import 'package:get/get.dart';
import 'package:flutter/material.dart';
import 'package:get_storage/get_storage.dart';
import 'dart:convert';
import '../../../data/services/volcano_ai_service.dart';
import '../../../data/services/volcano_tts_service.dart';
import '../models/message_model.dart';
import '../controllers/voice_input_controller.dart';
import 'package:flutter/services.dart';

class ChatController extends GetxController {
  String agentId = '';
  String agentName = '';
  String agentAvatar = '';
  String? agentSubtitle;
  String systemPrompt = '';
  String welcomeMessage = '';
  bool playVoiceOnEnter = false;

  final VolcanoAIService _aiService = VolcanoAIService();
  late final VolcanoTtsService _ttsService;
  static const String _storagePrefix = 'chat_history_';

  final messages = <Message>[].obs;
  final isLoading = false.obs;
  late final TextEditingController messageController;
  late final ScrollController scrollController;
  final _storage = GetStorage();

  // 用于存储当前正在流式生成的消息
  final RxString currentStreamMessage = ''.obs;
  Message? _currentAssistantMessage;
  String _pendingTtsText = '';
  static const int _minTtsLength = 20;
  bool _isDisposed = false;
  
  // 语音输入相关状态
  final isRecording = false.obs;
  final recordingText = ''.obs;
  final isVoiceInputVisible = false.obs;
  final isVoiceConnecting = true.obs;
  final isVoiceMuted = false.obs;
  Message? _currentVoiceMessage;

  @override
  void onInit() {
    super.onInit();
    messageController = TextEditingController();
    scrollController = ScrollController();
    _initTtsService();
    _initFromArguments();
    _initializeController();
    
    // 延迟生成问候语，确保页面已完全加载
    if (playVoiceOnEnter) {
      WidgetsBinding.instance.addPostFrameCallback((_) {
        if (!_isDisposed) {
          generateSimpleGreeting();
        }
      });
    }
  }

  void _initFromArguments() {
    try {
      final arguments = Get.arguments;
      if (arguments == null) {
        throw Exception('No arguments provided to ChatController');
      }

      final args = arguments as Map<String, dynamic>;
      agentId = args['agentId'] as String? ?? '';
      agentName = args['agentName'] as String? ?? 'Assistant';
      agentAvatar = args['agentAvatar'] as String? ?? 'assets/images/default_avatar.png';
      agentSubtitle = args['agentSubtitle'] as String?;
      systemPrompt = args['systemPrompt'] as String? ?? '';
      welcomeMessage = args['welcomeMessage'] as String? ?? 'Hello! How can I help you today?';
      playVoiceOnEnter = args['playVoiceOnEnter'] as bool? ?? false;

      if (agentId.isEmpty) {
        throw Exception('Invalid agent ID');
      }
    } catch (e) {
      debugPrint('🔴 Error initializing ChatController: $e');
      Get.back();  // 返回上一页
      Get.snackbar(
        'Error',
        'Failed to initialize chat: Invalid parameters',
        snackPosition: SnackPosition.BOTTOM,
      );
    }
  }

  void _initTtsService() {
    _ttsService = Get.find<VolcanoTtsService>();
    _ttsService.isEnabled.value = true;
  }

  Future<void> _initializeController() async {
    try {
      await _loadChatHistory();

      await _showWelcomeMessages();
    } catch (e) {
      Get.snackbar(
        'Error',
        'Failed to initialize chat: $e',
        snackPosition: SnackPosition.BOTTOM,
      );
    }
  }

  Future<void> _showWelcomeMessages() async {
    try {
      if (messages.isEmpty && agentName.isNotEmpty && playVoiceOnEnter) {
        // 只有 playVoiceOnEnter 为 true 时才生成动态问候语
        await _generatePersonalizedGreeting();
        // 保存聊天记录并立即滚动到底部
        await _saveChatHistory();
        _scrollToBottom();
      }
    } catch (e) {
      print('显示欢迎消息失败: $e');
      // 如果生成问候语失败，确保至少显示静态欢迎消息
      if (_ttsService.isEnabled.value) {
        _ttsService.speak(welcomeMessage);
      }
    }
  }

