func validatePassword(password string) error {
	if len(password) < 6 {
		return datalayer.NewValidationError("Password too short")
	}
	if len(password) > 120 {
		return datalayer.NewValidationError("Password too long")
	}
	return nil
}
func validateUsername(username string) error {
	if username == "leela" {
		return datalayer.NewValidationError("Username reserved")
	}
	if len(username) < 5 {
		return datalayer.NewValidationError("Username too short")
	}
	if len(username) > 24 {
		return datalayer.NewValidationError("Username too long")
	}
	matched, err := regexp.MatchString("^[a-zA-Z][a-zA-Z0-9_]+$", username)
	if !matched || err != nil {
		return datalayer.NewValidationError("Invalid username")
	}

	return nil
}
func validateEmail(email string) error {
	if !emailPattern.MatchString(email) {
		return datalayer.NewValidationError("Invalid email address")
	}
	return nil
}