require 'digest/sha2'
class User < ActiveRecord::Base
  validates_presence_of   :username, :first_name, :last_name, :email
  validates_length_of       :username, :within => 6..20, :too_long => "pick a shorter username", :too_short => "pick a longer username"
  validates_uniqueness_of :username, :message => "Another user by the same username exists please try another username"

  validates_format_of :email, :with => /^([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})$/i, :on => :create

  has_many      :tasks

  def self.authenticate(username, password)
    find(:first, :conditions => ["username = ? and password_hash = ?", username, Digest::SHA2.hexdigest(password + self.password_salt)])
  end

  def password=(pass)
    salt = [Array.new(6){rand(256).chr}.join].pack("m").chomp
    write_attribute("password_hash", Digest::SHA256.hexdigest(pass + salt))
    write_attribute("password_salt", salt)
    #self.password_salt, self.password_hash = salt, Digest::SHA256.hexdigest(pass + salt)
  end

  def password_is?(pass)
    Digest::SHA2.hexdigest(pass + self.password_salt) == self.password_hash
  end
end