require 'digest/sha1'

class User < ActiveRecord::Base

  validates_presence_of   :name,
                          :password,
                          :password_confirmation

  validates_uniqueness_of :name

  validates_length_of     :password,
                          :minimum => 5,
                          :message => "should be at least 5 characters long"

  attr_accessor :password_confirmation
  validates_confirmation_of :password



  def password
    @password
  end

  def password=(pwd)
    @password = pwd
    create_new_salt
    self.hashed_password = User.encrypted_password(self.password, self.salt)
  end

  def self.authenticate(name, password)
    user = self.find_by_name(name)
    if user
      expected_password = encrypted_password(password, user.salt)
      if user.hashed_password != expected_password
        user = nil
      end
    end
    user
  end


  private

  def self.encrypted_password(password, salt)
    string_to_hash = password + "w5i4b7b1l" + salt
    Digest::SHA1.hexdigest(string_to_hash)
  end

  def create_new_salt
    self.salt = self.object_id.to_s + rand.to_s
  end

end