import 'package:flutter/material.dart';
import 'dart:async';
import 'dart:typed_data';
import 'dart:convert';

import 'package:flutter/services.dart';
import 'package:arc/arc.dart';
import 'package:camera/camera.dart';
import 'package:shared_preferences/shared_preferences.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: HomePage(),
      debugShowCheckedModeBanner: false,
    );
  }
}

class HomePage extends StatefulWidget {
  const HomePage({super.key});

  @override
  State<HomePage> createState() => _HomePageState();
}

class _HomePageState extends State<HomePage> {
  String _platformVersion = 'Unknown';
  String _activeResult = '未激活';
  String _initResult = '未初始化';
  bool _isActivated = false;
  bool _isInitialized = false;

  final _arcPlugin = Arc();

  /// 虹软 SDK 配置信息（请替换为您自己的 AppId、SdkKey 和 ActiveKey）
  final String _appId = '4nPFuS2TYAQh9werHL2qbKjtTH9nnoixk7G6yqSUyjVH';
  final String _sdkKey = 'aWMTT3coxNQFETg9f3BGHCiBznAApXmcHFF3J5yQbsZ';
  final String _activeKey = 'NEAT7AU4KLCEK682';

  @override
  void initState() {
    super.initState();
    initPlatformState();
  }

  /// 获取平台版本
  Future<void> initPlatformState() async {
    String platformVersion;
    try {
      platformVersion =
          await _arcPlugin.getPlatformVersion() ?? 'Unknown platform version';
    } on PlatformException {
      platformVersion = 'Failed to get platform version.';
    }

    if (!mounted) return;

    setState(() {
      _platformVersion = platformVersion;
    });
  }

  /// 激活 SDK
  Future<void> _activeSDK() async {
    setState(() {
      _activeResult = '正在激活...';
    });

    try {
      final result = await _arcPlugin.activeOnline(
        appId: _appId,
        sdkKey: _sdkKey,
        activeKey: _activeKey,
      );

      if (result != null) {
        final success = result['success'] as bool? ?? false;
        final errorCode = result['errorCode'] as int? ?? -1;
        final message = result['message'] as String? ?? '未知错误';

        setState(() {
          _isActivated = success;
          _activeResult = success
              ? '激活成功！\n错误码: $errorCode\n$message'
              : '激活失败！\n错误码: $errorCode\n$message';
        });
      }
    } on PlatformException catch (e) {
      setState(() {
        _activeResult = '激活异常: ${e.message}';
      });
    }
  }

  /// 初始化引擎
  Future<void> _initEngine() async {
    if (!_isActivated) {
      setState(() {
        _initResult = '请先激活 SDK';
      });
      return;
    }

    setState(() {
      _initResult = '正在初始化...';
    });

    try {
      // 功能掩码组合：
      // ASF_FACE_DETECT = 0x00000001 (人脸检测)
      // ASF_FACE_RECOGNITION = 0x00000004 (人脸识别)
      // ASF_AGE = 0x00000008 (年龄检测)
      // ASF_GENDER = 0x00000010 (性别检测)
      // ASF_LIVENESS = 0x00000080 (RGB 活体检测)
      // 组合掩码 = 0x01 | 0x04 | 0x08 | 0x10 | 0x80 = 0x9D

      final result = await _arcPlugin.init(
        detectMode: 0, // 0=VIDEO 模式, 1=IMAGE 模式
        orient: 0, // 检测角度优先级
        maxFaceNum: 1, // 单人脸识别场景
        combinedMask: 0x9D, // 功能组合掩码
      );

      if (result != null) {
        final success = result['success'] as bool? ?? false;
        final errorCode = result['errorCode'] as int? ?? -1;
        final message = result['message'] as String? ?? '未知错误';

        setState(() {
          _isInitialized = success;
          _initResult = success
              ? '初始化成功！\n错误码: $errorCode\n$message'
              : '初始化失败！\n错误码: $errorCode\n$message';
        });
      }
    } on PlatformException catch (e) {
      setState(() {
        _initResult = '初始化异常: ${e.message}';
      });
    }
  }

