fix: [IOCOM-1994,IOCOM-1995] Fix for back behaviours on FIMS Auth (#6481

)

## Short description
This PR fixes some anomalies on the back behaviour for the FIMS' Auth
flow

## List of changes proposed in this pull request
- When going back from an error screen, proper deallocation of FIMS
resources was not triggered (using navigation.back instead of back saga)
- On Android, physical back button event is not handled by the
assistance modal and is propagated to the underlying screen. If this
happens on the FIMS' consents screen, the flow is interrupted. Since
this anomaly affects the entire app, the back capturing has been
disabled and the user has to rely on the UI back buttons

## How to test
Using the io-dev-api-server, check that:
- the FIMS flow can be successfully retried after an error
- the Android back button does nothing on the FIMS' Auth flow

Co-authored-by: Martino Cesari Tomba <[email protected]>

ts/features/fims/singleSignOn/components/FimsFullScreenErrors.tsx

@@ -1,28 +1,35 @@
-import { useNavigation } from "@react-navigation/native";
 import * as React from "react";
 import {
   OperationResultScreenContent,
   OperationResultScreenContentProps
 } from "../../../../components/screens/OperationResultScreenContent";
 import I18n from "../../../../i18n";
-import { useIOSelector } from "../../../../store/hooks";
+import { useIODispatch, useIOSelector } from "../../../../store/hooks";
 import {
   fimsAuthenticationErrorTagSelector,
   fimsDebugDataSelector
 } from "../store/selectors";
 import { useDebugInfo } from "../../../../hooks/useDebugInfo";
+import { fimsCancelOrAbortAction } from "../store/actions";
 
 export const FimsSSOFullScreenError = () => {
-  const navigation = useNavigation();
+  const dispatch = useIODispatch();
   const errorTag = useIOSelector(fimsAuthenticationErrorTagSelector);
   const debugData = useIOSelector(fimsDebugDataSelector);
+
   const debugInfo = React.useMemo(
     () => ({
       fimsFailure: `${errorTag}: ${debugData}`
     }),
     [debugData, errorTag]
   );
   useDebugInfo(debugInfo);
+
+  const handleClose = React.useCallback(
+    () => dispatch(fimsCancelOrAbortAction()),
+    [dispatch]
+  );
+
   const getErrorComponentProps = (): OperationResultScreenContentProps => {
     switch (errorTag) {
       case "AUTHENTICATION":
@@ -35,7 +42,7 @@ export const FimsSSOFullScreenError = () => {
           pictogram: "umbrellaNew",
           action: {
             label: I18n.t("global.buttons.close"),
-            onPress: navigation.goBack
+            onPress: handleClose
           }
         };
       case "MISSING_INAPP_BROWSER":
@@ -50,7 +57,7 @@ export const FimsSSOFullScreenError = () => {
           pictogram: "updateOS",
           action: {
             label: I18n.t("global.buttons.close"),
-            onPress: navigation.goBack
+            onPress: handleClose
           }
         };
       default:
@@ -61,7 +68,7 @@ export const FimsSSOFullScreenError = () => {
           pictogram: "umbrellaNew",
           action: {
             label: I18n.t("global.buttons.close"),
-            onPress: navigation.goBack
+            onPress: handleClose
           }
         };
     }

ts/features/fims/singleSignOn/screens/FimsFlowHandlerScreen.tsx

@@ -1,6 +1,6 @@
 import { Body, IOStyles } from "@pagopa/io-app-design-system";
 import * as pot from "@pagopa/ts-commons/lib/pot";
-import { pipe } from "fp-ts/lib/function";
+import { constTrue, pipe } from "fp-ts/lib/function";
 import * as O from "fp-ts/Option";
 import * as React from "react";
 import { View } from "react-native";
@@ -64,10 +64,12 @@ export const FimsFlowHandlerScreen = (
     goBack: handleCancelOrAbort
   });
 
-  useHardwareBackButton(() => {
-    handleCancelOrAbort();
-    return true;
-  });
+  // Force users on Android to use UI buttons to go back, since
+  // there are cases where a modal may be displayed on top of
+  // the screen (like the assistance one) and the hardware back
+  // button event is not stopped by such screen but is instead
+  // propagated to this UI, causing a back loop
+  useHardwareBackButton(constTrue);
 
   React.useEffect(() => {
     if (ctaUrl && !requiresAppUpdate) {