fix(debug): Fix deadlock risk, missing IO dispatcher, and thread safety in session manager

Replace sessions.first() inside fsMutex.withLock with synchronous volatile

read to avoid potential deadlock. Wrap file deletions in IO dispatcher.

Log partial delete failures. Make pendingAutoZips thread-safe via

Collections.synchronizedSet. Add test for ext/cache same-basename IDs.

app/src/main/java/eu/darken/capod/common/debug/recording/core/DebugSessionManager.kt

@@ -15,7 +15,6 @@ import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.MutableSharedFlow
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.combine
-import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.flow.onStart
 import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.CancellationException
@@ -43,7 +42,7 @@ class DebugSessionManager @Inject constructor(
     private val zippingIds = MutableStateFlow<Set<String>>(emptySet())
     private val failedZipIds = MutableStateFlow<Set<String>>(emptySet())
     private val refreshTrigger = MutableSharedFlow<Unit>(extraBufferCapacity = 1)
-    private val pendingAutoZips = mutableSetOf<String>()
+    private val pendingAutoZips: MutableSet<String> = java.util.Collections.synchronizedSet(mutableSetOf())
 
     val recorderState: Flow<RecorderModule.State> get() = recorderModule.state
 
@@ -160,10 +159,11 @@ class DebugSessionManager @Inject constructor(
         refreshTrigger.tryEmit(Unit)
     }
 
+    private fun activeSessionId(): String? = recorderModule.currentLogDir?.let { deriveSessionId(it) }
+
     suspend fun zipSession(sessionId: String): File = fsMutex.withLock {
-        val activeRecording = sessions.first().filterIsInstance<DebugSession.Recording>()
-            .firstOrNull { it.id == sessionId }
-        require(activeRecording == null) { "Cannot zip an active recording session" }
+        // Do NOT call sessions.first() here — deadlock risk with fsMutex
+        require(activeSessionId() != sessionId) { "Cannot zip an active recording session" }
 
         val (dir, existingZip) = findSessionFiles(sessionId)
 
@@ -185,15 +185,19 @@ class DebugSessionManager @Inject constructor(
     }
 
     suspend fun deleteSession(sessionId: String) = fsMutex.withLock {
-        val currentSessions = sessions.first()
-        val recording = currentSessions.filterIsInstance<DebugSession.Recording>()
-            .firstOrNull { it.id == sessionId }
-        require(recording == null) { "Cannot delete an active recording session" }
+        // Do NOT call sessions.first() here — deadlock risk with fsMutex
+        require(activeSessionId() != sessionId) { "Cannot delete an active recording session" }
         require(sessionId !in zippingIds.value) { "Cannot delete a session that is being compressed" }
 
-        val (dir, zip) = findSessionFiles(sessionId)
-        dir?.deleteRecursively()
-        zip?.delete()
+        withContext(dispatcherProvider.IO) {
+            val (dir, zip) = findSessionFiles(sessionId)
+            if (dir?.deleteRecursively() == false) {
+                log(TAG, WARN) { "Failed to fully delete session dir: ${dir.path}" }
+            }
+            if (zip?.delete() == false) {
+                log(TAG, WARN) { "Failed to delete session zip: ${zip.path}" }
+            }
+        }
         failedZipIds.update { it - sessionId }
 
         log(TAG) { "Deleted session: $sessionId" }
@@ -201,24 +205,23 @@ class DebugSessionManager @Inject constructor(
     }
 
     suspend fun deleteAllSessions() = fsMutex.withLock {
-        val activeDir = recorderModule.state.first().currentLogDir
+        val activeDir = recorderModule.currentLogDir
         val currentlyZipping = zippingIds.value
-        for (dir in recorderModule.getLogDirectories()) {
-            if (!dir.exists()) continue
-            for (entry in dir.listFiles() ?: emptyArray()) {
-                if (entry == activeDir) {
-                    log(TAG) { "Skipping active session dir: $entry" }
-                    continue
-                }
-                val entryId = deriveSessionId(entry)
-                if (entryId in currentlyZipping) {
-                    log(TAG) { "Skipping zipping session: $entry" }
-                    continue
-                }
-                if (entry.isDirectory) {
-                    entry.deleteRecursively()
-                } else {
-                    entry.delete()
+        withContext(dispatcherProvider.IO) {
+            for (dir in recorderModule.getLogDirectories()) {
+                if (!dir.exists()) continue
+                for (entry in dir.listFiles() ?: emptyArray()) {
+                    if (entry == activeDir) {
+                        log(TAG) { "Skipping active session dir: $entry" }
+                        continue
+                    }
+                    val entryId = deriveSessionId(entry)
+                    if (entryId in currentlyZipping) {
+                        log(TAG) { "Skipping zipping session: $entry" }
+                        continue
+                    }
+                    val deleted = if (entry.isDirectory) entry.deleteRecursively() else entry.delete()
+                    if (!deleted) log(TAG, WARN) { "Failed to delete: ${entry.path}" }
                 }
             }
         }

app/src/main/java/eu/darken/capod/common/debug/recording/core/RecorderModule.kt

@@ -33,6 +33,10 @@ class RecorderModule @Inject constructor(
     private val installId: InstallId,
 ) {
 
+    @Volatile
+    internal var currentLogDir: File? = null
+        private set
+
     private val triggerFile = try {
         File(context.getExternalFilesDir(null), FORCE_FILE)
     } catch (e: Exception) {
@@ -64,6 +68,8 @@ class RecorderModule @Inject constructor(
                         log(TAG, INFO) { "Build.Fingerprint: ${Build.FINGERPRINT}" }
                         log(TAG, INFO) { "BuildConfig.Versions: ${BuildConfigWrap.VERSION_DESCRIPTION}" }
 
+                        this@RecorderModule.currentLogDir = sessionDir
+
                         copy(
                             recorder = newRecorder,
                             currentLogDir = sessionDir,
@@ -76,6 +82,8 @@ class RecorderModule @Inject constructor(
                             log(TAG, ERROR) { "Failed to delete trigger file" }
                         }
 
+                        this@RecorderModule.currentLogDir = null
+
                         copy(
                             recorder = null,
                             currentLogDir = null,

app/src/test/java/eu/darken/capod/common/debug/recording/core/DebugSessionManagerTest.kt

@@ -199,6 +199,23 @@ class DebugSessionManagerTest : BaseTest() {
             // Verify the session IS a Recording — the manager would reject zip/delete calls for this
         }
 
+        @Test
+        fun `ext and cache sessions with same basename have different IDs`() {
+            val cacheLogsDir = File(tempDir, "cache/debug/logs").also { it.mkdirs() }
+            val extDir = File(externalLogsDir, "capod_1.0_1700000000000_abcd1234").also { it.mkdirs() }
+            File(extDir, "core.log").writeText("external log")
+            val cacheDir = File(cacheLogsDir, "capod_1.0_1700000000000_abcd1234").also { it.mkdirs() }
+            File(cacheDir, "core.log").writeText("cache log")
+
+            val sessions = DebugSessionManager.scanSessions(
+                logDirectories = listOf(externalLogsDir, cacheLogsDir),
+            )
+
+            sessions shouldHaveSize 2
+            val ids = sessions.map { it.id }.toSet()
+            ids shouldBe setOf("ext:capod_1.0_1700000000000_abcd1234", "cache:capod_1.0_1700000000000_abcd1234")
+        }
+
         @Test
         fun `zipping session should not be deleted`() {
             val sessionDir = File(externalLogsDir, "capod_1.0_1700000000000_abcd1234").also { it.mkdirs() }