How to manage firebase sign-in in another class

Question

I have 3 different Fragments to sign in. This is one of fragment to sign-in.

@AndroidEntryPoint
class SettingFragment : Fragment(){

lateinit var binding: FragmentSettingBinding
private lateinit var auth: FirebaseAuth
private lateinit var googleSignInClient : GoogleSignInClient

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    auth = Firebase.auth
    configure_google_login()
}

override fun onCreateView(
    inflater: LayoutInflater, container: ViewGroup?,
    savedInstanceState: Bundle?,
): View? {
    binding = FragmentSettingBinding.inflate(inflater,container,false)

    binding.apply {
        btnLogin.setOnClickListener {
            val signInIntent = googleSignInClient.signInIntent
            startActivityForResult(signInIntent, signincode)
        }
    }
    return binding.root
}

override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
    super.onViewCreated(view, savedInstanceState)
}

private fun configure_google_login(){
    val gso = GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
        .requestIdToken(getString(R.string.default_web_client_id))
        .requestEmail()
        .build()
    googleSignInClient = GoogleSignIn.getClient(requireActivity(), gso)
}

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
    super.onActivityResult(requestCode, resultCode, data)
    if (requestCode == signincode) {
        val task = GoogleSignIn.getSignedInAccountFromIntent(data)
        try {
            val account = task.getResult(ApiException::class.java)!!
            firebaseAuthWithGoogle(account.idToken!!) 
        } catch (e: ApiException) {
            Log.i("catch", "$e")
        }
    } else {
        Log.i("else", "onActivityResult else")
    }
}

private fun firebaseAuthWithGoogle(idToken: String) {
    var pd = ProgressDialog(activity)
    pd.setMessage(resources.getString(R.string.loginisprogressing))
    pd.show()

    val credential = GoogleAuthProvider.getCredential(idToken, null)
    auth.signInWithCredential(credential)
        .addOnCompleteListener(requireActivity()) { task ->
            if (task.isSuccessful) {
                pd.dismiss()
            }else{
                Toast.makeText(requireActivity(),"google login failed", Toast.LENGTH_LONG).show()
            }
        }.addOnFailureListener { e ->
            Log.i("google login faile", "$e")
        }
    }
}

I call three method ( 1.configure_google_login() , 2. firebaseAuthWithGoogle() , 3. override onActivityResult() ) , and initialize GoogleSignInClient in this Fragment.

The problem is that I have 3 Fragments to sign-in , and I wrote same code to all of them for sign-in.

I don't think it's desirable and clean design.... I want to manage sign-in in another class so I don't have to write same sign-in code to all 3 Fragments. but I'm having problem to dealt with onActivityResult() in another class.

I searched about it alot to do this, but I couldn't find...

How to manage firebase sign-in in another class??