class User < ApplicationRecord
    attr_accessor :remember_token
    before_save { email.downcase! }
    validates :name, presence: true, length: { maximum: 50 }
    VALID_EMAIL_REGEX = /\A[\w+\-.]+@[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 }

    has_secure_password

    # 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

    # Forgets a user
    def forget
      update_attribute(:remember_digest, nil)
    end

    # Returns true if the given token matches the digest
    def authenticated?(remember_token)
      return false if remember_digest.nil?
      BCrypt::Password.new(remember_digest).is_password?(remember_token)
    end

    # 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
end