public Task silentSignIn()

in auth/src/main/java/com/firebase/ui/auth/AuthUI.java [310:379]
58 lines of code
10 McCabe index (conditional complexity)

    public Task<AuthResult> silentSignIn(@NonNull Context context,
                                         @NonNull List<IdpConfig> configs) {
        if (mAuth.getCurrentUser() != null) {
            throw new IllegalArgumentException("User already signed in!");
        }

        final Context appContext = context.getApplicationContext();
        final IdpConfig google =
                ProviderUtils.getConfigFromIdps(configs, GoogleAuthProvider.PROVIDER_ID);
        final IdpConfig email =
                ProviderUtils.getConfigFromIdps(configs, EmailAuthProvider.PROVIDER_ID);

        if (google == null && email == null) {
            throw new IllegalArgumentException("No supported providers were supplied. " +
                    "Add either Google or email support.");
        }

        final GoogleSignInOptions googleOptions;
        if (google == null) {
            googleOptions = null;
        } else {
            GoogleSignInAccount last = GoogleSignIn.getLastSignedInAccount(appContext);
            if (last != null && last.getIdToken() != null) {
                return mAuth.signInWithCredential(GoogleAuthProvider.getCredential(
                        last.getIdToken(), null));
            }

            googleOptions = google.getParams()
                    .getParcelable(ExtraConstants.GOOGLE_SIGN_IN_OPTIONS);
        }

        // If Play services are not available we can't attempt to use the credentials client.
        if (!GoogleApiUtils.isPlayServicesAvailable(context)) {
            return Tasks.forException(
                    new FirebaseUiException(ErrorCodes.PLAY_SERVICES_UPDATE_CANCELLED));
        }

        return GoogleApiUtils.getCredentialsClient(context)
                .request(new CredentialRequest.Builder()
                        // We can support both email and Google at the same time here because they
                        // are mutually exclusive. If a user signs in with Google, their email
                        // account will automatically be upgraded (a.k.a. replaced) with the Google
                        // one, meaning Smart Lock won't have to show the picker UI.
                        .setPasswordLoginSupported(email != null)
                        .setAccountTypes(google == null ? null :
                                ProviderUtils.providerIdToAccountType(GoogleAuthProvider
                                        .PROVIDER_ID))
                        .build())
                .continueWithTask(task -> {
                    Credential credential = task.getResult().getCredential();
                    String email1 = credential.getId();
                    String password = credential.getPassword();

                    if (TextUtils.isEmpty(password)) {
                        return GoogleSignIn.getClient(appContext,
                                new GoogleSignInOptions.Builder(googleOptions)
                                        .setAccountName(email1)
                                        .build())
                                .silentSignIn()
                                .continueWithTask(task1 -> {
                                    AuthCredential authCredential = GoogleAuthProvider
                                            .getCredential(
                                                    task1.getResult().getIdToken(), null);
                                    return mAuth.signInWithCredential(authCredential);
                                });
                    } else {
                        return mAuth.signInWithEmailAndPassword(email1, password);
                    }
                });
    }