module SessionsHelper

 def sign_in(user)
  cookies.permanent.signed[:remember_token] = [user.id, user.salt]
  self.current_user = user
 end

 def current_user=(user)
  @current_user = user
 end

 def current_user
  @current_user || user_from_remember_token
 end

 def signed_in?
  !current_user.nil?
 end

 def sign_out
  cookies.delete(:remember_token)
  @current_user = nil
 end

 private

  def user_from_remember_token
   User.authenticate_with_salt(*remember_token)
  end

  def remember_token
   cookies.signed[:remember_token] || [nil,nil]
  end
end