[zfdang]

Summary of Improvements

This PR delivers a comprehensive, systematic overhaul of the codebase across accessibility core, concurrency and thread safety, UI lifecycle & memory management, security & OS compatibility, and unit test coverage based on the multi-agent code review findings.

Each issue is resolved in an individual, atomic commit:

1. Build Configuration, Resources & Signing Security (4cb8775)

• Preserve Pinyin4j Resource: Removed resources { excludes += ['pinyindb/*'] } from app/build.gradle so the dictionary database is bundled in release APKs, fixing silent failure in pinyin sorting.
• Secure Keystore & Credentials: Keystore and passwords are now loaded strictly from environment variables or local.properties, removing plaintext secrets from gradle.properties.
• R8 / ProGuard Keep Rules: Added retain rules in proguard-rules.pro for line number attributes, serializable data models, and pinyin4j.

2. Privacy Disclosure & Accessibility Configuration (00eb172)

• Affirmative User Consent: Added mSetting.isDisclosureAccepted() gate in resumeSkipAdAfterWakeup() and startSkipAdProcess() so the background service remains idle after device reboot/wake until the user agrees to the in-app disclosure.
• Accessibility Service Config: Updated accessibility_service_config.xml feedback type to feedbackGeneric and removed unused flagRetrieveInteractiveWindows.

3. Accessibility Node Recycling & Overlay IPC Optimization (f13219f)

• Binder Token Recycling: Wrapped all node traversal in findAllNode() and dumpChildNodes() in try-finally blocks that guarantee every AccessibilityNodeInfo is recycled immediately after extraction.
• Precomputed Node Outlines: Introduced NodeOutlineData to cache node bounds, area, and metadata in Java heap memory. Sorting outlines no longer invokes native Binder roundtrips on every comparison.
• Gated Verbose Logging: Debug-level window dump logs are protected by if (BuildConfig.DEBUG).

4. BroadcastReceivers & Package Scheme Registration (95ac160)

• Data Scheme Filter: Added actions.addDataScheme("package") to PackageChangeReceiver's filter so Android OS forwards package addition and removal events properly.
• Export Flag for API 33+: Explicitly registered dynamic receivers with ContextCompat.RECEIVER_EXPORTED.
• Include Custom-Ruled Apps: Augmented target package checking to inspect configured widgets and positions, ensuring non-launcher apps with custom rules are triggered.

5. Settings Concurrency & Defensive Copying (7655dd4)

• Thread-Safe Settings Singleton: Added double-checked locking lazy initialization for Settings.getInstance().
• Defensive Copying & Synchronization: Synchronized getters and setters for rule collections and returned unmodifiable/defensive deep copies.
• Corrupted JSON Resilience: Added robust exception handling during JSON deserialization to fall back safely to empty collections instead of crashing or leaking partial state.
• Volatile Field Flags: Marked notification and duration preferences volatile.

6. Robust Rule Matching & Model Hardening (286b582)

• Model Equality & Copying: Implemented robust equals(), hashCode(), toString(), and null-safe copy constructors in PackagePositionDescription and PackageWidgetDescription.
• Position Future Management: Tracked scheduled position click retry tasks via positionClickFuture and cancelled them upon process reset.
• Case-Insensitive & Unicode Matching: Enhanced SkipAdRules.parseKeywords() with Unicode whitespace regex ((?U)\\s+), added case-insensitive matching, and stripped zero-width characters (e.g. \u200B, \uFEFF).
• Non-Empty Bounds Validation: Guaranteed that rules with empty bounds (0,0,0,0) do not match offscreen nodes at (0,0,0,0).

7. Clipboard, Overlay & Dialog Lifecycle Safety (e3eb293)

• Safe Clipboard Pasting: Used clipData.getItemAt(0).coerceToText(context) with null and item count checks.
• Android 13+ Clipboard Toast: Suppressed custom copy toast on Android 13+ (TIRAMISU) to prevent system duplicate toast notifications.
• Isolated Overlay Removal: Handled view removal in isolated try-catch blocks with isAttachedToWindow() checks.
• Saved State Preservation: Avoided overwriting edited rules across configuration/rotation changes.
• Service Notification: Dispatched ACTION_REFRESH_CUSTOMIZED_ACTIVITY after saving rules.

8. UI Memory Leak Prevention & MVVM Architecture (141cd08)

• Dialog Leak Prevention: Retained whitelistDialog instance and safely dismissed it in SettingsFragment.onDestroyView().
• Cleaned Layouts: Removed dead fragment_settings.xml and bottom padding reflection hack.
• Clean Preference Pruning: Replaced manual iterative pruning with retainAll().
• MVVM Encapsulation: Encapsulated MutableLiveData within HomeViewModel and exposed read-only LiveData, moving service status refreshing logic into the ViewModel.
• Accessibility Attributes: Added missing android:contentDescription to action buttons and status icons.

9. Comprehensive Unit Test Coverage (d1dc434)

• Added PackagePositionDescriptionTest verifying constructors, equality, hash code, and string representation.
• Added SettingsTest under Robolectric testing singleton isolation, defensive copying, JSON corruption handling, and preferences persistence.
• Expanded SkipAdRulesTest with Unicode ideographic space parsing, case insensitivity, zero-width evasion characters, and empty bounds filtering.

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Verification

• Ran ./gradlew assembleDebug (Passed).
• Ran ./gradlew testDebugUnitTest (All passed).
• Ran ./gradlew test (Debug and Release test suites passed: 53 tasks executed/up-to-date, 0 failures).