import 'dart:convert';
import 'dart:io';

import 'package:path_provider/path_provider.dart';

/// Used to ease up accessing local files
class StorageAccess {
  /// Get files in `recent` folder, which contains recently opened pages
  static Future<List<Map<String, dynamic>>> get recent async {
    var files =
        Directory("${(await getApplicationDocumentsDirectory()).path}/recent");
    if (!files.existsSync()) files.createSync();
    return files
        .listSync()
        .whereType<File>()
        .toList()
        .map<Map<String, dynamic>>((e) => jsonDecode(e.readAsStringSync()))
        .toList();
  }

  static void addToRecents(String pageName, String pageKey) async {
    var files =
        Directory("${(await getApplicationDocumentsDirectory()).path}/recent");
    if (!files.existsSync()) files.createSync();
    var content = files.listSync();
    if (content.length > 4) {
      // delete last recent
      // TODO: configurable
      File? f;
      for (var file in content) {
        if (file is Directory) continue;
        var modi = (await file.stat()).modified;
        if (f == null || (await f.stat()).modified.isAfter(modi)) {
          f = file as File;
        }
      }
      f!.deleteSync();
    }

    var recent = File("${files.path}/${pageName.replaceAll(' ', '_')}");
    if (recent.existsSync()) {
      // if recent already exists, simply change date
      var recentContent = jsonDecode(recent.readAsStringSync());
      recentContent["date"] = DateTime.now().millisecondsSinceEpoch;
      recent.writeAsStringSync(jsonEncode(recentContent));
    } else {
      // else create files
      var recentContent = {
        "date": DateTime.now().millisecondsSinceEpoch,
        "name": pageName,
        "key": pageKey
      };
      recent.writeAsStringSync(jsonEncode(recentContent));
    }
  }
}