import 'dart:io';

import 'package:dio/dio.dart';
import 'package:get/get.dart' hide MultipartFile, FormData;
import 'package:problem_check_system/data/models/image_status.dart';
import 'package:problem_check_system/data/models/sync_status.dart';
import 'package:problem_check_system/data/models/image_metadata_model.dart';
import 'package:problem_check_system/data/models/problem_model.dart';
import 'package:problem_check_system/data/providers/connectivity_provider.dart';
import 'package:problem_check_system/data/providers/http_provider.dart';
import 'package:problem_check_system/data/providers/sqlite_provider.dart';
import 'package:problem_check_system/data/repositories/file_repository.dart';

/// 问题仓库，负责处理问题数据的本地持久化。
/// 它封装了底层数据库操作，为业务逻辑层提供一个简洁的接口。
class ProblemRepository extends GetxService {
  final SQLiteProvider sqliteProvider;
  final HttpProvider httpProvider;
  final ConnectivityProvider connectivityProvider;
  final FileRepository fileRepository = Get.find<FileRepository>();

  RxBool get isOnline => connectivityProvider.isOnline;

  ProblemRepository({
    required this.sqliteProvider,
    required this.httpProvider,
    required this.connectivityProvider,
  });

  /// 更新本地数据库中的一个问题。
  /// 如果问题存在则更新，如果不存在则插入。
  Future<void> updateProblem(Problem problem) async {
    // 检查问题是否存在，通常通过ID判断
    final existingProblem = await sqliteProvider.getProblemById(problem.id!);

    if (existingProblem != null) {
      // 问题已存在，执行更新操作
      await sqliteProvider.updateProblem(problem);
    } else {
      // 问题不存在，执行插入操作
      await sqliteProvider.insertProblem(problem);
    }
  }

  /// 通用查询方法，根据可选的筛选条件获取问题列表。
  /// - `startDate`/`endDate`：筛选创建时间范围。
  /// - `syncStatus`：筛选上传状态（'已上传', '未上传', '全部'）。
  /// - `bindStatus`：筛选绑定状态（'已绑定', '未绑定', '全部'）。
  Future getProblems({
    DateTime? startDate,
    DateTime? endDate,
    String? syncStatus,
    String? bindStatus,
  }) async {
    return await sqliteProvider.getProblems(
      startDate: startDate,
      endDate: endDate,
      syncStatus: syncStatus,
      bindStatus: bindStatus,
    );
  }

  Future<void> insertProblem(Problem problem) async {
    await sqliteProvider.insertProblem(problem);
  }

  Future<void> deleteProblem(String id) async {
    await sqliteProvider.deleteProblem(id);
  }

  // * /api/Objects/association/${file.name}
  /// 上传单个问题及其所有关联的图片。
  Future<Problem> uploadProblem(
    Problem problem, {
    required CancelToken cancelToken,
    required void Function(double progress) onProgress,
  }) async {
    try {
      final newImages = problem.imageUrls
          .where((img) => img.status == ImageStatus.local)
          .toList();
      final totalFilesToUpload = newImages.length;
      int filesUploadedCount = 0;

      // 1. 上传所有状态为 ImageStatus.local 的新图片
      final List<String> remoteUrls = [];
      for (var image in newImages) {
        // 修正：当上传被取消时，抛出异常而不是无返回值的 return
        if (cancelToken.isCancelled) {
          throw DioException(
            requestOptions: RequestOptions(path: ''),
            type: DioExceptionType.cancel,
            error: '上传已取消',
          );
        }
        final imageFile = File(image.localPath);
        final url = await fileRepository.uploadImage(
          imageFile,
          cancelToken: cancelToken,
          onSendProgress: (sent, total) {
            double overallProgress =
                (filesUploadedCount + (sent / total)) / totalFilesToUpload;
            onProgress(overallProgress);
          },
        );
        remoteUrls.add(url);
        filesUploadedCount++;
      }
      onProgress(1.0); // 确保图片上传进度为100%

      // 2. 构建 API payload
      final List<String> finalRemoteUrls = [];
      int newImageIndex = 0;
      for (var image in problem.imageUrls) {
        if (image.status == ImageStatus.synced) {
          finalRemoteUrls.add(image.remoteUrl!);
        } else if (image.status == ImageStatus.local) {
          finalRemoteUrls.add(remoteUrls[newImageIndex]);
          newImageIndex++;
        }
      }

      final apiPayload = {
        'id': problem.id,
        'description': problem.description,
        'location': problem.location,
        'imageUrls': finalRemoteUrls, // 使用整合后的网络URL列表
        'createdAt': problem.creationTime.toIso8601String(),
        // ... 其他字段
      };

      // 3. 发送给服务器
      final response = await httpProvider.post(
        '/api/problem',
        data: apiPayload,
        cancelToken: cancelToken,
      );

      // 4. 处理服务器响应，并更新本地模型状态
      if (response.statusCode == 200) {
        final List<ImageMetadata> updatedImageMetadata = [];
        int uploadedUrlIndex = 0;
        for (var image in problem.imageUrls) {
          if (image.status == ImageStatus.local) {
            updatedImageMetadata.add(
              ImageMetadata(
                localPath: image.localPath,
                remoteUrl: remoteUrls[uploadedUrlIndex],
                status: ImageStatus.synced,
              ),
            );
            uploadedUrlIndex++;
          } else {
            updatedImageMetadata.add(image);
          }
        }

        // 返回一个包含新同步状态和更新后图片列表的对象
        return problem.copyWith(
          syncStatus: SyncStatus.synced,
          imageUrls: updatedImageMetadata,
        );
      } else {
        throw Exception('问题上传失败，状态码: ${response.statusCode}');
      }
    } on DioException {
      rethrow;
    }
  }

  /// 新增：上传问题列表。
  /// 遍历问题列表，并计算总进度。
  Future<List<Problem>> uploadProblems(
    List<Problem> problems, {
    required CancelToken cancelToken,
    required void Function(double progress) onProgress,
  }) async {
    final int totalProblems = problems.length;
    final List<Problem> updatedProblems = [];

    try {
      for (int i = 0; i < totalProblems; i++) {
        // 如果取消令牌被触发，停止并返回
        if (cancelToken.isCancelled) {
          break;
        }

        final problemToUpload = problems[i];

        // 传递一个子进度回调，用于计算单个问题的进度
        final updatedProblem = await uploadProblem(
          problemToUpload,
          cancelToken: cancelToken,
          onProgress: (progress) {
            // 计算总体进度：(已完成的问题数 + 当前问题的进度) / 总问题数
            final overallProgress = (i + progress) / totalProblems;
            onProgress(overallProgress);
          },
        );
        updatedProblems.add(updatedProblem);
      }
      return updatedProblems;
    } on DioException {
      rethrow;
    }
  }

  getProblemsForSync() {
    return sqliteProvider.getProblemsForSync();
  }
}