From 9fcb8abd268971f28bcf06dc8193e8a4e2d150e0 Mon Sep 17 00:00:00 2001
From: Dimitris Dafnis <68849116+jim-daf@users.noreply.github.com>
Date: Sat, 25 Apr 2026 21:11:52 +0200
Subject: [PATCH] feat(webview): saveScrollPosition / restoreScrollPosition

Refs #626
---
 .../ferg/awfulapp/webview/AwfulWebView.java   | 32 +++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/Awful.apk/src/main/java/com/ferg/awfulapp/webview/AwfulWebView.java b/Awful.apk/src/main/java/com/ferg/awfulapp/webview/AwfulWebView.java
index eddc3b230..4061e9438 100644
--- a/Awful.apk/src/main/java/com/ferg/awfulapp/webview/AwfulWebView.java
+++ b/Awful.apk/src/main/java/com/ferg/awfulapp/webview/AwfulWebView.java
@@ -172,6 +172,38 @@ public void refreshPageContents() {
     }
 
 
+    /**
+     * Issue #626: capture the current scroll position into a
+     * window-scoped variable so a follow-up content swap can restore it.
+     * Pair with {@link #restoreScrollPosition()} called once the new
+     * body HTML has been rendered.
+     */
+    public void saveScrollPosition() {
+        runJavascript("window.__awfulSavedScroll = window.scrollY;");
+    }
+
+    /**
+     * Restore a previously captured scroll position. Safe to call before
+     * the DOM has finished settling, the JS uses requestAnimationFrame
+     * to retry until the document height covers the saved offset.
+     */
+    public void restoreScrollPosition() {
+        runJavascript(
+                "(function(){" +
+                    "var target = window.__awfulSavedScroll;" +
+                    "if (target == null) { return; }" +
+                    "function tryScroll() {" +
+                        "if (document.documentElement.scrollHeight >= target) {" +
+                            "window.scrollTo({top: target});" +
+                        "} else {" +
+                            "window.requestAnimationFrame(tryScroll);" +
+                        "}" +
+                    "}" +
+                    "tryScroll();" +
+                "})();");
+    }
+
+
     /**
      * Set and display the current HTML for the container body.
      * <p>