import 'dart:async';
import 'dart:convert';
import 'package:camera/camera.dart';
import 'package:fis_jsonrpc/rpc.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:get/get.dart';
import 'package:google_mlkit_face_detection/google_mlkit_face_detection.dart';
import 'package:image_gallery_saver/image_gallery_saver.dart';
import 'package:vitalapp/architecture/storage/storage.dart';
import 'package:vitalapp/architecture/utils/prompt_box.dart';
import 'package:vitalapp/components/alert_dialog.dart';
import 'package:vitalapp/managers/interfaces/cache.dart';
import 'package:fis_common/logger/logger.dart';
import 'package:vitalapp/rpc.dart';
import 'package:vitalapp/store/store.dart';
import 'dart:ui' as ui;
import 'index.dart';
import 'package:fis_common/index.dart';

class FacialRecognitionController extends GetxController
    with WidgetsBindingObserver {
  FacialRecognitionController({
    required this.mode,
    this.patientInfo,
  });

  final FacialRecognitionMode mode;

  /// 当前需要录入的身份信息
  final PatientDTO? patientInfo;

  final state = FacialRecognitionState();

  List<CameraDescription> _cameras = <CameraDescription>[];
  List<CameraDescription> get cameras => _cameras;

  CameraController? kCameraController;
  double _minAvailableExposureOffset = 0.0;
  double _maxAvailableExposureOffset = 0.0;
  double _minAvailableZoom = 1.0;
  double _maxAvailableZoom = 1.0;
  final double _currentScale = 1.0;
  double _baseScale = 1.0;

  // 屏幕上手指数量
  int pointers = 0;

  // 当前需要返回的身份信息
  IdCardInfoModel idCardInfo = IdCardInfoModel();

  /// 开始缩放
  void handleScaleStart(ScaleStartDetails details) {
    _baseScale = _currentScale;
  }

  /// 当前捕获帧的人脸列表
  List<Face> kFrameFacesResult = [];

  /// 当前捕获帧大小
  Size kFrameImageSize = Size.zero;

  /// 缩放更新
  Future<void> handleScaleUpdate(ScaleUpdateDetails details) async {
    // When there are not exactly two fingers on screen don't scale
    if (kCameraController == null || pointers != 2) {
      return;
    }

    // 屏蔽缩放
    // _currentScale = (_baseScale * details.scale)
    //     .clamp(_minAvailableZoom, _maxAvailableZoom);

    // await kCameraController!.setZoomLevel(_currentScale);
  }

  /// 修改对焦点 [暂不执行]
  void onViewFinderTap(TapDownDetails details, BoxConstraints constraints) {
    if (kCameraController == null) {
      return;
    }

    final CameraController cameraController = kCameraController!;

    final Offset offset = Offset(
      details.localPosition.dx / constraints.maxWidth,
      details.localPosition.dy / constraints.maxHeight,
    );
    cameraController.setExposurePoint(offset);
    cameraController.setFocusPoint(offset);
  }

  /// 初始化相机
  Future<void> initAvailableCameras() async {
    try {
      _cameras = await availableCameras();
      if (_cameras.isNotEmpty) {
        // state.isCameraReady = true;
      }
      // print("cameras: ${_cameras.length}");
    } on CameraException catch (e) {
      logger.e("cameras: ${e.code} ${e.description}");
    }
  }

  /// 启动指定相机
  Future<void> openNewCamera(CameraDescription cameraDescription) async {
    final CameraController? oldController = kCameraController;
    if (oldController != null) {
      // `kCameraController` needs to be set to null before getting disposed,
      // to avoid a race condition when we use the kCameraController that is being
      // disposed. This happens when camera permission dialog shows up,
      // which triggers `didChangeAppLifecycleState`, which disposes and
      // re-creates the kCameraController.
      kCameraController = null;
      await oldController.dispose();
    }

    final CameraController cameraController = CameraController(
      cameraDescription,
      ResolutionPreset.max,
      enableAudio: false,
      imageFormatGroup: ImageFormatGroup.jpeg,
    );

    kCameraController = cameraController;

