Code cleanup, threading fixes, and deprecation removal

.gitignore

@@ -26,3 +26,6 @@ Thumbs.db
 # Logs
 *.log
 github-release.md
+
+# Local Claude instructions (not checked in)
+CLAUDE.local.md

CLAUDE.md

@@ -97,7 +97,7 @@ When bumping a version, update all of these:
 1. `app/build.gradle.kts` — `versionCode` and `versionName`
 2. `CHANGELOG.md` — Add new version entry with date
 3. `fastlane/metadata/android/en-US/changelogs/{versionCode}.txt` — Short changelog for F-Droid/store
-4. `github-release.md` — Release notes for GitHub releases
+4. `github-release.md` — Release notes for GitHub releases (gitignored, copy manually)
 5. Tag the release: `git tag v{versionName}`
 6. Update fdroiddata YAML — see rules below
 
@@ -143,9 +143,13 @@ app/src/main/java/com/translander/
 │   └── SettingsRepository.kt # DataStore preferences
 ├── transcribe/           # Voice message transcription
 │   ├── AudioDecoder.kt       # Decode audio files to 16kHz PCM
-│   ├── AudioMonitorService.kt # Watch folders for new audio
+│   ├── AudioMonitorService.kt # Watch folders for new audio (specialUse FGS)
 │   ├── TranscribeActivity.kt # UI for shared/opened audio
 │   └── TranscribeManager.kt  # Extensible trigger system
+├── notification/
+│   └── ServiceAlertNotification.kt # Boot failure notification (Android 14+)
+├── util/
+│   └── BootCompatHelper.kt   # Android 14+ FGS restriction checks
 └── k2fsa/sherpa/onnx/    # Native ONNX bindings
 ```
 
@@ -220,6 +224,30 @@ RecognizerManager.transcribe() (reuses existing recognition)
 ### UI Location
 Settings → Voice Message Transcription → Monitor Downloads toggle
 
+## Android 14+ Boot Restrictions
+
+Android 14+ blocks starting foreground services with restricted types (`microphone`, `dataSync`) from `BOOT_COMPLETED`. The app handles this via:
+
+1. **BootCompatHelper** — Checks `Build.VERSION.SDK_INT < UPSIDE_DOWN_CAKE` (API 34)
+2. **ServiceAlertNotification** — Shows persistent notification prompting user to open app
+3. **SettingsActivity.onResume()** — Restarts services when user opens app
+
+### FGS Type for AudioMonitorService
+
+Uses `specialUse` instead of `dataSync` because:
+- `dataSync` has 6-hour timeout on Android 15+ (targetSdk 35)
+- `specialUse` has no time limit
+
+**Google Play requirement:** When submitting, provide justification for `FOREGROUND_SERVICE_SPECIAL_USE`:
+> Monitors user-selected folders for voice messages to enable offline transcription. User-initiated, runs only while enabled in Settings.
+
+**Manifest property:**
+```xml
+<property
+    android:name="android.app.PROPERTY_SPECIAL_USE_FGS_SUBTYPE"
+    android:value="Monitors user-selected folders for voice messages..."/>
+```
+
 ## Hotwords Feature (BLOCKED)
 
 Sherpa-onnx supports hotwords boosting but **NOT for Parakeet TDT models**:
@@ -247,7 +275,7 @@ OfflineRecognizerConfig(
 - RECORD_AUDIO
 - SYSTEM_ALERT_WINDOW (floating button)
 - FOREGROUND_SERVICE_MICROPHONE
-- FOREGROUND_SERVICE_DATA_SYNC (audio monitor)
+- FOREGROUND_SERVICE_SPECIAL_USE (audio monitor — no timeout on Android 15+)
 - BIND_ACCESSIBILITY_SERVICE
 - POST_NOTIFICATIONS
 - INTERNET (model download)

app/src/main/AndroidManifest.xml

@@ -68,6 +68,7 @@
         <activity
             android:name=".transcribe.TranscribeActivity"
             android:exported="true"
+            android:configChanges="orientation|screenSize|screenLayout|keyboardHidden"
             android:theme="@style/Theme.VoiceKeyboard.Dialog">
 
             <!-- Share intent from apps like WhatsApp -->

app/src/main/java/com/translander/asr/AudioRecorder.kt

@@ -5,6 +5,7 @@ import android.media.AudioFormat
 import android.media.AudioRecord
 import android.media.MediaRecorder
 import android.util.Log
+import java.util.concurrent.atomic.AtomicBoolean
 
 class AudioRecorder {
 
@@ -16,7 +17,7 @@ class AudioRecorder {
     }
 
     private var audioRecord: AudioRecord? = null
-    private var isRecording = false
+    private val isRecording = AtomicBoolean(false)
     private val audioBuffer = mutableListOf<Short>()
 
     private val bufferSize = AudioRecord.getMinBufferSize(
@@ -27,7 +28,7 @@ class AudioRecorder {
 
     @SuppressLint("MissingPermission")
     fun startRecording() {