  Future<void> _generatePersonalizedGreeting() async {
    if (_isDisposed) return;

    String fullGreeting = '';
    try {
      currentStreamMessage.value = '';
      _currentAssistantMessage = Message(
        role: 'assistant',
        content: '',
        timestamp: DateTime.now(),
      );
      messages.add(_currentAssistantMessage!);

      // 构建用于生成个性化问候语的消息列表
      final greetingMessages = [
        {'role': 'system', 'content': systemPrompt},
        {
          'role': 'user',
          'content': '请根据你的身份和性格，用一句简短的话向我打个招呼，要体现你的特点，不要超过18个字。'
        },
      ];

      await for (final chunk in _aiService.sendMessageStream(
        messages: greetingMessages,
        systemPrompt: systemPrompt,
      )) {
        if (_isDisposed) break;

        // 更新消息内容
        currentStreamMessage.value += chunk;
        _updateAssistantMessage(currentStreamMessage.value);
        fullGreeting += chunk;
      }

      // 完整问候语生成完毕后，一次性播放
      if (!_isDisposed &&
          _ttsService.isEnabled.value &&
          fullGreeting.isNotEmpty) {
        await _ttsService.speak(fullGreeting);
      }
    } catch (e) {
      print('生成问候语失败: $e');
      // 移除未完成的消息
      if (_currentAssistantMessage != null) {
        messages.remove(_currentAssistantMessage);
      }
    } finally {
      if (!_isDisposed) {
        _currentAssistantMessage = null;
        currentStreamMessage.value = '';
      }
    }
  }

  @override
  void onClose() {
    _isDisposed = true;
    
    // 确保语音输入被停止
    stopVoiceInput();
    
    // 先停止所有正在进行的操作
    _ttsService.stop();
    currentStreamMessage.value = '';
    _currentAssistantMessage = null;
    _pendingTtsText = '';

    // 最后再处理控制器的销毁
    try {
      messageController.dispose();
    } catch (e) {
      debugPrint('Error disposing messageController: $e');
    }
    
    try {
      scrollController.dispose();
    } catch (e) {
      debugPrint('Error disposing scrollController: $e');
    }
    
    super.onClose();
  }

  Future<void> _loadChatHistory() async {
    try {
      final historyJson = _storage.read('${_storagePrefix}${agentId}');
      if (historyJson != null) {
        final List<dynamic> historyList = json.decode(historyJson);
        messages.value = historyList.map((item) => Message.fromJson(item)).toList();
        
        // 如果有历史消息，等待下一帧再滚动到底部
        if (messages.isNotEmpty) {
          WidgetsBinding.instance.addPostFrameCallback((_) {
            _scrollToBottom();
          });
        }
      }
    } catch (e) {
      Get.snackbar(
        'Error',
        'Failed to load chat history: $e',
        snackPosition: SnackPosition.BOTTOM,
      );
    }
  }

  Future<void> _saveChatHistory() async {
    try {
      final historyJson =
          json.encode(messages.map((msg) => msg!.toJson()).toList());
      await _storage.write('${_storagePrefix}${agentId}', historyJson);
    } catch (e) {
      Get.snackbar(
        'Error',
        'Failed to save chat history: $e',
        snackPosition: SnackPosition.BOTTOM,
      );
    }
  }

  void _scrollToBottom() {
    if (scrollController.hasClients) {
      scrollController.jumpTo(scrollController.position.maxScrollExtent);
    }
  }

  void _updateAssistantMessage(String content) {
    if (_currentAssistantMessage != null) {
      final index = messages.indexWhere((msg) =>
          msg.timestamp == _currentAssistantMessage?.timestamp &&
          msg.role == _currentAssistantMessage?.role);

      if (index != -1) {
        messages[index] = Message(
          role: 'assistant',
          content: content,
          timestamp: _currentAssistantMessage!.timestamp,
        );
        // 只在非初始化阶段滚动
        if (!playVoiceOnEnter || content.isNotEmpty) {
          _scrollToBottom();
        }
      }
    }
  }

  void clearMessage() {
    if (!_isDisposed && messageController.text.isNotEmpty) {
      messageController.clear();
    }
  }

