search_suggest.rb

module LCBO
  class SearchSuggest

    STOP_WORDS = %w[ woods ]

    require 'amatch'
    require 'stringex'

    def initialize(db)
      @db = db
      populate_dictionary!
    end

    def query(term)
      dterm = term.downcase
      @dictionary.inject({}) do |hsh, word|
        hsh.merge(Amatch::Levenshtein.new(word).match(dterm) => word)
      end.min[1]
    end

    private

    def populate_dictionary!
      @dictionary = @db.connection[:products].
        select(:name).
        all.
        map do |row|
          row[:name].
            to_ascii.
            downcase.
            gsub(/[0-9]+|[\*\'\.]/, '').
            gsub('-', ' ').
            strip.
            split
        end.
        flatten.
        reject! do |word|
          word.length < 5 ||
          STOP_WORDS.include?(word)
        end.
        uniq.
        sort
    end

  end
end