  /// 跳转到人脸识别页面
  void _navigateToFaceRecognition() async {
    try {
      final cameras = await availableCameras();
      if (!mounted) return;

      Navigator.push(
        context,
        MaterialPageRoute(
          builder: (context) => FaceRecognitionScreen(
            arcPlugin: _arcPlugin,
            cameras: cameras,
          ),
        ),
      );
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('无法打开摄像头: $e')),
        );
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('虹软人脸识别 SDK 示例'),
        backgroundColor: Colors.blue,
        foregroundColor: Colors.white,
      ),
      body: SingleChildScrollView(
        padding: const EdgeInsets.all(16.0),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            // 平台信息
            Card(
              child: Padding(
                padding: const EdgeInsets.all(12.0),
                child: Text(
                  '运行平台: $_platformVersion',
                  style: const TextStyle(fontSize: 14),
                ),
              ),
            ),
            const SizedBox(height: 16),

            // 激活 SDK 按钮
            ElevatedButton(
              onPressed: _isActivated ? null : _activeSDK,
              style: ElevatedButton.styleFrom(
                backgroundColor: _isActivated ? Colors.grey : Colors.blue,
                foregroundColor: Colors.white,
                padding: const EdgeInsets.symmetric(vertical: 12),
              ),
              child: Text(
                _isActivated ? '已激活' : '激活 SDK',
                style: const TextStyle(fontSize: 16),
              ),
            ),
            const SizedBox(height: 8),
            Card(
              color: _isActivated ? Colors.green[50] : Colors.red[50],
              child: Padding(
                padding: const EdgeInsets.all(12.0),
                child: Text(
                  _activeResult,
                  style: TextStyle(
                    fontSize: 13,
                    color: _isActivated ? Colors.green[800] : Colors.red[800],
                  ),
                ),
              ),
            ),
            const SizedBox(height: 24),

            // 初始化引擎按钮
            ElevatedButton(
              onPressed: _isInitialized ? null : _initEngine,
              style: ElevatedButton.styleFrom(
                backgroundColor: _isInitialized ? Colors.grey : Colors.green,
                foregroundColor: Colors.white,
                padding: const EdgeInsets.symmetric(vertical: 12),
              ),
              child: Text(
                _isInitialized ? '已初始化' : '初始化引擎',
                style: const TextStyle(fontSize: 16),
              ),
            ),
            const SizedBox(height: 8),
            Card(
              color: _isInitialized ? Colors.green[50] : Colors.red[50],
              child: Padding(
                padding: const EdgeInsets.all(12.0),
                child: Text(
                  _initResult,
                  style: TextStyle(
                    fontSize: 13,
                    color: _isInitialized ? Colors.green[800] : Colors.red[800],
                  ),
                ),
              ),
            ),
            const SizedBox(height: 24),

            // 人脸识别按钮
            ElevatedButton(
              onPressed: _isInitialized ? _navigateToFaceRecognition : null,
              style: ElevatedButton.styleFrom(
                backgroundColor: _isInitialized ? Colors.purple : Colors.grey,
                foregroundColor: Colors.white,
                padding: const EdgeInsets.symmetric(vertical: 12),
              ),
              child: const Text(
                '开始人脸识别',
                style: TextStyle(fontSize: 16),
              ),
            ),
            const SizedBox(height: 24),

            // 使用说明
            const Card(
              child: Padding(
                padding: EdgeInsets.all(12.0),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(
                      '使用说明:',
                      style: TextStyle(
                        fontSize: 14,
                        fontWeight: FontWeight.bold,
                      ),
                    ),
                    SizedBox(height: 8),
                    Text(
                      '1. 点击"激活 SDK"按钮进行在线激活\n'
                      '2. 激活成功后点击"初始化引擎"按钮\n'
                      '3. 点击"开始人脸识别"进行注册/验证\n\n'
                      '注册流程: 人脸检测 → 活体检测 → 特征提取 → 存储\n'
                      '验证流程: 人脸检测 → 活体检测 → 特征提取 → 比对',
                      style: TextStyle(fontSize: 12),
                    ),
                  ],
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