-        if (isRecording) return
+        if (!isRecording.compareAndSet(false, true)) return
 
         audioBuffer.clear()
 
@@ -47,12 +48,11 @@ class AudioRecorder {
                 return
             }
 
-            isRecording = true
             audioRecord?.startRecording()
 
             val buffer = ShortArray(bufferSize / 2)
 
-            while (isRecording) {
+            while (isRecording.get()) {
                 val readCount = audioRecord?.read(buffer, 0, buffer.size) ?: 0
                 if (readCount > 0) {
                     synchronized(audioBuffer) {
@@ -78,12 +78,12 @@ class AudioRecorder {
             audioRecord?.release()
             audioRecord = null
         } finally {
-            isRecording = false
+            isRecording.set(false)
         }
     }
 
     fun stopRecording(): ShortArray {
-        isRecording = false
+        isRecording.set(false)
 
         try {
             audioRecord?.stop()
@@ -99,7 +99,7 @@ class AudioRecorder {
     }
 
     fun release() {
-        isRecording = false
+        isRecording.set(false)
         try {
             audioRecord?.stop()
         } catch (e: IllegalStateException) {
@@ -110,5 +110,5 @@ class AudioRecorder {
         audioBuffer.clear()
     }
 
-    fun isRecording(): Boolean = isRecording
+    fun isRecording(): Boolean = isRecording.get()
 }

app/src/main/java/com/translander/asr/DictionaryManager.kt

@@ -30,12 +30,22 @@ class DictionaryManager(private val context: Context) {
         val caseSensitive: Boolean = false
     )
 
+    /** Compiled regex pattern paired with replacement string */
+    private data class CompiledRule(
+        val pattern: Regex,
+        val replacement: String
+    )
+
     private val rulesFile = File(context.filesDir, RULES_FILE)
     private val mutex = Mutex()
 
     private val _rules = MutableStateFlow<List<ReplacementRule>>(emptyList())
     val rules: StateFlow<List<ReplacementRule>> = _rules
 
+    // Cached compiled regex patterns for performance
+    @Volatile
+    private var compiledRules: List<CompiledRule> = emptyList()
+
     init {
         // Load rules synchronously on init to ensure they're available immediately
         loadRulesSync()
@@ -64,10 +74,24 @@ class DictionaryManager(private val context: Context) {
                 )
             }
             _rules.value = loadedRules
+            rebuildCompiledRules(loadedRules)
             Log.i(TAG, "Loaded ${loadedRules.size} replacement rules")
         } catch (e: Exception) {
             Log.e(TAG, "Failed to load rules", e)
             _rules.value = emptyList()
+            compiledRules = emptyList()
+        }
+    }
+
+    /** Rebuild cached compiled regex patterns when rules change */
+    private fun rebuildCompiledRules(rules: List<ReplacementRule>) {
+        compiledRules = rules.map { rule ->
+            val pattern = if (rule.caseSensitive) {
+                "\\b${Regex.escape(rule.from)}\\b".toRegex()
+            } else {
+                "\\b${Regex.escape(rule.from)}\\b".toRegex(RegexOption.IGNORE_CASE)
+            }
+            CompiledRule(pattern, rule.to)
         }
     }
 
@@ -106,6 +130,7 @@ class DictionaryManager(private val context: Context) {
         currentRules.removeAll { it.from.equals(from, ignoreCase = true) }
         currentRules.add(ReplacementRule(from.trim(), to.trim(), caseSensitive))
         _rules.value = currentRules
+        rebuildCompiledRules(currentRules)
         saveRules()
         Log.i(TAG, "Added rule: '$from' -> '$to'")
     }
@@ -118,6 +143,7 @@ class DictionaryManager(private val context: Context) {
         val removed = currentRules.removeAll { it.from == from }
         if (removed) {
             _rules.value = currentRules
+            rebuildCompiledRules(currentRules)
             saveRules()
             Log.i(TAG, "Removed rule for: '$from'")
         }
@@ -126,18 +152,15 @@ class DictionaryManager(private val context: Context) {
     /**
      * Apply all replacement rules to the given text.
      * Uses whole-word matching with word boundaries.
+     * Uses pre-compiled regex patterns for performance.
      */
     fun applyReplacements(text: String): String {
