From 7cc8fa0b9eb160dd8a416108216c0441c6c480e2 Mon Sep 17 00:00:00 2001
From: Dani Palou <dani@moodle.com>
Date: Fri, 4 Jun 2021 12:56:13 +0200
Subject: [PATCH] MOBILE-3320 android: Fix back button with leave guards

---
 src/app/app.component.ts                           | 13 +++++++++----
 src/core/features/login/services/login-helper.ts   |  8 ++------
 src/core/features/mainmenu/pages/menu/menu.ts      | 14 ++++----------
 .../features/mainmenu/pages/more/more.module.ts    |  3 +++
 src/core/services/app.ts                           |  8 ++++++++
 5 files changed, 26 insertions(+), 20 deletions(-)

diff --git a/src/app/app.component.ts b/src/app/app.component.ts
index 7457bda23..713c57567 100644
--- a/src/app/app.component.ts
+++ b/src/app/app.component.ts
@@ -224,11 +224,17 @@ export class AppComponent implements OnInit, AfterViewInit {
         document.addEventListener('ionBackButton', (event: BackButtonEvent) => {
             // This callback should have the lowest priority in the app.
             event.detail.register(-100, async () => {
+                const initialPath = CoreNavigator.getCurrentPath();
+                if (initialPath.startsWith('/main/')) {
+                    // Main menu has its own callback to handle back. If this callback is called it means we should exit app.
+                    CoreApp.closeApp();
+
+                    return;
+                }
+
                 // This callback can be called at the same time as Ionic's back navigation callback.
                 // Check if the path changes due to the back navigation handler, to know if we're at root level.
                 // Ionic doc recommends IonRouterOutlet.canGoBack, but there's no easy way to get the current outlet from here.
-                const initialPath = CoreNavigator.getCurrentPath();
-
                 // The path seems to change immediately (0 ms timeout), but use 50ms just in case.
                 await CoreUtils.wait(50);
 
@@ -238,8 +244,7 @@ export class AppComponent implements OnInit, AfterViewInit {
                 }
 
                 // Quit the app.
-                const nav = <any> window.navigator; // eslint-disable-line @typescript-eslint/no-explicit-any
-                nav.app?.exitApp();
+                CoreApp.closeApp();
             });
         });
     }
diff --git a/src/core/features/login/services/login-helper.ts b/src/core/features/login/services/login-helper.ts
index 5ebfdfe8e..955ac5457 100644
--- a/src/core/features/login/services/login-helper.ts
+++ b/src/core/features/login/services/login-helper.ts
@@ -661,9 +661,7 @@ export class CoreLoginHelperProvider {
 
         // Always open it in browser because the user might have the session stored in there.
         CoreUtils.openInBrowser(loginUrl);
-
-        const nav = <any> window.navigator; // eslint-disable-line @typescript-eslint/no-explicit-any
-        nav.app?.exitApp();
+        CoreApp.closeApp();
 
         return true;
     }
@@ -695,9 +693,7 @@ export class CoreLoginHelperProvider {
             });
         } else {
             CoreUtils.openInBrowser(loginUrl);
-
-            const nav = <any> window.navigator; // eslint-disable-line @typescript-eslint/no-explicit-any
-            nav.app?.exitApp();
+            CoreApp.closeApp();
         }
     }
 
diff --git a/src/core/features/mainmenu/pages/menu/menu.ts b/src/core/features/mainmenu/pages/menu/menu.ts
index 0bba478b1..b2c968bbd 100644
--- a/src/core/features/mainmenu/pages/menu/menu.ts
+++ b/src/core/features/mainmenu/pages/menu/menu.ts
@@ -226,16 +226,10 @@ export class CoreMainMenuPage implements OnInit, OnDestroy {
         // Use a priority lower than 0 (navigation).
         event.detail.register(-10, async (processNextHandler: () => void) => {
             // This callback can be called at the same time as Ionic's back navigation callback.
-            // Check if the path changes due to the back navigation handler, to know if we're at root level of the tab.
-            // Ionic doc recommends IonRouterOutlet.canGoBack, but there's no easy way to get the current outlet from here.
-            const initialPath = CoreNavigator.getCurrentPath();
-
-            // The path seems to change immediately (0 ms timeout), but use 50ms just in case.
-            await CoreUtils.wait(50);
-
-            if (CoreNavigator.getCurrentPath() != initialPath) {
-                // Ionic has navigated back, nothing else to do.
-                return;
+            // Check if user is already at the root of a tab.
+            const mainMenuRootRoute = CoreNavigator.getCurrentRoute({ routeData: { isMainMenuRoot: true } });
+            if (!mainMenuRootRoute) {
+                return; // Not at root level, let Ionic handle the navigation.
             }
 
             // No back navigation, already at root level. Check if we should change tab.
diff --git a/src/core/features/mainmenu/pages/more/more.module.ts b/src/core/features/mainmenu/pages/more/more.module.ts
index 48cd31b3b..e1a10ac61 100644
--- a/src/core/features/mainmenu/pages/more/more.module.ts
+++ b/src/core/features/mainmenu/pages/more/more.module.ts
@@ -30,6 +30,9 @@ import { buildTabMainRoutes } from '@features/mainmenu/mainmenu-tab-routing.modu
             deps: [Injector],
             useFactory: (injector: Injector) => buildTabMainRoutes(injector, {
                 component: CoreMainMenuMorePage,
+                data: {
+                    isMainMenuRoot: true,
+                },
             }),
         },
     ],
diff --git a/src/core/services/app.ts b/src/core/services/app.ts
index 8430448e2..27dc93587 100644
--- a/src/core/services/app.ts
+++ b/src/core/services/app.ts
@@ -562,6 +562,14 @@ export class CoreAppProvider {
         return redirect;
     }
 
+    /**
+     * Close the app.
+     */
+    closeApp(): void {
+        const nav = <any> window.navigator; // eslint-disable-line @typescript-eslint/no-explicit-any
+        nav.app?.exitApp();
+    }
+
     /**
      * Forget redirect data.
      */