/// 人脸识别页面 - 实现完整的注册和验证流程
class FaceRecognitionScreen extends StatefulWidget {
  final Arc arcPlugin;
  final List<CameraDescription> cameras;

  const FaceRecognitionScreen({
    super.key,
    required this.arcPlugin,
    required this.cameras,
  });

  @override
  State<FaceRecognitionScreen> createState() => _FaceRecognitionScreenState();
}

class _FaceRecognitionScreenState extends State<FaceRecognitionScreen> {
  CameraController? _cameraController;
  bool _isProcessing = false;
  String _statusMessage = '正在初始化摄像头...';

  // 检测结果
  int _faceCount = 0;
  int _rgbLivenessResult = -1; // -1=未检测, 0=非真人, 1=真人

  // 注册的人脸特征数据存储 key
  static const String _storedFeatureKey = 'stored_face_feature';

  // 当前帧的人脸信息
  Map<String, dynamic>? _currentFaceInfo;
  Uint8List? _currentNv21Data;
  int _currentWidth = 0;
  int _currentHeight = 0;

  // 模式: 0=注册, 1=验证
  int _mode = 0;
  String _modeLabel = '注册模式';

  // 验证结果
  double _similarity = 0.0;
  bool _verified = false;

  @override
  void initState() {
    super.initState();
    _initCamera();
  }

  /// 初始化摄像头
  Future<void> _initCamera() async {
    if (widget.cameras.isEmpty) {
      setState(() {
        _statusMessage = '没有可用的摄像头';
      });
      return;
    }

    // 选择前置摄像头
    CameraDescription? selectedCamera;
    for (var camera in widget.cameras) {
      if (camera.lensDirection == CameraLensDirection.front) {
        selectedCamera = camera;
        break;
      }
    }
    selectedCamera ??= widget.cameras.first;

    _cameraController = CameraController(
      selectedCamera,
      ResolutionPreset.medium,
      enableAudio: false,
      imageFormatGroup: ImageFormatGroup.nv21,
    );

    try {
      await _cameraController!.initialize();
      if (mounted) {
        setState(() {
          _statusMessage = '摄像头就绪';
        });
        _startImageStream();
      }
    } catch (e) {
      if (mounted) {
        setState(() {
          _statusMessage = '摄像头初始化失败: $e';
        });
      }
    }
  }

  /// 启动图像流
  void _startImageStream() {
    _cameraController?.startImageStream(_onImageAvailable);
  }

  /// 图像帧回调 - 人脸检测
  void _onImageAvailable(CameraImage image) async {
    if (_isProcessing) return;
    _isProcessing = true;

    try {
      final int width = image.width;
      final int height = image.height;
      final nv21Data = _extractNV21(image, width, height);

      // 保存当前帧数据用于后续特征提取
      _currentNv21Data = nv21Data;
      _currentWidth = width;
      _currentHeight = height;

      // 人脸检测 + RGB 活体检测
      final detectResult = await widget.arcPlugin.detectFaces(
        data: nv21Data,
        width: width,
        height: height,
        format: 2050,
      );

      if (detectResult != null) {
        final success = detectResult['success'] == true;
        final faceList = detectResult['faceList'] as List? ?? [];
        final rgbLiveness = detectResult['rgbLiveness'] as int? ?? -1;

        if (success && faceList.isNotEmpty) {
          // 保存第一张人脸信息
          _currentFaceInfo = Map<String, dynamic>.from(faceList[0] as Map);

          if (mounted) {
            setState(() {
              _faceCount = faceList.length;
              _rgbLivenessResult = rgbLiveness;
              _statusMessage = _rgbLivenessResult == 1 ? '检测到真人' : '检测中...';
            });
          }
        } else {
          _currentFaceInfo = null;
          if (mounted) {
            setState(() {
              _faceCount = 0;
              _rgbLivenessResult = -1;
              _statusMessage = '未检测到人脸';
            });
          }
        }
      }
    } catch (e) {
      debugPrint('人脸检测异常: $e');
    } finally {
      _isProcessing = false;
    }
  }

