deepvoice_client/lib/modules/translation/controllers/translation_controller.dart

import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'dart:async';
import '../../../data/services/azure_asr_service.dart';
import '../../../data/services/volcano_translation_service.dart';
import '../../../data/services/volcano_tts_api_service.dart';
// import '../../../core/utils/logger.dart';

class TranslationController extends GetxController {
  // Services
  final AzureAsrService _asrService = Get.find<AzureAsrService>();
  final VolcanoTranslationService _translationService = Get.find<VolcanoTranslationService>();
  final VolcanoTtsApiService _ttsService = Get.find<VolcanoTtsApiService>();

  // State variables
  final isRecognizing = false.obs;
  final isTranslating = false.obs;
  final isTtsEnabled = true.obs;
  final recognizedText = ''.obs;
  final translatedText = ''.obs;
  final sourceLanguage = '中文 (Chinese)'.obs;
  final targetLanguage = '英语 (English)'.obs;
  final translationHistory = <TranslationItem>[].obs;
  
  // Current translation item
  TranslationItem? currentItem;
  
  // Subscription for recognition stream
  StreamSubscription? _recognitionSubscription;
  
  // Scroll controller for ListView
  final ScrollController scrollController = ScrollController();
  
  // Timer for debouncing translation requests
  Timer? _translationDebounceTimer;

  @override
  void onInit() {
    super.onInit();
    
    // Initialize the translation service
    _initTranslationService();
    
    // Start voice recognition automatically when the page is loaded
    startRecognition();
  }

  @override
  void onClose() {
    stopRecognition();
    _recognitionSubscription?.cancel();
    _translationDebounceTimer?.cancel();
    scrollController.dispose();
    super.onClose();
  }
  
  // Initialize the translation service
  Future<void> _initTranslationService() async {
    try {
      await _translationService.initialize();
    } catch (e) {
      Get.snackbar(
        'Error',
        'Failed to initialize translation service: ${e.toString()}',
        snackPosition: SnackPosition.BOTTOM,
      );
    }
  }

  // Toggle TTS feature
  void toggleTts() {
    isTtsEnabled.toggle();
  }

  // Start voice recognition
  Future<void> startRecognition() async {
    if (isRecognizing.value) return;
    
    try {
      // Initialize a new translation item
      currentItem = TranslationItem(
        sourceText: '',
        translatedText: '',
        sourceLanguage: sourceLanguage.value,
        targetLanguage: targetLanguage.value,
        timestamp: DateTime.now(),
      );
      
      // Start the voice recognition service
      final success = await _asrService.startContinuousRecognition();
      
      if (success) {
        isRecognizing.value = true;
        
        // Reset the recognized text
        recognizedText.value = '';
        translatedText.value = '';
        
        // Listen for recognition events
        _recognitionSubscription = _asrService.recognitionStream?.listen((event) {
          switch (event.type) {
            case RecognitionEventType.finalResult:
              if (event.text.isNotEmpty) {
                handleFinalResult(event.text);
              }
              break;
            case RecognitionEventType.recognizing:
              // Update the UI with intermediate results
              if (event.text.isNotEmpty) {
                handleIntermediateResult(event.text);
              }
              break;
            case RecognitionEventType.error:
              Get.snackbar(
                'Error',
                'Recognition error: ${event.error}',
                snackPosition: SnackPosition.BOTTOM,
              );
              break;
            default:
              break;
          }
        });
      } else {
        throw Exception('Failed to start continuous recognition');
      }
    } catch (e) {
      isRecognizing.value = false;
      Get.snackbar(
        'Error',
        'Failed to start voice recognition: ${e.toString()}',
        snackPosition: SnackPosition.BOTTOM,
      );
    }
  }

  // Stop voice recognition
  Future<void> stopRecognition() async {
    if (!isRecognizing.value) return;
    
    try {
      await _asrService.stopContinuousRecognition();
      _recognitionSubscription?.cancel();
      _recognitionSubscription = null;
      isRecognizing.value = false;
      
      // 添加当前项到历史（如果有内容）
      finalizeCurrentItem();
      
      // 重置当前显示的文本
      recognizedText.value = '';
      translatedText.value = '';
    } catch (e) {
      Get.snackbar(
        'Error',
        'Failed to stop voice recognition: ${e.toString()}',
        snackPosition: SnackPosition.BOTTOM,
      );
    }
  }
  
  // Handle intermediate recognition result
  void handleIntermediateResult(String text) {
    if (text.isEmpty) return;
    
    // 如果当前没有活跃的翻译项，创建一个新的
    if (currentItem == null) {
      currentItem = TranslationItem(
        sourceText: text,
        translatedText: '',
        sourceLanguage: sourceLanguage.value,
        targetLanguage: targetLanguage.value,
        timestamp: DateTime.now(),
      );
    } else {
      // 更新当前翻译项
      currentItem!.sourceText = text;
    }
    
