Regalia v1.0.1

[YDW99]

What's Changed

• 2026.6.17 by @YDW99 in 2026.6.17 #3

New Contributors

• @YDW99 made their first contribution in 2026.6.17 #3

Full Changelog: v1.0.0...v1.0.1

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Regalia v1.0.1 — Release Notes

A pocket-sized international chess companion powered by Stockfish 18.
Built for Android, refined for Xiaomi HyperOS 3.

Version	1.0.1
Version Code	101
Target SDK	35 (Android 15)
Min SDK	21 (Android 5.0 Lollipop)
ABI	arm64-v8a (with .dotprod flag)
Engine	Stockfish 18 (single, hardcoded)
APK Size	~74 MB
Signatures	v1 ✅ · v2 ✅ · v3 ✅
Release Date	2026-06-17

The notification retains its other v1.0.1 properties:

• 📌 Non-removable — setOngoing(true) + FLAG_NO_CLEAR.
• 👆 Click-to-open — PendingIntent launches MainActivity.
• 🔕 Silent — setOnlyAlertOnce(true) + setShowWhen(false).
• 🏠 Local-only — setLocalOnly(true), no remote mirroring.

// EngineService.java — buildNotification()
Notification n = new NotificationCompat.Builder(this, CHANNEL_ID)
    .setContentTitle(getString(R.string.app_name))
    .setContentText(getString(R.string.notif_ready))      // ← was depth/nps
    .setSmallIcon(R.drawable.ic_stat_chess)
    .setOngoing(true)
    .setOnlyAlertOnce(true)
    .setShowWhen(false)
    .setLocalOnly(true)
    .setCategory(NotificationCompat.CATEGORY_SERVICE)
    .setContentIntent(openAppIntent)
    .build();

Note

On Android 14+, the user can still dismiss the notification via the
notification shade long-press menu — the OS overrides setOngoing at that
level. The foreground service itself continues running. There is no API
to prevent this short of becoming the device's lock-screen app.

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# Regalia v1.0.1 — Release Notes

A pocket-sized international chess companion powered by Stockfish 18.
Built for Android, refined for Xiaomi HyperOS 3.

Version	1.0.1
Version Code	101
Target SDK	35 (Android 15)
Min SDK	21 (Android 5.0 Lollipop)
ABI	arm64-v8a (with .dotprod flag)
Engine	Stockfish 18 (single, hardcoded)
APK Size	~74 MB
Signatures	v1 ✅ · v2 ✅ · v3 ✅
Release Date	2026-06-17

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Table of Contents

1. [Overview]
2. [What's New in v1.0.1]
3. [Deep-Dive: Each Change]
4. [Technical Specifications]
5. [Security Posture]
6. [Build & Signing Pipeline]
7. [Deliverable Manifest]
8. [Compatibility Matrix]
9. [Known Behavior & Notes]
10. [Acknowledgments]
11. [License]

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Overview

Regalia is a single-player-first chess application for Android that bundles the
Stockfish 18 engine as its sole analysis backend. The app is intentionally
minimalist: no telemetry, no cloud accounts, no analytics SDKs — every gram of
binary weight goes toward the engine and the on-device review experience.

The v1.0.1 release is a refinement patch over v1.0.0. It does not introduce
new major features; instead, it polishes six rough edges reported through
real-world use: a notification bar that was too chatty, an undo button that
silently failed to re-select the moved piece, PGN imports that lost variation
branches under non-standard SAN, and a screenshot policy that was too strict
for casual sharing.

Note

The version number stays at 1.0.1. This file documents the final state
of the v1.0.1 release after both rounds of fixes (initial bundle + follow-up
refinement round).

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What's New in v1.0.1

A bird's-eye view of every change shipped in this version, relative to v1.0.0.

Summary Table

#	Area	Change	Severity
1	UX	Screenshots are now allowed (FLAG_SECURE removed)	Minor
2	UX	Notification bar simplified to three states: ready / analyzing / error	Minor
3	Bug	Undo auto-select now reliably highlights the un-done piece	High
4	Bug	PGN variation parsing hardened against non-standard SAN	High
5	Bug	PGN import undo can now rewind to white's first move	High
6	Maint	Code cleanup — docstrings, redundant fallback removed	Trivial
7	Perf	GPU compositing hints on board & piece layers	Minor
8	UX	Haptic feedback on language toggle	Trivial
9	Sec	Defense-in-depth TLS pinning, CT, SafetyNet shims	Minor

Tip

Items 1–6 were the user's explicit requests for this round. Items 7–9
were carried over from the initial v1.0.1 bundle and remain in this release.

At a Glance

• ✅ Screenshots work everywhere — board, review screen, recent tasks thumbnail.
• 🔔 Notification bar shows one word: Ready, Analyzing, or Engine error: …
• ↩️ Undo re-selects the piece that just moved back; tap empty square to deselect.
• 🌳 PGN variations survive non-standard SAN (missing disambiguation, +/# suffixes).
• ⏮️ PGN import no longer traps white's first move in an "undo-resistant" state.
• 🧹 Dead fallback path removed from undoMove; docstrings refreshed.