  /// 提取 NV21 数据
  Uint8List _extractNV21(CameraImage image, int width, int height) {
    final ySize = width * height;
    final nv21Size = ySize * 3 ~/ 2;

    if (image.planes.length == 1) {
      final plane = image.planes[0];
      final bytesPerRow = plane.bytesPerRow;

      if (bytesPerRow == width) {
        return plane.bytes;
      }

      final nv21 = Uint8List(nv21Size);

      for (int row = 0; row < height; row++) {
        final srcOffset = row * bytesPerRow;
        final dstOffset = row * width;
        nv21.setRange(dstOffset, dstOffset + width, plane.bytes, srcOffset);
      }

      final uvHeight = height ~/ 2;
      for (int row = 0; row < uvHeight; row++) {
        final srcOffset = (height + row) * bytesPerRow;
        final dstOffset = ySize + row * width;
        nv21.setRange(dstOffset, dstOffset + width, plane.bytes, srcOffset);
      }

      return nv21;
    }

    final yPlane = image.planes[0];
    final yStride = yPlane.bytesPerRow;

    final nv21 = Uint8List(nv21Size);

    for (int row = 0; row < height; row++) {
      final srcOffset = row * yStride;
      final dstOffset = row * width;
      nv21.setRange(dstOffset, dstOffset + width, yPlane.bytes, srcOffset);
    }

    if (image.planes.length >= 2) {
      final uvPlane = image.planes[1];
      final uvStride = uvPlane.bytesPerRow;
      final uvHeight = height ~/ 2;

      for (int row = 0; row < uvHeight; row++) {
        final srcOffset = row * uvStride;
        final dstOffset = ySize + row * width;
        nv21.setRange(dstOffset, dstOffset + width, uvPlane.bytes, srcOffset);
      }
    }

    return nv21;
  }

  /// 注册人脸
  Future<void> _registerFace() async {
    if (_currentFaceInfo == null || _currentNv21Data == null) {
      _showMessage('未检测到人脸');
      return;
    }

    if (_rgbLivenessResult != 1) {
      _showMessage('请确保是真人');
      return;
    }

    setState(() {
      _statusMessage = '正在提取特征...';
    });

    try {
      // 提取特征 (REGISTER 模式)
      final result = await widget.arcPlugin.extractFaceFeature(
        data: _currentNv21Data!,
        width: _currentWidth,
        height: _currentHeight,
        rectLeft: _currentFaceInfo!['rectLeft'] as int,
        rectTop: _currentFaceInfo!['rectTop'] as int,
        rectRight: _currentFaceInfo!['rectRight'] as int,
        rectBottom: _currentFaceInfo!['rectBottom'] as int,
        faceOrientation: _currentFaceInfo!['orient'] as int? ?? 0,
        faceId: _currentFaceInfo!['faceId'] as int? ?? -1,
        extractType: 0, // REGISTER 模式
        mask: 0,
      );

      if (result != null && result['success'] == true) {
        final featureData = result['featureData'] as Uint8List;

        // 存储特征数据到本地
        final prefs = await SharedPreferences.getInstance();
        await prefs.setString(_storedFeatureKey, _bytesToBase64(featureData));

        setState(() {
          _statusMessage = '注册成功！特征已保存';
        });
        _showMessage('人脸注册成功！');
      } else {
        final errorMsg = result?['message'] ?? '未知错误';
        setState(() {
          _statusMessage = '特征提取失败: $errorMsg';
        });
      }
    } catch (e) {
      setState(() {
        _statusMessage = '注册异常: $e';
      });
    }
  }

