Pagekit\User\Model\User::validate PHP Method

    public function validate()
    {
        if (empty($this->name)) {
            throw new Exception(__('Name required.'));
        }
        if (empty($this->password)) {
            throw new Exception(__('Password required.'));
        }
        if (!preg_match('/^[a-zA-Z0-9._\\-]{3,}$/', $this->username)) {
            throw new Exception(__('Username is invalid.'));
        }
        // TODO: email validation differs from email validation in vuejs
        if (!filter_var($this->email, FILTER_VALIDATE_EMAIL)) {
            throw new Exception(__('Email is invalid.'));
        }
        if (self::where(['id <> :id'], ['id' => $this->id ?: 0])->where(function ($query) {
            $query->orWhere(['LOWER(username) = :username', 'LOWER(email) = :username'], ['username' => strtolower($this->username)]);
        })->first()) {
            throw new Exception(__('Username not available.'));
        }
        if (self::where(['id <> :id'], ['id' => $this->id ?: 0])->where(function ($query) {
            $query->orWhere(['LOWER(username) = :email', 'LOWER(email) = :email'], ['email' => strtolower($this->email)]);
        })->first()) {
            throw new Exception(__('Email not available.'));
        }
        return true;
    }