user.rb

def self.authenticate(username_or_email="", login_password="")
  if  EMAIL_REGEX.match(username_or_email)    
    user = User.find_by_email(username_or_email)
  else
    user = User.find_by_username(username_or_email)
  end
  if user && user.match_password(login_password)
    return user
  else
    return false
  end
end   
def match_password(login_password="")
  encrypted_password == BCrypt::Engine.hash_secret(login_password, salt)
end