-        if (text.isBlank() || _rules.value.isEmpty()) return text
+        val rules = compiledRules  // Capture volatile reference
+        if (text.isBlank() || rules.isEmpty()) return text
 
         var result = text
-        for (rule in _rules.value) {
-            val regex = if (rule.caseSensitive) {
-                "\\b${Regex.escape(rule.from)}\\b".toRegex()
-            } else {
-                "\\b${Regex.escape(rule.from)}\\b".toRegex(RegexOption.IGNORE_CASE)
-            }
-            result = result.replace(regex, rule.to)
+        for (rule in rules) {
+            result = result.replace(rule.pattern, rule.replacement)
         }
         return result
     }
@@ -189,8 +212,10 @@ class DictionaryManager(private val context: Context) {
                     currentRules.add(newRule)
                 }
                 _rules.value = currentRules
+                rebuildCompiledRules(currentRules)
             } else {
                 _rules.value = importedRules
+                rebuildCompiledRules(importedRules)
             }
             saveRules()
             Log.i(TAG, "Imported ${importedRules.size} rules (merge=$merge)")
@@ -204,6 +229,7 @@ class DictionaryManager(private val context: Context) {
      */
     suspend fun clearAllRules() = mutex.withLock {
         _rules.value = emptyList()
+        compiledRules = emptyList()
         saveRules()
         Log.i(TAG, "Cleared all rules")
     }

app/src/main/java/com/translander/asr/ModelManager.kt

@@ -162,29 +162,29 @@ class ModelManager(private val context: Context) {
 
     private suspend fun downloadFile(url: String, targetFile: File, onProgress: (Int) -> Unit) {
         val request = Request.Builder().url(url).build()
-        val response = httpClient.newCall(request).execute()
-
-        if (!response.isSuccessful) {
-            throw java.io.IOException("Download failed: ${response.code}")
-        }
+        httpClient.newCall(request).execute().use { response ->
+            if (!response.isSuccessful) {
+                throw java.io.IOException("Download failed: ${response.code}")
+            }
 
-        val body = response.body ?: throw java.io.IOException("Empty response body")
-        val contentLength = body.contentLength()
+            val body = response.body ?: throw java.io.IOException("Empty response body")
+            val contentLength = body.contentLength()
 
-        body.byteStream().use { input ->
-            FileOutputStream(targetFile).use { output ->
-                val buffer = ByteArray(8192)
-                var bytesRead: Int
-                var totalBytesRead = 0L
+            body.byteStream().use { input ->
+                FileOutputStream(targetFile).use { output ->
+                    val buffer = ByteArray(8192)
+                    var bytesRead: Int
+                    var totalBytesRead = 0L
 
-                while (input.read(buffer).also { bytesRead = it } != -1) {
-                    coroutineContext.ensureActive()
-                    output.write(buffer, 0, bytesRead)
-                    totalBytesRead += bytesRead
+                    while (input.read(buffer).also { bytesRead = it } != -1) {
+                        coroutineContext.ensureActive()
+                        output.write(buffer, 0, bytesRead)
+                        totalBytesRead += bytesRead
 
-                    if (contentLength > 0) {
-                        val progress = ((totalBytesRead * 100) / contentLength).toInt()
-                        onProgress(progress)
+                        if (contentLength > 0) {
+                            val progress = ((totalBytesRead * 100) / contentLength).toInt()
+                            onProgress(progress)
+                        }
                     }
                 }
             }

app/src/main/java/com/translander/asr/ParakeetRecognizer.kt

@@ -72,7 +72,7 @@ class ParakeetRecognizer(
         }
     }
 
-    fun transcribe(audioData: ShortArray, @Suppress("UNUSED_PARAMETER") languageCode: String? = null): String? {
+    fun transcribe(audioData: ShortArray): String? {
         val rec = recognizer ?: return null
 
         if (audioData.isEmpty()) {