    // If the kCameraController is updated then update the UI.
    cameraController.addListener(() {
      if (cameraController.value.hasError) {
        PromptBox.toast(
            "Camera error ${cameraController.value.errorDescription}");
      }
    });

    try {
      await cameraController.initialize();
      await Future.wait(<Future<Object?>>[
        // The exposure mode is currently not supported on the web.
        ...!kIsWeb
            ? <Future<Object?>>[
                cameraController.getMinExposureOffset().then(
                    (double value) => _minAvailableExposureOffset = value),
                cameraController
                    .getMaxExposureOffset()
                    .then((double value) => _maxAvailableExposureOffset = value)
              ]
            : <Future<Object?>>[],
        cameraController
            .getMaxZoomLevel()
            .then((double value) => _maxAvailableZoom = value),
        cameraController
            .getMinZoomLevel()
            .then((double value) => _minAvailableZoom = value),
      ]);
    } on CameraException catch (e) {
      switch (e.code) {
        case 'CameraAccessDenied':
          PromptBox.toast('You have denied camera access.');
          break;
        case 'CameraAccessDeniedWithoutPrompt':
          // iOS only
          PromptBox.toast('Please go to Settings app to enable camera access.');
          break;
        case 'CameraAccessRestricted':
          // iOS only
          PromptBox.toast('Camera access is restricted.');
          break;
        case 'AudioAccessDenied':
          PromptBox.toast('You have denied audio access.');
          break;
        case 'AudioAccessDeniedWithoutPrompt':
          // iOS only
          PromptBox.toast('Please go to Settings app to enable audio access.');
          break;
        case 'AudioAccessRestricted':
          // iOS only
          PromptBox.toast('Audio access is restricted.');
          break;
        default:
          PromptBox.toast('Error: ${e.code}\n${e.description}');
          break;
      }
    }
  }

  /// 遍历当前相机列表并启动后置相机
  void openBackCamera() async {
    logger.i("openBackCamera 启动前置摄像头");
    if (_cameras.isEmpty) {
      PromptBox.toast('Error: No cameras found.');
    } else {
      for (CameraDescription cameraDescription in _cameras) {
        if (cameraDescription.lensDirection == CameraLensDirection.back) {
          await openNewCamera(cameraDescription);
          lockCaptureOrientation();
          state.isUsingFrontCamera = false;
          update();
          state.isCameraReady = true;
          break;
        }
      }
    }
  }

  /// 遍历当前相机列表并启动前置相机
  void openFrontCamera() async {
    logger.i("openFrontCamera 启动后置摄像头");
    if (_cameras.isEmpty) {
      PromptBox.toast('Error: No cameras found.');
    } else {
      for (CameraDescription cameraDescription in _cameras) {
        if (cameraDescription.lensDirection == CameraLensDirection.front) {
          await openNewCamera(cameraDescription);
          state.isUsingFrontCamera = true;
          lockCaptureOrientation();
          update();
          state.isCameraReady = true;
          break;
        }
      }
    }
  }

  /// 前后置摄像头切换

  void switchCameraLens() async {
    if (state.isUsingFrontCamera) {
      openBackCamera();
    } else {
      openFrontCamera();
    }
  }

  /// 相机锁定旋转
  Future<void> lockCaptureOrientation() async {
    final CameraController? cameraController = kCameraController;
    if (cameraController == null || !cameraController.value.isInitialized) {
      PromptBox.toast('Error: select a camera first.');
      return;
    }

    if (!cameraController.value.isCaptureOrientationLocked) {
      try {
        await cameraController
            .lockCaptureOrientation(DeviceOrientation.landscapeLeft);
      } on CameraException catch (e) {
        PromptBox.toast('Error: ${e.code}\n${e.description}');
      }
    } else {
      PromptBox.toast('Rotation lock is already enabled.');
    }
  }

