# approximatesearch.rb  -  "approximate search library"
#  
#   Copyright (c) 2010  Kiyoka Nishiyama  <kiyoka@sumibi.org>
#   
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#  $Id: 
#
require 'distributedtrie'
require 'sekka/kvs'

class ApproximateSearch
  def initialize( jarow_shikii )
    @jarow_shikii = jarow_shikii
  end

  def search( userid, kvs, keyword, type )
    arr = []
    case userid
    when "M"
      arr  = searchByUser( "M", kvs, keyword, type )
    else
      h = {}
      searchByUser( "M", kvs, keyword, type ).each { |item| h[ item[1] ] = item[0] }
      searchByUser(  userid,  kvs, keyword, type ).each { |item| h[ item[1] ] = item[0] }
      h.keys.each { |k|  arr << [ h[k], k ] }
    end
    arr.sort_by {|item| [1.0 - item[0], item[1]]}
  end

  def searchByUser( userid, kvs, keyword, type )
    pair = case type
           when 'k' # okuri nashi kanji entry
             ["Ik:" + userid + ":", keyword.downcase]
           when 'K' # okuri ari   kanji entry
             ["IK:" + userid + ":", keyword]
           when 'h' # hiragana phrase entry
             ["Ih:" + userid + ":", keyword.downcase]
           else
             raise sprintf( "Error: ApproximateSearch#search unknown type %s ", type )
           end
    prefix   = pair[0]
    _keyword = pair[1]
    trie = DistributedTrie::Trie.new( kvs, prefix )
    trie.fuzzySearch( _keyword, @jarow_shikii )
  end
end