account.rb

require 'digest/sha1'
class Account < ActiveRecord::Base
  # Virtual attribute for the unencrypted password
  attr_accessor :password

  validates_presence_of     :first_name, :last_name, :login, :email_address, :phone_number
  validates_presence_of     :password,                   :if => :password_required?
  validates_presence_of     :password_confirmation,      :if => :password_required?
  validates_length_of       :password, :within => 4..40, :if => :password_required?
  validates_confirmation_of :password,                   :if => :password_required?
  validates_length_of       :login,    :within => 3..40
  validates_length_of       :email_address,    :within => 3..100
  validates_uniqueness_of   :login, :email_address, :case_sensitive => false
  before_save :encrypt_password
  
  attr_accessible :first_name, :last_name, :phone_number, :login, :email_address, :password, :password_confirmation

  acts_as_state_machine :initial => :pending
  state :passive
  state :pending, :enter => :make_activation_code
  state :active,  :enter => :do_activate
  state :suspended
  state :deleted, :enter => :do_delete

  event :register do
    transitions :from => :passive, :to => :pending, :guard => Proc.new {|u| !(u.crypted_password.blank? && u.password.blank?) }
  end
  
  event :activate do
    transitions :from => :pending, :to => :active 
  end
  
  event :suspend do
    transitions :from => [:passive, :pending, :active], :to => :suspended
  end
  
  event :delete do
    transitions :from => [:passive, :pending, :active, :suspended], :to => :deleted
  end

  event :unsuspend do
    transitions :from => :suspended, :to => :active,  :guard => Proc.new {|u| !u.activated_at.blank? }
    transitions :from => :suspended, :to => :pending, :guard => Proc.new {|u| !u.activation_code.blank? }
    transitions :from => :suspended, :to => :passive
  end

  # Authenticates a user by their login name and unencrypted password.  Returns the user or nil.
  def self.authenticate(login, password)
    u = find_in_state :first, :active, :conditions => {:login => login} # need to get the salt
    u && u.authenticated?(password) ? u : nil
  end

  # Encrypts some data with the salt.
  def self.encrypt(password, salt)
    Digest::SHA1.hexdigest("--#{salt}--#{password}--")
  end

  # Encrypts the password with the user salt
  def encrypt(password)
    self.class.encrypt(password, salt)
  end

  def authenticated?(password)
    crypted_password == encrypt(password)
  end

  def remember_token?
    remember_token_expires_at && Time.now.utc < remember_token_expires_at 
  end

  # These create and unset the fields required for remembering users between browser closes
  def remember_me
    remember_me_for 2.weeks
  end

  def remember_me_for(time)
    remember_me_until time.from_now.utc
  end

  def remember_me_until(time)
    self.remember_token_expires_at = time
    self.remember_token            = encrypt("#{email_address}--#{remember_token_expires_at}")
    save(false)
  end

  def forget_me
    self.remember_token_expires_at = nil
    self.remember_token            = nil
    save(false)
  end

  protected
    # before filter 
    def encrypt_password
      return if password.blank?
      self.salt = Digest::SHA1.hexdigest("--#{Time.now.to_s}--#{login}--") if new_record?
      self.crypted_password = encrypt(password)
    end
      
    def password_required?
      crypted_password.blank? || !password.blank?
    end
    
    def make_activation_code
      self.deleted_at = nil
      self.activation_code = Digest::SHA1.hexdigest( Time.now.to_s.split(//).sort_by {rand}.join )
    end
    
    def do_delete
      self.deleted_at = Time.now.utc
    end

    def do_activate
      self.activated_at = Time.now.utc
      self.deleted_at = self.activation_code = nil
    end
end