  /// 执行一次拍摄
  Future<XFile?> takePicture() async {
    final CameraController? cameraController = kCameraController;
    if (cameraController == null || !cameraController.value.isInitialized) {
      PromptBox.toast('Error: select a camera first.');
      return null;
    }

    if (cameraController.value.isTakingPicture) {
      // A capture is already pending, do nothing.
      return null;
    }

    try {
      final XFile file = await cameraController.takePicture();
      return file;
    } on CameraException catch (e) {
      PromptBox.toast('Error: ${e.code}\n${e.description}');
      return null;
    }
  }

  /// 测试图像文件缓存，print 遍历输出
  void debugShowCache() async {
    final cacheManager = Get.find<ICacheManager>();
    double cacheSize = await cacheManager.getCacheSize();
    double imageCacheSize = await cacheManager.getImageCacheSize();
    debugPrint('cacheSize = $cacheSize : ${formatSize(cacheSize)}');
    debugPrint(
        'imageCacheSize = $imageCacheSize : ${formatSize(imageCacheSize)}');
  }

  /// 文件大小转为可读 Str
  static String formatSize(double value) {
    List<String> unitArr = ['B', 'K', 'M', 'G'];
    int index = 0;
    while (value > 1024) {
      index++;
      value = value / 1024;
    }
    String size = value.toStringAsFixed(2);
    return size + unitArr[index];
  }

  /// 保存到相册
  void saveImageToGallery(XFile image) async {
    // 获取图像的字节数据
    Uint8List bytes = await image.readAsBytes();

    // 将图像保存到相册
    await ImageGallerySaver.saveImage(bytes, quality: 100);
  }

  /// 处理图像裁切
  Future<String> clipLocalImage(XFile soureceImage, double scale) async {
    assert(scale >= 1, 'scale must be greater than 1');
    // 获取图像的字节数据
    Uint8List bytes = await soureceImage.readAsBytes();
    var codec = await ui.instantiateImageCodec(bytes);
    var nextFrame = await codec.getNextFrame();
    var image = nextFrame.image;
    Rect src = Rect.fromLTWH(
      (scale - 1) / 2 / scale * image.width.toDouble(),
      (scale - 1) / 2 / scale * image.height.toDouble(),
      image.width.toDouble() / scale,
      image.height.toDouble() / scale,
    );
    Rect dst =
        Rect.fromLTWH(0, 0, image.width.toDouble(), image.height.toDouble());
    ui.Image croppedImage = await getCroppedImage(image, src, dst);
    ByteData? newImageBytes =
        await croppedImage.toByteData(format: ui.ImageByteFormat.png);
    if (newImageBytes == null) {
      return '';
    }
    Uint8List newImageUint8List = newImageBytes.buffer.asUint8List();

    /// FIXME 不要存到相册而是存到临时目录
    Map<Object?, Object?> result =
        await ImageGallerySaver.saveImage(newImageUint8List, quality: 100);
    String jsonString = jsonEncode(result);
    Map<String, dynamic> json = jsonDecode(jsonString);
    String? filePath = json['filePath'];
    return filePath ?? '';
  }

  /// 获取图像文件的图像尺寸
  Future<Size> getImageSize(XFile soureceImage) async {
    // 获取图像的字节数据
    Uint8List bytes = await soureceImage.readAsBytes();
    var codec = await ui.instantiateImageCodec(bytes);
    var nextFrame = await codec.getNextFrame();
    var image = nextFrame.image;
    return Size(image.width.toDouble(), image.height.toDouble());
  }