  /// 验证人脸
  Future<void> _verifyFace() async {
    if (_currentFaceInfo == null || _currentNv21Data == null) {
      _showMessage('未检测到人脸');
      return;
    }

    if (_rgbLivenessResult != 1) {
      _showMessage('请确保是真人');
      return;
    }

    // 读取存储的特征
    final prefs = await SharedPreferences.getInstance();
    final storedFeatureBase64 = prefs.getString(_storedFeatureKey);

    if (storedFeatureBase64 == null) {
      _showMessage('请先注册人脸');
      return;
    }

    setState(() {
      _statusMessage = '正在提取特征...';
    });

    try {
      // 提取当前帧特征 (RECOGNIZE 模式)
      final result = await widget.arcPlugin.extractFaceFeature(
        data: _currentNv21Data!,
        width: _currentWidth,
        height: _currentHeight,
        rectLeft: _currentFaceInfo!['rectLeft'] as int,
        rectTop: _currentFaceInfo!['rectTop'] as int,
        rectRight: _currentFaceInfo!['rectRight'] as int,
        rectBottom: _currentFaceInfo!['rectBottom'] as int,
        faceOrientation: _currentFaceInfo!['orient'] as int? ?? 0,
        faceId: _currentFaceInfo!['faceId'] as int? ?? -1,
        extractType: 1, // RECOGNIZE 模式
        mask: 0,
      );

      if (result != null && result['success'] == true) {
        final currentFeature = result['featureData'] as Uint8List;
        final storedFeature = _base64ToBytes(storedFeatureBase64);

        // 比对特征
        final compareResult = await widget.arcPlugin.compareFaceFeature(
          featureData1: currentFeature,
          featureData2: storedFeature,
          compareModel: 0, // LIFE_PHOTO 模式
        );

        if (compareResult != null && compareResult['success'] == true) {
          final similarity = compareResult['similarity'] as double? ?? 0.0;
          final threshold = 0.8; // 推荐阈值
          final isMatch = similarity >= threshold;

          setState(() {
            _similarity = similarity;
            _verified = isMatch;
            _statusMessage = isMatch
                ? '验证通过！相似度: ${(similarity * 100).toStringAsFixed(1)}%'
                : '验证失败！相似度: ${(similarity * 100).toStringAsFixed(1)}%';
          });
        } else {
          setState(() {
            _statusMessage = '比对失败';
          });
        }
      } else {
        setState(() {
          _statusMessage = '特征提取失败';
        });
      }
    } catch (e) {
      setState(() {
        _statusMessage = '验证异常: $e';
      });
    }
  }

  /// 切换模式
  void _toggleMode() {
    setState(() {
      _mode = _mode == 0 ? 1 : 0;
      _modeLabel = _mode == 0 ? '注册模式' : '验证模式';
      _similarity = 0.0;
      _verified = false;
    });
  }

  /// 清除注册数据
  Future<void> _clearRegistration() async {
    final prefs = await SharedPreferences.getInstance();
    await prefs.remove(_storedFeatureKey);
    setState(() {
      _similarity = 0.0;
      _verified = false;
      _statusMessage = '已清除注册数据';
    });
    _showMessage('注册数据已清除');
  }

  /// 字节数组转 Base64
  String _bytesToBase64(Uint8List bytes) {
    return base64Encode(bytes);
  }

  /// Base64 转字节数组
  Uint8List _base64ToBytes(String base64) {
    return base64Decode(base64);
  }

  /// 显示消息
  void _showMessage(String message) {
    if (mounted) {
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text(message)),
      );
    }
  }

  @override
  void dispose() {
    _cameraController?.stopImageStream();
    _cameraController?.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(_modeLabel),
        backgroundColor: Colors.purple,
        foregroundColor: Colors.white,
        actions: [
          IconButton(
            icon: const Icon(Icons.swap_horiz),
            onPressed: _toggleMode,
            tooltip: '切换模式',
          ),
          IconButton(
            icon: const Icon(Icons.delete_outline),
            onPressed: _clearRegistration,
            tooltip: '清除注册数据',
          ),
        ],
      ),
      body: Column(
        children: [
          // 摄像头预览
          Expanded(
            child: _cameraController != null &&
                    _cameraController!.value.isInitialized
                ? Center(
                    child: CameraPreview(_cameraController!),
                  )
                : Center(
                    child: Column(
                      mainAxisAlignment: MainAxisAlignment.center,
                      children: [
                        const CircularProgressIndicator(),
                        const SizedBox(height: 16),
                        Text(_statusMessage),
                      ],
                    ),
                  ),
          ),

