class User < ApplicationRecord
  attr_accessor :remember_token, :activation_token, :reset_token
  has_many :microposts, dependent: :destroy
  before_save :downcase_email
  before_create :create_activation_digest
  validates :name, presence: true, length: {maximum: 50}
    VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-]+(\.[a-z\d\-]+)*\.[a-z]+\z/i
  validates :email, presence: true, length: {maximum: 255},
                    format: {with: VALID_EMAIL_REGEX},
                    uniqueness: {case_sensitive: false}
  validates :password, presence: true, length: {minimum: 6}, allow_nil: true
  has_secure_password
  
  # Returns the hash digest of the given string
  def User.digest(string)
    cost = ActiveModel::SecurePassword.min_cost ? BCrypt::Engine::MIN_COST :
                                                  BCrypt::Engine.cost
    BCrypt::Password.create(string, cost: cost)
  end
  
  # Returns a random token
  def User.new_token
    SecureRandom.urlsafe_base64
  end
  
   # Remembers a user in the database for use in persistent sessions
  def remember
    self.remember_token = User.new_token
    update_attribute(:remember_digest, User.digest(remember_token))
  end
  
  # Returns true if the given token matches the digest
  def authenticated?(attribute, token)
    digest = send("#{attribute}_digest")
    return false if digest.nil?
    BCrypt::Password.new(digest).is_password?(token)
  end
  
  # Forgets a user
  def forget
    update_attribute(:remember_digest, nil)
  end
  
  # Activates an account
  def activate
    update_columns(activated: true, activated_at: Time.zone.now)
  end
  
  def send_activation_email
    UserMailer.account_activation(self).deliver_now
  end
  
  def create_reset_digest
    self.reset_token = User.new_token
    update_columns(reset_digest: User.digest(reset_token), 
                   reset_sent_at: Time.zone.now)
  end
  
  def send_password_reset_email
    UserMailer.password_reset(self).deliver_now
  end
  
  def password_reset_expired?
    reset_sent_at < 2.hours.ago
  end
  
  def feed
    Micropost.where("user_id = ?", id)
  end
  
  private
  
    # Converts email to all lowercase
    def downcase_email
      email.downcase!
    end
    
    # Creates and assigns the activation token and digest
    def create_activation_digest
      self.activation_token = User.new_token
      self.activation_digest = User.digest(activation_token)
    end
    
end