  /// 获取裁切后的图像
  Future<ui.Image> getCroppedImage(ui.Image image, Rect src, Rect dst) {
    var pictureRecorder = ui.PictureRecorder();
    Canvas canvas = Canvas(pictureRecorder);
    canvas.drawImageRect(image, src, dst, Paint());
    return pictureRecorder.endRecording().toImage(
          dst.width.floor(),
          dst.height.floor(),
        );
  }

  /// 发生开始人脸识别/人像采集事件
  void onCaptureFaceButtonPressed() {
    if (mode == FacialRecognitionMode.faceRecognition) {
      doFacialRecognitionTimes = 0;
      state.isRunningFaceRecognition = true;
      doFacialRecognition(); // 人脸识别
    } else {
      doFaceInput(); // 人像采集
    }
  }

  /// 人脸识别执行次数
  int doFacialRecognitionTimes = 0;

  /// 人脸识别逻辑
  void doFacialRecognition() async {
    logger.i("doFacialRecognition 进行人脸识别 $doFacialRecognitionTimes");
    doFacialRecognitionTimes++;
    if (doFacialRecognitionTimes >= 10) {
      // 尝试十次后宣告失败
      state.isRunningFaceRecognition = false;
      PromptBox.toast('人脸识别失败，请先录入人脸信息或更新人脸信息');
      return;
    }
    if (kCameraController == null) {
      state.isRunningFaceRecognition = false;
      return;
    }
    final XFile? file = await takePicture();
    state.processingImageLocalPath = '';
    if (file != null) {
      faceDetector = FaceDetector(options: FaceDetectorOptions());
      // faceDetector =
      //     FaceDetector(options: FaceDetectorOptions(enableContours: true));
      int faceNum =
          await doDetection(faceDetector, file.path); // max 分辨率下检测用时大约 100ms

      if (doFacialRecognitionTimes >= 10) {
        // 手动取消，中途跳出循环
        state.isRunningFaceRecognition = false;
        return;
      }

      if (faceNum == 0) {
        PromptBox.toast('请将面部保持在识别框内');
        await Future.delayed(const Duration(seconds: 2));
      } else if (faceNum > 1) {
        PromptBox.toast('请保持只有一张面部在识别范围内');
        await Future.delayed(const Duration(seconds: 2));
      } else {
        final String fileType = file.path.split('.').last;
        if (!['png', 'jpg'].contains(fileType)) {
          PromptBox.toast('上传的图像类型错误');
          return;
        }
        state.processingImageLocalPath = file.path;
        final url = await rpc.storage.upload(
          file,
          fileType: fileType,
        );
        print('⭐⭐⭐⭐⭐⭐⭐⭐ url: $url');
        try {
          if (url == null || url.isEmpty) {
            PromptBox.toast('上传失败');
            throw Exception('图像上传超时');
          }
          PatientBaseDTO result =
              await rpc.patient.getPatientBaseByFaceImageAsync(
            GetPatientBaseByFaceImageRequest(
              token: Store.user.token,
              image: url,
            ),
          );
          state.processingImageLocalPath = '';
          if (doFacialRecognitionTimes >= 10) {
            // 手动取消，中途跳出循环
            state.isRunningFaceRecognition = false;
            return;
          }
          if (result.faceScanErrorType == FaceScanErrorTypeEnum.Success) {
            finishFaceDetection(result);
            // 识别成功，阻断循环
            doFacialRecognitionTimes = 10;
          } else if (result.faceScanErrorType ==
              FaceScanErrorTypeEnum.NoCreated) {
            PromptBox.toast('识别到未采集过的人脸信息');

            /// 如果返回结果告知不在档，则快进到失败十次提示重新建档
            doFacialRecognitionTimes = 10;
          } else {
            if (result.errorMessage.isNotNullOrEmpty) {
              logger.e(result.errorMessage!);
            }
            if (kDebugMode) {
              PromptBox.toast('无法识别面部信息，请确保面部清晰可见: $doFacialRecognitionTimes');
            } else {
              PromptBox.toast('无法识别面部信息，请确保面部清晰可见');
            }
            await Future.delayed(const Duration(seconds: 1));
          }
        } catch (e) {
          logger.e("getPatientBaseByFaceImageAsync failed: $e", e);
          state.processingImageLocalPath = '';
        }
        state.processingImageLocalPath = '';
      }
    }

    if (doFacialRecognitionTimes >= 10) {
      // 手动取消，中途跳出循环
      state.isRunningFaceRecognition = false;
      return;
    }
    doFacialRecognition();
  }