  Future<void> sendMessage() async {
    if (_isDisposed) return;
    
    final text = messageController.text.trim();
    if (text.isEmpty) return;

    try {
      final userMessage = Message(
        role: 'user',
        content: text,
        timestamp: DateTime.now(),
      );
      messages.add(userMessage);
      clearMessage();
      await _saveChatHistory();
      _scrollToBottom();

      isLoading.value = true;
      try {
        currentStreamMessage.value = '';
        _currentAssistantMessage = Message(
          role: 'assistant',
          content: '',
          timestamp: DateTime.now(),
        );
        messages.add(_currentAssistantMessage!);
        _pendingTtsText = '';

        await for (final chunk in _aiService.sendMessageStream(
          messages: messages
              .map((m) => {
                    'role': m.role,
                    'content': m.content,
                  })
              .toList(),
          systemPrompt: systemPrompt,
        )) {
          if (_isDisposed) break;

          currentStreamMessage.value += chunk;
          _updateAssistantMessage(currentStreamMessage.value);

          // 累积文本并合成
          _pendingTtsText += chunk;
          if (!_isDisposed && _ttsService.isEnabled.value) {
            // 检查是否达到最小长度
            if (_pendingTtsText.length >= _minTtsLength) {
              // 找到最后一个句子结束的位置
              int lastSentenceEnd = _findLastSentenceEnd(_pendingTtsText);
              if (lastSentenceEnd > 0) {
                // 播放到最后一个句子结束的位置
                String textToSpeak =
                    _pendingTtsText.substring(0, lastSentenceEnd + 1);
                _ttsService.speak(textToSpeak);
                // 保留剩余的文本
                _pendingTtsText = _pendingTtsText.substring(lastSentenceEnd + 1);
              }
            }
          }
        }

        // 处理剩余的文本
        if (!_isDisposed &&
            _ttsService.isEnabled.value &&
            _pendingTtsText.isNotEmpty) {
          _ttsService.speak(_pendingTtsText);
        }
        _pendingTtsText = '';

        if (!_isDisposed) {
          await _saveChatHistory();
        }
      } catch (e) {
        if (!_isDisposed) {
          if (_currentAssistantMessage != null) {
            messages.remove(_currentAssistantMessage);
          }
          Get.snackbar(
            'Error',
            'Failed to get response from AI: $e',
            snackPosition: SnackPosition.BOTTOM,
          );
        }
      } finally {
        if (!_isDisposed) {
          _currentAssistantMessage = null;
          currentStreamMessage.value = '';
          isLoading.value = false;
        }
      }
    } catch (e) {
      print('发送消息失败: $e');
    }
  }

  int _findLastSentenceEnd(String text) {
    final sentenceEnds = [
      text.lastIndexOf('。'),
      text.lastIndexOf('！'),
      text.lastIndexOf('？'),
      text.lastIndexOf('.'),
      text.lastIndexOf('!'),
      text.lastIndexOf('?'),
    ];

    return sentenceEnds.reduce((max, pos) => pos > max ? pos : max);
  }

  Future<void> clearChat() async {
    try {
      messages.clear();
      await _storage.remove('${_storagePrefix}${agentId}');
      await _showWelcomeMessages();
    } catch (e) {
      Get.snackbar(
        'Error',
        'Failed to clear chat: $e',
        snackPosition: SnackPosition.BOTTOM,
      );
    }
  }

  void toggleTTS() {
    _ttsService.toggleEnabled();
  }

  /// 生成简单的问候语
  Future<void> generateSimpleGreeting() async {
    if (_isDisposed) return;

    try {
      currentStreamMessage.value = '';
      _currentAssistantMessage = Message(
        role: 'assistant',
        content: '',
        timestamp: DateTime.now(),
      );
      messages.add(_currentAssistantMessage!);