          // 检测信息和操作面板
          Container(
            width: double.infinity,
            padding: const EdgeInsets.all(16),
            color: Colors.black87,
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                // 状态信息
                Text(
                  _statusMessage,
                  style: const TextStyle(
                    color: Colors.white,
                    fontSize: 16,
                    fontWeight: FontWeight.bold,
                  ),
                ),
                const SizedBox(height: 8),

                // 人脸和活体状态
                Row(
                  children: [
                    Icon(
                      _faceCount > 0 ? Icons.face : Icons.face_retouching_off,
                      color: _faceCount > 0 ? Colors.green : Colors.grey,
                      size: 20,
                    ),
                    const SizedBox(width: 8),
                    Text(
                      '人脸: ${_faceCount > 0 ? "已检测" : "未检测"}',
                      style: TextStyle(
                        color: _faceCount > 0 ? Colors.green : Colors.grey,
                        fontSize: 14,
                      ),
                    ),
                    const SizedBox(width: 16),
                    Icon(
                      _rgbLivenessResult == 1
                          ? Icons.check_circle
                          : _rgbLivenessResult == 0
                              ? Icons.cancel
                              : Icons.help_outline,
                      color: _rgbLivenessResult == 1
                          ? Colors.green
                          : _rgbLivenessResult == 0
                              ? Colors.red
                              : Colors.orange,
                      size: 20,
                    ),
                    const SizedBox(width: 8),
                    Text(
                      '活体: ${_rgbLivenessResult == 1 ? "真人" : _rgbLivenessResult == 0 ? "非真人" : "未知"}',
                      style: TextStyle(
                        color: _rgbLivenessResult == 1
                            ? Colors.green
                            : _rgbLivenessResult == 0
                                ? Colors.red
                                : Colors.orange,
                        fontSize: 14,
                      ),
                    ),
                  ],
                ),

                // 验证结果显示
                if (_mode == 1 && _similarity > 0) ...[
                  const SizedBox(height: 8),
                  const Divider(color: Colors.white24),
                  const SizedBox(height: 8),
                  Row(
                    children: [
                      Icon(
                        _verified ? Icons.verified_user : Icons.warning,
                        color: _verified ? Colors.green : Colors.red,
                        size: 24,
                      ),
                      const SizedBox(width: 8),
                      Text(
                        '相似度: ${(_similarity * 100).toStringAsFixed(1)}%',
                        style: TextStyle(
                          color: _verified ? Colors.green : Colors.red,
                          fontSize: 18,
                          fontWeight: FontWeight.bold,
                        ),
                      ),
                      const SizedBox(width: 8),
                      Text(
                        _verified ? '验证通过' : '非本人',
                        style: TextStyle(
                          color: _verified ? Colors.green : Colors.red,
                          fontSize: 14,
                        ),
                      ),
                    ],
                  ),
                ],

                const SizedBox(height: 12),

                // 操作按钮
                Row(
                  children: [
                    Expanded(
                      child: ElevatedButton.icon(
                        onPressed: _mode == 0 ? _registerFace : _verifyFace,
                        icon: Icon(_mode == 0 ? Icons.person_add : Icons.verified_user),
                        label: Text(_mode == 0 ? '注册人脸' : '验证身份'),
                        style: ElevatedButton.styleFrom(
                          backgroundColor: _mode == 0 ? Colors.blue : Colors.green,
                          foregroundColor: Colors.white,
                          padding: const EdgeInsets.symmetric(vertical: 12),
                        ),
                      ),
                    ),
                  ],
                ),

                // 提示
                const SizedBox(height: 8),
                Text(
                  _mode == 0
                      ? '提示: 注册时会提取人脸特征并保存到本地'
                      : '提示: 验证时会与已注册的特征进行比对，阈值 0.8',
                  style: const TextStyle(
                    color: Colors.white54,
                    fontSize: 11,
                  ),
                ),
              ],
            ),
          ),
        ],
      ),
    );
  }
}