class User < ActiveRecord::Base
  attr_accessor   :password
  attr_accessible :name, :email, :password, :password_confirmation

  has_one  :nutrition_profile

  has_many :microposts,    :dependent => :destroy
  has_many :relationships, :dependent => :destroy,
                           :foreign_key => "follower_id"
  has_many :reverse_relationships, :dependent => :destroy,
                                   :foreign_key => "followed_id",
                                   :class_name => "Relationship"
  has_many :following, :through => :relationships, :source => :followed
  has_many :followers, :through => :reverse_relationships,
                       :source  => :follower

  email_regex = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i

  validates :name,  :presence => true,
                    :length   => { :maximum => 50 }
  validates :email, :presence   => true,
                    :format     => { :with => email_regex },
                    :uniqueness => { :case_sensitive => false }
  validates :password, :presence => true,
                       :confirmation => true,
                       :length => { :within => 6..40 }

  before_save :encrypt_password

  def has_password?(submitted_password)
    encrypted_password == encrypt(submitted_password)
  end

  def has_nutrition_profile?
    if (NutritionProfile.where(:user_id => :id).count < 1)
      false
    else
      true
    end
  end

  def feed
    Micropost.from_users_followed_by(self)
  end

  def following?(followed)
    relationships.find_by_followed_id(followed)
  end

  def follow!(followed)
    relationships.create!(:followed_id => followed.id)
  end

  def unfollow!(followed)
    relationships.find_by_followed_id(followed).destroy
  end

  class << self
    def authenticate(email, submitted_password)
      user = find_by_email(email)
      (user && user.has_password?(submitted_password)) ? user : nil
    end

    def authenticate_with_salt(id, cookie_salt)
      user = find_by_id(id)
      (user && user.salt == cookie_salt) ? user : nil
    end
  end

  private

    def encrypt_password
      self.salt = make_salt if new_record?
      self.encrypted_password = encrypt(password)
    end

    def encrypt(string)
      secure_hash("#{salt}--#{string}")
    end

    def make_salt
      secure_hash("#{Time.now.utc}--#{password}")
    end

    def secure_hash(string)
      Digest::SHA2.hexdigest(string)
    end
end