      // 构建用于生成问候语的消息列表
      final greetingMessages = [
        {'role': 'system', 'content': systemPrompt},
        {'role': 'user', 'content': '请用一句简短的话向我打个招呼，要体现你的特点，不要超过12个字。'},
      ];

      String fullGreeting = '';
      await for (final chunk in _aiService.sendMessageStream(
        messages: greetingMessages,
        systemPrompt: systemPrompt,
      )) {
        if (_isDisposed) break;

        // 更新消息内容
        currentStreamMessage.value += chunk;
        _updateAssistantMessage(currentStreamMessage.value);
        fullGreeting += chunk;
      }

      // 完整问候语生成完毕后，一次性播放
      if (!_isDisposed && _ttsService.isEnabled.value && fullGreeting.isNotEmpty) {
        await _ttsService.speak(fullGreeting);
      }
    } catch (e) {
      print('生成问候语失败: $e');
      // 移除未完成的消息
      if (_currentAssistantMessage != null) {
        messages.remove(_currentAssistantMessage);
      }
    } finally {
      if (!_isDisposed) {
        _currentAssistantMessage = null;
        currentStreamMessage.value = '';
      }
    }
  }

  // 开始语音输入
  void startVoiceInput() {
    isVoiceInputVisible.value = true;
    isVoiceConnecting.value = true;
    isRecording.value = false;
    recordingText.value = '';
    
    // 创建语音输入控制器
    Get.put(VoiceInputController(
      onRecordingResult: handleVoiceResult,
      onClosePanel: stopVoiceInput,
      onRecognizing: handleRecognizing,
    ));
  }

  void startRecording() {
    if (!isVoiceConnecting.value && isVoiceInputVisible.value) {
      isRecording.value = true;
    }
  }

  void stopRecording() {
    if (isRecording.value) {
      isRecording.value = false;
    }
  }

  void toggleMute() {
    isVoiceMuted.value = !isVoiceMuted.value;
  }

  void stopVoiceInput() {
    isVoiceInputVisible.value = false;
    isVoiceConnecting.value = true;
    isRecording.value = false;
    recordingText.value = '';
    
    // 如果存在临时语音消息但没有实际内容，则移除它
    if (_currentVoiceMessage != null && _currentVoiceMessage!.content == '🎤 ...') {
      messages.remove(_currentVoiceMessage);
    }
    _currentVoiceMessage = null;

    // 删除语音输入控制器
    try {
      if (Get.isRegistered<VoiceInputController>()) {
        Get.delete<VoiceInputController>();
      }
    } catch (e) {
      debugPrint('Error deleting VoiceInputController: $e');
    }
  }

  void handleRecognizing(String text) {
    if (text.isNotEmpty) {
      // 如果还没有创建临时消息，创建一个
      if (_currentVoiceMessage == null) {
        _currentVoiceMessage = Message(
          role: 'user',
          content: '🎤 $text',
          timestamp: DateTime.now(),
        );
        messages.add(_currentVoiceMessage!);
      } else {
        // 更新已存在的临时消息
        final index = messages.indexOf(_currentVoiceMessage!);
        if (index != -1) {
          messages[index] = Message(
            role: 'user',
            content: '🎤 $text',
            timestamp: _currentVoiceMessage!.timestamp,
          );
        }
      }
      _scrollToBottom();
    }
  }

  void handleVoiceResult(String text) {
    if (text.isNotEmpty) {
      if (_currentVoiceMessage != null) {
        final index = messages.indexOf(_currentVoiceMessage!);
        if (index != -1) {
          messages[index] = Message(
            role: 'user',
            content: text,
            timestamp: _currentVoiceMessage!.timestamp,
          );
        }
      }
      
      // 发送消息
      messageController.text = text;
      sendMessage();
      messageController.clear();
      
      _scrollToBottom();
    }
    // 不再在这里停止语音输入，让用户可以继续说下一句
    _currentVoiceMessage = null;
  }
}