import 'dart:io';
import 'package:image_picker/image_picker.dart';
import 'package:sino_med_cloud/core/utils/logger.dart';
import 'package:sino_med_cloud/core/utils/toast_utils.dart';
import 'package:sino_med_cloud/permission/permission_service.dart';
import 'media_exception.dart';

/// 相册和快速拍照服务
/// 
/// 适合普通拍照、表单上传、医疗资料拍照（非实时）
/// 
/// 使用示例：
/// ```dart
/// // 从相册选择
/// final file = await PickerService.pickFromGallery();
/// 
/// // 使用系统相机拍照
/// final photo = await PickerService.pickFromCamera();
/// ```
class PickerService {
  static final ImagePicker _picker = ImagePicker();

  /// 默认图片质量（1-100）
  static const int defaultImageQuality = 90;

  /// 从相册选择图片
  /// 
  /// - [imageQuality] 图片质量（1-100），默认 90
  /// - [maxWidth] 最大宽度，null 表示不限制
  /// - [maxHeight] 最大高度，null 表示不限制
  /// 
  /// 返回选择的图片文件，如果用户取消选择返回 null
  /// 
  /// 抛出 [MediaException] 如果选择失败
  static Future<File?> pickFromGallery({
    int imageQuality = defaultImageQuality,
    double? maxWidth,
    double? maxHeight,
  }) async {
    try {
      // 检查相册权限
      final permissionResult = await PermissionService.request(PermissionType.gallery);
      if (permissionResult != PermissionResult.granted) {
        if (permissionResult == PermissionResult.permanentlyDenied) {
          ToastUtils.showError('相册权限被永久拒绝，请在设置中开启相册权限');
          // 自动打开设置页面
          await PermissionService.openSetting();
          throw MediaPermissionException('相册权限被永久拒绝，已引导用户前往设置');
        } else {
          ToastUtils.showError('需要相册权限才能选择图片');
          throw MediaPermissionException('相册权限被拒绝');
        }
      }

      AppLogger.d('开始从相册选择图片...');
      final XFile? file = await _picker.pickImage(
        source: ImageSource.gallery,
        imageQuality: imageQuality,
        maxWidth: maxWidth,
        maxHeight: maxHeight,
      );

      if (file == null) {
        AppLogger.d('用户取消了相册选择');
        return null;
      }

      final imageFile = File(file.path);
      if (!await imageFile.exists()) {
        throw MediaFileException('选择的图片文件不存在: ${file.path}');
      }

      AppLogger.d('相册选择成功: ${file.path}');
      return imageFile;
    } on MediaException {
      rethrow;
    } catch (e) {
      AppLogger.e('相册选择失败', e);
      if (e.toString().contains('permission') || e.toString().contains('权限')) {
        throw MediaPermissionException(
          '相册访问权限被拒绝，请在设置中开启相册权限',
          originalError: e,
        );
      }
      throw MediaException(
        '相册选择失败: ${e.toString()}',
        originalError: e,
      );
    }
  }

  /// 使用系统相机拍照（轻量级）
  /// 
  /// - [imageQuality] 图片质量（1-100），默认 90
  /// - [maxWidth] 最大宽度，null 表示不限制
  /// - [maxHeight] 最大高度，null 表示不限制
  /// 
  /// 返回拍摄的照片文件，如果用户取消拍照返回 null
  /// 
  /// 抛出 [MediaException] 如果拍照失败
  static Future<File?> pickFromCamera({
    int imageQuality = defaultImageQuality,
    double? maxWidth,
    double? maxHeight,
  }) async {
    try {
      // 检查相机权限
      final permissionResult = await PermissionService.request(PermissionType.camera);
      if (permissionResult != PermissionResult.granted) {
        if (permissionResult == PermissionResult.permanentlyDenied) {
          ToastUtils.showError('相机权限被永久拒绝，请在设置中开启相机权限');
          // 自动打开设置页面
          await PermissionService.openSetting();
          throw MediaPermissionException('相机权限被永久拒绝，已引导用户前往设置');
        } else {
          ToastUtils.showError('需要相机权限才能拍照');
          throw MediaPermissionException('相机权限被拒绝');
        }
      }

      AppLogger.d('开始使用系统相机拍照...');
      final XFile? file = await _picker.pickImage(
        source: ImageSource.camera,
        imageQuality: imageQuality,
        maxWidth: maxWidth,
        maxHeight: maxHeight,
      );

      if (file == null) {
        AppLogger.d('用户取消了拍照');
        return null;
      }

      final photoFile = File(file.path);
      if (!await photoFile.exists()) {
        throw MediaFileException('拍摄的照片文件不存在: ${file.path}');
      }

      AppLogger.d('拍照成功: ${file.path}');
      return photoFile;
    } on MediaException {
      rethrow;
    } catch (e) {
      AppLogger.e('相机拍照失败', e);
      if (e.toString().contains('permission') || e.toString().contains('权限')) {
        throw MediaPermissionException(
          '相机权限被拒绝，请在设置中开启相机权限',
          originalError: e,
        );
      }
      throw MediaException(
        '相机拍照失败: ${e.toString()}',
        originalError: e,
      );
    }
  }

  /// 从相册选择视频
  /// 
  /// 返回选择的视频文件，如果用户取消选择返回 null
  /// 
  /// 抛出 [MediaException] 如果选择失败
  static Future<File?> pickVideoFromGallery() async {
    try {
      // 检查相册权限
      final permissionResult = await PermissionService.request(PermissionType.gallery);
      if (permissionResult != PermissionResult.granted) {
        if (permissionResult == PermissionResult.permanentlyDenied) {
          ToastUtils.showError('相册权限被永久拒绝，请在设置中开启相册权限');
          // 自动打开设置页面
          await PermissionService.openSetting();
          throw MediaPermissionException('相册权限被永久拒绝，已引导用户前往设置');
        } else {
          ToastUtils.showError('需要相册权限才能选择视频');
          throw MediaPermissionException('相册权限被拒绝');
        }
      }

      AppLogger.d('开始从相册选择视频...');
      final XFile? file = await _picker.pickVideo(
        source: ImageSource.gallery,
      );

      if (file == null) {
        AppLogger.d('用户取消了视频选择');
        return null;
      }

      final videoFile = File(file.path);
      if (!await videoFile.exists()) {
        throw MediaFileException('选择的视频文件不存在: ${file.path}');
      }

      AppLogger.d('视频选择成功: ${file.path}');
      return videoFile;
    } on MediaException {
      rethrow;
    } catch (e) {
      AppLogger.e('视频选择失败', e);
      if (e.toString().contains('permission') || e.toString().contains('权限')) {
        throw MediaPermissionException(
          '相册访问权限被拒绝，请在设置中开启相册权限',
          originalError: e,
        );
      }
      throw MediaException(
        '视频选择失败: ${e.toString()}',
        originalError: e,
      );
    }
  }
}