import 'dart:io';

import 'package:get/get.dart';
import 'package:path_provider/path_provider.dart';
import 'package:path/path.dart' as p;

class PhotoGroup {
  final String title;
  final int imageCount;
  final RxBool isSelected;
  final List<String> images;
  final RxList<bool> selectedImages;

  int get selectedCount => selectedImages.where((selected) => selected).length;

  PhotoGroup({
    required this.title,
    required this.imageCount,
    required bool isSelected,
    required this.images,
  })  : isSelected = isSelected.obs,
        selectedImages = List.generate(imageCount, (_) => isSelected).obs;

  void toggleSelectAll(bool value) {
    isSelected.value = value;
    selectedImages.assignAll(List.generate(images.length, (_) => value));
  }
}

class SimilarPhotoController extends GetxController {
  final RxList<PhotoGroup> photoGroups = <PhotoGroup>[].obs;

  static final Map<String, List<bool>> _savedSelections = {};
  static bool _hasInitializedSelections = false;

  int get selectedFileCount =>
      photoGroups.fold(0, (sum, group) => sum + group.selectedCount);

  double get selectedFilesSize {
    double totalSize = 0;
    for (var group in photoGroups) {
      for (int i = 0; i < group.images.length; i++) {
        if (group.selectedImages[i]) {
          totalSize += File(group.images[i]).lengthSync();
        }
      }
    }
    return totalSize / 1024; // Convert to KB
  }

  void toggleImageSelection(String groupTitle, int imageIndex) {
    final group = photoGroups.firstWhere((g) => g.title == groupTitle);
    group.selectedImages[imageIndex] = !group.selectedImages[imageIndex];
    group.isSelected.value = group.selectedImages.every((selected) => selected);
    _saveSelections();
  }

  void toggleGroupSelection(String groupTitle) {
    final group = photoGroups.firstWhere((g) => g.title == groupTitle);
    final newValue = !group.isSelected.value;
    group.toggleSelectAll(newValue);
    _saveSelections();
  }

  void _saveSelections() {
    for (var group in photoGroups) {
      _savedSelections[group.title] = group.selectedImages.toList();
    }
    _hasInitializedSelections = true;
  }

  void _restoreSelections() {
    for (var group in photoGroups) {
      // 这里假设每次页面加载时，已选择的状态会保存在 `RxList<bool>` 中。
      group.isSelected.value =
          group.selectedImages.every((selected) => selected);
    }
  }

  @override
  void onInit() {
    super.onInit();
    loadPhotosFromDirectory().then((_) {
      if (_hasInitializedSelections) {
        _restoreSelections();
      }
    });
  }

  Future<void> loadPhotosFromDirectory() async {
    try {
      final Directory appDir = await getApplicationDocumentsDirectory();
      final String photosPath = '${appDir.path}/photos';

      final Directory photosDir = Directory(photosPath);
      if (!await photosDir.exists()) {
        return;
      }

      final List<Directory> subDirs = await photosDir
          .list()
          .where((entity) => entity is Directory)
          .map((e) => e as Directory)
          .toList();

      for (final dir in subDirs) {
        final List<FileSystemEntity> files = await dir
            .list()
            .where((entity) =>
                entity is File &&
                ['.jpg', '.jpeg', '.png']
                    .contains(p.extension(entity.path).toLowerCase()))
            .toList();

        if (files.isNotEmpty) {
          photoGroups.add(PhotoGroup(
            title: 'photo: ${files.length}',
            imageCount: files.length,
            isSelected: false,
            images: files.map((file) => file.path).toList(),
          ));
        }
      }
    } catch (e) {
      print('Error loading photos: $e');
    }
  }
}