parsley/app/models/concerns/tokenized_like.rb

module TokenizedLike
  extend ActiveSupport::Concern

  module ClassMethods

    def matches_tokens(attribute, tokens)
      table = self.arel_table
      query = self.all

      tokens.each do |t|
        match1 = "#{t}%"
        match2 = "% #{t}%"
        match3 = "%,#{t}%"

        matcher = ->(m) { table[attribute.to_sym].matches(m) }

        cond = matcher.call(match1).or(matcher.call(match2)).or(matcher.call(match3))

        query = query.where(cond)
      end

      query
    end

    def matches_token(attribute, token)
      table = self.arel_table
      query = self.all
      query.where(table[attribute.to_sym].matches("#{token}%"))
    end

  end
end