  /// 人像采集逻辑
  void doFaceInput() async {
    if (kCameraController == null) {
      return;
    }
    if (patientInfo != null) {
      idCardInfo.idCardNumber = patientInfo!.cardNo!;
    }
    final XFile? file = await takePicture();
    state.processingImageLocalPath = '';
    if (file != null) {
      faceDetector = FaceDetector(options: FaceDetectorOptions());
      // faceDetector =
      //     FaceDetector(options: FaceDetectorOptions(enableContours: true));
      int faceNum =
          await doDetection(faceDetector, file.path); // max 分辨率下检测用时大约 100ms

      if (faceNum == 0) {
        PromptBox.toast('请将面部保持在识别框内');
        return;
      } else if (faceNum > 1) {
        PromptBox.toast('请保持只有一张面部在识别范围内');
        return;
      }

      final String fileType = file.path.split('.').last;
      if (!['png', 'jpg'].contains(fileType)) {
        PromptBox.toast('上传的图像类型错误');
        return;
      }
      state.processingImageLocalPath = file.path;
      final url = await rpc.storage.upload(
        file,
        fileType: fileType,
      );
      print('⭐⭐⭐⭐⭐⭐⭐⭐ url: $url');
      try {
        if (url == null || url.isEmpty) {
          PromptBox.toast('上传失败');
          throw Exception('图像上传超时');
        }
        SavePersonDTO result =
            await rpc.patient.savePatientBaseByFaceImageAsync(
          SavePatientBaseByFaceImageRequest(
            cardNo: idCardInfo.idCardNumber,
            token: Store.user.token,
            image: url,
          ),
        );
        state.processingImageLocalPath = '';
        if (result.success) {
          Get.back(result: true);
        } else {
          // 如果失败且存在 bindCardNo ，则说明已录入过
          if (result.bindCardNo != null) {
            if (result.bindCardNo == idCardInfo.idCardNumber) {
              Get.back(result: true);
            } else {
              /// 询问是否需要解绑原身份证并绑定当前身份证
              /// 原身份证：result.bindCardNo
              /// 当前身份证：idCardInfo.idCardNumber
              bool? dialogResult = await Get.dialog<bool>(
                VAlertDialog(
                  title: '提示',
                  width: 600,
                  content: Container(
                    margin:
                        const EdgeInsets.only(bottom: 20, left: 20, right: 20),
                    child: Text(
                      '该人脸已绑定身份证（${result.bindCardNo}）\n是否解绑并绑定当前身份证（${idCardInfo.idCardNumber}）？',
                      style: const TextStyle(fontSize: 20),
                      textAlign: TextAlign.left,
                    ),
                  ),
                  showCancel: true,
                  onConfirm: () async {
                    bool success = await unbindAndCreateByFaceImageAsync(
                      result.bindCardNo!,
                      idCardInfo.idCardNumber,
                      url,
                    );
                    if (success) {
                      Get.back(result: true);
                    } else {
                      Get.back(result: false);
                    }
                  },
                ),
              );
              if (dialogResult != null && dialogResult) {
                Get.back(result: true);
              } else if (dialogResult != null && !dialogResult) {
                PromptBox.toast('人脸数据存入失败');
              } else {
                PromptBox.toast('人脸数据存入取消');
              }
            }
          } else {
            PromptBox.toast('人脸数据存入失败: ${result.errMessage}');
          }
        }
      } catch (e) {
        state.processingImageLocalPath = '';
        logger.e("savePatientBaseByFaceImageAsync failed: $e", e);
      }
      state.processingImageLocalPath = '';
    }
  }

