym] ||= create_creator(alias_type.to_s))
        aliases_hash = aliases_hash.dup
        create_options = aliases_hash.slice_off!('auto_alias', 'verbose', 'force')
        create_options['verbose'] = @verbose unless create_options.has_key?('verbose')
        obj.manager_create(aliases_hash, create_options)        
      end
    end
    
    def search(search_hash)
      result = nil
      search_hash.each do |k,v|
        new_result = simple_search(k,v)
        #AND's searches
        result = intersection_of_two_arrays(new_result, result)
      end
      #duplicate results in case they are modified
      result = result.map {|e| e.dup} if result
      alias_creator_objects.each {|e| e.searched_at = Time.now }
      result
    end
    
    def list
      indexed_aliases.map {|e| e.dup}
    end
    
    def simple_search(field, search_term)
      result = indexed_aliases.select {|e| 
        search_term.is_a?(Regexp) ? e[field] =~ search_term : e[field] == search_term
      }
      result
    end
    
    def intersection_of_two_arrays(arr1, arr2)
      arr2.nil? ? arr1 : arr1.select {|e| arr2.include?(e)}
    end
    
    def indexed_aliases(reindex=true)
      reindex ? @indexed_aliases = reindex_aliases(@indexed_aliases) : @indexed_aliases
    end
        
    def reindex_aliases(searchable_array=nil)
      searchable_array ||= []
      @alias_creators.map do |type, creator|
        if creator.modified_since_last_search?
          searchable_array.delete_if {|e| e[:type] == type.to_s}
          new_arr = creator.to_searchable_array.each {|e| e[:type] = type.to_s}
          searchable_array += new_arr
        end
      end
      searchable_array
    end
  end
end