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Deep-Dive: Each Change

1. Code Fixes & Improvements

• Move evaluation labels: In English mode, the label "Book" has been replaced with "Mediocre" (Chinese label "标准" remains unchanged).

• Opening selection crash fix – Root cause: Opening names containing apostrophes (e.g., Queen's Pawn, Anderssen's, From's Gambit) were only HTML-escaped (_esc) in the onclick handler, not JavaScript string-escaped. The HTML parser restored ' to ', which truncated the JavaScript string and triggered "Unexpected identifier 's'". Fixed by replacing _esc with _escJs() in both ui.js and game-logic.js.

• MobSF security hardening (each researched, evaluated for trade-offs, and implemented accordingly):

  • Disabled all three WebView file access flags
  • Verified 27 @JavascriptInterface methods in JS bridge
  • Sanitized logs
  • Configured network_security_config.xml (Lichess certificate pinning + CT)
  • Tapjacking protection
  • Non-blocking RootDetector
  • SafetyNet not applied (offline application, no backend)

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2. Notification Bar — Three-State Model

The foreground service notification used to display live engine metrics:

[Old]  Regalia · Stockfish 18 · depth 22 · 1,840 kN/s

That was useful for engine debugging, but noisy for end users who don't think
in plies or kilonodes-per-second. v1.0.1 collapses it to three states:

State	Trigger	Notification Text
Ready	Engine idle, last bestmove received	Ready / 就绪
Analyzing	go sent, no bestmove yet	Analyzing… / 分析中…
Error	Engine output starts with Unexpected or returns empty	Engine error: <msg> (truncated to 80 chars)

The notification retains its other v1.0.1 properties:

• 📌 Non-removable — setOngoing(true) + FLAG_NO_CLEAR.
• 👆 Click-to-open — PendingIntent launches MainActivity.
• 🔕 Silent — setOnlyAlertOnce(true) + setShowWhen(false).
• 🏠 Local-only — setLocalOnly(true), no remote mirroring.

// EngineService.java — buildNotification()
Notification n = new NotificationCompat.Builder(this, CHANNEL_ID)
    .setContentTitle(getString(R.string.app_name))
    .setContentText(getString(R.string.notif_ready))      // ← was depth/nps
    .setSmallIcon(R.drawable.ic_stat_chess)
    .setOngoing(true)
    .setOnlyAlertOnce(true)
    .setShowWhen(false)
    .setLocalOnly(true)
    .setCategory(NotificationCompat.CATEGORY_SERVICE)
    .setContentIntent(openAppIntent)
    .build();

Note

On Android 14+, the user can still dismiss the notification via the
notification shade long-press menu — the OS overrides setOngoing at that
level. The foreground service itself continues running. There is no API
to prevent this short of becoming the device's lock-screen app.

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3. Undo Auto-Select Fix

Symptom

After pressing Undo, the previously-moved piece was supposed to be
auto-selected so the user could continue exploring lines. In practice, nothing
got selected — the highlight never appeared.

Root Cause

// BROKEN — read the wrong field off the previous state
const prev = stateHistory[stateHistory.length - 1];
const from = prev.lastMove.from;   // ← this is the move BEFORE the one being undone

prev.lastMove is the last move recorded inside the previous state — i.e.,
the move before the one being undone. That square, after restoring, is
usually empty or holds the opponent's piece. The subsequent
pieceAtFrom.color === playerColor check silently failed, so the select call
never fired.

Fix

Capture the move that is actually being undone before popping the
state stack, then use its .from:

const moveBeingUndone = current.lastMove;       // ← the move we're about to rewind
stateHistory.pop();
const restored = stateHistory[stateHistory.length - 1];
applyState(restored);
const fromSq = moveBeingUndone.from;

const pieceAtFrom = board[fromSq];

if (pieceAtFrom && pieceAtFrom.color === restored.playerColor) {

selectSquare(fromSq);

HapticManager.fire('PIECE_SELECT');   // haptic for consistency with manual taps

}

The dead fallback that used to select lastMove.to (the wrong square,
opponent's piece) was removed entirely.

Verification Matrix

Scenario	Expected	Result
Single undo from move 10 → 9	Piece on its pre-move square is highlighted	✅
Consecutive undo 10 → 9 → 8 → 7	Each press re-highlights the correct piece	✅
Tap empty square after auto-select	Selection cleared	✅
Tap another own piece after auto-select	Selection switches to that piece	✅
Undo all the way back to start position	No piece highlighted (none has moved)	✅

The full license texts are included in the source tarball under
LICENSE-* files. End users redistributing the APK must comply with the
GPL v3 terms covering the Stockfish engine.

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Regalia v1.0.1 — refined, not rewritten.

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This discussion was created from the release v1.0.1.