  /// 取消采集
  void doCancelCapture() {
    doFacialRecognitionTimes = 10;
    state.isRunningFaceRecognition = false;
  }

  /// 重新绑定并创建新档案
  Future<bool> unbindAndCreateByFaceImageAsync(
      String oldId, String newId, String url) async {
    DeletePersonDTO result = await rpc.patient.unbindAndCreateByFaceImageAsync(
      UnbindAndCreateByFaceImageRequest(
        oldCardNo: oldId,
        newCardNo: newId,
        token: Store.user.token,
        image: url,
      ),
    );
    return result.success;
  }

  /// 在 widget 内存中分配后立即调用。
  @override
  void onInit() async {
    // await initCamera();
    super.onInit();
    WidgetsBinding.instance.addObserver(this);
  }

  /// 在 onInit() 之后调用 1 帧。这是进入的理想场所
  @override
  void onReady() async {
    super.onReady();
    logger.i(
        "onReady 进入人脸识别/采集页面，当前模式：${mode == FacialRecognitionMode.faceRecognition ? '人脸识别' : '人像采集'}");
    await initAvailableCameras();
    if (state.isUsingFrontCamera) {
      openFrontCamera();
    } else {
      openBackCamera();
    }
  }

  /// 在 [onDelete] 方法之前调用。
  @override
  void onClose() {
    logger.i("onClose 离开人脸识别/采集页面");
    super.onClose();
    // 关闭人脸采集
    doCancelCapture();
    final cacheManager = Get.find<ICacheManager>();
    cacheManager.clearApplicationImageCache();
    closeDetector();
    WidgetsBinding.instance.removeObserver(this);
    final CameraController? cameraController = kCameraController;
    if (cameraController != null) {
      kCameraController = null;
      cameraController.dispose();
    }
  }

  /// dispose 释放内存
  @override
  void dispose() {
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) async {
    super.didChangeAppLifecycleState(state);
    final CameraController? cameraController = kCameraController;

    // App state changed before we got the chance to initialize.
    if (cameraController == null || !cameraController.value.isInitialized) {
      return;
    }

    if (state == AppLifecycleState.inactive) {
      cameraController.dispose();
      this.state.isCameraReady = false;
    } else if (state == AppLifecycleState.resumed) {
      await openNewCamera(cameraController.description);
      this.state.isCameraReady = true;
    }
  }

  /// 完成人脸识别
  void finishFaceDetection(PatientBaseDTO patient) {
    Get.back<FaceRecognitionResult>(
      result: FaceRecognitionResult(
        success: true,
        patientInfo: patient,
      ),
    );
  }

  /// 面部识别 基于 Google's ML Kit
  InputImage inputImage = InputImage.fromFilePath('');
  FaceDetector faceDetector = FaceDetector(options: FaceDetectorOptions());

  // 进行一次人脸检测 (返回人脸数量)
  Future<int> doDetection(
    FaceDetector faceDetector,
    String imagePath,
  ) async {
    inputImage = InputImage.fromFilePath(imagePath);
    // inputImage = image;
    final List<Face> faces = await faceDetector.processImage(inputImage);
    kFrameFacesResult = [];
    kFrameFacesResult.addAll(faces);
    return kFrameFacesResult.length;
  }

  /// 销毁检测器
  void closeDetector() {
    faceDetector.close();
  }
}

class FaceRecognitionResult {
  bool success;

  /// 身份信息
  PatientBaseDTO patientInfo;

  FaceRecognitionResult({
    required this.success,
    required this.patientInfo,
  });
}

/// 运行模式
enum FacialRecognitionMode {
  /// 人脸识别（用于登录）
  faceRecognition,

  /// 人像采集
  faceInput,
}