# approximatesearch.rb  -  "approximate search library"
#  
#   Copyright (c) 2010  Kiyoka Nishiyama  <kiyoka@sumibi.org>
#   
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#   modification, are permitted provided that the following conditions
#   are met:
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#      notice, this list of conditions and the following disclaimer.
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#      software without specific prior written permission.
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#  
#  $Id: 
#
require 'fuzzystringmatch'
require 'sekka/kvs'

class ApproximateSearch
  def initialize( jarow_shikii )
    @jarow_shikii = jarow_shikii
    @jarow        = FuzzyStringMatch::JaroWinkler.new.create( :native )
  end

  def filtering( keyword, arr )
    keyword = keyword.downcase
    arr.map { |str|
      val = @jarow.getDistance( keyword, str.downcase )
      #printf( "   [%s] vs [%s] => %f\n", keyword, str.downcase, val )
      (val > @jarow_shikii) ? [ val, str ] : false
    }.select { |v| v }.sort_by {|item| 1.0 - item[0]}
  end

  def search( userid, kvs, keyword, type )
    readymade_key = case type
                    when 'k' # okuri nashi kanji entry
                      "(" + keyword.slice( 0, 2 ).downcase + ")"
                    when 'K' # okuri ari   kanji entry
                      "(" + keyword.slice( 0, 2 ).upcase   + ")"
                    when 'h' # hiragana phrase entry
                      "{" + keyword.slice( 1, 2 ).downcase + "}"
                    else
                      raise sprintf( "Error: ApproximateSearch#search unknown type %s ", type )
                    end

    str = kvs.get( userid + "::" + readymade_key, false )
    if not str
      str = kvs.get( "MASTER::" + readymade_key )
    end

    #printf( "#readymade_key %s : %s\n", readymade_key, str )
    if str
      filtering( keyword, str.split( /[ ]+/ ))
    else
      [ ]
    end
  end
end