From 16c7c4431344a0cc11ce08e885e62eeae0e791ee Mon Sep 17 00:00:00 2001
From: artdeell <ultramaksim@gmail.com>
Date: Fri, 3 Nov 2023 17:08:56 +0300
Subject: [PATCH] Feat[mslogin]: handle WebView state saving

---
 .../fragments/MicrosoftLoginFragment.java     | 57 ++++++++++++++-----
 1 file changed, 43 insertions(+), 14 deletions(-)

diff --git a/app_pojavlauncher/src/main/java/net/kdt/pojavlaunch/fragments/MicrosoftLoginFragment.java b/app_pojavlauncher/src/main/java/net/kdt/pojavlaunch/fragments/MicrosoftLoginFragment.java
index 5c41d0f8b..316de8424 100644
--- a/app_pojavlauncher/src/main/java/net/kdt/pojavlaunch/fragments/MicrosoftLoginFragment.java
+++ b/app_pojavlauncher/src/main/java/net/kdt/pojavlaunch/fragments/MicrosoftLoginFragment.java
@@ -4,6 +4,7 @@ import android.annotation.SuppressLint;
 import android.graphics.Bitmap;
 import android.net.Uri;
 import android.os.Bundle;
+import android.util.Log;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
@@ -13,6 +14,7 @@ import android.webkit.WebView;
 import android.webkit.WebViewClient;
 import android.widget.Toast;
 
+import androidx.annotation.NonNull;
 import androidx.fragment.app.Fragment;
 
 import net.kdt.pojavlaunch.R;
@@ -24,30 +26,57 @@ public class MicrosoftLoginFragment extends Fragment {
     public static final String TAG = "MICROSOFT_LOGIN_FRAGMENT";
     private WebView mWebview;
 
-
     @Override
     public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
         mWebview = (WebView) inflater.inflate(R.layout.fragment_microsoft_login, container, false);
-        CookieManager.getInstance().removeAllCookies(this::onCookiesRemoved);
+        setWebViewSettings();
+        if(savedInstanceState == null) startNewSession();
+        else restoreWebViewState(savedInstanceState);
         return mWebview;
     }
 
-    @SuppressLint("SetJavaScriptEnabled") // required for Microsoft log-in
-    public void onCookiesRemoved(Boolean b) {
+    // WebView.restoreState() does not restore the WebSettings or the client, so set them there
+    // separately. Note that general state should not be altered here (aka no loading pages, no manipulating back/front lists),
+    // to avoid "undesirable side-effects"
+    @SuppressLint("SetJavaScriptEnabled")
+    private void setWebViewSettings() {
         WebSettings settings = mWebview.getSettings();
-
         settings.setJavaScriptEnabled(true);
-        mWebview.clearHistory();
-        mWebview.clearCache(true);
-        mWebview.clearFormData();
-        mWebview.clearHistory();
         mWebview.setWebViewClient(new WebViewTrackClient());
+    }
 
-        mWebview.loadUrl("https://login.live.com/oauth20_authorize.srf" +
-                "?client_id=00000000402b5328" +
-                "&response_type=code" +
-                "&scope=service%3A%3Auser.auth.xboxlive.com%3A%3AMBI_SSL" +
-                "&redirect_url=https%3A%2F%2Flogin.live.com%2Foauth20_desktop.srf");
+    private void startNewSession() {
+        CookieManager.getInstance().removeAllCookies((b)->{
+            mWebview.clearHistory();
+            mWebview.clearCache(true);
+            mWebview.clearFormData();
+            mWebview.clearHistory();
+            mWebview.loadUrl("https://login.live.com/oauth20_authorize.srf" +
+                    "?client_id=00000000402b5328" +
+                    "&response_type=code" +
+                    "&scope=service%3A%3Auser.auth.xboxlive.com%3A%3AMBI_SSL" +
+                    "&redirect_url=https%3A%2F%2Flogin.live.com%2Foauth20_desktop.srf");
+        });
+    }
+
+    private void restoreWebViewState(Bundle savedInstanceState) {
+        Log.i("MSAuthFragment","Restoring state...");
+        if(mWebview.restoreState(savedInstanceState) == null) {
+            Log.w("MSAuthFragment", "Failed to restore state, starting afresh");
+            // if, for some reason, we failed to restore our session,
+            // just start afresh
+            startNewSession();
+        }
+    }
+
+    @Override
+    public void onSaveInstanceState(@NonNull Bundle outState) {
+        // Since the value cannot be null, just creaqte a "blank" client. This is done to not let Android
+        // kill us if something happens after onSaveInstanceState
+        mWebview.setWebViewClient(new WebViewClient());
+        mWebview.saveState(outState);
+        super.onSaveInstanceState(outState);
+        // if something happens after this, well, too bad
     }
 
     /* Expose webview actions to others */