public function addSocial(AbstractUser $socialUser, $provider)
    {
        $refreshToken = isset($socialUser->refreshToken) && $socialUser->refreshToken
            ? $socialUser->refreshToken
            : null;
        
        $token = is_null($socialUser->token)
            ? $provider
            : $socialUser->token;

        $this->socials()->create([
            'provider'      => $provider,
            'social_id'     => $socialUser->getId(),
            'email'         => $socialUser->getEmail(),
            'avatar'        => $socialUser->getAvatar(),
            'token'         => $token,
            'refresh_token' => $refreshToken,
            'expires_in'    => isset($socialUser->expiresIn) ? $socialUser->expiresIn : null,
        ]);
    }