password.rb

class Password < String

  POSSIBLE_STRENGTHS = { 1 => "senha fraca", 2 => "senha média", 3 => "senha forte" }

  def self.check_strength(password)
    strength = 1
    if password.length >= 8 || (password.length > 6 && password =~ /[a-z]/ && password =~ /[0-9]/)
      strength+=1
    end
    if password.length > 12 && password =~ /[a-z]/ && password =~ /[A-Z]/ && password =~ /[0-9]/ && password =~ /[^a-zA-Z0-9_\s]/
      strength+=1
    end
    POSSIBLE_STRENGTHS[strength]
  end

  def strength
    Password.check_strength(self)
  end

end