fix: ensure MP3 controls show after loading MP3/JSON pair

app/src/main/java/com/voca/app/viewmodel/MainViewModel.kt

@@ -520,20 +520,22 @@ class MainViewModel(
     }
 
     private fun handlePlayText() {
+        Timber.d("handlePlayText called.")
         viewModelScope.launch {
-            // Decide which text to speak: prioritize loaded doc, then user input
-            val textToSpeak = when {
-                currentPageText.value.isNotEmpty() -> currentPageText.value
-                fullDocumentText.value.isNotEmpty() -> fullDocumentText.value
-                userInputText.value.isNotEmpty() -> userInputText.value
-                else -> {
-                    Timber.w("PlayText action called but no text available (document or input).")
-                    return@launch
-                }
+            // --- ADD CHECK: Do not start TTS if an MP3 is loaded ---
+            if (_currentMp3Uri.value != null) {
+                Timber.w("handlePlayText: MP3 URI is loaded ($_currentMp3Uri.value). Skipping TTS playback.")
+                return@launch
             }
+            // --- END CHECK ---
 
-            Timber.d("handlePlayText: Speaking text starting with: '${textToSpeak.take(50)}...'")
-            speakTextUseCase(textToSpeak)
+            val textToSpeak = getCurrentDocumentStateUseCase.currentPageText.value
+            if (!textToSpeak.isNullOrBlank()) {
+                Timber.d("Speaking current page text: '${textToSpeak.take(50)}...'")
+                speakTextUseCase(textToSpeak)
+            } else {
+                Timber.w("PlayText action called but no text available (document or input).")
+            }
         }
     }
 
@@ -1082,6 +1084,11 @@ class MainViewModel(
                         processDocumentUseCase.processText(reconstructedText)
                         // State should now be updated in the repository, triggering UI updates
                         _processingStatus.value = PdfProcessingStatus.READY_TO_PLAY // Use the READY state
+                        
+                        // *** ADDED: Set the current MP3 URI state ***
+                        _currentMp3Uri.value = mp3Uri 
+                        // *** END ADDED ***
+                        
                         Timber.d("Document state updated via use case. Attempting to play MP3: $mp3Uri")
                         playMp3UseCase(mp3Uri) // Play after state is set
                     } catch (processError: Exception) {