From 5ae8b1fdd1cf84a564b023314ac7e5b339f5b3b7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=D0=90=D0=BD=D1=82=D0=BE=D0=BD=20=D0=A2=D1=80=D0=BE=D1=88?=
 =?UTF-8?q?=D0=B8=D0=BD?= <i@atroshin.ru>
Date: Wed, 14 Oct 2026 23:32:04 +0300
Subject: [PATCH] v3.28.8: the batch panel's scroll preservation

The attempts box's content is replaced on every render (the batch panel is
static markup; the render fills the dynamic bits) and replacing a
scrollable element's content resets its scroll.  That was harmless while
the render ran once per attempt, but v3.28.7 made it run on every 2 s
poll, so scrolling back through the attempts during a run snapped to the
top each poll.

The render now captures the box's scrollTop before refilling it and
restores it afterwards.

Test: the stub box resets its scroll on an innerHTML write (like a
browser) and the render must keep the reader's position - verified to
fail without the restore.  920 frontend + 928 Python; sw cache
simple-v446.
---
 frontend/index.html              | 10 ++++++++--
 frontend/sw.js                   |  2 +-
 frontend/tests/ram_batch.test.js | 28 ++++++++++++++++++++++++++++
 pyproject.toml                   |  2 +-
 pysim_simple_server/server.py    |  2 +-
 5 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/frontend/index.html b/frontend/index.html
index aadaadc..c7d0055 100644
--- a/frontend/index.html
+++ b/frontend/index.html
@@ -1910,7 +1910,7 @@
 // ===== Version =====
 // Single source of truth for the PWA version: shown in the header and used
 // by the server version check in pysimConnect().
-const SIMPLE_VERSION = '3.28.7';
+const SIMPLE_VERSION = '3.28.8';
 document.getElementById('app-version').textContent = 'v' + SIMPLE_VERSION;
 
 // ===== view history (the browser Back/Forward buttons) =====
@@ -10267,7 +10267,13 @@ function ramBatchRender() {
 		counts.textContent = text;
 	}
 	const box = document.getElementById('ram-batch-attempts');
-	if (box) box.innerHTML = ramBatchAttemptsHtml(st.attempts || []);
+	if (box) {
+		// Replacing the box's content resets its scroll: the render now runs on
+		// every 2 s poll, so keep the reader's position (v3.28.8).
+		const prevScroll = box.scrollTop;
+		box.innerHTML = ramBatchAttemptsHtml(st.attempts || []);
+		if (prevScroll) box.scrollTop = prevScroll;
+	}
 }
 
 function ramBatchAttemptsHtml(attempts) {
diff --git a/frontend/sw.js b/frontend/sw.js
index 7d2b5b6..2c5d0d5 100644
--- a/frontend/sw.js
+++ b/frontend/sw.js
@@ -1,4 +1,4 @@
-const CACHE = 'simple-v445';
+const CACHE = 'simple-v446';
 const URLS = [
   'index.html',
   'help.html',
diff --git a/frontend/tests/ram_batch.test.js b/frontend/tests/ram_batch.test.js
index 8384de8..9532a3d 100644
--- a/frontend/tests/ram_batch.test.js
+++ b/frontend/tests/ram_batch.test.js
@@ -45,6 +45,13 @@ function setEl(id, value) {
 			contains(c) { return !!els[id].classes[c]; },
 		},
 	};
+	if (id === 'ram-batch-attempts') {
+		// like a browser: replacing the content resets the scroll position
+		Object.defineProperty(els[id], 'innerHTML', {
+			get() { return this._html || ''; },
+			set(v) { this._html = v; this.scrollTop = 0; },
+		});
+	}
 	return els[id];
 }
 function clearEls() {
@@ -302,6 +309,27 @@ test('a hung detailed fetch does not freeze the counts (v3.28.7)', async () => {
 	app.hangs = false;
 });
 
+test('the attempts table keeps its scroll position across a poll render (v3.28.8)', () => {
+	clearEls();
+	setEl('ram-op', 'batch');
+	setEl('ram-batch-panel', '');
+	setEl('ram-batch-start', '');
+	setEl('ram-batch-stop', '');
+	setEl('ram-batch-clear', '');
+	setEl('ram-batch-spin', '');
+	setEl('ram-batch-state', '');
+	setEl('ram-batch-notice', '');
+	setEl('ram-batch-counts', '');
+	setEl('ram-batch-attempts', '');
+	app.setLast({ active: true, phase: 'waiting_card', attempts: [
+		{ ts: 1, iccid: '8970119000004600098', preset: 'p', result: 'installed', duration_ms: 1 }],
+		counts: { installed: 1, failed: 0, skipped: 0 }, attempts_total: 1 });
+	app.ramBatchRender();
+	els['ram-batch-attempts'].scrollTop = 120;     // the reader scrolled back
+	app.ramBatchRender();                          // the next 2 s poll render
+	assert.strictEqual(els['ram-batch-attempts'].scrollTop, 120);
+});
+
 test('a stale fetch guard is released so the report recovers (v3.28.7)', async () => {
 	clearEls();
 	setEl('ram-op', 'batch');
diff --git a/pyproject.toml b/pyproject.toml
index a8caa52..4565e59 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "pysim-simple-server"
-version = "3.28.7"
+version = "3.28.8"
 description = "HTTP REST server wrapping pysim for the SIMple PWA"
 requires-python = ">=3.8"
 # pysim is a git-only dependency installed explicitly by setup.bat/setup.sh.
diff --git a/pysim_simple_server/server.py b/pysim_simple_server/server.py
index ee63dd9..12a9dec 100644
--- a/pysim_simple_server/server.py
+++ b/pysim_simple_server/server.py
@@ -37,7 +37,7 @@ from osmocom.tlv import BER_TLV_IE
 from osmocom.utils import rpad
 
 
-VERSION = '3.28.7'
+VERSION = '3.28.8'
 
 MAX_ENVELOPE_SEGMENTS = 5  # max SMS segments for outgoing C-APDU in ENVELOPE