    // 实时更新识别文本
    recognizedText.value = text;
    
    // Debounce translation requests to avoid too many API calls
    _translationDebounceTimer?.cancel();
    _translationDebounceTimer = Timer(const Duration(milliseconds: 300), () {
      translateText(text, isFinal: false);
    });
    
    // Scroll to the bottom to show the latest content
    _scrollToBottom();
  }
  
  // Handle final recognition result
  void handleFinalResult(String text) {
    if (text.isEmpty) return;
    
    // 更新当前翻译项（如果不存在则创建一个）
    if (currentItem == null) {
      currentItem = TranslationItem(
        sourceText: text,
        translatedText: '',
        sourceLanguage: sourceLanguage.value,
        targetLanguage: targetLanguage.value,
        timestamp: DateTime.now(),
      );
    } else {
      currentItem!.sourceText = text;
    }
    
    // 更新识别文本
    recognizedText.value = text;
    
    // 翻译最终结果 (添加到历史的逻辑已移至translateText方法)
    translateText(text, isFinal: true).then((_) {
      // 作为安全措施，确保当前项被添加到历史中
      // 这是为了处理translateText中可能因为条件不满足而没有添加到历史的情况
      finalizeCurrentItem();
    });
    
    // Scroll to the bottom to show the latest content
    _scrollToBottom();
  }
  
  // Finalize the current translation item and add it to history
  void finalizeCurrentItem() {
    if (currentItem != null && 
        currentItem!.sourceText.isNotEmpty && 
        currentItem!.translatedText.isNotEmpty &&
        !translationHistory.contains(currentItem)) {
      translationHistory.add(currentItem!);
      currentItem = null;
    }
  }

  // Handle voice recognition result (legacy method, kept for compatibility)
  void handleVoiceResult(String text) {
    handleFinalResult(text);
  }

  // Translate the recognized text
  Future<void> translateText(String text, {bool isFinal = true}) async {
    if (text.isEmpty) return;
    
    isTranslating.value = true;
    
    // 保存当前的翻译项引用，确保异步返回时更新正确的项
    final TranslationItem? itemToUpdate = currentItem;
    
    try {
      final result = await _translationService.translateText(
        text: text,
        sourceLanguage: sourceLanguage.value,
        targetLanguage: targetLanguage.value,
      );
      
      if (result != null) {
        // 实时更新翻译文本
        translatedText.value = result;
        
        // 确保更新的是发起翻译请求时的翻译项，而不是当前可能已经变化的翻译项
        if (itemToUpdate != null && itemToUpdate.sourceText == text) {
          itemToUpdate.translatedText = result;
          
          // 如果是最终结果，并且当前项仍然是发起请求时的项，则添加到历史
          if (isFinal && itemToUpdate == currentItem) {
            translationHistory.add(itemToUpdate);
            currentItem = null;  // 重要：将当前项设为null，表示已完成
            
            // 重置当前显示的文本，避免与历史项重复
            recognizedText.value = '';
            translatedText.value = '';
          }
          
          // Play TTS if enabled and this is a final result
          if (isTtsEnabled.value && isFinal) {
            playTranslatedText(result);
          }
        }
      }
    } catch (e) {
      Get.snackbar(
        'Error',
        'Translation failed: ${e.toString()}',
        snackPosition: SnackPosition.BOTTOM,
      );
    } finally {
      isTranslating.value = false;
    }
  }

  // Play the translated text using TTS
  Future<void> playTranslatedText(String text) async {
    if (text.isEmpty) return;
    
    try {
      await _ttsService.speakSingle(text);
    } catch (e) {
      Get.snackbar(
        'Error',
        'Failed to play translation: ${e.toString()}',
        snackPosition: SnackPosition.BOTTOM,
      );
    }
  }

  // Play a specific translation item
  Future<void> playTranslationItem(TranslationItem item) async {
    await playTranslatedText(item.translatedText);
  }
  
  // Scroll to the bottom of the list
  void _scrollToBottom() {
    if (scrollController.hasClients) {
      Future.delayed(const Duration(milliseconds: 100), () {
        scrollController.animateTo(
          scrollController.position.maxScrollExtent,
          duration: const Duration(milliseconds: 300),
          curve: Curves.easeOut,
        );
      });
    }
  }
}

// Model class for translation items
class TranslationItem {
  String sourceText;
  String translatedText;
  final String sourceLanguage;
  final String targetLanguage;
  final DateTime timestamp;

  TranslationItem({
    required this.sourceText,
    required this.translatedText,
    required this.sourceLanguage,
    required this.targetLanguage,
    required this.timestamp,
  });
}